38 HDWAiiit T. iii:(iwm:. 



at least iloublc the uuiuher uf sense organs. I cuuld nut find a single specimen in the 

 cullection with the characteristic conical umbrella of 5. bitentaculata. S. mediterranea 

 is a colijurless Medusa, and Mr. Hodgson informed me that the ' Discovery ' specimens 

 were colourless when alive. S. bitentacubita, on the other hand, has reddish gonads 

 and tentacles, but the colour disappears after preservation. 



SOLMUNDELLA MEDITERRANKA. 



^HJginopsis mediterranea, .1. Miiller, is.")!, jt. 272, Taf. XI. ; Leuckait, IH.Ji;, p. 88, Tiif. II. ; MeUchnikofF, 

 1K74, Bd. xxiv., p. 2r,, Taf. IV. ; lluecki-l, 1«70, p. 8:.2 ; Lo Hiaiico, VM)\, p. .^C, Taf. XXXV., 

 fig. 142. 



Sohnumlella mmlilerranea, Maas, I'.IOG, p. 12, Taf. I. (fig. 5), Taf. III. (figs. 23, 24). 



Snlmiiiiilella mueUeii, Haeckel, 1879, p. 3r)2. 



Solmiiwlella /lenseni, Maas, 1893, p. 55, Taf. V., fig. 11. 



The ' Di.scovery ' collection cont^iins about 300 specimens of this species, liut only 

 a few are in a satisfactory condition, and all are more or less contracted. It was by 

 far the commonest Medusa in McMurdo Sound. In 1003 specimens were taken from 

 the middle of ^larch throughout the Antarctic winter up to the beginning of 

 November. Young and adult stages frequently occurred together, and apparently the 

 Medu-sa has no definite breeding season. 



In the ' Southern Cross ' collection tlierc are three specimens of Solmundilhi, 

 which no doubt belong to this species. They were taken at Cape Adare on lOtli 

 May, 1899. 



The umbrella is a little broader than high, with a rather fiat toj), about on a level 

 with the exit of the tentacles. The umbrella of the largest specimens measured 7 mm. 

 in diameter. Over the e.x-umbrella there are .scattered many small clusters of cells, 

 which are especially noticeable near the margin of the umbrella. These are ectodermal 

 cells containing many wcll-(lefincd granules, and amongst these cells are generally a 

 number of nematocyst.s. 



There are four perouial grooves in the wall of the umbrella. The groove below 

 each tentacle is of the normal type, but the groove in oacli of the perradii without 

 tentacles is in a rudimentary condition. Frof. Maas (1905), p. 72, figs. 74 and 75, 

 mentions and figures slight peronial grooves in the perradii without tentacles in 

 S. bitentaculata, taken by the ' Siboga ' expedition in the East Indies, and he includes 

 the presence of four radial grooves in the generic character. The specimens which 

 I examined of the same species taken off Ceylon (Browne, 1905, p. 153) did not show 

 a groove in the perradii without tentacles. 



The Antarctic specimens have very conspicuous grooves in the perradii without 

 tentacles. The grooves cut deep into the jelly at the margin of the umbrella, but the 

 length and depth of the groove show a considerable amount of variation. The 

 peronial band in each of the perradii without tentacles, after running alongside the 

 .sub-umltrella turns oft" at the level of the stomach to the ex-umbrella, where there is 



