testacellid^. 11 



Family TESTACELLID.^. 



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 tei<ta^ a shell. 



Syn. — Helicolimax, partim, Fer., 180t. Testacellus, Faure- 

 Biguet, 1801. 



Distr. — 17 sp. Europe, Canary Islands. Fossil, 2 sp. Euro- 

 pean tertiar3\ T.haliotidea, Fer. (c, 42; ci, 44). 



Animal limaciform, subcylindrical, 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 e^e-ped uncle. 



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 prej' chiefly 

 consists of earth-worms, which it hunts underground and pursues 

 through their galleries, crouching occasionall}^ 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 I'ows of stiflT bristles which encircle its 

 rings ; and by contracting its bod}^ 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 prej^, it glides 

 softly and cautiously towards it; and, apparently without taking 

 any notice of the worm, it seems to feel its wa}^, 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 



