70 



POPULAR CONCHOLOGY. 



where the shells attain the largest size, a few only of the 

 species being met with in Europe ; they are chiefly litoral, 

 or found on and near the sea coast. It was from the 

 animal of this genus that the Roman purple dye was ob- 

 tained. P. patula is supposed to be the species ; it is 

 found in the Atlantic Ocean and Mediterranean Sea. The 

 species P. lapillus, found on the British coasts, affords a 

 small quantity of this colouring matter. The animals also 

 of the Scalaria and Janthina secrete this fluid, which be- 

 comes a rich purple when it has been exposed to the air. 

 This secretion is not now used, the cochineal insect fur- 

 nishing us with a dye much more readily obtained. They 

 seem to be very voracious animals, preying on other 

 molluscs. 



Concholepas. Lam. — Shell thick and rough; apex 

 inclined towards the left lip ; mouth 

 very large, with a slight notch at 

 the base ; right lip having two teeth 

 at the base ; an operculum. Animal 

 like the Purpura. — Only 1 species, 

 recent. 



Of this singular genus the onlv ^ , , 



o o J Concholepas Pcnmanus. 



species known is very abundant on 



the coasts of Peru and Chili, and is known by the name 

 of Concholepas Peruvianus. It often grows to a large 

 size, two or three inches in length, and, although not 

 beautiful, is a curious shell. In its shape it has more 

 analogy with the Patella family than any other ; but from 

 the different form of the animal, and the circumstance of 

 its constructing a large operculum, it is really not con- 

 nected with that family. The animal is eaten in South 

 America, and is so common, that at the doors of the 

 fishermen's huts there is always a large heap of these 

 shells; and they are burnt for lime. Some years ago 



