111. 14 — 111. 15. 91 



quite worthless. . There is a jejunum in all animals, but it is only 

 plainly, visible in those of larger bulk, and in these only when 

 they have abstained from food for a certain time. For thus 

 alone can one hit on the exact period when the food lies half- 

 way between the upper and lower cavities ; a period which is 

 .very short, for the time occupied in the transition of food is 

 but brief In females this jejunum may occupy any part what- 

 soever of the upper intestine, but in males it comes just before 

 the caecum and the lower stomach.^^ 



(Ch. 15.;) The substance called rennet^ is found in all animals 

 that have a multiple stomach, but only in the hare'^ among 

 animals \yhose stomach is single. In the former the rennet 

 nefther occupies the large paunch, nor yet the reticulum, nor the 

 terminal abomasus, but is found in the cavity which separates 

 this terminal one from- the two first, namely in the so-called 

 psalterium,' It is the thick character of their milk which causes 

 all these animals to have rennet ; whereas in animals with a 

 single stomach the milk is thin, and consequently no rennet is 

 formed. It is this difference in thickness^ which makes the 

 milk of horned animals coagulate, while that of animals without 

 horns does not. Rennet forms in the hare because it feeds on^ 

 herbage that has juice like that of the fig. For juice of this 

 kind coagulates the milk in the stomach of the young animal. 

 Why it is in the psalterium that rennet is formed in animals 

 with multiple stomachs has been stated in the Problems.^ 



676 a. 



