BROWNE— MEDUSA FROM THE INDIAN OCEAN 195 



Peros Atoll. 75 — fms. 30 June, 1905, M. 1 specimen. Amirante Isles, Desroches. 

 100 — fms. 16 Oct. 1905, kk. 1 specimen. 



Mayer (1910) has revived the old generic name Sminthea of Gegenbaur and defines 

 the genus as follows : — " Trachymedusse with only eight tentacles, one at the foot of each 

 of the eight radial canals. In other respects this genus is similar to Rhopalonema." 

 The chief advantage in the use of the name Sminthea is that it has a good type species, 

 known as Smirithea eurygaster. It is quite easy to recognise this species when the 

 gonads are present as they form globular swellings on the radial canals adjacent to the 

 margin of the umbrella. In the early stages with the gonads undeveloped, it is necessary 

 to rely upon the absence of any intercanal tentacles or cirri, and take the risk of their 

 being early stages belonging to another genus. 



The specimens in the "Sealark" collection are between 2 to 3 mm. in diameter and 

 some have gonads. The tentacles are all broken off at their base. 



This is rather a rare medusa. It has been previously recorded from the Mediterranean 

 and the Atlantic. Its southernmost record in the Atlantic being in the South Equatorial 

 Current off the north coast of Brazil. 



31. Pantachogon bubrum, Vanhoffen, 1902. 



PantacJiogon rubrum, Vanhoffen, 1902, p. 63, Taf. 9, fig. 9, Taf. 10, figs. 19—20. 

 Pantachogon rubrum, Maas, 1905, p. 55, Taf. 10, fig. 66. 

 Pantachogon rubrum, Mayer, 1910, p. .389, text-figs. 240 — 241. 



Localities. Chagos Archipelago, off Peros Banhos, 600 — fms. 30 June, 1905, N. 

 1 specimen. Between Providence Is. (Fai^quhar Group), and Alphonse Is., Lat. 8° 16' S., 

 Long. 51° 26' E. 900—0 fms. 6 Oct. 1905, aa. 1 specimen. 



Unfortunately both specimens are in bad condition, but it is just possible to determine 

 the species. The umbrella is dome-shaped, with an evenly rounded summit, about 7 mm. 

 in width and 5 mm. in height. The stomach is about 2 mm. long, without a peduncle, and 

 its mouth has four short lips. The gonads are evidently just beginning to develop on the 

 lower half of the eight radial canals. The tentacles are indicated by their stumps, and 

 there are evidently eight in each octant. 



The second specimen is of about the same size and shape as the first one. It is, 

 however, in far worse condition, but useful as it shows a certain amount of bright 

 reddish coloration on the sub-umbrella. 



Distribution. Widely distributed in the warm regions of the Atlantic and Indian 

 Oceans, and belonging to the mesoplanktonic zones. 



32. Halicreas papillosum, Vanhoffen, 1902. 



Halicreas papillosum, Vanhoffen, 1902, p. 68, Taf. 9, figs. 7—8, Taf. 11, fig. 30. 



Halicreas papillosum, Maas, 1905, p. 57, Taf. 10, fig. TO, Taf. 11, fig. 71. 



Halicreas papillosum, Bigelow, 1909, p. 138, pi. 3, fig. 3, pi. 33, figs. 8—9, pi. 34, figs. 1—3, 5, 8, 10, 11. 



Halicreas papillosum, Mayer, 1910, p. 391, figs. 242 — 243. 



Localities. South of Farquhar Group, Lat. 10° 27' S., Long. 51° 17' E. 1000—0 fms. 

 27 Sept. 1905, q. 3 specimens. North of Farquhar Group, Lat. 8° 16' S., Long. 51° 26' E. 



25—2 



