304 TURBINID A. 
Famity TURBINID 4. 
Shell spiral, turbinated, nacreous inside. Operculum calca- 
reous, paucispiral. 
Animal. Tongue elongate, median teeth broad, laterals five, 
denticulated, uncini very numerous, slender, with hooked points 
(xii, 47). Head proboscidiform ; tentacles subulate, sometimes 
ciliated; eyes on free peduncles at their outer bases; two 
more or less developed head-lobes between the tentacles. Gill 
single, long and linear. Sides of the foot with a large neck- 
lappet near the eye-peduncle, continuous with a conspicuous 
side-membrane, bearing on its free margin from three to five 
tapering filaments; operculigerous lobe often ornamented with 
cirri. Littoral and herbivorous, characterized by the fringed 
lobes and tentacular cirri of the head and sides, their peduncu- 
lated eyes, and by the pearly nature of their shells beneath the 
epidermis and outer layer. They are invariably marine, feeding 
on the sea-weeds which abound along the shore, and are distrib- 
uted in all parts of the globe, being most numerous and of larger 
growth and more beautiful colors in tropical seas. 
The Turbinide are distinguished from the Trochidez, generally 
by the form of the shell, and by the operculum, which is calca- 
reous and paucispiral in the former, corneous and multispiral 
in the latter. The arrangementsof the groups of both families 
corresponds with that proposed. by Dr. Paul Fischer. in_ his 
excellent monographies of Trochus and Turbo. 
Turso, Linn. 
Top-shell. Htym.— Turbo, a whipping top. 
Distr.—T6 recent sp. World-wide in tropical seas. Fossil, 
400 sp. L. Silurian—; universally distributed. 7. marmor- 
atus, Linn. (1xxix, 10). 
Shell turbinated, solid; whorls convex, smooth or often 
grooved or tuberculated ; aperture large, rounded, slightly pro- 
duced in front. Operculum shelly and solid, callous outside, and 
smooth, or variously grooved and mammillated, internally horny 
and paucispiral. In 7. sarmaticus the exterior of the operculum 
is botryoidal, like some of the tufaceous deposits of petrifying 
wells. : 
TURBO (restricted). Shell smooth, or tuberculate, covered by 
a smooth epidermis; inner lip flattened, more or less produced 
in front; no umbilicus. Operculum spiral on its inner face, 
convex and smooth or granular (not ridged) externally. 17 sp. 
Indian and Pacific Oceans, W. Indies. 
The “green snail” of the dealers, the Turbo marmoratus, is 
very largely used for ornamental purposes. Slices of this shell 
ground down toa thin surface, are employed for covering or 
inlaying various articles,such as small stamp-cases, fancy boxes, 
