176. PECTINIBRANCHIATA.—MURICIDA. 
The observations of Mr. Wilde have thrown a 
confirmatory light on the accounts handed down to 
us by ancient writers of the mode of procuring the 
dye. ‘This gentleman, when visiting the ruins of 
Tyre in 1838, found on the shore a number of 
round holes cut in the solid rock, varying in size 
from that of an ordinary metal-pot to that of a 
large boiler. In these cavities, and scattered on 
the beach around, lay large quantities of shells, 
broken, apparently, by design, but subsequently 
agglutinated together. It was evident that the 
shells had been collected in quantities, and de- 
posited in the cavities in order to be pounded in 
the very mode described by Pliny, for the purpose 
of extracting the purple dye contained in the 
animal. ‘he broken shells proved, on examination, 
to be all of one species, Murex trunculus, which 
was known to have yielded the Tyrian purple, and 
recent specimens of the same species were found. 
on the adjacent beach. 
In this family are placed the largest of univalve 
shells, such as the Trztonium, of which one species, 
richly clouded with brown and red like tortoise- 
shell, is sometimes found two feet in length; and 
the genus Cassis, well known as Helmet-shells, of 
triangular form and ponderous structure. All these 
are highly ornamented, especially the massive kinds 
from the West Indies and the Indian Ocean. The 
use of the helmets for the cutting of cameos has 
been noticed in a former page of this volume ; but 
some statistical details on the same subject may 
not be uninteresting to my readers. They were 
communicated by Mr. J. E. Gray to the Society of 
Arts, in 1847. 
Mr. Gray observed that numerous attempts have 
