228 



MANUAL OF HISTOLOGY. 



The arrangement of the glandular elements is similar to 

 that in the racemose glands, and consists of excretory ducts ter- 

 minating in glandular vesicles or acini. The ducts which have 

 their orifices in the urethra at its prostatic portion, and upon 

 its inferior wall, are here lined with a transitional, or, when 

 large, with a pavement epithelium, which gradually changes 



f 



Pia. 104. Transverse section through the caput gallinaginia : a, epithelium of surface; b, vesicula 

 prostatica ; c, epithelium of the vesicula ; <j, muscles ; e, ejaculatory duct ; /, excretory duct of the pros- 

 tatic glands ; 0, upper wall of the urethra ; muscles running vertically. From a child. Klein. 



into a columnar variety as the ducts penetrate the organ. The 

 basement-membrane is structureless, and is invested by a mus- 

 cular layer. | The acini are also lined by a columnar epithelium 

 and possess a structureless membrana propria ; their shape is 

 usually pyriform, and they have a diameter varying between 

 0.1254 and 0.23 mm. The epithelial cells of the acini frequently 

 contain granules of brownish pigment. 



