THE URO-GENITAL SYSTEM 1 89 



anteriorly in such a manner that they aid in forming the serous 

 ovarian pocket, which guides the yolk into the fimbriated portion, 

 or funnel, of the oviduct. The walls of the ovarian pocket are 

 formed by the left abdominal air-sac, a part of the intestine, and 

 the mesentery. The dorsal portion is formed by the roof of the 

 abdominal cavity, and the ventral portion is formed by the dorsal 

 wall of the air-sac. The medial, the anterior, and the lateral limit 

 of the pocket are formed by a fusion of the wall of the air-sac to 

 the mesentery and to the body wall. Posteriorly, the wall consists 

 of the transverse part of the small intestine and the caudal portion 

 of the left caecum with their attached mesentery. 



