THE HERMIT CRAB, (Pagurus bernhardus.)
The hinder part of its body, particularly the tail, being constantly secure from injury, has its covering reduced to almost a membranous state, while the tail, which assists the other species in swimming, is almost obliterated; but in those which have chosen a shell for their hermitage, some hook-like appendages are observed, which enable them to maintain a secure hold of their borrowed dwelling. When the body has grown too large for the shell occupied by the animal, it is obliged to seek another of a larger size. The numerous combats they enter into when seeking a new dwelling, have caused this animal to receive the additional name of the Soldier Crab.
“The [Soldier] when about to seek a new habitation, is still seen,” says an amusing writer, “in its own shell, which it appears to have considerably outgrown; for a part of the naked body is seen at the mouth of it, which the habitation is too small to hide. A shell, therefore, is to be found, large enough to cover the whole body; and yet not so large as to be unmanageable and unwieldy. To answer both these ends is no easy matter, nor the attainment of a slight inquiry. The little Soldier is seen busily parading the shore, along that line of pebbles and shells that is formed by the extremest wave; still, however, dragging its old incommodious habitation at its tail, unwilling to part with one shell, even though a troublesome appendage, till it can find another more convenient. It is seen stopping at one shell, turning it and passing it by, going on to another, contemplating that for a while, and then slipping its tail from its old habitation, to try on a new. This, also, is found to be inconvenient; and it quickly returns to its old shell again. In this manner, it frequently changes, till at last it finds one light, roomy, and commodious: to this it adheres, though the shell be sometimes so large as to hide the body of the animal, claws and all.”
Yet it is not till after many trials, and many combats also, that the Soldier is thus completely equipped; for there is often a contest between two of them for some well-looking favourite shell, for which they are rivals. They both endeavour to take possession; they strike with their claws; they bite each other, till the weakest is obliged to yield, by giving up the object of dispute. It is then that the victor takes possession, and parades in his new conquest three or four times back and forward, upon the strand, before his envious antagonist.
When this animal is taken, it sends forth a feeble cry, endeavouring to seize the enemy with its nippers; which if it fasten upon, it will sooner die than quit the grasp. The wound is very painful, and not easily cured.
On the English coasts the Hermit Crab is generally found in the shell of the whelk, or when of a small size in that of the periwinkle; they not unfrequently, however, remain in some cranny of a rock, or under the protecting cover formed by a group of pebbles, in the interstices of which they hide themselves.
The ancients were well acquainted with the [Soldier Crab], as is evident from the following translation of the lines of one of their poets:
The Soldier Crabs unarmed by nature, left Helpless, and weak, grow strong by harmless theft. Fearful they crawl, and look with panting wish For the cast crust of some new-covered fish; Or such as empty lie, and deck the shore, Whose first and rightful owners are no more. They make glad seizure of the vacant room, And count the borrowed shell their native home; Screw their soft limbs to fit the winding case, And boldly herd with the crustaceous race. But when they larger grow they fill the place, And find themselves hard-pinched in scanty space, Compelled, they quit the roof they loved before, And busy search around the pebbly shore, Till a commodious roomy seat be found, Such as the larger shell-fish living owned. Oft cruel wars contending soldiers wage, And long for the disputed shell engage; The strongest here the doubtful prize possess, Power gives the right, and all the claim confess.