CHAPTEK VII. 



ON PLANTS. 



There are many passages in Aristotle's works which 

 show that he contemplated writing a separate treatise on 

 plants, and it is probable that he wrote a treatise of this 

 kind. No work on plants, however, which can be assigned 

 with confidence to Aristotle has been found. There is a 

 small Aristotelian treatise entitled Be Plantis, considered by 

 some to be one of Aristotle's genuine works, but usually 

 admitted to be spurious. The only genuine sources from 

 which his views on plants can be obtained are, in fact, a 

 large number of passages which occur, almost incidentally, in 

 some of his works, particularly his History of Animals, Parts 

 of Animals, Generation of Animals, De Anima, and the 

 Parva Naturalia. It will be best to consider these passages, 

 before discussing further the Aristotelian treatise on plants. 



The passages in which Aristotle distinguishes plants 

 from animals on the one side, and inanimate matter on the 

 other, have been referred to already in Chapter v. There 

 it will be seen that, according to him, plants have only the 

 lowest form of vital principle — the nutritive, that they do 

 not move from place to place, but exhibit movements due to 

 growth and decay, and that they have no sensory faculty, 

 although they are affected in some way by certain external 

 influences. 



These views, compared with those of Anaxagoras, 

 Empedocles, Democritus, and Plato, on the nature of the 

 vital principle of plants, are less fanciful, and indicate a much 

 more practical and reasonable conception of plant life. It is 

 clear from the Timceus and from fragments from Anaxagoras 

 Empedocles, and Democritus, such as, for example, some 

 which are given in the Aristotelian treatise, De Plantis, i. 

 cc. 1 and 2, that they believed that plants had sensation and 

 cognition, that, in fact, they were capable of feelings of joy 

 and sadness. 



The consideration of the nature of the vital principle, or 



