216 MARSHALL— A STUDY OF THE 



[June 19, 



side of the gizzard at the base of the proventriculus, and consists 

 of four distinct divisions : 



1. The duodenum {Duo., Figs. 6, 9, 15) makes up the entire 

 first loop. It extends from the pylorus almost to the posterior end 

 of the stomach. It then bends anteriorly, and at the edge of the 

 right liver lobe passes over into the small intestine. The duodenum 

 is about 43 mm. in length. 



2. The small intestine (Figs. 12, 15) lies between the duodenum 

 and the insertion of the caeca. It measures about 85 mm. 



3. The terminal intestine (Figs. 12, 15) extends from the in- 

 sertion of the caeca to the anus and is very short. Anteriorly 

 the diameter is very small but posteriorly it is dilated at the cloaca. 

 Its length is about 18 mm. Thus the entire length of the main in- 

 testine from pylorus to anus is 146 mm. The intestine consists of 

 three closed loops of which the duodenal is the first in course. 

 The ascending branch of the third loop and the following portion 

 of the small intestine are covered by the first and second loops. 

 The descending branches of the second and third loops are to the 

 left of their respective ascending branches. The intestinal ar- 

 rangement agrees with the iso-orthoccel type of intestine as defined 

 by Gadow (/. c. ). 



4. Two cozca (Co?., Figs. 12, 15) are present. They are quiet 

 long and the terminal half of each almost equals the small intestine 

 in size. At about one third the length of the caeca from their inser- 

 tion there is on each a constriction, and at this point the diameter 

 is less than in any part of the alimentary tract. From tip to inser- 

 tion the caeca measure about 35 mm. 



Filling the duodenal loop is a pale, slender organ, the pancreas 

 (Pan., Figs. 6, 9, 15). It consists of two branches, the main 

 branch occupying the position mentioned. Extending beyond the 

 edge of the ascending branch of the duodenum is the smaller division. 

 The pancreas has two ducts (Pan. d. ), both coming off on the dor- 

 sal surface. The larger duct, which comes from the main portion, 

 arises proximal to the branching off of the smaller part, and run- 

 ning anteriorly close to the descending part of the loop of the duo- 

 denum enters its ascending branch just about where it begins to 

 curve along the right liver lobe. The small duct comes from the 

 smaller division on its inner edge at a point about one third the 

 length of that division from its anterior end. 



