PHYLUM CCELENTERATA 

 st s t 



Fig. 52. — Aurelia aurita, development A, planula: B, C, formation of the eullet 

 or stomndaeum; D, transverse section of young scyphula; E, scyphula; F, 

 longitudinal section of same; G» division of scyphula into ephyrulse; H, ephy- 

 rula from the «ide; T, the same from beneath. In A D and F the ectoderm 

 is unshaded, the endoderm striated, and the mesoglcea dotted, a, lobes of 

 umbrelli; mnb, manubrium; wM, mouth; j-y, septal funnel; st, stomodaeum ; 

 t, tentacle; t>i, taenioles, or gastric ridges. (From Korschelt and Heider's 

 Embryology ) 



