DISTINCTIVE CHARACTERS OF ANIMALS. 155 



tinguished by the make of the foot, as being of three kinds, undivided, 

 cloven, and digitated, or severed into toes or cJaws.* 



These indeed were mere hints, and only intended as such ; but they 

 were truly valuable and important ; for they roused zoologists to that ge- 

 neral comparison of animal with animal, which could not fail of very es- 

 sentially advancing the cause of natural history ; and have, in different 

 degrees, laid the foundation of almost every methodical arrangement which 

 has since been offered to the world. 



To run over a list of these arrangements would be equally useless and 

 jejune. The writers who have chiefly signalized themselves in this de - 

 partment, are Gesner, Aldrovandi, Johnston, Ray, Linneus, Klein, Lace- 

 pede, Blumenbach, and Cuvier ; and in particular sections of it, Lamarck, 

 Bloch, Fabricius, Latreille, and Brogniart ; all of whom have flourished 

 since the middle of the sixteenth century ; most of whom have contri- 

 buted something of importance to a scientific method of studying and 

 distributing animals ; and the most celebrated of whom are Ray, Linneus, 

 and Cuvier. 



The system of Ray is derived, in its first outlines, from that recom- 

 mendation of Aristotle, which suggests an attention to the different struc- 

 tures of different descriptions of animal life ; and his observation that one 

 of these differences consists in their possessing lungs and sanguineous 

 systems, or their being destitute of lungs and exsanguineous. 



The Linnean method is, for the most part, built upon this general ar- 

 rangement of Mr. Ray, especially in regard to quadrupeds ; it is, how- 

 ever, an extension of it, and certainly an improvement. That of M. Cu- 

 vier, in its subordinate division, is founded upon both these ; but in its 

 primary and leading distinctions, upon the nervous or sensorial, instead of 

 upon the respiratory and sanguineous system ; all animals upon M. Cuvier's 

 scheme, being primarily divided into vertebrated and invertebrated ; those 

 furnished with a back-bone, or vertebral chain, for the purpose of enclosing 

 the spinal marrow, and those destitute of such a chain : the secondary 

 sections, consisting of vertebrated animals with warm blood, and verte- 



I brated animals with cold blood ; invertebrated animals with blood-vessels, 



j and invertebrated animals without blood-vessels. 



All these, under his last modification, which is that subjoined to hislec- 



i tures on Comparative Anatomy,! are regarded as embracing nine distinct 

 classes ; as I. mammals, and 11. birds, which belong to the warm-blooded 

 vertebral division. 111. amphibials ; and IV. fishes, which belong to 

 the cold-blooded vertebral division ; and the five following, which fill up 

 the division of invertebral animals. V. molluscous ; soft-bodied marine 

 animals, or mostly marine animals, as oysters ; limpets ; whelks ; cuttle- 

 fish : pipe- worms or ship-worms ; defended by a testaceous covering, VI, 

 CRUSTACEOUs ; as crabs ; various lobsters ; shrimps ; sea-spiders ; and the 

 monoculus tribes. VII. insects ; being all those ordinarily so denomi- 

 nated. VIII. worms, embracing along with those commonly so called, 

 leeches, and various sea-worms with bristles on the sides of the body, as 

 aphrodites, terebels or naked ship-worms, serpules, amphitrites, nereids, 

 tooth-shells. IX. zoophytes : the term being used very extensively, so 

 as to include, not only all the zoophytes of plant-like animals of Linneus 

 and other naturalists, but all their infusory, wheel, or microscopic animals ; 



* Arist. Hist. Anina. lib. i. cap. 1, cap. 3. cap. 6. 



t Lecons d'Anatomie Conaparee de G. Cuvier. Svc. 4 torn. Paris, 180o. 



94 



