THE REPRODUCTIVE SYSTEM OF E. SUPERBA 



333 



The flexure increases in length and thickness, and in addition a swelling appears on 

 It forming a lateral pocket, anterior to the point at which the duct bends outwards over 

 the ventral musculature (Fig. 3). At the same time, the growth of the liver in a posterior 

 direction alters the position of the testis, so that the latter comes to lie more closely and 

 completely on the lobes of the liver (Figs. 1-7). 



A second flexure afl (Fig. 4) appears at a short distance behind the junction of the 

 vasa deferentia with the testis, at the point where the vasa deferentia are most widely 

 separated from one another, before they come to lie close together in a median position. 



Fig. 5. Dissection to show the development of the male reproductive system, x 15. afl, anterior flexure; 

 ej, ejaculatory duct; g, gut; Ip, lateral pocket; pfl, posterior flexure; /, testis; sps, spermatophore sac; 

 vd, vas deferens. 



This anterior flexure is bent first outwards and then inwards again. The vasa deferentia 

 are also more swollen behind the external genital apertures. 



The follicles of the testis increase in size until they are closely crowded together, 

 hiding the horseshoe-shaped band. Both the anterior and posterior flexures grow 

 larger, the vasa deferentia begin to show coiling, while the lateral pocket Ip is more 

 marked (Fig. 5). 



Coiling extends gradually over the whole length of the vasa deferentia between the 

 anterior and posterior flexures. At the same time, the walls of the ducts become 

 thickened, especially in the region of the lateral pockets Ip. At this stage there is often 



