THE AMERICAN LOBSTER. 103 



joints of the claws, to prevent them from injuring- each other, lias been generally 

 abandoned. Mutilated lobsters are now often placed in pounds, where they are 

 allowed to repair their injuries. 



One has only to examine a lot of freshly captured lobsters to be assured of how 

 common the practice of casting the claw is. "Out of a hundred specimens," says 

 Rathbuu {155), "collected for natural-history purposes in Narragansett Bay in 1880, 

 fully 25 per cent had lost a claw each, and a few both claws." In a total of 725 lobsters 

 captured at Woods Hole in December and January, 1893-94, 54 or 7 per cent had 

 thrown off one or botli claws. 



It is often stated that lobsters sometimes cast their claws during thunder storms, 

 but until some proof of the truth of this statement is afforded it must be regarded as 

 a fable. One of the earliest versions of this idea which I have seen is that of Travis 

 (191), who wrote to Pennant in 1777 that — 



Lobsters fear thunder, and are apt to cast their claws on a great clap. I am told they will do 

 the same on firing a great gun, and that when men-of-war meet a lobster boat a jocular threat is 

 used, that if the master does not sell them good lobsters they will salute him. 



Since autotomy is the result of a reflex nervous impulse, and has been acquired 

 by the animal as a meaus of defense, we should expect to And that the reflex center 

 would always be aroused into activity by stimuli coming through the nerves of the 

 limb, as is always the case in experiment, and not through a higher center like the 

 brain. When an animal is frightened by loud noises it is impelled to flee, and it would 

 manifestly be of no advantage to the animal to immediately drop its legs. 



REGENERATION OF APPENDAGES. 



The regeneration of lost limbs in Crustacea has been studied by Reaumur (161) 

 Goodsir (80), Ohantran (38, 40), and Brook (26). 



Reaumur's general account of the process in the crayfish is one of the best which 

 has been written. He quotes JDu Tertre (55), who had " made similar observations 

 on the crabs of Guadeloupe, of which he has giveu a very curious history." Reaumur 

 began his experiments on the seacoast, but the sea broke and carried away his boxes 

 or filled them with sand. He then experimented with crayfishes with more success. 

 He says : 



I took several of them, from which I broke off a leg; placed them in one of the covered boats 

 which the fishermen call " Boutiques," in which they keep fish alive. As I did not allow them any 

 food, I had reason to suppose that a reproduction would occur in them like that which I had attempted 

 to prove. My expectation was not in vaiu. At the end of some months I saw, and this without 

 surprise, since I had expected it — I saw, I say, new legs, which took the place of the old ones, which I 

 had removed; except in size they were exactly like them; they had the same form in all their parts, 

 the same joints, the same movements. A kind of regeneration like this hardly less excites our envy 

 than our imagination; if, in the place of a lost leg or arm, another would grow out again, one would 

 he more willing to adopt the profession of the soldier. 



He noticed that the time necessary for the production of new legs was indetermi- 

 nate, depending upon a variety of conditions: 



These limbs arise and grow more or less rapidly, like plants, according as the season is more or 

 less favorable; the warmer days are those which hasten the more their formation and growth. 



Sometimes new legs sprout out in three weeks; sometimes not until after six, and 

 when the legs are broken off in winter they do not grow again until summer. 



