PARTS OF ANIMALS, IV. x. 



the blooded viviparous animals. Some of the parts 

 Mhich we have already enumerated still remain to 

 be described, and we will take these first. This 

 done, we will describe similarly the blooded Ovipara. 



We have already " spoken of the parts around the External 

 head, and what is called the neck, and the throat. I'.looded 

 All blooded animals have a head, but in some of the animals. 

 bloodless ones the head is indistinct {e.g. in crabs). " ^^^^^ 

 All Vivipara have a neck, but not all Ovipara : to 

 be precise, only those which breathe in air from with- 

 out and have a lung. 



The presence of the head is mainly for the sake of Sead and 

 the brain. Blooded creatures must have a brain, 

 which (for reasons aforeshown) ^ must be set in some 

 place opposite to the heart. But in addition, Nature 

 has put some of the senses up in the head, apart from 

 the rest, because the blend of its blood is well pro- 

 portioned and suitable for securing not only warmth 

 for the brain but also quiet and accuracy for the senses. 

 There is yet a third part which Nature has disposed of 

 in the head, viz. the part which manages the intake 

 of food ; it was put here because this gave the best- 

 ordered arrangement. It would have been impossible 

 to put the stomach above the source and sovereign ^ 

 part, the heart ; and it would have been impossible 

 to make the entrance for the food below the heart, 

 even with the stomach below the heart as it actually 

 is, because then the length of the body would be 

 very great, and the stomach would be too far away 

 from the source which provides motion and concoc- 

 tion. These then are the three parts for whose sake 

 the head exists. The neck exists for the sake of the 



" At 655 b 27—665 a 25. ^ At 652 b 17 ff. 



365 



