CRABS AND SHRIMPS. 



219 



colourless that they can scarcely be detected but for the 

 eyes, which are of a lovely blue hue, and are carried at 

 the end of long stalks. 



Our common Prawns (Palcemon) are beautiful examples 

 of pellucid structure ; and when alive, they form, from 

 this circumstance, from the dark-brown lines with which 

 they are adorned, from their elegant shape, and sprightly, 

 graceful motions, very interesting objects in a marine 

 Aquarium ; the more so as they are among the most easily 

 kept, being readily reconciled to captivity, and keeping 

 themselves in health and condition, without trouble to their 

 possessor, on the animalcules and garbage that else would 

 accumulate on the bottom. Their manner of feeding, by 

 the hand-like use of their long slender claws, which seize 

 the food and present it to the mouth ; the brushes of hair 

 with which some of the feet are fringed, serving as cleansing 

 organs, and the effective way in which these are made to 

 reach all parts of the body, and to keep it scrupulously 

 clean ; the flapping of the false feet beneath the abdomen 

 in the process of ordinary swimming; the occasional sud- 

 den stroke upon the water of the broad tail-plates when 

 the creature is alarmed, causing it to shoot backward with 

 the rapidity of thought to the distance of several inches ; 

 the structure of the eyes, and the singular reflection of a 

 candle from their interior, like the flash of a policeman's 

 buWs-eye; and even the internal organs, the pulsation of 

 the heart, and the passing of the food, as masticated, 

 into the stomach, can all be seen and studied to advan- 

 tage in these parlour pets. An hour's observation on 

 their organisation and their manners, if our readers have 

 ihe opportunity of watching any marine Aquarium, 



