230 MOLLUSCA- 
noxious fry of the star-fish; and likewise to a disease to 
which the animal is subject in spring, under the influence 
of which it melts away, and falls from the rocks. Besides 
being useful to man as an article of subsistence, the mussel 
supplies the fisherman with one ofhis most convenient andsuc- 
cessful baits. It is keenly taken both by cod and haddock. 
To the cod-fish, however, the animal of the horse-musse! 
(Modiola vulgaris) is more acceptable. 
The following unsuccessful attempt to plant a colony of 
mussels is recorded by Mr. Stevenson in his interesting 
work, (p. 73,) in which he gives the details of the erection 
of the light-house on the Bell-Rock: “ When the work- 
men first landed upon the Bell-Rock, limpets ofa very large 
size were common, but were soon picked up for bait. As 
the limpets disappeared we endeavoured to plant a colony 
of mussels, from beds at the mouth of the river Eden, of a 
larger kind than those which seem to be natural to the 
rock, These larger mussels were likely to have been use- 
ful to the workmen, and might have been especially so to 
the light-keepers, the future inhabitants of the rock, to 
whom that delicate fish would have afforded a fresh meal, 
as well as a better bait than the limpet; but the mussels 
were soon observed to open and die in great numbers. For 
some time this was ascribed to the effects of the violent 
surge of the sea, but the Buccinwm lapillus, (Purpura,) 
having greatly increased, it was ascertained that it had 
proved a successful enemy to the mussel. The buecznum, 
being furnished with a proboscis capable of boring, was ob- 
served to perforate a small hole in the shell, and thus to 
suck out the finer parts of the body of the mussel; the 
valves of course opened and the remainder of the fish was 
washed away by the sea. The perforated hole is generally 
