REPRODUCTIVE ORGANS IN ANIMALS 



31 



beneath, constitutes the mucous membrane. This contains a 

 number of glands which open into the central lumen, and are 

 furnished with a secretory epithelium similar to that lining the 

 lumen. The glands are especially active during pregnancy, 



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■ ■ % C^ 



\ 



a^ 



c. 





^-l 





CO 







Fig. 20. — Transverse section through normal uterus of rat. 

 (From Marshall and Jolly.) 



when they secrete a nutrient fluid sometimes called " uterine 

 milk." The stroma is a primitive connective tissue containing 

 blood vessels. Outside of the stroma are the unstriated muscle 

 layers (circular and longitudinal). On the outside of all is the 

 serous or peritoneal lining. 



