Suppressing Synonymy with a Homonym: The Emergence of the Nomenclatural Type Concept in Nineteenth Century Natural History
Journal of the History of Biology
Suppressing Synonymy with a Homonym: The Emergence of the Nomenclatural Type Concept in Nineteenth Century Natural History
0 Department of Psychology Utrecht University Utrecht The Netherlands
1 Department of Philosophy and Religious Studies Utrecht University Utrecht The Netherlands
2 JOERI WITTEVEEN Descartes Centre for the History and Philosophy of the Sciences and the Humanities Utrecht University Utrecht The Netherlands
'Type' in biology is a polysemous term. In a landmark article, Paul Farber (Journal of the History of Biology 9(1): 93-119, 1976) argued that this deceptively plain term had acquired three different meanings in early nineteenth century natural history alone. 'Type' was used in relation to three distinct type concepts, each of them associated with a different set of practices. Important as Farber's analysis has been for the historiography of natural history, his account conceals an important dimension of early nineteenth century 'type talk.' Farber's taxonomy of type concepts passes over the fact that certain uses of 'type' began to take on a new meaning in this period. At the closing of the eighteenth century, terms like 'type specimen,' 'type species,' and 'type genus' were universally recognized as referring to typical, model members of their encompassing taxa. But in the course of the nineteenth century, the same terms were co-opted for a different purpose. As part of an effort to drive out nomenclatural synonymy - the confusing state of a taxon being known to different people by different names - these terms started to signify the fixed and potentially atypical name-bearing elements of taxa. A new type concept was born: the nomenclatural type. In this article, I retrace this perplexing nineteenth century shift in meaning of 'type.' I uncover the nomenclatural disorder that the new nomenclatural type concept dissolved, and expose the conceptual confusion it left in its tracks. What emerges is an account of how synonymy was suppressed through the coinage of a homonym.
Nineteenth century natural history was rife with talk of ‘types’ in
various guises. In a landmark article from 1976, historian of biology Paul
Farber set out to disentangle the web of connotations of this deceptively
plain term. He pointed out that ‘type’ in this period ‘‘was not a simple
notion. Rather, it was a constellation of concepts that zoologists
employed in different specialties, assigned to different levels of
organization, and interpreted in different ways’’ (Farber, 1976, p. 93). Farber
argued that the distinct usages of ‘type’ pointed towards three different
‘type concepts’: the morphological type concept, the classification type
concept, and the collection type concept.
Farber’s analysis imbued some much-needed historical data into the
diatribe against ‘typological thinking’ that had been launched by Ernst
Mayr and his fellow Modern Synthesis architects.1 Farber rightly
emphasized that speaking of ‘typological thinking’ as a monolithic and
backward category ‘‘does violence to the historical record and confuses
contemporary debates rather than clarifies them’’ (Farber, 1978, p. 91).
He showed that pre-Darwinian type-talk was not hung up on Platonic
idealism or Aristotelian essentialism, but rather involved a spectrum of
flourishing empirical and theoretical endeavors.
Farber’s 1976 paper has deservedly attained the status of a classic in
the history and philosophy of biology. His account of types has formed
the backbone of many studies of late eighteenth and nineteenth century
taxonomy and morphology, and continues to be viewed as a conceptual
1 E.g. Dobzhansky (1967), Mayr (1959, 1976), and Simpson (1961). It is generally
thought that typology/population dichotomy was a purely rhetorical ploy, which Mayr
conjured up from thin air in the early 1950s (e.g. Chung, 2003; Winsor, 2006).
Elsewhere, I show that the actual origination history of the typology/population dichotomy
is considerably more complicated than this (Witteveen, under review[a]). It originated
with independent (and disciplined) arguments by Dobzhansky and Simpson against
distinct notions of type, used in different methodological, conceptual, and theoretical
contexts. Mayr later swept up these individually meaningful type/population contrasts
and recombined them into a rather obscure argument against typological thinking.
springboard for improving our grip on nineteenth century natural
It is nonetheless high time to revisit Farber’s account of types, for
some things that he writes are prima facie puzzling. Take, for example,
the claim that his tripartite taxonomy of type concepts should not be
taken ‘‘[to] correspond to nineteenth-nineteenth-century definitions of
the word ‘type,’’’ since the word was generally ‘‘used in a very loose
manner’’ (Farber, 1976, p. 93). What, then, did Farber attempt to
capture with his taxonomy of type concepts? Obviously, he was not
anachronistically imposing his own categorization of type concepts on
history. Instead, Farber intended to articulate distinct interpretations
that were implicit in widespread nineteenth uses of the word, as part of
distinct constellations of theory, practice and belief.
This is illustrated by an observation Farber makes about the
confused practices of some naturalists, when viewed against the
background of type concepts that were recognized by their
contemporaries. He notes that in the context of handling so-called ‘type
specimens,’ some naturalists were ‘‘confusing the collection
typeconcept with the morphological or classification type-concept’’
(Farber, 1976, p. 107).
However, this same observation also suggests that there is
something amiss with Farber’s own classification of type concepts. For,
when Farber specifies how certain naturalists confused the collection
type concept with other type concepts, he gives an account of the
collection type concept that is at odds with his analysis from earlier in
his paper. In consequence, it appears that Farber is of two minds
about what the collection type concept really amounted to, and which
practices it warranted.
I will show that this internal tension in Farber’s account originates in
an assumption that turns out to be problematic. Farber’s account is built
on the hidden assumption that early nineteenth century uses of ‘type’ had
stabilized around an array of meanings that correspond to his three type
concepts. What Farber hereby overlooks, is that certain uses of ‘type’
underwent a radical change in meaning in this period. At the closing of the
eighteenth century, terms such as ‘type specimen,’ ‘type species,’ and ‘type
genus’ had referred to typical members of their respective taxa. They were
taxon elements that could serve as models for their respective taxa in the
practice of classification. Yet by the end of the nineteenth century, these
same terms had lost their connotation to anything ‘typical’; they now
referred to the fixed (and potentially aberrant), name-bearing elements of
those taxa. The nomenclatural type concept had emerged.
To recognize the nomenclatural type concept for what it is, is to
realize that there is a story to be told about how it originated.3 This
intriguing history forms the heart of this paper. I will show that the
emergence of the nomenclatural type concept was at once virtually
inevitable and entirely incidental. It was virtually inevitable, because the
only way taxonomy could continue to be pursued in the radically
changing context of the nineteenth century was by tying names to fixed
name-bearing elements. Only this method held the promise of calling to
a halt the rapid increase in synonymy – the pervasively confusing state
of one taxon being known to different people by different names. On the
other hand, it was entirely incidental that these name-bearing elements
would become known as ‘types.’ Moreover, this choice of terminology
invited confusion: references to ‘the type of a taxon’ became ambiguous
between a taxon’s typical element and its name-bearing element. In an
effort to drive out synonymy, ‘type’ was being turned into a confusing
Farber’s Taxonomy of Type Concepts
Before addressing the problem with Farber’s taxonomy of type
concepts, I will give a brief overview of the type concepts he distinguishes.
The most familiar type concept he discusses is the morphological type. It
was defined as an abstract plan, schema, or blueprint of a (taxonomic)
group of organisms that picks out its defining characters: ‘‘The
morphological type … was a plan of organization that in principle consisted
of essential elements’’ (Farber, 1976, p. 107). Farber attributes the first
exposition of this type concept in modern history to the comparative
anatomist Louis-Jean-Marie Daubenton (1716–1800) ‘‘whose
morphological descriptions of quadrupeds marked the beginning of the modern
3 As far as I am aware, Lorraine Daston is the only one who has gestured to
important parts of this history (Daston, 2004; Daston and Galison, 2007, p. 109ff.),
albeit without clearly articulating the shift in type concepts. Instead, she reads the
history of the type specimen notion through the lens of a larger
historical–epistemological framework (Daston and Galison, 2007). I do not have the space here to discuss
Daston’s argument in any detail, but argue elsewhere that her approach is problematic
(Witteveen, under review[b]). The constraints of her historiographical framework cause
her to overlook several key nineteenth century developments, and leads her to
misconstrue the notion of a type specimen that was being hammered out.
science of comparative anatomy’’ (Farber, 1976, p. 100).4 As the
longtime collaborator of Georges-Louis Leclerc de Buffon (1707–1788),
Daubenton provided anatomical descriptions of morphological types
for his Histoire Naturelle (Buffon, 1749), by listing sets of exclusive and
essential morphological characters as plans on which individual species
had been constructed.
Through Buffon’s works, the morphological type concept started to
spread, and soon became applied to other levels of the taxonomic
hierarchy. Johann Wolfgang von Goethe (1749–1832) applied the
morphological type concept to the entire kingdom of plants through his notion of
the Urpflanze (Lenoir, 1978; Nisbet, 1967).5 Another example of the
deployment of the morphological type concept at a higher taxonomic level
was Georges Cuvier’s (1769–1832) division of life into four
embranchements, based on four fundamentally different kinds of nervous systems.
Farber notes that, over time, different interpretations of the
morphological type were developed. Cuvier followed Daubenton in working with
a functional conception of morphological types, while others, such as
E´tienne Geoffroy Saint-Hilaire (1772–1844), argued that meaningful
plans had to be based on structural correspondences. Hence, the famous
debate between Cuvier and Geoffroy can be understood as a controversy
over the nature of morphological types – that morphological types existed
was not at issue (Appel, 1987). A similar debate over the nature of types
and the empirical basis on which they should be discerned arose in the
nineteenth century, when the importance of embryological evidence in the
description of morphological types became a topic of heated debate
(Lyons, 1999; Trienes, 1989). As Lenoir (1978) has pointed out, the
metaphysical status of morphological types also allowed for flexibility of
interpretation: whereas Kant and Goethe considered morphological
plans to be ‘regulative types’ the later Naturphilosophen gave them a realist
interpretation, turning them into the ‘constitutive types’ that dominated
much of nineteenth century morphology and embryology.6
The second type concept Farber distinguishes is the classification
type. A classification type is an exemplary member of a taxonomic
group that can be used to determine the group’s boundaries by
comparing and contrasting it with other potential members of that group.
4 Others have traced the morphological type concept all the way back to antiquity
(Hammen, 1981; Toepfer, 2011).
5 Though, as Riegner (2013) has recently emphasized, Goethe emphasized the dy
namic, developmental aspects of morphological types.
6 For more on the diverse historical interpretations of morphological types, see Levit
and Meister (2006), Nyhart (1995), Richards (2002), and Rupke (2009), among many
Farber argues that this was the meaning of such notions as ‘type species’
and ‘type genus’ in the late eighteenth and early nineteenth century.
Cuvier, for example, used classification types at the genus-level when he
wrote: ‘‘Not being able to assign to each family an equivalent and
exclusive character, we will limit ourselves at this time to indicating
families by names derived from the most well-known genus of each
family; the genus which one can consider as the type and from which it
is easiest to form an idea of the family’’ (Cuvier and Valenciennes, 1828,
vol. I, p. 571; cited in Farber, 1976, p. 103). Buffon similarly made use
of classification types at the species-level when he used the European
flycatcher as a model of comparison in assigning twenty-four other
species to the same genus (Buffon, 1778, IV, pp. 517–518).
Farber notes that in the early nineteenth century ‘‘the use of the
classification type-concept increased dramatically and became explicit rather
than implicit’’ (Farber, 1976, pp. 94–95). That is, taxonomists
increasingly started using phrases like ‘type (of the) species’ and ‘type (of the)
genus’ to refer to model members of taxonomic groups. This terminology
was popularized by William Whewell (1794–1866), who named the
practice of assigning and using classification types the ‘Method of Type’:
Natural Groups are best described, not by any definition which
marks their boundaries, but by a Type which marks their centre.
The Type of any natural group is an example which possesses in a
marked degree all the leading characters of the class … The
typespecies of every genus, the type-genus of every family, is, then, one
which possesses all the characters and properties of the genus in a
marked and prominent manner.
Whewell (1840, pp. xxxii, 477)
Classification types were often used as an inductive means of narrowing
in on the description of a morphological type.7 Peter Stevens has argued
that this use of classification types was especially prominent in botany,
as plants were often found to be insufficiently ‘‘morphologically
coherent’’ to allow for direct application of the morphological type
concept (Stevens, 1984, p. 169).
As with the morphological type concept, the classification type concept
was interpreted differently by different taxonomists. Some argued that there
were definite, typical, representative members of each class in nature. This
attitude was central to the quinary theory of classification of William John
Swainson (1789–1855). Together with other quinary theorists such as
William Sharp Macleay (1792–1865) and Nicholas Aylward Vigors (1785–
1840), Swainson believed that animal taxa needed to be arranged in nested
‘circles of five.’ He argued that each circle had a representative typical group
embodying the highest degree of organization, from which the other four
groups of the same rank departed in various ways. Swainson’s classification
type concept thus was ‘‘a complex notion predicated on the principles of his
system of classification’’ (Farber, 1976, p. 115).8 Whewell, on the other
hand, conceived of classification types as being independent of any
particular taxonomic theory. He emphasized the role of classification types as
heuristic devices, stressing that ‘‘we cannot say of any one genus that it must
be the type of the family, or of any species that it must be the type of the
genus’’ (Whewell, 1840, p. 477).
Finally – and this will become important in a moment – Farber notes
that ‘‘the classification type-concept also doubled as a name carrier in
nomenclature. The model species was used to determine the genus
name, so that if at a later date the genus were split or rearranged, the
group that contained the type species was given the original name’’
(Farber, 1976, p. 95).
The third and final type concept Farber distinguishes, the collection
type concept, covers the concrete ‘type specimens’ stored in the collections
of dried plants known as ‘herbaria.’ Farber notes that, functionally
speaking, the collection type concept was ‘‘[s]imilar to the classification
type-concept … the collection type concept served as a model and name
carrier’’ (ibid., p. 97). He nevertheless considers type specimens to form a
separate class of types, because of their tangible nature. Unlike type
species or type genera, type specimens could be picked up, preserved,
stored, labeled, displayed and exchanged. The collection type concept was
therefore wound up with taxidermic techniques, networks of exchange,
and natural history collections (Farber, 1977, 1980).
Farber’s overall taxonomy of type concepts is summarized in Table 1. On
first inspection, it appears elegant and parsimonious. It seems to capture
some high-level distinctions in early nineteenth century uses of the word
‘type,’ which historians are well-advised to keep apart. However, when we
give Farber’s taxonomy a closer look, an internal tension appears that
8 For a different, late nineteenth century use of classification types in a quinarian
context, see Coggon (2002).
morphological type classification type
raises questions about the overall coherence of his account. This tension
surfaces when, based on the distinctions he has drawn, Farber criticizes how
some nineteenth century naturalists deployed the collection type concept.
Potentially, the main problem of interpretation with the collection
type-concept had to do with considering the type-specimen truely
[sic] typical of the species. There was little to recommend such a
practice. The first description of a species was often made from an
incomplete knowledge of the full range of variation within the
species. If one argued that a type-specimen should be replaced by a
more typical specimen when additional knowledge of the species
was obtained, the entire value of the concept of the collection
typeconcept [sic] as a name carrier and reference for the original
description would be lost …. [N]aturalists who wished to treat
typespecimens as typical specimens, were confusing the collection
typeconcept with the morphological or classification type-concept.
Farber (1976, pp. 105–106)
There is something odd about the criticism Farber voices here. In the
previous section we saw that Farber characterized type specimens (i.e.
collection types) as well as type species and type genera (i.e. classification
types) as having served essentially the same roles at different hierarchical
levels (see Table 1). He argued that all these ‘type elements’ served both as
classificatory models and as name-carriers for their encompassing taxa.
Yet, in the quotation above Farber backpedals on defining type specimens
as classificatory models, by stating that their ‘‘entire value’’ lay in the role
of being fixed bearers of taxon names. Treating a collection type as a
model that could be replaced with a more typical exemplar is now
portrayed as having been illegitimate and illogical.
Farber thus leaves us with two conflicting accounts of what the
distinction between collection and classification types consisted in. At first he
portrays the collection type concept as a functionally similar but
pragmatically separable kind of classification type concept – collection types as
tangible classification types, – but later he suggests that collection types
and classification types were functionally at odds. Which of these
accounts is the correct one?
Neither is. Instead, the tension in Farber’s account signals a problem
with his overall approach towards uncovering nineteenth century type
concepts. Farber assumes that the terms ‘type specimen,’ ‘type species,’
and ‘type genus’ had stable (if implicit) meanings across the period
ranging from the late-eighteenth to the mid-nineteenth century. In
reality, however, these terms started to take on a new meaning in the
early nineteenth century. At the end of the eighteenth century, everyone
understood ‘type of a taxon’ to refer to a typical element that could serve
as a model member for exploring the limits of its encompassing taxon. By
the end of the nineteenth century, ‘type of a taxon’ had come to refer to
the fixed (and potentially atypical) name-bearer of a taxon name.
To account for the nineteenth century change in meaning of a ‘type
element,’ we need to modify Farber’s taxonomy by setting it in motion.
We need to recognize that extant type terms became associated with an
entirely novel type concept. A term like ‘type species’ evolved from
signifying a classification type towards betokening a nomenclatural type. The
same goes for terms like ‘type specimen’ and ‘type genus.’ Table 2 shows
how Farber’s taxonomy needs to be modified in this light. A new category
of nomenclatural types is recognized at the same level as that of
classification types. Each of these two categories covers the meaning of ‘type
specimen,’ ‘type species,’ and ‘type genus’ for a different period.
Using this revised taxonomy, we can start to make sense of Farber’s
allegation that certain nineteenth taxonomists were confusing type
concepts. The point Farber was getting at, is that when taxonomists
started using the term ‘type specimen’ to refer to a fixed name-bearing
specimen (i.e. a nomenclatural type specimen), this implied that such a
Type concept Morphological type Classification type
Definition An abstract A taxon or taxon-element A taxon or taxon-element
representation that serves as classificatory that serves as name-bearer
of the essential model for of its encompassing for the name of its
features of a taxon taxon. A ’typical’ representative. encompassing taxon.
Example/ The vertebrate Type specimen; type species; Type specimen; type
instantiation archetype type genus species; type genus
specimen should not be replaced with a more typical exemplar at a later
time. Doing so amounted to treating nomenclatural types as if they were
classification types. This confusion between type concepts also manifested
itself in the use of a nomenclatural type specimen as a model for the
classification of other specimens. Sometimes this would have worked – a
nomenclatural type specimen could be genuinely exemplary – but there
was no principled reason to always expect this to be the case. Since
nomenclatural type specimens were often designated upon the discovery
of a small sample of material from a (putatively) new species, it was quite
likely that they would be rather aberrant members of their species in the
light of later discoveries.
Apart from allowing us to improve Farber’s account, the revised
taxonomy of type concepts points to an important new explanatory
project. It raises the question how and why terms like ‘type specimen’
and ‘type species’ shifted meaning in the course of the nineteenth
century. How could these terms become detached from connotations of
typicality, and gain the new meaning of ‘fixed name-bearer’? What
developments drove this change? To answer these questions we need to
delve into late-eighteenth century theory and practice of naming and
classifying, and follow their development as we reach the maelstrom of
early nineteenth century taxonomy.
From Method of Type to Type Method
Linnaeus and the Method of Type
Linnaeus (1707–1778) never wrote about types. Still, he clearly falls in
the category of those who used the classification type concept
‘implicitly,’ as Farber rightly notes.9 Starting from a set of carefully selected
‘chief species’ (prima species) Linnaeus made one-by-one comparisons
with other known species in order to gradually determine the
boundaries between genera. If the characters of a newfound species matched
those of the chief species sufficiently well, the new species was added to
the genus, and all characters by which the two species differed were
cancelled from the description of the genus.10 By iterating this
proce9 ‘‘One can find similar implicit classification type-concepts in the writings of other
major eighteenth-century writers, such as Carl von Linn e´’’ (Farber, 1976, p. 94).
10 Many commentators have noted that, in practice, Linnaeus frequently failed to
remove the dissenting characters from his description, because of a lack of time (Mu¨
llerWille, 2007; Winsor, 2003). This has enabled later authors to retrace which species he
used a prima specie (Pennell, 1930).
dure, Linnaeus could provide increasingly accurate descriptions of the
‘natural character’ of a genus (Linnaeus, 1751, §193; Mu¨ ller-Wille, 2006,
2007; Stearn, 1957, p. 37).
Linnaeus referred to this practice as the ‘method of collation’ (collatio
specierum). In the Flora Lapponica, for example, he remarked that it could
not be said with certainty that the genus Andromeda was distinct from the
genus Erica until he would have ‘‘collated flowers of more species from
both genera’’ (Linnaeus, 1737b, p. 126). Many later commentators have
recognized this practice as an application of Whewell’s Method of Type.11
The botanist Henry Knute Svenson (1897–1986) stated that from a
Linnaean viewpoint ‘‘we may think of genera as broadening concentric circles
such as the rings formed by pebbles thrown into water: the initial impact
representing the type species of the genus, and the resulting concentric
rings the accretion of species through historical usage’’ (Svenson, 1945, p.
291). The American botanist Francis Whittier Pennell (1886–1952)
remarked in a similar vein that in the Genera Plantarum ‘‘each [generic
description] was prepared from a species carefully selected as typical’’
(Pennell, 1933, p. 38).12
Linnaeus emphasized that only the most seasoned taxonomists could
be trusted in their selection of classification types (Linnaeus, 1751, p.
193). Only the expert possessed the requisite tacit knowledge for
selecting a truly typical species for each genus. Another Linnaean
recommendation for the selection of classification type species was that
they be species with putative medicinal properties.13 This is illustrated
by the fact that a large number of the species Linnaeus used as
classification types for the fifth edition of Genera Plantarum (Linnaeus, 1754)
are species that he had included in his recently published Species
Plantarum (Linnaeus, 1753) with the epithet ‘officinales’ – a term
denoting exemplary medicinal value with regard to some property
11 Whewell mentioned Linnaeus, Adanson and de Candolle (the elder) as examples of
taxonomists who had ‘‘practically applied’’ and ‘‘theoretically enunciated’’ what he
regarded as the ‘‘sound maxims of classificatory science,’’ which obviously included the
Method of Type (Whewell, 1840, p. 463).
12 Also see Pennell (1930, 1939). Many other taxonomists and historians have
similarly noticed Linnaeus’ deployment of the Method of Type (e.g. Hitchcock and Green,
1929; Stearn, 1959, 1960; Winsor, 2003).
13 Officinal species served an important role in the larger economic context in which
Linnaeus’s classificatory endeavors were situated. Ultimately, his generic classifications
served the practical goal of presenting potential substitutes for imported products, so as
to reduce dependence on trade, which he perceived as essentially parasitic on the
domestic economy (Koerner, 1999).
common to the genus (Pennell, 1930; Ho¨ vel, 1999).14 Hence, later
taxonomists rightly observed that ‘‘the type of each genus of Linnaeus as
stated by him is ‘the best known European or officinal species’ it
contains,’’ (Jordan, 1901, p. 501) and that ‘‘among Linnaean genera …
such names as communis, vulgaris, typicus, and officinalis would seem to
point out typical species’’ (Hitchcock, 1925, p. 131).
Meanwhile, Linnaeus was aware that even classifications made by
experts were fallible. He realized that future taxonomists, with more
knowledge about more species at their disposal, would likely judge that
some genera were really composites, and needed to be split. Moreover,
Linnaeus perspicaciously observed that this inherent fickleness of
classifications could have serious consequences for the stability of
taxonomic nomenclature. A name that was once established could all too
easily get lost in a sequence of splitting events. Or worse, different
taxonomists might start using the same original name to refer to
different segments of a divided taxon. Nomenclatural chaos would ensue.
In the Fundamenta Botanica, his first collection of ideas about reform in
botanical taxonomy, Linnaeus offered a solution to these problems by
means of proposing a procedural rule. Aphorism 246 of that work
If an established genus has to be split up into several, according to
the Law of Nature and Art, then the name that formerly belonged
to the whole should be kept to denote the plant that is most vulgar
With this aphorism, Linnaeus suggested that the assignment of
taxonomic names be made dependent on (expert) taxonomic judgment. Any
taxonomist who would be able to ascertain the typical—i.e. vulgar and
officinal—species of a genus would also be able to apply its name
correctly when splitting the genus. In other words, aphorism 246 made the
assignment of genus names dependent on deployment of the Method of
Type. Classification types would double as name-bearers.
Linnaeus reiterated this aphorism in the Critica Botanica, warning
that ‘‘inextricable confusion would arise’’ if taxonomists would be
allowed to ‘‘choose indifferently’’ which part of a genus to apply the
14 An officina was a building, often adjacent to a herbal garden, were medicaments
were prepared from plant extracts (Pearn, 2010).
15 ‘‘Si genus receptum, secundum jus naturae & artis, in plura dirimi debet, tum
nomen antea commune manebit vulgatissimae & officinali plantae.’’
original name to (Linnaeus 1737a, p. 99). Linnaeus’s aphorism reached
later generations of taxonomists through his widely read Philosophia
Botanica (Linnaeus, 1751). His student Johan Christian Fabricius
(1745–1808), for example, included aphorism 246 almost verbatim in his
influential Philosophia Entomologica16 (Fabricius, 1778, §30). In the
early nineteenth century, John Lindley’s (1799–1865) widely read An
Introduction to Botany made mention of the ‘‘Linnaean canon’’ that was
recognized for providing stability to taxonomic nomenclature: ‘‘If an
old genus is divided into several new ones, the old name will remain with
the species that is best known’’ (Lindley, 1832, p. 456). One would
hardly suspect that soon enough, taxonomist would reject this principle
because of its contribution to nomenclatural chaos.
Names, Meaning, and Typicality
To understand why and how aphorism 246 and its later incarnations
came under threat, we will need to make an excursion into some general
developments in early nineteenth century taxonomy. As the Napoleonic
Wars drew to close, overseas surveys and expeditions started to bring
home masses of new specimens from previously unexplored areas,
driving a rapid expansion of botanical and zoological collections in
Britain and on the continent. Naturalists who sifted through the
materials that were brought home soon discovered numerous new
species, genera, and even entire families.17 Joining the sudden increase in
specimens needing to be named and classified was an increase in
taxonomists who wished to be involved in the naming and classifying. A
new branch of self-fashioned British provincial radicals started
practicing taxonomy as a pastime, and colonial collectors began to name
species on their own (McOuat, 1996; Secord, 1994; Endersby, 2008).
The metropolitan establishment harbored more than a few
reservations about the involvement of these new classes of amateur
taxonomists in these endeavors. Imperial botanists objected that colonial
collectors tended to raise mere varieties to the status of species, and that
they did so mainly to derive prestige from introducing new names. To
the imperial experts these new names useless, redundant, and a cause of
16 ‘‘Si genus receptum, secundum leges naturae et artis, in plura dirimatur, tum nomen
antea commune vulgatissimo insecto manebit.’’
17 Whewell mentioned that ‘‘Linnaeus knew approximately 10,000 species of plants; a
few decades later this number had already swelled to 60,000’’ (Whewell, 1840, p. 489).
By the mid-1830s this number had risen sharply, as it was reported that ‘‘new species are
joined to those known to Linnaeus, in the proportion of at least 100 to 1’’ (Westwood,
1836, p. 562).
confusion. Joseph Dalton Hooker (1817–1911), soon to become
assistant director of the Royal Botanical Gardens at Kew, lamented the
‘‘chaos of synonymy which has been accumulated by the thoughtless
aspirants to the questionable honour of being the first to name a
species’’ (Hooker, 1853, xiv).18
From the side of provincial radicals, the contributions to the ‘chaos
of synonymy’ were compounded by another factor. Radical reformists
argued that many taxon names that had once been ‘expressive’ of
typical and distinguishing features of taxa seemed to be rather ‘off’ in the
light of recent discoveries. Hence, a good number of Linnaean and
colloquial names needed to be replaced with more meaningful names.
Even more than the careless splitting of taxa, these arguments about
meaning were anathema to the conservative metropolitan
establishment.19 Apparently, the radicals had deeply misunderstood what purpose
names served. As Linnaeus had already made clear, a good name was
simply a memorable one. The ulterior value of names was entirely
constituted in them being good mnemonic devices. Names should therefore
not be too long, too similar to others, or be mixtures of Latin and Greek
words.20 Ideally, a name would capture the distinguishing features of a
taxon, but neither Linnaeus nor his followers considered it essential for a
name to wear its ‘meaning’ on its sleeve. ‘‘Names have the same value on
the marketplace of botany as coins have in public affairs, which are daily
accepted as certain values by others, without metallurgical examination’’
(Linnaeus, 1737a, §284). Not the most expressive, but the first
(wellformed) name given to a taxon should be counted as the rightful name for
that taxon: ‘‘priority in time confers precedence’’ (Linnaeus, 1737a, §243).
The controversy between radicals and conservatives flamed up
properly over an article written by the anonymous S. D. W., who argued
that the recent discovery of a white specimen of the species ‘coalhood’
was good reason to replace its name: ‘‘With regard to the Scientific
Name of the Coalhood, I have ventured to suggest Denisirostra
atricapilla, as being more definite and expressive than the name of
Lin18 Hooker’s collaborator George Bentham (1800–1884) similarly proclaimed that ‘‘[i]t
is only second rate botanists who pride themselves on the number of names, good or
bad, to which their initials can be attached’’ (Bentham, 1878, p. 190).
19 For a broader and more detailed treatment of the controversies that ensued, see
20 Generally speaking, only the improper form of an extant name (e.g. not being in
Latin, or being barbarian) would be a reason for Linnaeus to introduce a new name: ‘‘If
it is decided that none of the synonyms is really suitable for the plant, then necessity
compels us to make up a new one’’ (Linnaeus, 1737a, p. 258; cited in Dayrat, 2010, p.
naeus, Loxia Pyrrhula’’ (S.D.W., 1834, p. 593). S. D. W.’s article raised
the hackles of Hugh Edwin Strickland (1811–1853), a conservative,
Oxford-educated naturalist. Strickland quickly drafted a reply in which
he strongly objected to the idea of substituting more ‘expressive’ names
for accepted ones, ‘‘a practice which appears to me highly detrimental to
the progress of natural history’’ (Strickland, 1835, p. 36). He continued
by teaching S. D. W. and his allies some Linnaean philosophy of names:
‘‘[I]n order that the object of the specific name may be duly performed,
it is essential that a name be universally adopted, and, therefore, never,
or very rarely, altered. But it is not, I think, essential that the meaning of
the name should precisely designate the species; or, indeed, that it
should have any meaning at all’’ (Strickland, 1835, p. 38). With
Linnaeus, Strickland also held that once a name was assigned to a species, it
should be retained as its unique and memorable marker. Only a little
reflection was needed to realize that S. D. W.’s alternative of ‘updating’
species names in the light of new knowledge would be unworkable:
Can S. D. W., for instance, expect that the whole republic of
science will take the trouble of relabelling their cabinets, altering their
catalogues, or making notes in their works of reference, because an
anonymous writer fancies that he can improve Pyrrhula vulgaris by
changing it to Densirostra atricapilla? Again, if some adopt the
alteration, a large number will not: and hence it is that we rarely
find the same species labelled alike in two different museums. In
short, if this practice be once given way to, there will soon be an
end of all nomenclature, and, through it, of all science.
Strickland (1835, pp. 38–39)
Strickland’s message was clear: ‘‘[T]he evil of changing a name … is much
greater than any advantage supposed to result from substituting a term
which is ‘more appropriate.’’’ Reformists like S. D. W. who pressed for
‘better’ names failed to appreciate that taxon names, like proper names,
are ‘‘arbitrary signs adopted to represent real things or conceptions’’
(Strickland, 1835, p. 37; italics in original). There was, in other words, a
‘‘complete parallel’’ between species names and names of men: ‘‘The first
discoverer of a species may be regarded as its parent or godfather; who
bestows on it any name he thinks fit, and publishes it to the scientific world
in some standard work, as in a parish register’’ (Strickland, 1835, p. 39).
In concluding his response to S. D. W., Strickland briefly noted that
his argument was not restricted to species names, but equally applied to
‘‘the proper names of genera, or of larger groups, where such groups are
retained unaltered.’’ And if a group was altered, Linnaeus’s aphorism
246 needed to be followed: ‘‘Where an old genus is divided into several
new ones, new appellations must, of course, be found for them; but,
even then, the original name should be retained for that group which is
the most typical of the whole’’ (Strickland, 1835, p. 39). It sounded
almost like Strickland reading out the Philosophia Botanica to a new
generation of taxonomists.
In spite of Strickland’s efforts, the radical reformists were not swayed
easily. When Strickland returned to the topic of nomenclature two years
after his initial bout of criticism, he noted to his dismay that ‘‘the lovers
of confusion have been hard at work,’’ and that ‘‘specific names are as
variable as the London fashions’’ (Strickland, 1837b, pp. 127, 128).
Once again, Strickland reminded the reformists that ‘‘[t]he meaning of a
name is … a point of less importance than its universality; and, when
the latter object has been once gained, would never sacrifice it to the
former’’ (Strickland, 1837b, p. 129). Yet by now he realized that
repeating this lesson over and over would not suffice. The ‘curse of
Babel’ posed by the proliferation of synonyms required a more
proactive effort on behalf of ‘‘the true friends of science to counteract this
evil tendency’’ (Strickland, 1837b, pp. 127–128). It had become high
time to compile a set of clear and authoritative nomenclatural rules, to
be accepted and followed by the entire taxonomic community. The
Philosophia Botanica was in need of an update, and Strickland took the
lead in getting the job done.
Just one month later, Strickland published a list of 22 provisional rules
of zoological nomenclature, which he compiled from the writings of
contemporary naturalists. Many of the rules he listed had ancestors in
Linnaean aphorisms.21 Rule 4, for example, articulated the ‘priority
principle’ of aphorism 243: ‘‘The first name given to a group or species
should be perpetually retained.’’ Rule 9 read: ‘‘It is desirable, but not
essential, that a name should have an etymological meaning.’’ Yet the list
was clearly provisional and incomplete. It did not, for instance, include
the equivalent of Linnaeus’s aphorism 246 that Strickland had mentioned
in his response to S. D. W. two years earlier. However, Strickland did
include another rule that tied the assignment of names to ‘typical’
elements: ‘‘Rule 18: The names of families and subfamilies should be derived
from the most typical genus in them’’ (Strickland, 1837c, p. 175).
21 Strickland later noted in correspondence that in his efforts to formulate
nomenclatural rules he proceeded by taking Linnaeus’ Philosophia Botanica and adapting it to
the demands of nineteenth century taxonomy (Strickland to Bonaparte, 30 May 1844,
Strickland’s adoption of this rule is interesting, since it amounted to a
partial departure from the purely nominalist spirit he had embraced
earlier. After all, Rule 18 effectively stated that a family name should in
some sense reflect the family’s content. Strickland indeed adapted this
rule from the writings of the reform-minded William Swainson
(1789–1855), who had argued for the improvement of certain names.
‘‘Before we impose a name upon a group which has never been
characterised, we should carefully analyse it; without which we shall run no
small risk of not discovering the typical character of the whole and
consequently apply a false name’’ (Swainson, 1836, p. 235). As an
example, Swainson mentioned that ‘‘[the genus] Muscicapa being more
typical than Todus, the family to which both belong should be called the
Muscicapidae.’’22 In Swainson’s view it would be ‘‘comparatively
trivial’’ to carry through changes like these for existing families. ‘‘While the
whole science is undergoing a revision and correction, it may be as well
to make these and every other necessary change of nomenclature at the
same time’’ (Swainson, 1836, p. 235).
Strickland’s inclusion of Swainson’s rule suggests that he was not
trying to push his nominalist philosophy at all costs and at all taxonomic
ranks. Since, ultimately, Strickland was seeking a way to stabilize names,
he may have been swayed by Swainson’s claim that this rule was
‘‘universally acted upon in Britain’’ (Swainson, 1836, p. 235). In any case,
Strickland soon started criticizing naturalists who failed to follow the
‘‘very convenient rule now generally adopted by naturalists, that the name
of a family should be compounded of the name of the most typical or best
known genus in it’’ (Strickland, 1837a, p. 605).
Yet, ‘convenient’ as this rule may have appeared, many taxonomists
would soon protest that it was far from clear how to apply it. What were
they supposed to understand by a ‘typical’ genus? typical of what, and
to whom? Assigning names on the basis of typicality judgments was far
more problematic than Strickland realized, and threatened to
undermine his aim of stabilizing names.
22 Swainson carried this change through in a later monograph, but not without
remarking that the name ‘Todus’ had meanwhile been determined to have been
misapplied, in such a way the correct name of the family might actually be ‘Todidae’ after
all! He nevertheless refrained from adopting the chain of nomenclatural changes that
followed from all this, since ‘‘these alterations would lead to so much confusion, that we
have not ventured upon, much less do we recommend, their adoption’’ (Swainson,
One problem with Strickland’s talk of ‘types’ and ‘typicality’ was raised in
an exchange with the Irish naturalist William Ogilby (1808–1873). When
Strickland criticized Ogilby for not following Rule 18, the latter
responded that he was ‘‘at loss to imagine’’ what this rule meant: ‘‘We hear
continually of the type of such or such a genus, and of typical species,
typical groups, and typical genera. Now if the word type be merely
synonymous with example, I see no objection to it, but on the contrary have
employed it in this signification myself: but it is notoriously employed by
others in a very different sense, and one to which I confess I can attach no
definite meaning’’ (Ogilby, 1838a, pp. 281–2 82).23
The ‘very different sense’ Ogilby referred to, was that of quinarians
like Swainson. As noted earlier (Section ‘‘Farber’s Taxonomy of Type
Concepts’’), the quinary theorists’ understanding of types or typical
elements was rooted in a particular theory of classification, on which
types were the most perfected members in a ‘grand system’ of nested
circles of taxa. Like all other conservatives, Ogilby was strongly
opposed to this speculative classificatory scheme. When he learned that
Strickland took his Rule 18 straight from Swainson, it must have
appeared to him that Strickland was importing quinary elements into his
Quick to recognize Ogilby’s worries, Strickland responded by
agreeing that ‘‘the quinary theorists attach to the word type, a deeper
and more mysterious meaning, but this is not the only one of their
doctrines to which I do not subscribe.’’24 In reality, Strickland’s
understanding of a ‘type’ was ‘‘precisely the same as Mr. Ogilby’s … By
‘the most typical genus’ of a family, I mean that genus which seems to
afford the best sample of the characters on which the family is based,
with the least tendency to diverge into other families.’’ The same
counted for the genus level, where the taxonomist selects ‘‘that species
which affords the fairest sample of the whole, [which] he calls a
type’’ (Strickland, 1838a, pp. 330–331).
23 Ogilby also protested against the idea of formulating nomenclatural rules in
general. He argued that they ‘‘make no part of zoology’’ and that there was no need to
strictly apply ‘‘these scientific thumb-screws, these verbal crucibles’’ (Ogilby, 1838b, p.
150). Strickland, of course, replied that rules of some form of regulation would be
necessary to get all naturalists to speak the same language (Strickland, 1838b).
24 At the British Association for the Advancement of Science meeting in Glasgow in
1840, Hugh Strickland also mentioned that ‘‘[a]ll systems, circular, quinary,
dichotomous, etc. are not natural, but artificial and only of use in arranging museums’’ (see
McOuat, 1996, p. 503, n.140).
Strickland’s response to Ogilby evinces that he did not intend to
make taxonomic nomenclature dependent on a particular taxonomic
theory, let alone on quinary theory. On the other hand, his response
does affirm that he considered the proper assignment of names to be
dependent on informed taxonomic judgment. To determine the correct
name of a genus or family, a taxonomist would have to be able to
identify its typical species or genus, respectively.
Yet this led to a further problem, raised by Charles Thorold Wood
(1777–1852) – ‘‘the most vociferous of the nomenclature radicals’’
(McOuat, 1996, p. 498). Wood pointed out that ‘‘it frequently happens,
that naturalists cannot agree on the type of the family: thus, Selby
pronounces the genus Sı´lvia to be the type of its family; Swainson says,
on the other hand, Re´gulus; and Blyth, rejecting both, adopts Fice´dula
as the typical genus … and so on throughout zoology’’ (Wood, 1836, p.
340).25 Moreover, Wood noted that aphorism 246 and its cognates were
vulnerable to the same problem:
Mr. Strickland observes, ‘‘Where an old genus is divided into
several new ones, new appellations must, of course, be found for
them; but, even then, the original name should be retained for
that group which is most typical for the whole.’’ This latter
proposition sounds well in theory, but will be found, on many
Wood (1836, p. 340)
Interestingly, the same line of criticism was voiced by a prominent
naturalist on the very opposite end of the radical-conservative spectrum.
John Obadiah Westwood (1805–1893) – ‘‘arguably the most vociferous
critic of nomenclature radicalism’’ (McOuat, 1996, p. 518) – illustrated
the problems with Swainson’s rule by highlighting that Swainson
himself sometimes ‘‘considered the wide geographical range of a form as
indicating typicality,’’ but at other times ‘‘opposes this principle, by
considering the preeminently typical form to … exist in a group of
confined geographic range’’ (Westwood, 1836, p. 563).
A decade earlier, Westwood had already diagnosed the root problem
with nomenclatural rules that depended on judgments about typicality.
The issue was not only that different measures of typicality could be
used, or even that judgments on a given measure depended critically on
subjective factors. The deeper problem was that even perfectly aligned
25 In The Ornithological Guide, Wood gave more examples of families for which ‘‘there
is difference of opinion with regard to which is the typical genus’’ (Wood, 1835, p. 75).
typicality judgments made at any time would be liable to change over
time, because of our evolving taxonomic knowledge. ‘‘Indeed, until the
contents of any particular family are clearly ascertained, the supposed
typical group will be continually subject to variation as new forms are
discovered, and hence, … the family name will necessarily be subject to
similar variation’’ (Westwood, 1828, p. 4).26
Westwood realized that the same lesson applied to any nomenclatural
rule that hinged on taxonomic judgment. Hence, like Wood, Westwood
also leveled his criticism at rules that descended from aphorism 246:
Fabricius, in his Philosophia Entomologica (p. 114) lays down the
following rule, ‘‘Si genus receptum secundum leges naturae et artis,
in plura dirimatur, tum nomen antea commune vulgatissimo insecta
manebit.’’ I do not know any method so likely to create confusion
and uncertainty as that contained in the above rule, since it is next
to impossible that every Entomologist would select the same
particular insect, and consider it as the most common in the family to
which it belongs.
Westwood (1828, p. 5)
Wood and Westwood’s criticisms put pressure on the Linnaean strategy
of using classification types to adjudicate on the application of names.
Both men realized that co-opting the Method of Type for nomenclatural
purposes would increase synonymy rather than reduce it.
Yet, as much as they agreed in their diagnosis of the problem, they
thoroughly disagreed about how to solve it. Wood took the radical
position that nomenclatural rules should be abandoned wholesale. The
establishment should stop trying to regulate nomenclature. Instead,
usage by taxonomists over time should be the standard for determining
the correctness of a taxon name. In his own work, Wood therefore often
gave ‘‘more than one name to the same family,’’ leaving his readership
to determine which of the names was ‘‘the best’’ (Wood, 1835, p. 74).
Westwood could not disagree more. He strongly favored the
institution of authoritative nomenclatural rules, and concluded that a
different set of rules would be needed to drive out synonymy. As
Westwood saw it, the problem with nomenclatural rules based on
typicality judgments was that they went against the grain of a principle that
26 As Hooker put it some years later: ‘‘The type of a group often turns out (on
extended knowledge of that group) to be the most aberrant form in it’’ (Hooker to
Darwin, 5 April 1844; DAR Letter 745). [I use ‘DAR’ to refer to Darwin’s
correspondence, collected in Burkhardt et al. (1985–).]
lection of the British Museum (Natural History). In the early twentieth
century, it was reported that ‘‘not a single specimen of bird from the
Sloane Collection now exists in the Museum. All have perished.’’ Many
other eighteenth century collections had similarly ‘‘fallen to pieces’’
(Sharpe, 1906, 79–80).46 Only with the invention and spread of reliable
taxidermic procedures around the 1830s could animal specimens be
preserved for more than a few years (Farber, 1977; Johnson, 2005).47
And yet, there was still a gigantic obstacle ahead. To actually
authenticate, isolate, label, preserve and store these specimens would
require considerable resources. Realistically, only large museums and
botanical gardens would have the people, facilities and funds to
undertake the effort. But what could motivate them to do so?
To answer this question, we need to return to John Edward Gray and
the British Museum. As I mentioned earlier, there is a sense in which his
innovative system of cataloguing removed the need to preserve original
specimens for use as fixed name-bearers. Using Gray’s system, species
names were anchored to individual pages, not to any of the specimens
listed on those pages. Nevertheless, Gray realized that there were good
other reasons to take special care of the large gatherings of original
specimens in the Museum’s collections. He was acutely aware that,
along with the catalogues, these specimens could be recruited to increase
the Museum’s power and prestige.
Gray sketched his attitude towards original specimens in the dozens
of catalogues that were published under his auspices from the early
1840s onwards.48 In each of these catalogues Gray included a brief
introduction in which he accentuated the ‘‘peculiarly fortunate’’
position of Museum as the recipient of many specimens on whose basis ‘‘the
species to which they belong were originally described, or … in which
they first received their names.’’ Gray emphasized that these specimens
were of special value, since ‘‘there can be no doubt of the specimens
being ascertained representatives of the names they bear’’ (e.g. Gray,
1843, p. vi; Gray, 1844, p. v). Gray’s introduction was sometimes
followed by a list of collections from which the Museum had acquired
these ‘type specimens,’ ‘types of the species,’ ‘original specimens’ or
‘authentic specimens,’ as he variously called them.
Gray’s commitment to preserving original specimens could already
be heard some years earlier, when he appeared before a Parliamentary
Committee that investigated the affairs at the BM in 1834. One of the
many questions fired at Gray was when, in his opinion, the Museum
ought to recognize a new species or genus which had been described in
print. Gray answered:
There is one test of the value of such divisions, the importance of
which is universally admitted, while it is seldom that an
opportunity is given to apply it; I mean the placing in the National
Collection type specimens of the objects described, authenticated by
their authors. Such specimens, with the names attached and so
authenticated, would always remain open to future investigators,
and would supply the deficiencies which occur even in the best
figures and descriptions, and which, by rendering doubtful what
has been done before, contribute much to embarrass science with
repetitions of the same object under new and varying names.
Parliamentary Papers (1835, §3345, p. 240)
The point about ‘authentication’ was essential. Not just any old
specimen, but only those specimens which had been used in naming and
describing species were of special value; even if they were not
representative of the typical characters of the species.
The latter point was also driven home by zoologist Nicholas A. Vigors
(1785–1840), when he appeared before the same Parliamentary
Committee two years later. Vigors was asked whether ‘‘A very inferior
specimen of the giraffe, for instance, would be valuable in a national collection,
if it were the first specimen introduced into Europe for the last 15
centuries?’’ He answered that there would be ‘‘nothing scientific’’ about
including it in the collection for mere historical reasons. ‘‘[B]ut if it was the
first specimen that had been described by a particular zoologist, I should
then, as a type of his description, and the very example from which he took
his characters, preserve it as most sacred’’ (Parliamentary Papers,
1836, §1315, p. 111). Vigors clearly understood ‘type’ in the sense of an
original specimen, and not in terms of a typical one.
The value that was attributed to these original type specimens is
underscored by the changing attitude towards ‘duplicates’ that started
to take hold. In Linnaean times, the notion of a ‘duplicate specimen’
had applied symmetrically: two collected specimens of the same species
counted as duplicates of each other, and any specimen in a set of
duplicates could be traded with another museum. This changed when
original specimens acquired a special status qua originals. A duplicate
specimen became a duplicate of the original specimen.
The difference in value between originals and duplicates was illustrated
by the remarks of anatomist John Flint South (1797–1882), yet another
scientist who appeared before the Parliamentary Committee. In a
backand-forth about the value of specimens in the collection, South told the
Committee that ‘‘it is useless load the Museum with four or five individuals
of the same species.’’ This prompted a question from a Committee member
about whether he considered it important ‘‘to preserve the identical
specimen first discovered as historical evidence … however inferior the original
specimen?’’ South: ‘‘Certainly; and in such case I consider it right that it
should be marked as the first specimen discovered, and by whom, and at
what date’’ (Parliamentary Papers, 1836, §§1156, 1175ff.; pp. 99–100).
Meanwhile, Gray developed a strategy to dispose of duplicates that
would simultaneously increase the value of the originals. He envisioned
the BM as a hub for the ‘authentication’ of specimens in a national
network of provincial museums and collections. The Museum’s original
specimens being the nomenclatural types, they could be used as
reference standards for labeling the duplicates in other collections. Gray
therefore proposed to the Trustees that the Museum to start selling
‘‘series of duplicates properly selected and named … to the different
local institutions’’ (Gunther, 1980, p. 221).49
Not all duplicates could be given away, though. Even the BM needed
duplicates to furnish its displays with, since original specimens were too
valuable for that purpose. ‘‘Such specimens ought especially to be
preserved in such a way as to be least liable to injury from exposure to
light, dust, or other extraneous causes of deterioration; and this is best
done by keeping them in a state least exposed to these destructive
influences, instead of in the open cases of a public and necessarily
strongly lighted gallery’’ (Gray, 1864b, p. 77).50 This required a shift in
49 McOuat (unpublished) has pointed out that this was part of Gray’s more general
program of middle-class reform. Gray wanted local institutions to compete on the ‘open
market’ for the acquisition of duplicates – a market for which the BM set the standards
through its nomenclatural type specimens.
50 The logician William Stanley Jevons (1835–1882) later reiterated Gray’s point,
stating that ‘‘by far the largest part of the biological collections should be packed in
draws, and only the most distinct and typical specimens exposed to view’’ (Jevons,
1883, p. 70).
mindset from that adopted ‘‘some forty years ago,’’ when curators had
thought it desirable to mount every specimen in the collections for
public display. Buttressing the new attitude towards original specimens
was a request for government funding Gray had made in the late 1850s,
for the purpose of storing ‘‘the type specimens described by various
authors, [as] they may be considered, in a scientific point of view, as
invaluable; and if these specimens are not very shortly removed to a
dryer place, they will be utterly destroyed’’ (Parliamentary Papers,
1858, p. 4).
‘‘A Crime Against Science’’
Gray’s efforts at the BM helped to spread the idea that original specimens
should be preserved, and should function as fixed anchors for species
names.51 Yet, much like in the case of type species and type genera, old
terminology obscured the new philosophy of type specimens. Gray
himself, for example, often alternated talk of ‘type specimens’ with talk of
‘typical specimens.’ In the mid–1850s, he reported with pride:
The extent to which the description of the Museum’s collection has
been carried on has rendered it the greatest store house of typical
specimens, from which very large numbers of species of animals of
all classes have been described, so that the consultation of the
collection has now become absolutely necessary to the naturalists
of all parts of the world, who may be desirous of extending the
domains of their science, and fairly knowing what has been before
recorded and described.
British Museum Annual Report, (1854); cited in Gunther (1975, p. 111)
Where Gray spoke of ‘typical specimens’ he was referring to the
nomenclatural type specimens. Undoubtedly, many of these specimens
possessed the typical characters of their species, and in this light his talk
of ‘typical specimens’ was warranted. But it was also confusing and
problematic, since even an indisputably atypical original specimen could
still serve as a nomenclatural type specimen. As long as a nomenclatural
51 A testimony to the importance of nomenclatural type specimens is a section on
‘Types in the Collection’ in an early twentieth century history of the zoological
collections at the BM. It mentioned that ‘‘the value of type-specimens, and the index which
their possession gives to the importance of a Museum, are now so universally recognized
that a few lines may be devoted the richness of the British Museum in this respect’’
(Thomas, 1906, p. 64). The same work also singled out J. E. Gray as ‘‘the real maker of
the collection’’ (p. 2).
type specimen could be placed reliably within the boundaries of one
species only, it could do its job of naming that species.
Gray was not an exception in using ambiguous language. Many
other naturalists similarly spoke of ‘type’ and ‘typical’ specimens
interchangeably and with different meanings. Joseph Dalton Hooker
noted about ‘type’ that ‘‘the word is often used in a vague and
unphilosophical manner: in the too frequent sense of the term it denotes
that individual of a species which was first cultivated, described, figured,
or collected, or that form which is most abundant in the neighborhood
of the writer’’ (Hooker, 1853, p. xvi).52
Hooker’s friend Charles Darwin (1809–1882) shared his scruples
about type talk. Having noted that ‘‘there is … so much vague in the
meaning of ‘typical forms,’53 he turned to Hooker and George Water
house (1815–1898) for help. They replied by concurring that the terms
‘type’ and ‘typical’ were being used equivocally, to refer either to (an
exemplar of) the most common form or to a most perfected one.54
Adding to Darwin’s confusion was a later letter from his botanist friend
Asa Gray (1810–1818), who remarked that ‘‘Our choice of what to take
as the typical forms very often is not free. We take, e.g. for one of them
the particular form of which Linnaeus, say, happened to have a
specimen sent him, and on which he established the species.’’ More generally,
Gray noted that ‘‘The form which first comes & is described & named …
sticks as the type, tho, in fact it may be far from the most common
form.’’55 At this point Darwin seems to have thrown in the towel,
writing to another correspondent of his that ‘‘with respect to Typical – I
observe that Naturalists use it in two very different senses; hence I have
almost entirely or entirely avoided its use.’’56
52 Moreover, Hooker considered none of these uses to capture the meaning of a
‘true type,’ which (to him) referred to ‘‘the originally created form of any plant.’’
About this form the naturalist could have ‘‘no clue whatever’’ since a plant’s past
typical state need not coincide with its present typical state. Hooker thus concluded
that, theoretically speaking, ‘‘the type is a phantom’’ (Hooker, 1853, p. xvi). In a
sense, Hooker herewith applied Wood’s and Westwood’s criticism of talk about
‘‘typicality’’ to the species level. (For more on Hooker on types, see Endersby (2008, p.
160ff.) and Stevens (1994, p. 150)).
53 Darwin to Hooker, 31 March 1844; DAR Letter 744; DAR Letter 1934.
54 Hooker to Darwin, 5 April 1844; DAR Letter 745; Waterhouse to Darwin, 26 april
1844; DAR Letter 748.
55 Asa Gray to Darwin, early August 1856; DAR Letter 1934. A little later Gray
repeated the same point in print: ‘‘Affixing of a name to a sufficient specimen in
distributed collections … [will] more surely identify the genus or species than might a brief
published description!’’ (Gray, 1864a, p. 279).
56 Darwin to Woodward, 6 March 1860; DAR Letter 2724.
The foregoing shows that, by the mid-nineteenth century, talk of
‘types’ and ‘typicality’ invited as least as much confusion at the level of
specimens as it did at the level of species and genera. Similarly, it was
only in the final decades of the century that the distinction between
classification and nomenclatural types was made more explicit.
Alphonse de Candolle was among the first to state clearly that ‘‘the
expression ‘type’ or ‘typical sample’ (echantillon typique) is … used
incorrectly for the specimen described by its author. One should say
‘authentic sample’ (echantillon authentique). Sometimes the first sample
described departs from the average, or the type of the species’’
(Candolle, 1880, pp. 51–52). In a discussion of Blanchard’s Re`gles (see p. 22)
at the 1889 International Congress of Zoology it was similarly remarked
that ‘‘we should clarify the meaning that is assigned to the word ‘type’
or ‘typus.’ Currently, this word is used in very different senses in the
everyday language of naturalist,’’ one of them being ‘‘the specimens on
which the first description of a species was based’’57 (Oberthu¨ r, 1889, p.
At the closing of the century, confusion over the meaning of the term
‘type specimen’ appears to have cleared. The generally recognized
definition of a type specimen as a fixed name-bearing specimen was now
clearly stated in journal articles and the prefaces of catalogues: ‘‘By a
‘type’ is meant the original specimen to which any generic or specific
name was first assigned’’ (Hughes, 1891). ‘‘A ‘TYPE SPECIMEN’ is the
specimen of an insect from which the original describer drew up the first
description of a species; and it is often of great importance to settle
disputed points of nomenclature … for if we are certain that we have the
original specimen before us, no further dispute is possible’’ (Kirby,
1892, p. 244).
The value of original specimens qua nomenclatural types was
similarly recognized clearly, in proclamations to the effect that ‘‘there can be
but one type [which] no museum can afford to part with … Typical
specimens are quite another matter, and the more distributed the better’’
(Lucas, 1897, p. 544). To treat a type specimen like any other specimen
had come to be seen as irresponsible, if not outright criminal: ‘‘The
exhibition in glass cases of type specimens of animals injured by light –
as birds and mammals – indicates a disinterestedness amounting almost
to criminal neglect’’ (Merriam, 1897, p. 732). It was equally ‘‘a crime
57 ‘‘Actuellement ce meˆ me mot, dans le langage ordinaire des naturalistes, est applique´
dans des sens tr e`s diff e´rents … On dit aussi: ‘la collection X contient beaucoup des
types,’ c’est-a` -dire d’e´ chantillons ayant servi a` la premier description d’une espe` ce.’’
58 For more on the discussion of Blanchard’s Re`gles, see Dayrat (2010, pp. 213–214).
against science’’ to remove the name tag from an original specimen and
to attach it to another one. A kind of crime which ‘‘in olden times little
thought was bestowed on.’’ Modern taxonomists, however, were
expected to recognize ‘‘the importance, I may almost say the sacredness,
of the ‘original label’’’ (Hartert, 1918, p. 5).59
In the early twentieth century, this understanding of type specimens also
began to make its way into a number of new nomenclatural codes. The
American Code of Botanical Nomenclature stated unambiguously that
‘‘the nomenclatorial type of a species or subspecies is the specimen to
which the describer originally applied the name in publication’’ (Arthur
et al., 1904, §14).60 The First International Rules of Zoological
Nomenclature included recommendations on the deposition of type
specimens in museums (ICZN, 1905).
However, just at about the time that the meaning of type specimens
as nomenclatural types seemed to have been anchored in nomenclatural
codes, the meaning of the term was strained once again. For, although
most taxonomists agreed that type specimens in the role of
namebearers ‘‘are of necessity unique’’ (Holmes, 1896, p. 56), a minority
began to use the term slightly more liberally.
The British, BM(NH)-based zoologist Oldfield Thomas (1858–1929)
already noted in the late nineteenth century that ‘‘The word ‘type’ itself
when first introduced was meant to refer to the particular specimen (in
the singular) originally described, but it soon was naturally applied to
any individual of the original series, if more than one specimen was
examined by the describer’’ (Thomas, 1893, p. 241). Thomas was of the
opinion that there was ‘‘little cause for confusion’’ in this extended use
of the term. Yet he noted that it did get problematic when ‘type’ was
given an even broader interpretation. Recently, authors had started
using ‘type specimen’ to refer to ‘‘any individual from the collection of
59 The enduring value of types is also illustrated by the complete segregation and
separate storage of type specimens that was being realized. When Britain declared war
on Germany in September 1939, over 85% of type specimens at the BM(NH) had
already been packed and readied for transport to the Zoological Museum at Tring
(Warren, 1966, p. iv).
60 However, the Americans failed to convince their European colleagues of the
importance of this paragraph at the International Botanical Congress held in Vienna, in
June 1905 (Arthur et al., 1907). Much to the chagrin of the Americans, the First
International Rules of Botanical Nomenclature continued to be modelled on de
Candolle’s Code from 1867.
the original author, obtained no matter how much later,’’ and to
specimens collected from the same locality as the original. These uses of
the term were ‘‘certainly liable to give rise to inconvenience and
confusion,’’ and needed to be cleared up. To do so, he suggested to
distinguish between five different kinds of type specimens:
A Type is a single specimen either unaccompanied by others at the
time of description, or else deliberately selected as such by the
author out of a series.
A Co-type is one of two or more specimens together forming the
basis of a species, no type having been selected. No species would
have both type and co-types, but either the former, or two or more
of the latter.
A Para-type is a specimen belonging to the original series, but not
the type, in cases where the author has himself selected a type. It
should, however, be one of the specimens mentioned or enumerated
in the original description.
A Topo-type is a specimen simply collected at the exact locality
where the original type was obtained.
On Thomas’ scheme, a type specimen was no longer simply a
namebearer; only one kind of type specimen now counted as a
namebearer. Type specimens of other kinds were in some sense ‘typical’ of
their species. Little did Thomas realize that this amounted to opening
Pandora’s box once again. Thomas’ attempt at clarification
threatened to reintroduce the problem of marrying taxonomic naming to
Soon, the pages of Science began to fill with suggestions for other
kinds of type specimens that needed to be distinguished, and with other
type-terms that needed to be added to Thomas’ list. The American
paleontologist Charles Schuchert (1858–1942), for example, suggested
to rename Thomas ‘type’ into ‘holotype,’ and introduced ‘plastotype,’ as
the term for an artificial specimen moulded directly from any of the
originally figured or described specimens. He mentioned that the latter
term could in turn be compounded into ‘hypoplastotype’ for a specimen
molded from a non-original specimen. Schuchert had clearly let go of
the idea that type specimens were name-bearers above anything else, as
he stated that ‘‘For a clear description of a new species a paleobotanist
may require as many individuals as there are specimens selected for
study, all of which are regarded as types’’ (Schuchert, 1897, p. 637; italics
Schuchert’s fellow countryman C. Hart Merriam (1855–1942)
protested against the ‘‘apparently incurable form of mania’’ among
naturalists who coined new type-terms. In an attempt to cure the disease by
an appeal to reason, Merriam emphasized the ‘old’ lesson that ‘‘type
specimens … should from the nature of the case be single, not multiple,’’
since ‘‘in a considerable percentage of the cases where several specimens
have been used as types, subsequent study has shown these specimens to
belong to different species. Is not this fact alone an unanswerable
objection to the existence of more than one type specimen of a species?’’
(Merriam, 1897, p. 732).
Schuchert could agree with Merriam in principle, but not in practice.
He admitted that although ‘‘the practice of selecting a single example as
the type … has its advantages, since all doubt is thus removed when a
new species is later found to contain diverse elements,’’ this advantage
was trumped by the fact that virtually no species ‘‘living or extinct, can
be defined from a single individual; hence a multiplicity of types is
generally a necessity’’ (Schuchert, 1905, p. 8). By now, Schuchert had
come to discriminate between no less than 18 kinds of type specimens
(Schuchert and Buckman, 1905).
In the years that followed, the terminology of types exploded. In
1933, a list of no less than 233 (!) type-terms was published (Frizzell,
1933), which included entries such as
Ironically, the author of the list mentioned that he had excluded
‘‘absurd terms’’ such as
para-adelfo-allopara-andro-lipo-mimo-paraedoeotype; a ‘hypothetical’ term for a specimen ‘‘that was included in the
original collection; was used as basis for the original description; that is
of the same sex (male) as the allotype [a specimen with the opposite sex
of the holotype]; shows the genitalia; is characteristically absent from
certain faunas; and is analogous to certain unrelated forms in other
countries’’ (Frizzell, 1933, p. 639).
When, in 1939 another list was published with ‘only’ 108 type-terms
that were (supposedly) actually being used (Fernald, 1939), two
prominent taxonomists stood up to reiterate Merriam’s objections,
aiming to end the avalanche of type terminology.
In Britain, the entomologist Carrington B. Williams (1889–1981)
mocked Fernald’s list by noting that he had found ‘‘no word in [it] for a
photograph of a cast of an abnormal larva of a worker of a social
hymenopteron, which has been compared with specimens from the same
locality as the type. It should, I believe, be:
‘‘Photo-plasto-terato-nepiono-ergato-homotopo-type,’’ but perhaps I am wrong’’ (Williams,
1940, pp. 623–624). More seriously, however, Williams made a plea to
restrict use of ‘type specimen’ to purely nomenclatural ends.
The object of the type is to eliminate from nomenclature the
possibility of human error, the personal equation, and private opinion
and this object is defeated if more than one type is designated. As
soon as a second specimen appears opinion is brought in. If I
designate ‘cotypes’ or ‘paratypes,’ or any of the hundred or so
others listed by Fernald, I imply my belief that these specimens are
co-specific with the type. My opinion may be sound or unsound,
but it is an opinion … As long as the original single ‘type’ exists,
such specimens as these can never be the final argument for
nomenclature. Always in them is expressed the scientific opinion of
the limits of a species and hence the possibility of uncertainty.
Williams (1940, p. 622)
In the U.S., the same lessons were spelled out at great length by George
G. Simpson (1902–1984), a rising star in paleontological taxonomy.
Simpson diagnosed the problem with the expansive type terminology as
stemming from the idea that ‘‘somehow there is a limited suite of
specimens that really represent or give rise to the species, hence must be
‘types,’ while others, although they belong to the species, do not and hence
are not ‘types’’’ (Simpson, 1940, p. 422). Yet, he continued, this
assumption was entirely unwarranted. A proper inference about the
boundaries of a species ‘‘should be based on all the available specimens
that are then considered as belonging to the species and on all of them
equally.’’ Whether a specimen had been described in the original
publication, or had been collected at a later data was irrelevant. All specimens
in the known sample should have equal weight in inferences about species
limits. ‘‘[T]here is no mystic virtue in ‘types,’ as such, that makes them any
better for comparison than would be any other member’’ (Simpson,
1940, p. 420). Hence, taxonomy could do entirely without the expansive
terminology of non-nomenclatural type-terms, ‘‘an irregular framework –
it cannot be called a system – that is approaching the fantastic’’ (Simpson,
1940, p. 421).
Simpson agreed with Williams that the only use for ‘type’ was that of
signifying a name-bearing specimen. He therefore proposed to retain
only those few compound type-terms that referred to name-bearing
specimens. This meant that apart from ‘type’ (or ‘holotype’) there
remained a use for such terms as ‘lectotype’ (a name-bearing specimen
selected from an original sample from which no holotype has been
selected by the first describer of the species) and ‘neotype’ (a substitute
name-bearer for a lost lecto- or holotype).61 All other type-terms could
easily be discarded.
The efforts by Williams and Simpson paid off. Almost twenty years
later, it was noted that ‘‘The whole scheme … of different kinds of types
… collapsed like a house of cards in 1940 when George Simpson
published his short but epoch-making paper on ‘Types in modern
taxonomy’’’ (Dunbar, 1959, p. 911; also see Romer, 1959, p. 919).62 Around
the same time, a small set of nomenclatural type-terms was also
included in the major nomenclatural codes that are still in use today,
such as the International Code of Zoological Nomenclature (Ride,
1999) and the International Code of Nomenclature for Algae, Fungi,
and Plants (McNeill et al., 2012).
In Linnaeus’s day and age there was little reason to anchor names to
fixed taxon elements. Names and classifications were ‘made’ and
disseminated from a few high seats, and were accepted on the authority of
their authors. Their status quo was upset by the nineteenth century
expansion of taxonomy, which saw a rapid increase in collected
materials, techniques, and, above all, practitioners. Existing classifications
were disrupted, and in the waves of change taxon names became afloat;
61 The notion of a ‘neotype’ raises further philosophical issues. For discussion of these
intricacies, see Simpson (1945), Haber (2012) and Witteveen (2015).
62 Meanwhile, Simpson himself continued to correct confused (or careless)
taxonomists who wrote things like ‘‘the closer the description [of the species] comes to
fitting the holotype exactly, the better the picture one can obtain of the typical specimen
of the species’’ (Shenefelt, 1959). Simpson response: ‘‘[T]ypes are not typical; description
of a specimen does not describe or define a species; and the proper function of a type
(‘holotype’) is solely that of name-bearing’’ (Simpson, 1960).
different authors started applying the same names to different taxa and
different names to the same taxa.
In the introduction to his Code, Strickland captured what had
happened, and what was at stake:
Restoring regularity required regulation. And even though
classifications could not be stabilized by decree, names could. Taxon names
could be stabilized by anchoring them to taxon-elements, so that even if
classifications would remain in a state of perpetual flux, each recognized
taxon would have a definite designation.
To this day, the hierarchical anchoring of family names in
genuselements, genus names in species-elements, and species names in
specimens, provides stability to naming in the face of ever-changing
classifications. Following this method, any two taxonomists can agree on the
correct name for any given taxon, regardless of their disagreements
about its limits.
It is an artifact of history that this method has become known as the
‘type method,’ despite the fact that name-bearing ‘types’ are not
required to be typical. It took some time for this message to sink in, but by
the mid-twentieth century it could be said that ‘‘no [taxonomist] will fail
to understand an author writing, e.g., ‘It is unfortunate that the
biological average of Planta vulgaris is poorly represented by the specimen
in the original publication.’ … It is manifest that the type-specimen and
the biological type of the same aggregate may thus be at odds’’ (Croizat,
1953, p. 124).
However, to the non-expert the notion of a ‘type specimen’ continues
to prompt unwarranted connotations of typicality. Even in news reports
for a journal like Science we still read that ‘‘as new specimens … are
found, they are deemed part of a known species, a new species, or even a
new genus based on how closely they resemble the type specimen’’
(Pennisi, 2001, p. 2304).
In an enduring effort to stamp out this confusion, taxonomists have
come up with various alternatives for ‘type’ that do not invite
associations of typicality: ‘standard element’ (Green, 1925), ‘testimonium’
(Dennler, 1939), ‘index,’ ‘nominal element’ (Williams, 1940),
‘onomatophore’ (Simpson, 1940), ‘nomenifer’ (Schopf, 1960), and
‘onomyphoront’ (Dubois, 2005). Ironically, taxonomy has thus been
burdened with numerous synonyms for a notion that was invented to
drive out synonymy.
And yet, none of these alternatives for ‘type’ have caught on.63 All
current nomenclatural codes and virtually all taxonomists continue to
speak of ‘types’ when they talk of name-bearers. What counts for taxon
names therefore also holds for the modern notion of a ‘type’: it does not
carry its meaning on its sleeve. Therefore, it needs constant reminding
that Whewell’s Method of Type and the modern type method are
similar in name, but not in nature. Whewell’s types represented nature,
our types represent names.
Most of the research for this article was done under the sponsorship
of Trinity College, Cambridge, and during visiting fellowships at the
Konrad Lorenz Institute of Evolution and Cognition Research, and
at the Descartes Centre for the History and Philosophy of the
Sciences and the Humanities. Their financial support is gratefully
acknowledged. Earlier versions of this paper were presented at
ISHPSSB 2013 in Montpellier, at &HPS 2014 in Vienna, and at the
‘The Artificial and the Natural’ workshop at Exeter University in
2014. I thank David Depew, Chris DiTeresi, Paul Farber, Jim
Griesemer, Matt Haber, Tarquin Holmes, Charlie Jarvis, Tim Lewens,
Gordon McOuat, Staffan Mu¨ ller-Wille, Greg Radick, Nicolaas Rupke,
Kees Rookmaaker, Sara Scharf, Laura Synder, and Polly Winsor for
their feedback, discussion, and encouragement. Special thanks go to
Ann Charlton from the Cambridge University Museum of Zoology,
for providing access to correspondence from the Strickland Papers in
the midst of renovations. I dedicate this paper to the memory of the
KLI’s scientific director, Werner Callebaut.
63 Some were not even intended to catch on. Immediately upon coining
‘onomatophore,’ Simpson (1940) already threw in the towel by saying: ‘‘As a matter of
practical usage, however, it is evident that the word ‘type’ is so deeply rooted in our
science that it is not desirable and probably not possible to uproot it’’ (p. 421).
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