SHELLS AND MOLLUSCOUS ANIMALS. 223 



alike, the Louse-pig cowry, or Nun cowry (Trivia 



pediculis), represented by our engraving, being very 



general. It is of a pale reddish colour, 



with six square black spots on the 



back. The flesh-coloured Pig cowry 



is thinner and clearer, of a beautiful 



rose tint; and the European Pig 



cowry has ribbed ash-coloured or pinkish shells, 



marked down the back with a white streak and 



three black dots. 



The cowries live at the base of the sea or along 

 the shore in sands, and their beautifully polished 

 surfaces are preserved free from any extraneous 

 matters, by means of a membrane with which the 

 animals are provided, and which they throw over 

 the shells. They are found in greater number in 

 the Tropical than in European seas ; and in climes 

 in which all the colours of nature deepen into 

 richer and more glowing hue, they are far more 

 highly tinted. The foreign species have been 

 prized from time immemorial for their beauty, and 

 the little Money cowry (Cypraea moneta) is used 

 for current coin in many parts of India, in Siam, 

 and on the coast of Guinea. Though inferior in 

 value to gold or silver, yet so long as the shell is 

 unbroken it will pass for money, and accounts are 

 kept in cowries in some departments of business. 

 The cowry is obtained from the Philippine Isles, 

 and it is very common in this country. It is called 

 the trussed chicken, which object it much resembles 

 in shape. The shell is yellow or white, with a 

 yellow ring. 



Among the commonest of our marine mollus- 

 cous animals is the waved whelk (Buccinum 

 undatum). Its large firm shell frequently lies in 



