THE QUINARY SYSTEM. 
xlvii 
arranged all animals into vertebrated^ or tliose having an internal 
articulated spine ; and invertehrated^ or those having external arti- 
culations ; * but M. Geoffroy St. Hilaire has carried the same ana- 
logies into such minute detail, that they become not a little 
ludicrous. He finds, for example, not only that the mem- 
braneous lungs of birds are analogous to the swim-bladders of 
fishes, but also to the posterior wings of insects. He tries farther 
to make out an analogy between the various pieces of the crust- 
aceous shell of crabs and lobsters, and the joints of the spine (ver- 
tehrm) of quadrupeds. From the spine he proceeds to the ribs, 
which it is natural, in such a system, to expect will make their way, 
like the vertebrae, to the outside of the body; and accordingly 
he states, that what we ignorantly suppose to be the legs of crabs 
and lobsters, are, in fact, the ribs, which, by some inexplicable 
process or transition, have pushed themselves out to the exterior, 
and have assumed the office of legs ; while what ought to have 
been the legs have become jaws, f and are actually called feet- 
jaws (Pieds-mdclioires^ Cuvier; Pattes-mdclioires^ Savigny.) 
Kirby and Spence, adopting this view, argue, that because one pair 
of the eight legs in spiders, &c, [Araclinida) originate in the head, 
and not in the trunk, though they perform the office of legs, they 
are not, therefore, entitled to be called legs ‘Gn a primary 
sense ;” but apparently represent the feelers or the lips of insects.f 
Pursuing a similar fancy, M. Savigny, with great ingenuity 
and skill, it must be allowed, endeavoured to show that the 
suckers of butterflies and the tongues of bees correspond with the 
jaws of beetles and crickets. § He has reasoned so plausibly, 
indeed, that most naturalists are led to think him right, even in 
oppos^ition to the obvious fact of the jaws being separate and 
moveable, while the suckers are united, and their parts immove- 
able. I have already remarked, that the argument would be 
equally plausible if it were reversed ! 
These views require only to be stated, in order, I conceive, to 
demonstrate their fanciful foundation to every unbiassed mind; 
and Baron Cuvier has shown good sense in strongly opposing 
* Prodrome d’une Nouvelle Distrib.,Biill. des Science, 1816. 
I Philosopliie Anatomiqiie ; and duart. Jour. For. Med. for 1821, p. 35. 
X Intr. iv. 395-6. § Mem, des Anim. sans Vertebres, pt. i. 
