Chap. xxxi.] THE MALE GENITAL ORGANS. 253 



sists of an inner and outer longitudinal and a middle 

 circular stratum. The ganglia in connection with the 

 nerve-trunks of the adventitia are very numerous. 



334. In the ductus ejaculatorii we find a lining of 

 columnar epithelial cells ; outside of this is a delicate 

 mucosa and a muscular coat, the latter consisting of 

 an inner thicker longitudinal and an outer thinner 

 circular stratum of non-striped muscular tissue. 



When passing into the vesicula prostatica the 

 columnar epithelium is gradually replaced by stratified 

 pavement epithelium. 



335. (4) The prostate gland. Like other 

 glands, the prostate consists of a framework and the 

 gland tissue proper or the parenchyma. 



The framework, unlike that of other glands, is 

 essentially muscular, being composed of bundles of 

 non-striped muscular tissue, with a relatively small 

 admixture of fibrous connective tissue. The latter 

 is chiefly limited to the outer capsule and the thin 

 septa passing inwards, whereas the non-striped mus- 

 cular tissue surrounds and separates the individual 

 gland alveoli. 



336. The parenchyma consists of the chief ducts, 

 which open at the base of and near the colliculus 

 seniinalis, and of the secondary ducts, minor branches 

 of the former, which ultimately lead into the alveoli. 

 These are longer or shorter, wavy or convoluted 

 branched tubes with numerous saccular or club-shaped 

 branches. The alveoli and ducts are limited by a 

 membrana propria, have a distinct lumen, and are 

 lined with columnar epithelium. In the alveoli there 

 is only a single layer of beautiful columnar epithelial 

 cells, the substance of which is distinctly and longi- 

 tudinally striated. In the ducts there is an inner 

 layer of short columnar cells, and an outer one of 

 small cubical, polyhedral or spindle-shaped cells. 



At the mouth of the ducts the stratified pavement 



