36 INTESTINE AND DIET OF REPTILES. 



Thrynocephalus, Uromastix and Fhri/nosoma. In the latter 

 the ventricle is fuUy crescentshaped, its p^doric tract being re- 

 curved to the median line. A distinct fundus-sack I have 

 only observed in Ämblyrhynclms in wbich perhaps the food 

 requires a prolonged treatment , in the acid juice of the ven- 

 tricle (conf. below). From the pylorus which, as is evident 

 from the description above, usnally is situated far back and 

 nearer the left side, the small intestine makes some 

 coils which are differently arranged in accordance with 

 the length of the organ and the shape of the animal and its 

 abdominal cavity. The small intestine finally opens into the 

 proximal end of the large intestine. Typically the latter is 

 situated along the right side of the abdominal cavity. In 

 long and slender forms with short intestine it takes a more 

 median position. In such forms again where the herbivorous 

 diet requires a prolonged large intestine it is doubled up on 

 itself. But that is not only the case in such lizards. The 

 large intestine is, just as well as other organs, dependent on 

 the shape of the abdominal cavity and it is therefore also 

 bent back upon itself in short and broad lizards like Phry- 

 nocepJialiis, Trojndurus, Phrynosoma a. o. This curving of 

 the large intestine invariabh'' takes place towards the me- 

 dian side so that the colic portion, so to say, lies on the me- 

 dian or left side of the rectal part of the large intestine which 

 retains its position at the right side of the abdominal ca- 

 vity. 



In such cases as when the large intestine is bent back 

 upon itself a colon and a rectum can be rightly spöken of, 

 even from a morphological point of view, but when the colon 

 is short and not fully distended there is as a rule a tem- 

 porary constriction dividing the large intestine into a colic 

 and a rectal portion which have different functions from a 

 physiological point of view although the morphological diffe- 

 rence is only slight or not at all visible. 



The opening of the small intestine into the large one 

 takes place in a diiferent manner in different forms so that 

 sometimes a coecum or excentric dilatation is formed some- 

 times not. In the Geckonids it seems to be the rule that 

 the small intestine opens excentrically into the large one. 

 Usually the said opening is situated more or less on the 

 right side or ventridextrally and then a sinuous dilatation 



