84 REPRODUCTION OP LIMBS. 



of this peculiarity is, that the claw has been injured, 

 generally in single combat ; for the cray-fish are 

 terrible fighters, and the mutilated limb has been 

 cast off. Most wonderfully is this managed. 



The blood-vessels of the crustaceans are necessarily 

 so formed, that if wounded, they cannot easily heal; 

 and if there were no provision against accidents, the 

 creature might soon bleed to death. 



But when a limb, say one of the claws, is wounded 

 the limb is thrown off — not at the injured spot, but 

 at the joint immediately above. The space exposed 

 at the joints is very small in comparison with that 

 of an entire claw ; and as the amputation takes place 

 at a spot where there is a soft membrane, it speedily 

 closes. In process of time, a new limb begins to 

 sprout, and takes the place of the member that had 

 been thrown off. 



The eyes of the cray-fish are set on footstalks, so 

 as to be turned in any direction, and they can also 

 be partially drawn back, if threatened by danger. If 

 the eye is examined through a magnifying glass of 

 tolerable power, it will be seen that it is not a single 

 eye, but a compound organ, containing a great 

 number of separate eyes, arranged in a wonderful 

 order. As, however, a description of an insect's eye 

 will be given at a succeeding page, we at present 

 pass over this organ. 



At the proper season of the year, the female cray- 

 fish may be seen laden with a large mass of eggs, 



