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SHELLS AND MOLLUSCOUS ANIMALS. 



Another frequent shell of our coast, is the 

 common False wentletrap (Scalar ia communis), 

 which is generally of a whitish colour. ^ Its form 

 is sufficiently described by our engraving; the 



ribs are somewhat thick and smooth, and they are 

 sometimes marked with purple spots, while the 

 whole shell has occasionally a pinkish purple 

 tinge. More than eighty species of wentletrap 

 are described by naturalists. The Royal Stair- 

 case wentletrap (Scalar ia pretiosa) was once a 

 rare object among collectors, and a fine specimen 

 is known to have been sold in France for a 

 hundred louis, and in England for twenty or thirty 



