50 MOLLUSCA. 
and the inhabitants of Sicily weave them into a 
sort of cloth remarkable for its softness and warmth, 
but which refuses to take any dye. In the British 
Museum, together with some very fine specimens 
of the shells of this Mollusk, there is a pair of 
gloves made of its byssus; but articles made of this 
material are very costly, and cannot be considered 
in any other light fhan that of curiosities. Pope 
Benedict XV, in 1754, had a pair of stockings 
presented to him which were woven from the silk 
of the Pinna. These were the subject of general 
admiration, from the extreme delicacy of their 
texture—well shown by the minuteness of the box 
in which they were enclosed. 
The mention of the ship-worm naturally presents 
to the mind another tribe of bormg Mollusca,— 
those which perforate hardened clay, and even stone. 
These, belonging to various genera, are sufficiently 
common on our own coasts. Different species of 
Pholas excavate their burrows, which resemble the 
holes bored by augers or large gimlets in wood, 
clay, and sandstone; the Venerwpis in shale and 
similar friable rocks, the Lithodomi and Saxitcave 
in the limestone, and the Gastrochena in limestone, 
fluor, and granite. A curious example of the boring 
powers of one of these species, the Modiola:litho- 
phaga, occurs at Pozzuolo, in the Bay of Naples, 
where a colony of these Mollusks had settled 
themselves in the pillars of the temple of Jupiter 
Serapis during the period of its submersion. At 
the height of ten feet above the base of the three 
standing pillars which remain, and in a position 
exactly corresponding in all, is a zone of six feet 
in height, where the marble has been scooped into 
cells by these Mollusca. The holes are to the 
