30 THE SIIELL-FISH OF THE COAST. 



nion species of the Southern shore, wentletrap 

 {Scalaria, PI. 1, Figs. 12, 13), and purple {Purpura 

 lapiUits, PI. 1, Figs. 9, 10). By pressing on the oper- 

 culum of the last-named a fluid is released of a dull 

 crimson color, much resembling some of the purples 

 of antiquity ; indeed, it was from one of the species 

 of this genus that the ancients obtained some of 

 their more highly prized dyes. The purple is a 

 rough customer among the oyster- and muscle-beds, 

 where its depredations extend as well to the dead 

 as to the live animal. It is not, however, satisfied 

 with these delicacies alone, but will also venture on 

 limpets, barnacles, dead fish, etc. If by habit a 

 pirate, the purple in turn sufliers from the piracy of 

 other animals, and largely so from the seemingly 

 harmless hermit-crabs. These have on more than 

 one occasion been observed to sally forth under 

 protection of their borrowed castles, and clean out, 

 so to say, the purple, dragging their unfortunate 

 victim from the shell. In one such encounter, as 

 narrated by Mr. Crowther, of Whitby, England, 

 the attacking party were shielded by the shells of 

 four distinct species of snails — a dog-whelk, peri- 

 winkle, troque, and purple. 



Partaking largely of the habits of the purple is 

 the ' drill' (Urosalpinx cinerea, PI. 1, Fig. 8), a name 

 suggestive of the methods employed bj'^ this animal 

 to obtain its food. Like the last-named, it is a great 

 destroyer of the oyster. 



Our description of this section of the shore-fauna 

 would not be complete without a special reference 

 to the sandal or slipper-limpet (Crepidida) and the 



