820 THE MALE GENITAL TBACT. 



lining columnar epithelium sends prolongations into the connect- 

 ive tissue the glandular nature of which is not generally 

 agreed upon, as some observers claim these formations to be 

 merely sinuosities of the mucosa. The epithelia contain a vary- 

 ing number of brown pigment-granules. Three layers of smooth 

 muscle-fibers are discernible. Similar structures are found in the 

 walls of the seminal vesicles. The ejaculatory ducts are covered 

 with ciliated columnar epithelia (authors do not mention the 

 cilia), and the muscle-layers are said to be only an inner longitu- 

 dinal and an outer circular. Toward the opening at the summit 

 of the seminal hill, the epithelia gradually change into a stratified 

 formation composed of several layers. In this situation the 

 mucosa has numerous sinuous veins, agreeing with the general 

 structure of the male urethra. 



(5) As remnants of embryonal formations are considered: 



The paradidymis (Giraldes), which consists of single or multiple lobules 

 at the vascular porta of the testis, between the blood-vessels of the spermatic 

 cord ; each lobule being composed of convoluted tubules, with a blind termi- 

 nation, and lined with ciliated columnar epithelia. It is considered to be a 

 remnant of the primordial kidney (Wolff's body), being homologous with the 

 parovary of the female. 



The vas aberrans Hatter i and the vasa aberrantia of the rete testis (M. Roth) 

 are blind tubules, kindred in structure to the tubule of the epididymis and the 

 tubules in the corpus Highmori. Both are remnants of the genital portion of 

 Wolff's body. 



The liydatid of Moryayni is a non-pediculated lobule at the anterior aspect 

 of the testis, immediately in front of the head of the globe. It is composed 

 of vascularized connective tissue, and covered with ciliated epithelia, which, 

 according to E. Fleischl, send prolongations into the depth of the hydatid. 

 The center holds a canal, which is lined with ciliated epithelia ; this canal 

 may be widened into a vesicle, and, if in communication with the tubule of 

 the epididymis, is found filled with semen (Luschka). It is considered as an 

 analogy of the ovary. 



The pedunculated hydatid is not constant ; it is a vesicle the size of a 

 millet-seed, attached to the head of the epididymis by means of a slender 

 pedicle. It is a remnant of the embryonal Miiller's duct (Krause). 



(6) The prostate gland surrounds the initial portion of the 

 male urethra, mainly at its posterior and lateral circumference. 

 It is composed of acinous glands, which exhibit numerous con- 

 volutions, and are lined with cuboidal epithelia in several layers. 

 The acini are sometimes small in comparison with the large 

 ducts, which are lined with columnar epithelia; sometimes 

 the acini are imperfectly developed, and the ducts seem to rep- 

 resent chiefly the glandular structure. In the acini, not infre- 



