PARTS OF ANIMALS, III. xiii.-xiv. 



their nature shares that of the blood-vessels : some 

 of them exist for the sake of the blood-vessels, 

 others do not exist apart from the blood-vessels. 



XIV. Below the diaphragm is the Stomach, which stomach 

 is placed where the oesophagus ends (if there is an intestines 

 oesophagus ; if not, immediately next to the mouth). 

 Next after the stomach and continuous with it is what 

 is called the Gut. 



It must be obvious to everyone why all animals 

 have these parts. It is a necessity for them to have 

 some receptacle for the food they take in, and to 

 expel it again when its moisture has been extracted 

 from it ; and there must be two different places for 

 these two things — the unconcocted food and the 

 residue ; there must also be another place in which 

 the change from one to the other is effected. Two 

 receptacles, then, one for the incoming food, one for 

 the residue which is no more use— as there is a 

 separate time for these so there must be a separate 

 place. However, it will be more appropriate to go 

 into these matters in our treatise on Generation and 

 Nutrition.'^ At the present we must consider the 

 variations that are to be found in the stomach and its 

 subsidiary parts. 



The stomach differs both in size and appearance in 

 different animals. Those of the blooded Vivipara 

 which have front teeth in both jaws have one 

 stomach ; e.g. man, the dog, the lion, and the other 

 polydactyls ; so also those that have solid hoofs, 

 e.g. the horse, the mule, the ass ; and those which 

 although they are cloven-hoofed have front teeth 

 in both jaws, e.g. the pig. These rules apply unless 

 the size of the frame and the character of the food 



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