TESTACELLID. elt 
Famity TESTACELLID A. 
Animal slug-like, bearing a small ear-shaped shell near the 
posterior extremity of the body. No jaw. Lingual teeth long 
and narrow, sharp-pointed, in oblique series. 
TESTACELLA, Cuvier, 1800. 
Etym.—Diminutive of testa, a shell. 
Syn.—Helicolimax, partim, Fer., 1807. Testacellus, Faure- 
Biguet, 1801. 
Distr.—17 sp. Europe, Canary Islands. Fossil, 2 sp. Euro- 
pean tertiary, 7. haliotidea, Fer. (c, 42; ci, 44). 
Animal limaciform, subeylindrical, tapering anteriorly ; ten- 
tacles simple; mantle small, posterior, quite near the tail, covered 
with a small external shell; no longitudinal furrows above the 
margin of the foot, and no caudal mucous pore; no distinct loco- 
motive disk; external respiratory and anal orifice at the posterior 
right edge of the mantle under the peristome of the shell; com- 
bined generative orifice behind and below the right eye-peduncle. 
Shell external, rudimentary, imperforate, ear-shaped, with a 
subspiral, posterior nucleus. 
“The Testacella is one of the few land-mollusks with true 
predaceous habits; its marine representatives in this respect 
being the cuttle and the whelk. It is scarcely inferior to the 
tiger, snake or shark in its cunning and ferocity. Its prey chiefly 
consists of earth-worms, which it hunts underground and pursues 
through their galleries, crouching occasionally and making a 
spring on its victim. It is said that when the poor worm has 
had the start-of its pursuer, the snail-slug intercepts it by tun- 
neling across the line of its "retreat. It will devour a lob-worm 
much longer than itself, seizing it in the middle; and when the 
writhings have been succeeded by exhaustion, it detaches and 
swallows one-half of the worm; and after that has been digested 
it finishes its long meal with the other portion, For this purpose 
its mouth is furnished with an apparatus of sharp recurved teeth, 
which enables the Testacella to retain a firm hold of its victim 
and swallow it more easily. The worm is provided with some 
means of defense, in the rows of stiff bristles which encircle its 
rings; and by contracting its body a short respite is occasion- 
ally gained. But the chance of ultimate escape or safety is very 
slight. When the Testacella sees or scents its prey, it glides 
softly and cautiously towards it; and,apparently without taking 
any notice of the worm, it seems to feel its way, and usually 
succeeds in fastening itself on an unprotected part of the body 
between the rings. The attack, if unsuccessful at first, is renewed ; 
but if the worm resists too long, the Testacella gets impatient, 
and by pressing or doubling its victim into the earth, by which 
