Q74 SUPPLEMENT 
the second. We should also observe that the class of multi- 
valves is still worse handled than in any other system. As to 
the genera, those of the univalves, though very few in num- 
ber, are pretty well characterized by the form of the aperture ; 
but it is not so with those of the bivalves, in which there is no 
reference made to the hinge. In fact, d’Argenville has almost 
always followed Lister; and when he has not, he has done 
mischief. He has often strongly criticised him, and always 
erroneously. 
Immediately after d’Argenville comes another entirely sys- 
tematic writer, who has not the advantage of having given 
good figures. This is Klein, who has almost invariably 
attached himself to changing every thing which Linnzus 
attempted to establish. He published, in 1753, a new system 
of conchology. He comprehends them all in the teste, which 
he divides into cochlides, conche, niduli testacet, echnioder- 
mata, and finally into tubuli, or marine tubes. Under the 
name of cochlides he understands the turbinated shells, which 
he divides into two sections: simple cochlides, which he de- 
fines to be a spiral canal, resulting from a single circumvolu- 
tion of the shell, and composite cochlides, which are those in 
which the circumvolutions of the shell appear double ; so that 
the testa seems to be composed of two cochlides. Although 
his definitions are bad enough, we can see that the first sec- 
tion comprehends the spirivalve shells which have not their 
aperture terminated by a siphon, or rather the last whorl of 
which is not terminated in a point like the spire; and that he 
understands, on the contrary, by his composite cochlides, those 
which are pointed in front as well as behind. Although this 
consideration is evidently new, it is clear that it conduced but 
little to a good division. Another innovation of Klein is his 
having separated, one cannot well tell why, the conchs, 
conche, into monoconchs, which are the patelle and. the 
neighbouring genera; and into diconchs, diconche, which 
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