tes.

STONES.
Figured stones.
Crystals.

SALTS.
Vitriols.

METALS.

HALF-METALS.

SULPHURS.
Bitumens.

EARTHS.
Pure earth.

WATER.

AIR.

FIRE.

More subtile matter.

The nature of the transitional forms which he inserts between his
principal classes show very clearly his entire lack of morphological
insight--the transitions are functional. The positions assigned to
clothes-moths and corals are very curious! The whole scheme, so
fantastic in its details, was largely influenced by Leibniz's
continuity philosophy, and is in no way an improvement on the older
and saner Aristotelian scheme.

Robinet, in the fifth volume of his book _De la nature_ (1761-6),
foreshadows the somewhat similar views of the German
transcendentalists. "All beings," he writes, "have been conceived and
formed on one single plan, of which they are the endlessly graduated
variations: this prototype is the human form, the metamorphoses of
which are to be considered as so many steps towards the most excellent
form of being."[23]

The idea of a gradation of beings appears also in Buffon (1707-1788),
but here it takes more definitely its true character as a functional
gradation.[24] "Since everything in Nature shades into everything
else," he says, "it is possible to establish a scale for judging of
the degrees of the intrinsic qualities of every animal."[25]

He is quite well aware that the groups of Invertebrates are different
in structural plan from the Vertebrates--"The animal kingdom includes
various animated beings, whose organisation is very different from our
own and from that of the animals whose body is similarly constructed
to ours."[26]

He limits himself to a consideration of the Vertebrates, deeming that
the economy of an oyster ought not to form part of his subject matter!
He has a clear perception of the unity of plan which reigns throughout
the vertebrate series.[27] What is new in Buffon is his interpretation
of the unity of plan. For the first time we find clearly expressed the
thought that unity of plan is to be explained by community of origin.

Buffon's utterances on this point are, as is well known, somewhat
vacillating. The famous passage, however, which occurs in his account
of the Ass shows pretty clearly that Buffon saw no theoretical
objection to the descent of all the varied species of animals from one
single form. Once admit, he argues, that within the bounds of a single
family one species may or