42 COMPARATIVE ANATOMY AND PHYSIOLOGY. 



often spoken of as the An rag pfylr > t'n l ; the term 

 Steganophthalmata refers to the fact that their sense- 

 organs are placed in protected recesses on the margin 





A -,,^ 7 > fffi 



1'ig. 13. ^urelio aurita. 



of 



of the disc (covered-eyed medusae), and that 

 Phanerocarpa must be altered from its original signifi- 

 cance to mean only that the generative glands are 

 large and obvious. They are ordinarily free, but 

 Lucernaria is fixed; the common Aurelia (Fig. 13) is 

 a typical example of the group, while Rhizostoma is 



