192 UNIVALVES —— DENTALIUM. 
cidum is very narrow and thin, and is of a pale topaz 
color; it is remarkable that this shell does not effer- 
vesce in acids. 
The Dentalia are principally found in the Indian and 
European oceans; and a few in the Mediterranean and 
Northern seas, 
The term Dentalium has been applied to this genus, 
from the marked resemblance which its species bear to 
a tooth (Dens). 
Faminy 1.—With longitudinal ribs. 
Scientific Name. Locality. Common Nume. 
Rectum -------:- Indian Seas ---++++++++- Straight Tooth S. 
Elephantinum --- Indian & European Seas, 
Mauritius --+++- +++ Elephant’s- do -- 
Aprinum ---++--- Indian Seas -----++++++- White ribbed do 
Striatum ----+--- Sicily, Cornwall-------- Striated -- do -- 
Dentalis ---+---> Mediterranean, Amboyna, 
West of England ---- Curved striated do 
Fasciatum -+-..e. Sicily alisvel sfeVareialsieistataiel stele Banded --- do -- 
Imperforatum --- Sandwich, Falmouth --. Minute-truncated 
FamiLy 2.--With annular striae. 
Politum -.------ India, Sicily --------.-- Ring-striated do - 
Eburneum ------ India-+-++-++++++seeeeeee Smooth-ivory do - 
Trachea ---+---- Milton in Devonshire -- Minute Windpipe 
Famity 5.—Smooth. 
Entalis ---++--- - Britain, India, Norway -- Common -- do -- 
Corneum ------- African Ocean --+-+-+++- Horn-color’d do - - 
Gadus ---+-++-++-- British Channel ---+---- Hake’s ---- do -- 
Minutum ------- Mediterranean, Devon -- Minute---- do -- 
Pellucidum ----- North Sea -+-+-- cece - Pellucid --- do-- 
