40 NILS HJ. OÜHNER 



whole genital apparatus from the specimens sectioned, and found 

 its construction as reproduced in fig. 15. 



The hermaphrodite gland, which occupies the large portion of 

 the body, is situated on the dorsal side of the posterior liver 

 duct, as pointed out by Alder & Hancock. It consists of a 

 compact mass of follicles, thus differing from that of some other 

 cladohepatic nudibranchs such as Bornella, Scyllaea, Dirona, 

 where the gland is divided into separate lobes. The gland has 

 the general structure with female folliculi in the extreme ends 

 of the branches and male ones towards the central trunks. 



. From the hermaphrodite gland a short duct debouches into 

 a wide ampulla [amp.), which was filled with spermatids. The 

 duct again narrows and finally bifurcates into a very short oviduct, 

 which immediately opens into the glandular portion of the vesti- 

 bulum. From this part there issues also a long-shafted recep- 

 taculum seminis (r. s.), the mouth of which, however, is separa- 

 ted from that of the real oviduct by a fold of the wall, thus 

 forming the ludiment of a special vaginal opening. 



The 'mucus gland {m) consists of many lobes; a smaller 

 part opens separately into the vagina. The walls have athickepithe- 

 lium partly deeply coloured with haematoxylin, and showing mucous 

 contents, partly less tinged, thus representing an albuminiparous 

 portion of the gland. Thus these two are united into one mass. 

 The male apparatus is of a more complicated structure, as it is 

 furnished, not only with a prostata (pr.), but also with a vesi- 

 cula seminalis (v. s.). These two are attached close to each 

 other and near the point where the vas deferens separates from 

 the hermaphrodite duct. The vesicula seminalis is a bladder 

 composed of some diverticula, of which a dorsal one is the 

 largest. The prostata is a lengthened, somewhat winded, coecum 

 with an epithelium of elevated secretory cells with basal nuclei 

 and a grained plasma. At the blind end of the coecum there 

 is attached a small bladder-like appendage lined with narrow 

 elevated cells which have a central nucleus, and bear cilia with 

 a thick basal membrane. 



