48 Bulletin Vanderbilt Marine Museum, Vol. VII 



Order: RHIZOSTOMAE Cuvier 

 Rhizostomata dichotoma Vanhoffen, emended, Mayer 



Genus: CEPHEA Peron and Lesueur 

 Cephea cephea (Forskal) 



Type : Forskal's tjrpe was secured in "Djiddae" and deposited 

 in the Royal Zoological Museum, Copenhagen. 



Distribution : According to the various specialists working 

 with this group, this species and its several subspecies are widely 

 distributed in the Indo-Pacific, it having been recorded from the 

 Red Sea (Forskal), eastward to Malabar (Peron and Lesueur), 

 northward as far as Misaki, Japan, in winter, east to northwestern 

 Australia (Peron and Lesueur) , Samoa (Haeckel) , near the Mar- 

 quesas Archipelago (Boone) and the Hawaiian Archipelago 

 ( Agassiz ; Mayer ) . 



Material examined: Eight young specimens, taken in 150 

 fathoms, north of Nuka Hiva Island, Marquesas Islands, August 

 11, 1931, by the "Alva." 



Technical description : There are several excellent descrip- 

 tions of this species and varieties based on large adult, living speci- 

 mens. The "Alva" catch are all young, the smallest jelly-fish meas- 

 uring 10 millimeters diameter, the largest one 22 millimeters 

 diameter, the other six varying from 15 to 21 millimeters diam- 

 eter. These are particularly interesting in showing a serial varia- 

 tion in the wart-like ornamentation of the bell dome, but possess- 

 ing a constant identity with the other specific characters. In the 

 specimen 10 millimeters diameter, the dome is flattish and its 

 entire dorsal surface is regularly dotted with small, granular dots, 

 a few of which, about thirteen, incompletely ring the area which 

 becomes the typical dome. The ring furrow is incipient. There 

 are sixteen divisions of the marginal zone, thickened, opaque, and 

 sixteen long filaments. The subumbrella is developed, gelatinous, 

 and the characteristic long, tubular filaments are present. 



In the specimen 15 millimeters diameter, the dome is present, 

 well developed, with the near marginal warts reduced, the central 

 dome more definitely defined and the warts here longer, larger, 

 mammiform and more numerous and closely crowded. In the speci- 



