THE COAST OF CALIFORNIA. . Ill 



MlCROCAMPANA CONICA geil. et Sp. ROV. 

 (PLATE IV, FIG. 8.) 



This interesting medusa was collected under the lofty 

 cliffs of Punta Diablo on Santa Cruz Island. It differs 

 from others in the possession of six radial tubes and a 

 simple club-shaped tentacle. 



The number of radial tubes among the medusae of the 

 AnthomedusaB is generally constant, four or multiples of 

 four. The majority of genera have four of these tubes ; 

 some have eight and more, while but one or two are said 

 to have six. Four is the constant number which prevails 

 even through the Siphonophora and its multiple is an al- 

 most constant feature among the so-called Discophora. 

 The genera with six radial tubes are marked ones as in- 

 troducing a new unit in an almost universally quadruple 

 series. 



The other structural features of Microcampana are dif- 

 ferent from those of any hydroid genus with six radial 

 tubes, while the character of the tentacle is very excep- 

 tional. 



The bell is asymmetrical, conical, smooth, transparent, 

 with a long conical apical protuberance. Clusters of ne- 

 matocysts are irregularly scattered upon its outer surface. 

 The apical protuberance of the bell recalls a similar ap- 

 pendage in Saphenia, Stomatoca and Amphinema. 



The bell has six radial tubes, a marginal vessel, and an 

 apical tube or funiculus ending blindly in the apical prom- 

 inence. The radial tubes are narrow and simple without 

 lateral branches. 



The marginal appendages to the rim of the bell are of 

 two kinds. At the peripheral end of five of the radial 

 tubes there are simple projections or protuberances, which 

 are densely pigmented. From the extremity of the re- 

 maining radial tube there hangs a club-shaped tentacle 

 which recalls in structure the tentacles of the genus Di- 



