MURIC1D.E. WHELK. 133 



taceo, behind the Alcantarine Convent, at Tarento, con- 

 sisting chiefly of the shells of Murex brandaris, which 

 were supposed to have produced the purple dye; and ac- 

 cording to Dr. Bizio, the Tyrian purple was produced 

 from this Murex brandaris, and the amethystine purple 

 from Murex trunculus.% Romulus employed the purple- 

 dye for the trabea. It was purple and white, something 

 similar in cut to the toga, and was the royal robe worn 

 by the early kings. Servius mentions two other kinds 

 of trabea besides the one already described, one wholly 

 of purple, which was sacred to the gods, and another of 

 purple and saffron, which belonged to augurs. Julius 

 Csesar appears to have been the first of the Roman em- 

 perors who wore the toga entirely of purple.* 



In ' Religious Ceremonies/ p. 309, we are told that 

 the Pope celebrates Mass in Lent, Advent, and all eves 

 on which fasting is required, in a purple robe. 



Other shellfish produce purple dyes — amongst them, 

 Aplysia hybrida, and I have dyed a piece of linen with 

 the beautiful purple liquid which it emits, but it faded 

 quickly. 



Dr. Darwin mentions a large Aplysia which is com- 

 mon at the Cape de Verd Islands, five inches long, and 

 of a dirty yellowish colour, veined with purple, which, 

 when disturbed, emits a very fine purplish-red fluid which 

 stains the water for a space of a foot round. 



Scalaria communis yields a purple liquor destructible 

 by acids, and Planorbis corneus, a purplish fluid, but it 

 cannot be made of any use, though Lister tried several 

 experiments with the vain hope of being able to fix it. 

 In Spain, Murex trunculus is eaten, and Pupura lapillus 



* Pliny, Nat. Hist, see note, vol. iv. bk. xxi. chap. 22. 

 f Cic. Philipp. ii. 34. 



