muscles extend to the foot, Lhe septa remain ^hort, occupying 

 only the upper part of the calyx. The septal funnels are a- 

 bcrtive and ao not become the subgenital cavities. 



The strobilization is monodiscous and the basal segment 

 is regenerated into a scyphistoma. In this I at-;ree with lioet- 

 te. The free segment is very different in appearance from an 

 ordinary ephyrula. Stylorhiza must have a similar one. Ltn- 

 denfeld (1884) found young specimens of this genus witli twent^r- 

 four I'liopalia. In older ones the number is reduced to six- 

 teen and fin.-^Jly to eight. In Cassiopea the number of rhopa- 

 lia is constant in each individual, and depends on the number 

 of tentacles in th'; scyphistoma stage. There are, as a rule, 

 half as many rhopalia as there wore tentacles, every alternate 

 tentacle havir^ given rise to a rhopalium. The irregularities 

 in the marginal sti'uctures of the adult^that are so strikingly 

 frequent, ai'e to be referred back to irregularities in the ar- 

 rangement of the tentacles of the larvae from which they are 

 developed. 



The young medusa has at first a simple quadrate mouth 

 with slightly spreading lips. Later these are drawr. out into 



eight lobes so that as far as the mouth parts are concerned we 



I 

 have an Aurosa strge. 



There is no Archirhiza stage in Cassiopea but there is a 

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