GASTEROPODA. 
Sub-geuus :—Taheitia, H. and A. Adams, 1863. 
Type, Truncatella porrecta, Gould, Taheiti. Operculum 
shelly, furnished with erect radiating lamellze. Aperture of shell 
ovate ; last whorl separate; peristome continuous, expanded. 
ORDER IJII.—OPISTHO-BRANCHIATA. ~ 
Faminty I.—ToRNATELLIDA. 
ETALLONIA, Deshayes, 1864. 
Dedicated to M. Etallon, a French paleontologist. 
Type, K..cytharella, Desh. 
Sheil 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. Hocene. Paris basin, Valognes. 
ACTZONELLA.—Sub-genus, Volvulina, Stoliczka, 1865; 
(Acteeonella part, Meek, 1863). 
Type, Volvaria levis, 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. 
Faminty VI.—Dorinz&. 
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 Doride. 
PLOCAMOPHORUS, Ruppell. 
Example, P. Ceylonicus, Kelaart sp. 
Synonym, Peplidia, Lowe; ? Gymnodoris, Stimpson. 
Animal, similar to Polycera, but the tentacles are retractile 
within sheaths. 
Distrioution, 3 species. Madeira, Australia, Ceylon. 
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