GASTEROPODA. 



Sub-genus : — Taheitia, H. and A. Adams, 1863. 



Type, Truncatella porrecta, Gould, Taheiti. Operculum 

 shelly, furnished with erect radiating lamellae. Aperture of shell 

 ovatt ; last whorl separate ; peristome continuous, expanded. 



Order III. — Opistho-braxciiiata. 

 Family I. — Tornattsllld^e. 

 Etallonia, Deshayes, 1864. 



Dedicated to M. Etallon, a French palaeontologist. 



Type, E. cytharella, Desh. 



Shell ovate, subfusiform, resembling certain small Mitres; 

 spire short, conical, obtuse, few-whorled ; aperture elongated, 

 narrow, base entire, subemarginate ; lip simple, acute, arched ; 

 columella thick, cylindrical, twisted in the middle to resemble 

 an obtuse plait ; acute anteriorly. 



Distribution, 3 species. Eocene. Paris basin, Yalognes. 



Act^onella. — Sub-genus, Volvulina, Stoliczka, 1865; 

 (Actseonella part, Meek, 1863). 



Type, Yolvaria lsevis, Sowerby. 



Shell ovate, volvuliform, involute, more or less attenuate 

 above, widest below the middle, entirely without any traces of 

 a spire. 



Fossil, 5 species. Cretaceous. Germany, Syria. 



Family VI. — Dorii>j2. 

 Angasiella, Crosse, 1864. 



Dedicated to Mr. G. F. Angas. 



Type, A. Edwardsi, Port Jackson. 



Animal elongated, rounded in front, attenuated and pointed 

 behind ; mantle covering the head and foot ; dorsal tentacles 

 two, clavate as in Doris ; gills plumose, less numerous, and 

 placed in front of the anus as in Triopa, and occupying the 

 median part of the back, a more forward position than in others 

 of the Doridas. 



Plocamophortjs, Euppell. 



Example, P. Ceylonicus, Kelaart sp. 

 Synonym, Peplidia, Lowe ; ? Gymnodoris, Stimpson. 

 Animal, similar to Polycera, but the tentacles are retractile 

 within sheaths. 



Distribution, 3 species. Madeira, Australia, Cevlon. 



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