i6o Notes, ii. 3 — 4. 



immediately, but are stored up in the body, as fat {D. G. i. 18, 59). It is in the first 

 sense that plants are said to have no excrement ; in the second that seeds are sometimes 

 (iv. 10, 17) regarded as representing the residual matter. . 



9. A. means sponges. There are numerous microscopical animals capable of active 

 locomotion, and yet without intestinal cavities ; but such were of course unknown to 

 Aristotle. ' . • 



10. The comparison occurs again in iv. 4, 4. Elsewhere A. compares the roots of 

 plants to the mouth of an animal, "being the channel by which they take food from the 

 ground" {De Juv. et Sen. I, 7), and yet again (Z>. G. ii. 7, i) to the vessels of the 

 umbilical cord. 



11. Cf. iii. 5, Note 5. A. knew nothing of the lacteals. But not long after his time, 

 Erasistratus, his pupil, opening a sucking kid (cf. Galen, An Sanguis in art. ch. 5), saw 

 many small white vessels in the mesentery. He noticed that these did not, like the 

 blood-vessels, pass to the liver, and also that they were in connection with certain 

 glandular bodies, the mesenteric glands. He supposed rightly enough that the contents 

 of these white vessels were derived from the milk swallowed by the kid ; that is he 

 recognised their absorbent character. But Galen {De Usu part. iv. 19) held that their 

 office was to nourish the intestines. Erasistratus's observation seems to have led to no 

 further result, and to have been quite forgotten. Thus the discovery had to be made 

 again nearly 2000 years later (a.d. 1622) by Aselli of Cremona. 



12. H. A. i. 16, iii. 4. 



13. The argument is as follows. The entire food, digestible or not, has a receptacle, 

 viz. the stomach ; and the indigestible part of it also has a receptacle, viz. the lower 

 abdominal cavity or large gut ; the digestible portion must therefore also have a 

 receptacle, inasmuch as it is separated from the indigestible part. But there is no other 

 receptacle than the blood-vessels ; which must therefore be the receptacle of the nutritious 

 portion. And as these blood-vessels are seen to contain nothing but blood, the blood and 

 the nutritious matter must be one and the same thing. 



14. After a meal the amount of blood is even as much as doubled according to 

 Bernard {Lemons, 1859, i. 419). 



15. The argument is to the following effect. Neither is the entire food sensitive ; nor 

 the excremental part of the food ; nor yet the nutritious part of it, even after it has been 

 converted into blood. It is only when the blood has been farther converted into flesh, 

 that it becomes sensitive. Up to that time it is insensible ; for though it is in immediate 

 contact with the flesh, yet it has therewith no anatomical continuity whatsoever. 



16. A. often refers to a treatise which he was going to write on Nutrition. It has been 

 generally supposed that the De Generatione, in which nutrition is handled to a certain 

 extent, is the treatise thus promised. But this view seems incompatible with the fact 

 that a similar reference to a future treatise "on growth and nutrition" is made in the De 

 Generatione itself (v. 4, 4), in a passage which appears to have been overlooked. The 

 present passage moreover speaks of "other writings" besides the De Generatione. The 

 promised treatise is not extant ; perhaps was never written ; for no mention of such is 

 to be found in Diogenes I-aertius. Heitz {Die verlor. Schrift. d. Arist. 61) thinks it 

 probable that a shott separate treatise was written, such as those massed together in the 

 Parva Naturalia ; and that some portions of it have come down to us merged in the De 

 Generatione. And thei-e is in fact in the De Somno (3, 4) a passage which apparently 

 refers to a treatise on Nutrition as already written. 



(Ch. 4.) 1. The coagulation of the blood is considered in two other passages {H. A. 

 iii. 6; iii. 19). In all of these places A. speaks distinctly of the coagulum as being 



