When the workmen first landed upon the Bell Rock, limpets of a very large size were common, but were soon picked up for bait. As the limpets disappeared, we endeavoured to plant a colony of muscles, 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 muscles were likely to have been useful 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 muscles 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 _Buccinum lapillus_ having greatly increased, it was ascertained that it had proved a successful enemy to the muscle. The _buccinum_ being furnished with a proboscis capable of boring, was observed to perforate a small hole in the shell, and thus to suck out the finer parts of the body of the muscle; the valves of course opened, and the remainder of the fish was washed away by the sea. The perforated hole is generally upon the thinnest part of the shell, and is perfectly circular, of a _champhered_ form, being wider towards the outward side, and so perfectly smooth and regular, as to have all the appearance of the most beautiful work of an expert artist. It became a matter extremely desirable to preserve the muscle, and it seemed practicable to extirpate the _buccinum_. But after we had picked up and destroyed many barrels of them, their extirpation was at length given up as a hopeless task. The muscles were thus abandoned as their prey: and in the course of the third year’s operations, so successful had the ravages of the _buccinum_ been, that not a single muscle of a large size was to be found upon the rock; and even the small kind which breed there, are now chiefly confined to the extreme points of the rock, where it would seem their enemy cannot so easily follow them. [Sidenote: Habits of Fishes.]