Medusa? of the Philippines and of Torres Straits. 

 Chrysaora melanaster Brandt. 



179 



Chrysaora melanaster, BRANDT, 1838, Mem. Acad. Sci. St. Petersbourg, Sci. Nat., ser. 6, tome 4, 

 p. 385, Taf. 16, 17 



There is a well-preserved specimen of this medusa from Station D 5461, 

 June 14, 1909, San Miguel Bay, east coast of Luzon, depth 11 fathoms. The 

 bell is about 130 mm. in diameter and slightly flatter than a hemisphere. There 

 are 16 radiating spoke-like streaks of faint umber color extending from near 

 the apex of the exumbrella to the bell-margin in the radii of the 16 cleft velar 

 lobes. These 16 streaks occupy depressed radial areas sunken below the 

 general level of the contour of the exumbrella, and they are besprinkled 

 coarsely with wart-like nematocyst clusters of cinnamon-brown color. 



There are 8 rhopalia, 3X8 tentacles, and 6X8 marginal lobes. The velar 

 lobes are cleft as in Brandt's figures and are nearly similar in shape and size 

 to the ocular lappets. They are, however, not narrower at the base than out- 

 wardly, as in Brandt's figures, but are oval and taper quite regularly from 

 base to tip. 



FIG. 2. An octant of the bell-margin of Chrysaora melanaster, from exumbrella side. 



The tentacles are short and slender, the longest being not over 60 mm. 



The mouth-arms are long and slender, folded complexly, and about 170 mm. 

 long. The gonads are well developed, apparently mature, and protrude 

 through the subgenital ostia, the subgenital ostia being fully twice as wide as 

 the perradial columns between them. Thus each ostium is 28 mm. long 

 (circumferentially) and 15 mm. wide (radially), while the perradial columns 

 of the mouth-arms are only 13 mm. wide. 



In formalin the general color of the medusa is milky custard-yellow, the 

 gonads being lighter. The apex of the exumbrella is besprinkled with cinna- 

 mon-colored nematocyst warts, and the 16 radial streaks of light umber color 

 are also besprinkled with brown-colored clusters of nematocysts. This medusa 

 is widely distributed over the north Pacific from Kamtschatka to California, 

 but this Philippine Island specimen is the first which has been obtained in the 

 tropics. 



