66 THE OCEANIC HYDROZOA. 



contains two oblong, lateral cavities, besides that which lodges the swimming organ, and 

 one would be led by their figure to imagine that one of these cavities is a natatorial cavity, 

 and that tlieir Enneagonum is nothing but an ill understood "Aglaisma-form " of Ahijla. I can 

 testify that it is no easy matter to obtain a clear conception of the complex figure of the 

 singularly shaped hydrophyllium of this and other Cali/coj^Jwridce. 



Tlie genera Cymha and Cucubalus of Quoy and Gaimard appear to be Diphyozooids ; but 

 the figures and descriptions given by these naturalists are not such as to enable me to 

 arrive at any very confident opinion on this point. 



Gegenbaur (Beitrage, p. 9) carefully describes and figures a species, Biplophjsa inermis, 

 which appears to be very distinct from any of those enumerated above. However, it has 

 some resemblance to the Cucubalus of the French voyagers. 



