-C or some time, I liave now and then, when other more pres- 

 sing work has perniitted my so doing, studied the morpholo- 

 gical structnre of the intestine of reptiles belonging to difFer- 

 ent groups. These studies are not yet finished or complete. 

 I think, liowever, that the following notes may show them- 

 selves to be of enough interest to be published now as a pre- 

 liiuinary commnnication and in a certain respect they may 

 be regarded as complementing the investigations I have be- 

 fore made concerning the, to the diet adaptive structure of 

 the intestine of sorae maramals.^ 



In the following I have considered the general shape 

 arrangement and length of the intestinal canal especially 

 the cEecum of some lizards belonging to difFerent families. 

 The measurements have been made with a thread along the 

 intestine while still as much as possible adherent to the me- 

 sentery. In severai instances the material was in no good 

 condition and it might therefore happen that the measure- 

 ments are not so exact as could be wished, but on the whole 

 I think the general result may be considered satisfactory. 

 To make the measurements comparable some standard must 

 be used to show the relation betvveen the length of the in- 

 testine and the bulk of the animal. As the length of the 

 tail is extremely difFerent in difFerent species the total length 

 could not be used, but instead of this I have chosen the di- 

 stance from the snout to the vent or cloacal aperture a mea- 

 surement that always can be taken with full certainty. But 

 even this does not always give the true relation, if, for in- 

 stance, short and broad forms like Phrynosoma are compared 

 with long and slender ones like Mhineura. Nevertheless if 

 the difFerence in shape is born in mind severai conclusions of 



1 Proc. Zool. Soc. 1902. 



