250 Mr. R. Warington on the Natural History 



water. Even the small eyes of an allied species, that remarkable 

 little crustacean, the Athanas nitescens, exhibit the same effect, 

 although from their shy habits and diminutive size it can be but 

 rarely observed. 



When the period arrives at which the Palcemon serratus is 

 about to throw off its old external covering, it ceases to feed, and 

 seeks about from spot to spot in a restless and fidgetty manner, 

 until it has fixed on a locality apparently sufiiciently adapted for 

 the purpose required and suited to its fancy; for this really 

 appears at times to be the case. The third, fourth and fifth 

 pairs of legs are then stretched out wide apart, and the feet 

 hooked so as to hold firmly upon the surrounding substances, 

 in such a way that the body may be poised and capable of 

 moving freely in all directions, as though suspended on gimbals. 

 The prawn then slowly sways itself to and fro, and from side to 

 side, with strong muscular efforts, apparently for the purpose of 

 loosening the whole surface of the body from the carapace ; the 

 two pair of prehensile or didactylous legs are at the same time 

 kept raised from the ground, stretched forwards, and frequently 

 passed over each other with a rubbing motion, as if to destroy 

 any remaining adhesion ; the eyes also may be observed to be 

 moved within their covering by muscular contraction from side 

 to side ; and when every precaution appears to have been per- 

 fectly taken for the withdrawal of its body from its too limited 

 habiliments, a fissure is observed to take place, betvv^een the cara- 

 pace and the abdomen at the upper and back part, and the 

 head, antennse, legs, feet and all their appendages, are slowly 

 and carefully drawn backward and out from the dorsal shield 

 until the eyes are quite clear of the body-shell or carapace, 

 and appear above the upper margin of it ; the prawn thus half 

 released then makes a sudden backward spring or jerk, and the 

 whole of the exuvium is left behind, generally adhering by the 

 shell of the six feet to the surface it had selected for its pur- 

 pose. 



A moment's consideration will develope to the contemplative 

 mind what a truly wondrous process this act of exuviation 

 really is. When we reflect on the small size of this crustacean, 

 and the extreme delicacy and intricacy of its various organs, and 

 then find that in this moulting, the shell of the most minute and 

 complicated of these structures is thrown off in a complete and 

 unruptured state, even to the gauze-like membrane covering 

 the projecting and pedicled eye, the filamentous antennse, the 

 many-jointed legs, the delicate didactylous hand, the paddled 

 abdomen with its beautiful appendages, the palpi, and all the 

 minute spines and microscopic hairs with which these various 

 members are provided, — the human mind can hardly appreciate 



