298 FUNCTIONS AND INSTINCTS. 



Tyrian purple is no longer in request. I could 

 say much, observes the author just named, upon 

 the finding, fishing, and method of dying of the 

 purpura, about the price formerly enormous, 

 nearly equalling that of pearls, a single shell, 

 according to Aristotle, selling for a mina or about 

 31. concerning the time at which it began gra- 

 dually to grow out of fashion, and at length to be 

 wholly neglected : so that now it is never used, 

 and no one knows the method of preparing it. 

 In fact, the cochineal seems to have supplanted 

 it, but it would surely be an object of great 

 interest to re-discover the Tyrian rock-shell, as 

 well as that which yielded the azure colour, and 

 ascertain how far they deserved, especially the 

 former, the high encomiums bestowed upon them, 

 and to deck imperial shoulders. The shells are 

 probably still in existence on the coast of Pales- 

 tine. It was the custom to crush the shell as 

 soon as taken, for if kept the animal was wont 

 to vomit its flower, as the purple die was called 

 by Aristotle. This great philosopher thought 

 the purpura lived six years, as the adult animal 

 had six whirls in its shell, and he supposed one 

 to be formed annually. He gives a detailed 

 history of these animals, of their congregating 

 in the spring, and of their forming a kind of 

 comb, like bees ; he also mentions several kinds 

 of them, that the small shells were bruised, 

 and the animal extracted from the large ones ; 



