1 COMMON HERMIT-CRAB (Pagurus bernhardus) in shell of common Whelk
2 COMMON HERMIT-CRAB out of shell
3 SHIP BARNACLES
V.
Twice in every twenty-four hours the waters of the ocean ebb and flow. Twice only in each month, however, do the spring-tides occur. For there are few dangers that the ardent student of nature would not encounter. Lord Bacon tells of a certain bishop who used to bathe regularly twice every day, and on being asked why he bathed thus often, answered, 'Because I cannot conveniently bathe three times.' The zoologist, like the 'right reverend father' alluded to, would willingly undergo what appears to others much hardship and trouble, not only once or twice, but even three times daily, in pursuit of his favourite studies, did Nature but offer the kind convenience.
On these occasions the zoologist can pursue his researches at the shore, at a distance beyond the usual tidal line. Numerous boulders and rock-pools, during many days covered by the sea, being then laid bare and exposed to his eager, searching hands and eyes, he is frequently able to discover many rare objects, or, at least, common ones revelling in almost giant-like proportions, and wonderful profusion.
The Soldier or Hermit-Crabs (to an account of whom we intend to devote this chapter), offer a most remarkable proof of this. Occupying the centre of a rocky excavation, I have repeatedly found several dozen of these comical creatures, each inhabiting the cast-off shell of a defunct Whelk (Buccinum undatum), which measured not less than five or six inches in length. To my surprise these aldermanic crustaceans possessed no companions of a smaller growth; while at a few yards nearer shore, as many shells would be found congregated together as in the more distant pool,—the largest, however, being no bigger than a damson, while the smallest might be compared to an infantile pea, or cherry-stone.
I cannot explain this appearance otherwise, than by supposing that the Anomoura become prouder, or, it may be, more cunning, as they grow older, and, having arrived at their full development, they fit themselves with their final suit; thereafter, in a spirit of aristocratic exclusiveness, they retire to fashionable subaqueous residences, distant as far as possible from the homes of the canaille, who inhabit the common, littoral boundaries of the shore.