reachea to about half the length of the am the distal funnels 

 begin to subdivide. By this subdivision of the primary fun- 

 nels, funnels are produced of which some are the imdiments of 

 secondary branches , these subdivide ligain and so on as lon^ as 

 growth continues. The subdivision is not dicotymous, but 

 takes place in such a way as to produce alternate branches. A 

 vesicle is form.ed in some way at about the time of tiie comple- 

 tion of the fusion of the fold of the lip into a funnel. I 



have not been able to deteiTnine, so far, whether the vesicle 



I 



'is a funnel with the orifice closed as Hamann claims it to be, 

 or whether it is an evagination from the pedicle of a vesicle 

 as it seemed to me to be at first, and as Glaus thinks it pos- 

 sibly is. 



Accordir^ to Haeckel (1879) the genus Archirhiza repre- 

 sents a form th£it was the ancestor of all the rhizostomatous 



medusae. Of this genus there are two known species, A. pri - 



i 



mordiatis , Haeckel, and A. aurosa , Haeckel. They agree in 



having four subgenital cavities and eight simple unbranched arms 



[that are provided with a single zig-zag rav of closely set o- 



'l-al funnels and are devoid of other appendp^es. Hamann sr.ys 



Ihat a stage representing this condition is a feature of the 



ontogeny of rhizostomatous medusae. From wliat I have said it 



is evident that we have no such stage in the development of 



- 59 - 



