51 209 



vestibiilum genitale adds still 2 mm to the length; on the outside the seminal vesicle is seen 

 in the middle with its duct that turns down with many windings; before the former the 

 prostata, and before the latter the penis with the seminal duct is found. The duct of the 

 hermaphrodite gland forms at the middle of the inside a not thick, and not long, some- 

 what twisted ampulla; at the navel of the back side of the prostata this ampulla divides 

 into the ovigerous and the seminal duct. The ovigerous duct is rather long, twisted, up 

 to the last third part somewhat thicker (forming, however, no «fanshaped organ»), and 

 opens at the thick end of the duct of the seminal vesicle beside the albuminous gland. 

 The globular, yellowish prostata (fig. J Ob), which is quite finely granulated on the surface, 

 has a diameter of 3"5 mm ; it has a strong navel on the hinder side, a less pronounced one 

 on the fore side; from the latter issues the powerful seminal duct (fig. 10 a), of a diameter 

 of 6 mm and a length of ll mm . This duct opens into the top of the penis, which has 

 a length of 8 mm by a diameter of 2 mm . The penis (fig. 10 d) is inversely conical, somewhat 

 compressed; the praeputium is thin, and its cavity is quite filled by the strong, also some- 

 what compressed, conical glans, through which the seminal duct runs directly to its 

 pointed, refolded end. The seminal vesicle (fig. 10a) is bagshaped, S™" long, its con- 

 tents were semen; the winding, powerful duct was wider below, it opened in at the base 

 of the duct of the mucous gland. The mucous-albuminous gland was grayish and 

 whitish; the efferent duct passes into the vestibiilum genitale (fig. 10 c) by a shallow 

 narrowing. 



Beside the animal was found a large spawn, which Dr. Mortensen regards as per- 

 haps arising from it. The spawn forms a large heap of a diameter of 3 - 5 cm , composed of 

 the innumerable windings of a dull yellow tube of a diameter of 0"75 mm . The tube con- 

 tained inside of the tough, transparent covering several, between each other displaced 

 series of more or less cleft eggs 1 ). 



If the form of the cowl does not originate in mutilation, we have here a new 

 species; on a contrary supposition the animal examined here would perhaps belong to the 

 Melibe papulosa (de Filippi). 



Fam. Aeolidiidae. 

 Subfam. Plabellinidae. 



Comp. R. Bekgh, System der nudibranch. Gasteropoden. Malacolog. Unters. Heft. \VIII. 1892. p. 1033. 



') Accordingly the spawn would be rather different from that of the Tethys. Comp. Lo Bianco, notizie 

 biologiche. Mittheil, aus d. zool. Station zu Neapel. VIII. 18S8. p. 42t. 



D. K. D. Vidensk. Selsk. Skr., 6. Raikke, naturviden sk. og mathem. Aid. XII. 2. 27 



