268 



THE WONDER OF LIFE 



importance lies in the fact that they destroy large 

 numbers of floating fish eggs and yotmg 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 adhesive 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- 

 Fia. 4.5.— Ctenophore showing (t) retractile . r n+p^onhnTPC 



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

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

 oUiated combs ; (as) apical spot with , 



» sensory organ, (^/ter Mayer.) by equally character- 



