THE APPENDAGES OF THE TESTICLE. 



1949 



to the well-established end-plexuses on the external surface of their membrana pro- 

 pria. The existence of intratubal nerves, however, needs further evidence. 



Epididymis 



Appendix testis 



Remai 

 of caiia 



THE APPENDAGES OF THE TESTICLE. 



Under this heading are included several vestigial structures that remain for a 

 variable period, some throughout life, as more or less conspicuous bodies attached to 

 the testis or to the epididymis. They claim attention not only on account of their 

 interesting morphological relations, but also since they may become the seat of 

 cystic and other pathological changes. The most important are ( i ) the appendix 

 testis, (2) the appendix epididymidis, (3) the paradidymis, and (4) the vasa aber- 

 rantia. 



The appendix testis, often called the tinstalked or sessile hydatid, is a small 

 but fairly constant body (being present in over 90 per cent, according to Toldt) 

 from 5-10 mm. in length and less than half as much in breadth, fixed to the upper 

 pole of the testis close to or slightly overlaid by the globus major (Fig. 1650). The 

 term ' ' hydatid' ' is inappropriate, since the body is solid and not vesicular and its 

 form is irregular. Its free end often 



presents a shallow, funnel-like de- Fig. 1661. 



pression surrounded by a dentated 

 margin, the whole suggesting the 

 fimbriated end of the oviduct in minia- 

 ture, a resemblance supported by the 

 embryological significance of the ap- 

 pendage as the remains of the cranial 

 end of the Miillerian duct (page 

 2038) overgrown and enclosed by 

 connective tissue. In structure the 

 appendage consists of a vascular con- 

 nective-tissue stroma in which lies 

 embedded a minute canal, of variable 

 size and extent, lined with columnar 

 epithelium. Usually the canal ends 

 blindly, but in exceptional cases it 

 may open on the free surface. 



Inconspicuous additional appen- 

 dages of the rete testis have been 

 described by Roth and by Poirier, 

 which consist of blind tubules that 

 extend from the testicle into the lower 

 end of the globus major, either lying 

 buried within the latter behind the 

 testis or projecting as small elevations on the free surface. They probably represent 

 the remains of Wolffian tubules that failed to retain their connection with the canal of 

 the epididymis (Wolffian duct). 



The appendix epididymidis, or stalked hydatid, much less constant than the 

 sessile one (27 per cent, according to Toldt), appears as a small pyriform body (from 

 3-4 mm. in length) attached to the upper pole of the globus major (Fig. 1650). 

 This appendage is variable in form, size, and number (since two or more may be 

 present), and corresponds with the pedunculated hydatid in the female, both bodies 

 probably being derived from anlages of the tubules of the Wolffian body, although 

 their origin is still a subject of discussion and by some referred to the Miillerian 

 duct. 



According to Toldt, an additional minute body {lower paradidymis), consisting 

 of a single convoluted tubule, is sometimes found, even in aged subjects, behind the 

 head of the epididymis, but in front of the veins. It may be isolated, connected with 

 the canal of the epididymis, with the rete testis, or with both, these variable relations 

 being explained by its probable nature as an efferent duct that has become com- 

 pletely or partly disconnected. This tube is frequently the seat of cysts which, 



Serous 

 membrane 



Testis 



Sagittal section of appendix testis. X 25. 



