This mutilation is so common in some localities, that Professor Steenstrup says[70] that almost every octopus he has examined has had one or two arms reproduced; and that he has seen females in which all the eight arms had been lost, but were more or less restored. He also mentions a male in which this was the case as to seven of its arms. He adds that whilst the _Octopoda_ possess the power of reproducing with great facility and rapidity their arms, which are exposed to so many enemies, the _Decapoda_--the _Sepiidæ_ and Squids--appear to be incapable of thus repairing and replacing accidental injuries. This is entirely in accord with my own observations.
[70] Ann. and Mag. Nat. Hist. August, 1857.
This reparative power is possessed by some other animals, of which the starfishes and crustacea are the most familiar instances. In the case of the lobster or crab, however, the only joint from which new growth can start is that connected with the body, so that if a limb be injured in any part, the whole of it must be got rid of, and the animal has, therefore, the power of casting it off at will. The octopus, on the contrary, is incapable of voluntary dismemberment, but reproduces the lost portion of an injured arm, as an out-growth from the old stump.
The ancients were well acquainted with this reparative faculty of the octopus: but of course the simple fact was insufficient for an imaginative people: and they therefore embellished it with some fancies of their own. There lingers still amongst the fishermen of the Mediterranean a very old belief that the octopus when pushed by hunger will gnaw and devour portions of its arms. Aristotle knew of this belief, and positively contradicted it; but a fallacy once planted is hard to eradicate. You may cut it down, and apparently destroy it, root and branch, but its seeds are scattered abroad, and spring up elsewhere, and in unexpected places. Accordingly, we find Oppian, more than five centuries later, disseminating the same old notion, and comparing this habit of the animal with that of the bear obtaining nutriment from his paws by sucking them during his hybernation.
"When wintry skies o'er the black ocean frown, And clouds hang low with ripen'd storms o'ergrown, Close in the shelter of some vaulted cave The soft-skinn'd prekes[71] their porous bodies save. But forc'd by want, while rougher seas they dread, On their own feet, necessitous, are fed. But when returning spring serenes the skies, Nature the growing parts anew supplies. Again on breezy sands the roamers creep, Twine to the rocks, or paddle in the deep. Doubtless the God whose will commands the seas, Whom liquid worlds and wat'ry natives please, Has taught the fish by tedious wants opprest Life to preserve and be himself the feast."