246 ASTACID.E. 



by this means. If time were given new claws would be 

 formed. It is a voluntary act, and does not injuriously 

 affect the animal." The following remarks on this sub- 

 ject, by my observant and accurate friend Mr. Couch, 

 will be read with much interest, and I need offer no 

 apology for their extent. 



Mr. Couch first speaks of the effects of injuries to the 

 antennae, and observes that it is an erroneous opinion 

 that these organs are ordinarily thrown off in consequence 

 of violence done to them, and afterwards renewed. " I 

 have not," he proceeds, " found this to be the fact ; but, 

 subjecting the parts to blows or fracture, both in short 

 and long-tailed Crustaceans, I have found the creature 

 suffering acutely from the injury, most so when just 

 emerged from the water ; but in no case have they rcT 

 jected the whole organ in consequence of the violence. 

 If, however, it be violently handled, a separation takes 

 place at the terminal joint of the peduncles, in preference 

 to any other place ; and from this wound no stream of 

 blood flows, but a fine membrane quickly forms on the 

 surface, by which all effusion is prevented. This pre- 

 servative process resembles that which takes place in 

 case of the loss of the legs, and for the same purpose ; 

 for crabs and lobsters soon bleed to death, if the hsemor- 

 rhage be not restrained. It is only the legs, including 

 those bearing the chela or nippers, that are readily and 

 willingly thrown off by the animal ; and in some cases, 

 as in Porcellana plat^cheUs, this is not only done on the 

 infliction of violence, but as if to occupy the attention of 

 some dreaded object, while the timid creature escapes to a 

 place of safety. The general method of defence is to seize 

 the object with the pincers, and while these are left attached, 

 inflicting, by their spasmodic twitchings, all the pain they 



