CHAPTEE III 



COELENTERATA {continued) 



Class ir. : SOYPHOZOA (Jelly-fishes) 



Type : The Common Jelly-fish {Aurelia aurita). 



The ordinary large Jelly-fishes are very like the medusae of 

 the Hydrozoa, but they develop differently and have a 

 somewhat different structure. 



The commonest form round our coasts is Aurelia aurita. 



Fig. 16. — The Common Blue Jelly-fish (Aurelia aurita). 



Seen from the side, with the mouth-lobes hanging down below, and the horse-shoe 



shaped reproductive organs showing through the transparent upper surface. 



These jelly-fishes are often washed up in large numbers on 

 flat beaches, and vary in size from two inches to a foot or 

 more in diameter. 



Aurelia has an inverted bowl -shaped body with eight 

 notches round the margin of the bowl, and a fringe of small 

 marginal tentacles (Fig. 16) ; also at each notch is a pair 



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