- HELIX. 195 
reddish-brown within ; whorls three, wrinkled, 
with minute revolving lines. Largest breadth 
about half an inch. 
parvus, (dwarf short-tail snail,) shell horn-colour 
or blackish; whorls four, crossed by minute 
wrinkles; concave above and beneath; lip 
rounded ; mouth bluish within. Breadth less 
than the fourth of an inch. 
Section C. Tarrrtne Hevrx. Lymyxa of La- 
marck, Spire terete, or conical. 
catascopius, (conk snail,) shell thin, horn-colour- 
ed or blackish ; whorls 4 or 53 the first large 
and swelling, and the remainder decreasing ra- 
pidly to an acute apex, and are wrinkled cross- 
Wise ; aperture large, oval, not equalling three- 
fourths the length of the shell. Breadth about 
half an inch, length about three fourths of an 
inch. 
heterostrophus, shell sinistral, subovate, pale yel- 
low or brown; whorls 4, first large, the other 
tapering abruptly to an apex ; aperture large, 
somewhat oval, three-fourths equal to the length 
of the shell, pearly or blackish within, lips red- 
dish. About half an inch broad and three- 
fourths of an inch long. 
subcarinatus, sheil with three rounded subcarinate 
whorls, reticulated with striew; suture deep 5 
apex truncate; aperture oval, equal-to more 
than half the length of the shell. Length a lit- 
tle over half an inch, breadth less. 
virginica, shvil tapering to the apex, and alsoa 
little towards the base ; horn-colour, blackish 
or olive ; tinged with green under the epidermis 
