THE URO-GENITAL SYSTEM 



183 



the cloaca, and like the ovarian mass, in its active state, pushes 

 the abdominal viscera downward and toward the right side. 



Structure. — The oviduct consists of three coats: first, the serous, 

 located on the outside, which is a reflection of the peritoneum; 

 second, the muscular middle tunic; third, the mucous coat, which 

 in a resting state is thrown into folds. 





Fig. Sp. — The active oviduct of a hen laid open, i, The ovary. 2, The 

 funnel. 3, The albumin secreting portion. 4, The isthmus. 5, The shell gland 

 portion. 6, The vagina. 7, The superior ligament. 8, The inferior ligament. 



Parts of the Oviduct. — The parts of the oviduct are as follows: 

 the funnel, the albumin-secreting portion, the isthmus, the shell- 

 gland portion, or uterus, and the vagina (Fig. 59). 



The funnel is the trumpet-shaped portion, the ostium tubae 

 abdominale, whose mouth or fimbriated opening faces the ovary, 

 and lies ventrally to receive the ovum, or yolk, as it is discharged 

 from the ovary. Its thin wall, expanded in the anterior portion, 

 is provided with fimbriae-like projections. This funnel-shaped 

 portion soon converges to form a constricted portion. This por- 

 tion of the active oviduct is from 3 to 4 centimeters long. The 

 mucous membrane occurs in folds forming low longitudinal spiral 



