46 TESTACEA. 



This creature feeds readily on mussel, then protruding a real pro- 

 boscis, which is short ; nor is other animal matter rejected 



It is active and vivacious, twisting itself in such a manner as 

 threatens to tear the body from the shell ; meanwhile the long snout is 

 far extended. 



Specimens have survived fifteen months or more in confinement. 



Some of the vermicular tribes prey on the mussel. 



MUREX ATTENUATUS. — Plate X. Figs. 5, 0, 7. 



Length of the shell four or five lines ; volutions six, ribbed longitu- 

 (^inally. Animal a limax ; a black eye at the external root of each ten- 

 tacuilum ; snout proportionally shorter than that of the preceding species ; 

 posterior extremity obtuse ; colour of the whole light brown ; marine. 



Plate X. 



KiG. .5 Murex attejiuatus. upper surface. 



6. Under surface of the animal. 



7. Interior of the same, enlarged 



F L .A T T E N E D SPIRAL TESTACEA 



Among the more singular arrangements to be instanced of the dis- 

 posal of nature, combining organic with inanimate matter, is lodging a 

 living being in a cavity iashioned as a logarithmic curve, for its perma- 

 nent abode. 



The body of some of these creatures seems so disproportioned to 

 their testaceous dwelling, according to our habit of viewing relative 

 dimensions — the gait of the animal so unsteady, from its slight hold of 

 the surface it traverses — independently of the respective position of both 

 the tenant and its habitation being so much at variance with convenience 



