PHYLUM COELENTERATA 



139 



Lonq tentacles -- 

 (in Chryiaoro) 



Larqe subqenibal pit (as in Chrysaora) 



TentaculocyJt 



Admdial canal 



Perradial canal 



Jhort5f'mp/e oral 

 - arm (Aurelia) 



■ -^^ >-:, -Intenadial canal 



■ ;■ . • ■ • . .'iv. - •*. -iy ■ :T*L^5=f'^^^"""V C Admdial canal 



■i^-:- ■:■■■ lIfJ&;^-#- vV-i^^:?-----^'"'?^"^' 



'S^_]_; V^ _ _ Aon(7 ribboh-like oral 

 ' ^ ) j "^ arm (in Chrysaom) 

 - 'Small 6iibgenibal 

 /^C"""^ p/fc (aj /n Aurelia) 



^ '^ Qastric pouch 



'^ Short tentacles 

 (Aurelia) 



Fig. 63. 



Marqinal lobes (as in Chrysaora) 



-Aurellia and comparative structure of jellyflshes. (Modified from figure 

 in Pacific Biological Laboratories' catalogue.) 



Stages in the 

 development 

 of the scyphis 

 toma 



Planula MM 

 larva ^^ 



Stages in the 

 -development 

 ^of the jbrobila 



Zygote 



Sperm from 

 separate adult 



Fig. 64. — Life cycle of Aurellia aurita, showing staj^es from germ cells to the 

 ephyra stage which precedes the adult condition. 



