Ccelenterates 49 



powers are such that they are more 

 dreaded than the shark by the sponge 

 and coral fishermen. Juvenile " Men-of- 

 War " can sink at will by expelling gas 

 from the float, but lose this power on 

 attaining maturity. Their chief enemy 

 is the turtle, who devours them greedily 

 always closing its eyes, however, when 

 attacking. 



Certain giant species of jelly-fish are 

 popular as shelters for young fishes and 

 crustaceans, who thereby not only enjoy 

 considerable immunity from foes, but 

 obtain a quantity of animals, small crea- 

 tures paralysed by the stinging cells of 

 the jelly-fish. 



At night these and allied creatures 

 may give the most remarkable displays 

 of phosphorescence. Mr. A. C. Hardy, 

 a member of the recent Discovery ex- 

 pedition to the Antarctic, has given a 

 vivid description of phosphorescent Cten- 

 ophora, which give out brilliant and 



D 



