CLASSIFICATION OF OLEACINID^. XXV11 



Ferussacia in external anatomy, so far as the published ac- 

 count goes. Unfortunately its dentition and genitalia are 

 unknown. 



ORYZOSOMA. 



This genus is anomalous in having a distinctly perforate 

 axis. The early whorls are irregularly coiled, as in some 

 species of Streptostyla. Von Martens would apparently 

 place the group among the Ferussacida, but he had not seen 

 specimens. I believe it will prove to be related to Streptostyla 

 when the living animal is found. See p. 163. 



STREBELIA. 



The small Bulla-like shell of two whorls sits Testacella- 

 like near the end of the comparatively large body. Conic 

 labial processes are developed. The pharynx is very large, 

 as usual, the radula being longer than the shell, with about 

 6,17,1,17,6 teeth of the usual form. Genitalia without acces- 

 sory appendages, the penis-retractor inserted on the epi- 

 phallus. The duct of the spermatheca is much shorter than 

 the oviduct, thus differing from other Oleacinidcz. The ana- 

 tomy has been fully worked out by Strebel. Only one species 

 known, S. berendti (Pfr.), Vol. I, p. 22. 



This genus is the only Oleacinoid form in which the shell 

 shows marked degeneration. 



