Aristotle s History of Animals. 67 



and possess the sense of touch ; but these two "characters are 

 tlie only ones that are indispensable, and one cannot find a third 

 that is not wanting in some species. . 



Of the land animals, there is none that is fixed to the ground ; 

 of the aquatic animals, on the contrary, several are known. 



Every animal which has wings has also feet. The author, 

 on the faith of this general observation, denies the existence of 

 the dragon, which was represented as a winged serpent. 



Of the winged insects, several are furnished with stings. 

 Those which bear that organ at the anterior part never have 

 more than two wings ; those which bear it at the posterior part 

 have four. 



Propositions like these, it is well known, cannot be laid down 

 a priori : they are necessarily founded upon the minute obser- 

 vation of facts, and suppose a very general observation of ani- 

 mals. 



In this introduction, Aristotle lays the foundation of his clas- 

 sification. He divides animals into those which have blood, and 

 those which are destitute of it : in other words, he separates the 

 red-blooded animals from the white-blooded. The red-blooded 

 animals are quadrupeds, serpents, birds, fishes, and the cetacea. 

 Although the last two classes live equally in the water, and re- 

 semble each other a little in their external structure, Aristotle 

 is far from confounding them, when he places them near each 

 other. He was as well acquainted with the nature of the ceta^ 

 cea as we are at the present day. He knew that they are 

 warm-blooded animals, which bring forth living young, and 

 nourish them with milk from their mammae. He also proposes 

 a very distinct separation among the quadrupeds, between the 

 viviparous and oviparous. The latter, he says, have a great 

 resemblance to serpents, in the internal organization and tegu- 

 mentary system. In this method, the dift'erent groups are 

 formed in a very natural manner, and it is only in their arrange- 

 ment that some improvement is to be made. 



The white-blooded animals are the moUusca, crustacea, tes- 

 tacea, and insects. This division is certainly not without fault ; 

 but no better one was proposed until the time of Linnaeus. Of 

 the mollusca, Aristotle designates in jiarticular the cuttle-fisli, 

 the octopus, the loligo, and the argonaut ; and remarks, that 



