SHELLS AND MOLLUSCOUS ANIMALS. 225 



often surround the shell. This is usually about 

 an inch in length, of yellow, white, chestnut, or 

 dull orange colour: in its perfect state much 

 wrinkled, but often worn smooth. This whelk is 

 found on rocks at low water, and its fish is in- 

 teresting, because it is believed to have been one 

 which afforded that rich dye by which the ancient 

 Tyre, whose merchants were princes, was so 

 enriched. The ancients included under the 

 word which we translate purple, a variety of 

 tints, and applied it to the crimson and scarlet, 

 and much paler shades of these hues, derived from 

 shell-fish, as distinguished from vegetable dyes. 

 Pliny, from whose writings much information is to 

 be gathered on this subject, tells us that the juice 

 being extracted from the small sac in the throat 

 of the fish, was mingled with salt and boiled. The 

 flesh which adhered to it was strained off, and the 

 wool plunged into the liquid dye. Several shell- 

 fish, doubtless, contributed these purples, but 

 Pliny ranges them all into two classes, one of 

 which, he says, was found on cliffs and rocks, and 

 yielded a dull blue dye which he compares to the 

 tint of the raging sea; the other, the Purpura, 

 the proper purple shell, taken by fishing in the sea, 

 yielded the rich crimson hue, which he likens to that 

 of rich red roses, or to coagulated blood. This was 

 the valued ancient purple colour. There is no doubt 

 that the ancient Tyrians used a species of rock-shell 

 common all along the shores of the Mediterranean, 

 the Murex trunculus, in their dye, as Wilde found 

 a concrete mass of the shells in some of the ancient 

 dye-pots, sunk in the rocks of Tyre. The dye 

 was very costly, owing to the small quantity which 

 could be procured from each fish, and to the many 



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