194 THE REPRODUCTIVE SYSTEM. 



present. The submncosa is a layer of loose connective tissue 

 containing rich vascular plexuses, a sort of erectile tissue. 

 The muscular coat consists in general of an inner circular 

 and an outer longitudinal layer of involuntary muscle. The 

 outermost coat is fibrous, or areolar, connecting the vagina 

 with the bladder anteriorly and with the peritoneum, rectum, 

 and perineum posteriorly. Among the nervous elements of 

 the vagina are special sensory terminals. 



The vulva is covered with an integument continuous with 

 the mucous membrane of the vagina and urethra and with 

 the external skin. This integument consists of stratified 

 squamous epithelium, in places pigmented, resting on a papil- 

 lated tunica propria, beneath which is a loose areolar sub- 

 mucous layer. 



Opening on the surface are numerous small glands, both 

 mucous and sebaceous ; the latter occur not only on the hairy 

 portions of the labia majora, but also on the iabia minora 

 unassociated with hairs. 



The glands of Bartholin are two macroscopic racemose 

 glands, corresponding to Cowper's glands of the male, situated 

 in the labia minora, one on each side of the outlet of the 

 vagina. Special sensory nerve-terminals occur in the mucous 

 membrane in this region. 



Beneath the integument of the labia majora are masses of 

 adipose, areolar, vascular, and muscular tissue ; beneath that 

 of the labia minora and vestibule is an especial abundance of 

 vascular plexuses and sinuses, forming an erectile tissue. In 

 the deeper strata of the genitalia are fasciculi of muscle, both 

 striated and non-striated, variously arranged. 



The hymen is a fold of the vaginal mucous membrane. 

 The clitoris repeats in a rudimentary way the cavernous and 

 erectile structure of the penis. 



The Mammary Glands. 



The mammary glands are fully developed only during their 

 periods of functional secreting activity, the periods of lacta- 

 tion; at other times they are in an atrophic non-secreting 

 condition. 



When in the state of active secretion the mammary 



