be at a great distance from the parental, sexually produced 

 scyphistoma. 



The resemblance of the swimming bud of Cassiopea to the 

 planula of Aurelia is extraordinary. Both are ciliated and 

 have the same movements, the shape is the same, both being a 

 slightly flattened oval with the more acute end posterior and 

 it is at ihe posterior end in both that the mouth arises. It 

 is only when these larvae are examined in sections ti^iat the 

 difference appears. The bud has, in distinction from the pla- 

 nula, a thick supporting or gelatinous layer, and the four sep- 

 tal muscles already formed. 



In the development from the bud to the scyphistoma there 

 is no stage comparable to an anthozoan. This is not an argu- 

 ment, however, against Goette's theory of the descent of the 

 scyphomedusa from an anthozoan- like ancestor, for one could 

 not expect a step in the phylogeny to be recapitulated in a 

 process of non-sexual development unless this process takes 

 place during a relabively earlier ontogenetic stage and the 

 budding in Cassiopea occurs on scyphistomas that have long lost 

 their anthozoan characters, if they ever possessed any. Goette 

 regards the early stages in the scyhphistoma as possessing es- 

 sentially anthozoan characters, in the ectodermal oesophagus 

 and the four gastric pouches. Glaus admits the existence of 



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