268 



THE WONDER OF LIFE 



importance lies Iq the fact that they destroy large 

 numbers of floating fish eggs and young fry. Dr. A. G. 



Mayer writes : — 



' Tender as they are 

 to the touch, passing 

 jelly-like between the 

 fingers of the hand 

 that attempts to seize 

 them, their food con- 

 sists largely of young 

 fishes, which they en- 

 gulf in great numbers, 

 seizing their prey by 

 means of their pecu- 

 liar adiesive cells. 

 Thus, in the cold 

 northern waters where 

 ctenophores occur in 

 vast swarms, they 

 constitute a serious 

 menace to the cod 

 fisheries by devouring 

 pelagic eggs and 

 young fish.' 



In almost all cases 

 the ordinary stinging 

 cells characteristic of 

 jelly-fishes and other 

 Coelenterates are ab- 



FlG. 45.— Ctenophore showing (t) retractfle . , fH-pnnnhoTPS 



tentacles bearing adhesive cells; (m) Sent Irom l^tenopnores, 



position of the mouth; (o) line of but their place IS taken 

 ciliated combs ; (as) apical spot with , ii i j. 



a sensory organ, (^/fer Mayer.) by equally character- 



