PLANTS, AND INANIMATE MATTEE. 93 



homoeomeria are materials, some of which may be consti- 

 tuent tissues. 



It is evident from Aristotle's definition of homceomerion 

 and anhomoeomerion that his views were dependent to some 

 extent on the way some words were used by the ancient 

 Greeks. This causes some difficulty in a few cases. He 

 explains that some constituent parts of animals may be 

 considered to be homoeomeria, if their material only is 

 considered, or anhomoeomeria, if the functions are taken 

 into account, and that the only reason for classifying skin, 

 membrane, nail, horn, &c., with the homoeomeria is that the 

 name of any one of them happens to be used to denote a 

 part of it also.* 



Considerations based on the homogeneity of the parts 

 do not appear to be important in Aristotle's views on the 

 homoeomeria ; for instance, he says that they may vary in 

 themselves, and that blood, which is one of the best defined 

 of his homoeomeria, may be of varying degrees of consist- 

 ency, turbidity, and temperature, even in the same animal.! 



The terms " homoeomeria " and " anhomoeomeria " 

 appear to be Aristotle's own, but the distinction involved in 

 their use had been expressed by Plato, in Protag. xviii., 

 where he prefers to consider justice, temperance, and holi- 

 ness to be parts of virtue in the same sense as the mouth, 

 nose, and eyes are parts of the face, rather than that they 

 are like parts of a block of gold, which differ from the 

 whole and from one another only in size. 



Aristotle's third degree of composition may now be 

 considered. The homoeomeria are combined to form the 

 anhomoeomeria, of which he gives many examples, such as, 

 for instance, the face, eye, tongue, arm, foot, wing, and the 

 heart and other chief viscera. These show that his anhomoe- 

 omeria are parts having definite forms or functions. This 

 is in accordance with his own statements. He tells us that 

 the heart, like the other chief viscera formed of vascular 

 material, is of the nature of a homceomerion, but is also an 

 anhomoeomerion, because it has a definite form.t Again, 

 his anhomoeomeria may be characterized by possessing a 

 capability of performing work, of doing something. § 

 Generally speaking, his organic anhomoeomeria are members 

 or organs of the body, and he considered the bodies of some 



- P. A. ii. c. 9, 6556. | Ihid. ii. c. 2, 647i. 



I Ihid. ii. c. 1, 647a. 



§ H, A, i. c. 3, ss. 2 and 3 ; P. A. ii. c. 1 ; G. A. i. c. 18, 7226. 



