4700 Crustacea. 



the wonderful wisdom of the Creative power that could have called 

 into existence so marvellous an adaptation. 



At the moment the prawn has been thus liberated from its old en- 

 velope, it rolls on the surface of the ground perfectly helpless, for it is 

 at first, evidently, so soft that it does not possess the power of sup- 

 porting its own weight erect upon its feet, while the beautifully delicate 

 antennae float from its head like gossamer threads through the water. 

 In a short time, however, it plunges or springs, by a strong muscular 

 exertion of the abdomen, from place to place, stretches its webbed 

 tail and the large paddles of its swimming apparatus, and soon retreats 

 into some dark and sheltered corner, where it remains, continually 

 exercising its various organs, until such a period as the new investing 

 membrane shall have become sufficiently hardened to allow of its ven- 

 turing forth among its companions without danger, for during all this 

 interval it is liable to their attacks whenever it comes near them, and 

 is obliged by a series of forcible leaps rapidly to evade their attempts 

 and escape out of their way. When the newly coated Palaemon first 

 makes its exit from its hiding-place, its appearance is doubly beauti- 

 ful ; the colours are so clear and bright, particularly the orange and 

 rich brown bands which encircle the pale blue prehensile feet, the 

 various markings are so defined, and the small spines and fringes of 

 hair so clean and well developed, and the deportment of the creature 

 itself is altogether so bold and vain-glorious, as though proud of its 

 new vesture, that it cannot but command the admiration it seems to 

 seek. 



It may be interesting to specify here the intervals of this moulting 

 as they were observed during the summer of 1853. These periods 

 were ascertained in the following manner. When the observations 

 first commenced there were eight healthy prawns in the aquarium, and 

 as each exuvium was cast off it was removed from the water and the 

 date noted down, and by continuing this process the following results 

 were obtained : — 



May 25th, two cast skins were removed. 



„ 29th, two 



„ 31st, one cast skin was removed. 

 June 5th, one „ „ 



„ 7th, two cast skins were removed. 



„ 9th, two „ „ 



„ 12th, two „ ,, 



„ 14th, two „ „ 



„ 16th, one cast skin was removed. 



