Species

88 Species

have a common root, and can assume that originally they all sprang from this root, of

which one is reminded by the large number of their shared similarities; and these related

species probably have separated only through the inuence of climate, food, and the pro-

cession of years, which brings into being every realizable combination and allows every

possibility of variation, perfection, alteration, and degeneration to become manifest.^180

He held at the end of his career the view that species were denite categories, and
that one might determine the boundaries by seeing experimentally whether repro-
duction was possible; he reported such in his essay “Mulets” (1776) of the sterility
of hybrids as a mark of species boundaries.^181 But as what he meant by espèces was
more like Linnaeus’ genera, or even the later family rank, he was not fussed about
using the Linnaean terminology inconsistently, occasionally shifting from one term
to another, perhaps deliberately to annoy the Linnaeans, or perhaps doing exactly
what Theophrastus had done, using the terms informally. Local variant forms for
him were more geographical varieties than they were species, which was the pre-
miere souche (rst stock). Moreover, he believed that these varieties were closely
related to similar forms in the Old as in the New World. It was a kind of vicari-
ance denition of species; Stresemann gives the example of Buffon putting shrikes
(gen. Lanius) into a single species with species from Senegal (Tch agra senegala),
Madagascar (Leptopterus madagascarinus), and Cayenne (Thamnophilus doliatus)
as climatic variations.^182

Adanson: Many Characters Are Needed

Michel Adanson (1727–1806) was a student and intimate of Antoine-Laurent de
Jussieu’s uncle, Bernard, and for a time lived with the de Jussieu family. He laid out
a taxonomic procedure that derived from Bernard’s ideas in his Family of plants
(Familles des Plantes^183 ) in which he attempted a natural system in which all char-
acters are to be used equally to uncover groups. He wrote

It was necessary to seek in nature for nature’s system, if there really was one. With this

aim, I examined plants in all their parts, without omitting one, from roots to embryo,

folding of leaves in the bud, manner of sheathing, development, position, and folding of

the embryo and radicle in the seed relative to the fruit; in a word, a number of features

to which few botanists pay attention.^184

He allowed, where Ray and Linnaeus had not, the use of microscopic characters
in classication. Adanson was later claimed, somewhat illicitly, as a precursor to
the so-called “phenetics” school of classication,^185 but unlike the pheneticists of
the 1960s, he did not hold that all characters have equal weight in classication, but

(^180) Stresemann 1975, 56 translating page 75 in the original.
(^181) Roger 1997, 327.
(^182) Stresemann 1975, 57.
(^183) Adanson 1763.
(^184) Morton 1981, 303.
(^185) Nelson 1979, Winsor 2004.