BROWNE— MEDUSA FROM THE INDIAN OCEAN 



197 



Most of the specimens are in good condition and resemble figures given by Maas 

 (1893, Taf. 1, figs. 12 — 14). The umbrella having its length greater than its width, but 

 in a few the length and width are about equal. None exceeded 3 mm. in length. The 

 peduncle showed great variability in its length. In some specimens it is scarcely visible 

 owing to contraction, whilst in others it reaches halfway down the cavity of the umbrella. 

 The gonads at an early stage are globular, and become cylindrical or sausage-shaped when 

 fully grown. 



84. Amphogona apsteini (Vanhofifen) 1902. 



Pantachogon apsteini, Vanhoffen, 1902, p. 65, Taf. 10, fig. 18, Taf. 11, fig. 28. 

 Amphogona apsteini, Browne, 1904, p. 740, pi. 54, fig. 5, pi. 56, fig. 1, pL 57, figs. 10 — 15. 

 Amphogona apsteini, Bigelow, 1909, p. 126, pi. 2, tigs. 1 — 2, pi. 34, figs. 12 — 15, pi. 45, fig. 10. 

 Amphogona apsteini, Mayer, 1910, p. 405, text-fig. 257. 



Localities. North of Chagos, Surface. 18 May, 1905, H. 1 specimen. Cargados 

 Carajos, Surface. 30 Aug. 1905, i. 3 specimens. Farquhar Group, Surface. 2 Oct. 

 1905, X. 5 specimens. 



Hermaphroditism occasionally occurs in this species and as such a feature is very rare 

 amongst the Hydromedusse it breaks the monotony of the usual descriptions. T first 

 noticed (1904) in specimens collected by Professor Gardiner from the Maldives Islands; 

 the male and female gonads alternating with one another in the radial canals. 



Bigelow on the cruise of the " Albatross " in the Eastern Pacific found six specimens 

 in Acapulco Harbour. These specimens turned out to be unisexual, all the gonads of any 

 given individual being either male or female. 



Hartlaub (1909, p. 462, Taf 21, fig. 27) has described a new species under the name 

 of Amphigona pusilla from Djibuti in the Gulf of Aden. One specimen shoM^ed herma- 

 phroditism, and the other was unisexual and female. 



In the " Sealark " collection one specimen shows three gonads, similar in shape and 

 size on adjacent canals, and they have every appearance of being males, so it may be 

 presumed that this specimen is unisexual. Another specimen shows large and small 

 gonads alternating with one another, as figured by Vanhoffen, but they are too immature 

 for the determination of the sex. The other specimens have either lost or nearly lost 

 all their gonads and are useless for this purpose. 



The specimens are about 2"5 mm. to 4'5 mm. in diameter, and have their stomach 

 upon a peduncle, which varies in length according to the size of the specimen and the 

 amount of contraction. The smallest specimen has about six tentacles, and the largest 

 eight tentacles in each octant. The sense organs have all disappeared. 



Distribution. Previously recorded from Indian Ocean, Maldive Is. ; West coast of 

 Sumatra. Pacific Ocean ; Acapulco Harbour (Mexico). 



Genus LiRioPE, Lesson, 1843. 



This is a difficult genus for finding reliable specific characters. The character which 

 has usually been selected is the shape of the gonads. If the gonads be taken for the sole 

 character, then it is possible to connect together specimens with linear gonads, through 



