240 SPECIAL HISTOLOGY. 



definitively proved, and it is very possible that Miiller, in this 

 respect also, may still be right. The art. helicince, therefore, 

 are not simple vascular loops, as which they are described by 

 Arnold, although, in one instance, I have noticed such an 

 arrangement in place of them.] 



§ 202. 



Physiological remarks. — The development of the testes, com- 

 mencing in the second month, takes place, according to all that 

 we know, from a blastema which appears independently on the 

 inner side of the Wolffian body; and, at first, the form of the 

 male sexual glands entirely resembles that of the ovaries. At a 

 subsequent period, when the Wolffian body begins to waste, a 

 portion of its fine canals, the Malpighian corpuscles of which dis- 

 appear, become connected with the testis, and are formed into 

 the epididymis, whilst at the same time the excretory duct of the 

 Wolffian body constitutes the vas deferens} Then, by a process 

 not as yet accurately explained, the testis, with its peritoneal 

 investment, descends into the scrotum under the agency of 

 the gubernaculum, a process composed of transversely striated 

 and smooth muscles ; and by the growing together of the peri- 

 toneal protrusion contained in the gubernaculum — the processus 

 vaginalis peritonei, — with its own proper serous coat, acquires 

 its tunica vaginalis propria. The vesicula prostatica, the ana- 

 logue of the uterus, and probably of the vagina, is the remainder 

 of the " Miillerian ducts," two canals, descending on the ex- 

 ternal border of the Wolffian body, which, in the female, form 

 the oviduct and by the coalescence of their extremities, the 

 uterus and vagina; but in the male disappear, except the 

 commencement, which becomes the " hydatids of Morgagni," 

 and the last portion. The vesiculce seminales are protrusions 

 of the v. deferentia ; and the prostate, Cowper's, and the smaller 

 glands, are most probably formed, in analogy with other similar 

 glands, from the epithelium of the urethra. The penis is 

 developed from the pelvic bones outwards, and does not, till 



1 [It is a curious fact connected with this alleged origin of the epididymis dis- 

 tinctly from the rest of the gland, that, in cystic disease of the testicle, either of the 

 innocent or malignant type, the affection is " the result of morhid changes in the 

 ducts of the rete testis ; this part of the gland being the sole seat of the disease." 

 (Curling, « Med. Chir. Transact./ XXXVI, p. 456, 1853.)— Eds.] 



