88 INTRODUCTION TO CONCHOLOGY. 



even beyond the apex, and the marking is obliterated, 

 whilst the columella and interior of the aperture is of a 

 rich carnation-colour/^ 



M. D^Orbigny observed this species on the coasts of 

 South America, ranging from the mouth of the Eio de la 

 Plata, north of Buenos Ayres, to the Bay of San Bias, in 

 Patagonia, where it lives imbedded in the sand. Having 

 captured a specimen that was advancing from its hiding- 

 place in the w^ater, he kept it alive for several days in a 

 glass vessel, during which time the creature walked about, 

 enveloped by the lobe of its mantle. 



The genus MUra constitutes a numerous division of the 

 family Columellata, and is equally admired for the symme- 

 try and the variety of colour exhibited in its three hundred 

 and thirty species. 



Linnseus arranged the Mitres with Volutes ; but Lamarck 

 separated them, on account of important differences, of 

 which not the least obvious is their shell being long and 

 turriculated, with a marked change in the arrangement of 

 the columellar plaits, which, instead of increasing, diminish 

 in size as they descend. The animal is small, the head 

 triangular, with tentacles at the basal corners, and the eyes 

 are situated either towards the middle or the base, upon 



