HISTOLOGY 



157 



forms the stratum vasculosum. This in turn is surrounded by longitudinal, 

 smooth muscle fibers. A serous membrane covers the horns and connects 

 them with the broad ligaments. 



As the horns come together the structure of the fused walls changes, 

 losing first the longitudinal muscle layers and later the strata vasculosum. 

 The circular muscle layers persist farther but disappear gradually and the 

 two lumina are separated only by a wedge-shaped septum composed of 

 longitudinal smooth muscle and connective tissue. Finally, the two lumina 



— Epidermis 



Dermis 



~ Clitoral gland 



■* — Hair follicle 



Capsule 



Fig. 81. — Clitoral gland of a two weeks old mouse. (X25.) 



join to form the single lumen of the corpus uteri. Laterally on each side 

 of the corpus uteri the lumen of the vagina forms a deep fornix, while the 

 mid-dorsal and mid-ventral walls of the corpus are fused with the wall of 

 the vagina (Fig. 80). The corpus uteri opens into the vagina at the cervix, 

 which is dorso-ventrally flattened. The epithelium of the corpus uteri 

 consists of low cuboidal cells changing to stratified squamous at the cervix. 

 A few shallow glands are present in the mucous membrane. The lamina 

 propria is more fibrous and not as cellular as it is in the uterine horns. 



Vagina, clitoris and clitoral glands. — The wide, dorso-ventrally flattened 

 lumen of the vagina is lined by stratified squamous epitheHum which 

 undergoes cyclic changes during estrus. The lamina propria is formed of 



