these sti-ucUires but refuses to regard bhem in the same way 

 that Goette does. Goette says (p. 26) that the scyphi stoma 

 maintains the typical st-ructure of an anthozoan usually until 

 the eight tentacle stage. It seems to me tiiaL tiiis stage is 

 much more ti^ansitory. The septal m.uscles arise in Aurelia 

 according to (^oette in the four tentacle stage and it is with 

 the appearance of these very distinctively medusoid sti-uctures 

 that I should say the larva loses its supposed anthozoan char- 

 acter. The septal muscles are peculiar to the scyphomedusae, they 

 are found in no other group of animals and every scyphomedusa 

 possesses them at some stage of its existence. In the buds of 

 Cassiopea these are produced very early, while the bud is mere- 

 ly a hemispherical evagination on t.he side of the scv-phistoma, 

 and the bud could not, therefore, ever pass through an antho- 

 zoan stage. 



The early development of these muscles is further evidence 

 for the supposition thai this planula-like bud is a modifica- 

 tion of a phylogenetically earlier condition with mouth and 

 Lentacles, perhaps as in Aurelia. 



It is to be expected that the organs of a non-sexually 

 produced animal will be derived from the same germ layers that 

 give rise to corresponding organs of a related animal that has 



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