122 MEMOIR OF CUVIER. 



tliat the classification as well as explanation of facts could be founded only on 

 tlieir inmost nature tliorouglily understood. In a word, and taking into view 

 only the natural history of animals, that branch of natural history in general 

 Avhich M. Cuvier has most directly elucidated by his labors, it is evident that 

 what had been wanting to Linnaeus and to BufFon, whether for the classification 

 of animals or for the proper explanation of their pheiiomena, was the adequate 

 knowledge of their.internal structure or organization ; and it is not less evident 

 that the laAvs of all classification, as of the whole natural philosophy of these 

 beino-s, could spring only from the laws of that organization itself. 



It will presently be seen that it was by the assiduous study of these fruitful 

 laws that M. Cuvier renovated in succession zoology and comparative anatomy ; 

 that he renovated them one by means of the other; and that he founded on both 

 the science of fossil animals — a science altogether ncAv, wholly due to his genius, 

 and which has thrown light in its turn on the science of the earth itself. But 

 before we come to these last and astonishing results, the fruits of so many grand 

 conceptions and so many unexpected discoveries, let us first see what he has 

 done in particular for each of the sciences just mentioned, in order that we may 

 afterward be better able to comprehend and embrace in a general view what he 

 has done for all. I commence with zoology. 



Linnaeus, who of all the naturalists of the eighteenth century had exerted the 

 most general influence on the human mind, particularly in point of method, 

 divided the animal kingdom into six classes : quadrupeds, birds, reptiles, fishes, 

 insects, and icorms. In this Linnaeus committed a first general error, for in 

 placing in the same line these six primitive divisions, he assumed that an equal 

 interval separated them one from another ; than which nothing could be less 

 exact. On the other hand, almost all these classes, especially the last, at one 

 time separate animals the most nearh' related, at another unite those which are 

 most incongruous. In a word, classification, which has no other end but to 

 mark the true relations of beings, in this instance almost everywhere severed 

 those relations ; and that instrument of method W'hich only serves the under- 

 standing in so far as it conveys just ideas of things, communicated to it, nearly 

 tiirougliout, only false ideas. 



This whole classification of Linnaeus was, therefore, to be recast, and nearly 

 the entire framework of the science to be reconstructed. Now, to attain this 

 end, it was first necessary to found the classification on organization, for it is 

 organization alone which gives the true relations ; in other terms, it was neces- 

 sary to found zoology on anatomy ; , it was next necessary to introduce into the 

 method itself views more just and elevated than had been previously applied. 

 It w'as, in effect, these elevated views as regards method, these profound studies 

 on organization, which shone forth in the first labors of M. Cuvier : potent 

 resources, by means of which he succeeded in efiecting successively the reform 

 of all the branches of zoology, one after the other, and in finally renovating iu 

 its whole extent that vast and grand science. 



I have said that it was chiefly in the class vermes of .Linnaeus that disorder 

 and confusion prevailed. He had thrown into it all animals with white blood — 

 that is to say, more than half the animal kingdom. It was in the first of his 

 memoirs, published in 1795, that M. Cuvier pointed out the great difference of 

 the beings till then confounded under this vagae name of white-l)looded animals, 

 and that he separated them with precision from one another, first into three great 

 classes : Molluslcs, which, like the poulp, the cuttle-fish, the ouster, have a heart, 

 a complete vascular system, and respire by means of brancliiaj or gills ; insects, 

 which have, in place of a heart, only a simple dorsal vessel, and respire by 

 trachea? ; and, lastly, zoophytes — animals whose structure is so simple as to have 

 gained them this name, signifying animal plants, and which have neither heart, 

 nor vessels, nor distinct organ of respiration. By subsequently forming three 

 other classes — vermes, Crustacea, cchinodermata — all the animals with white 



