BROWNE— MEDUSA FROM THE INDIAN OCEAN 187 



thickening of the sub-umbrella. Mouth with four lips. Gonads close fo the margin of 

 the umbrella and extending over about one-quarter the length of the radial canals. 

 Tentacles, 14 — 16, with globular basal bulbs. One or two sensory vesicles between every 

 two tentacles, very minute and probably have contained only one otolith. 



20. Phialidium sp. B. 



Locality. Amirante Isles, Surface (Temp. 79° F.). 9 Oct. 1905, gg. 6 specimens. 

 Surface. 17 Oct. 1905, oo. 3 specimens. 



Umbrella hemispherical, 5 — 6 mm. in diameter. Gonads close to the margin of the 

 umbrella, linear or oval sacs extending over about one-quarter the length of the radial 

 canals. Tentacles, 30 — 40, with globular basal bulbs. One to three sensory vesicles 

 between every two tentacles. 



21. Irene sp. ? A. 



Locality. Nazareth Bank, Cargados Carajos, Surface. 30 Aug. 1905, g. 

 1 specimen. 



This is an early stage without gonads. The umbrella is about 6 mm. in diameter 

 and very thin. The stomach is small and upon a short peduncle. There are eight 

 tentacles, with globular basal bulbs, and three to four marginal bulbs between every two 

 tentacles. All the bulbs have a pair of cirri adjacent to them, and excretory pores are 

 visible. A few sense organs were found, and there is probably one between every two 

 marginal bulbs and tentacles. 



'■in'- 



22. Irene sp. ? B. ■ 



Locality. Saya de Malha Banks. 58 — fms. 6 Sept. 1905, C, 14. 11 specimens. 



These specimens are all in bad condition, so that only a general description can be 

 given just to indicate that the Irene-like medusa occurs in that district. Their umbrellas 

 measured 30 to 40 mm. in diameter and are moderately thick. From the centre of the 

 umbrella hangs down a broad thick peduncle, about 20 mm. in length. Upon it a broad 

 stomach is situated, and its mouth has four lips with the margin closely folded. It 

 is a large mouth even in a contracted condition. There are four radial canals. 

 The gonads, some containing well-developed ova, form laminar bands along the canals 

 upon the sub-umbrella, but they do not extend down the peduncle. Some of the 

 specimens have the above-mentioned organs in fairly good condition, but all have the 

 margin of the umbrella, either completely denuded of its appendages or in such a frag- 

 mentary condition that not even one quadrant is complete. I consider there should have 

 been fifty or more tentacles, about three marginal bulbs between every two tentacles, and 

 at least one small sensory vesicle between every two bulbs. Exci-etory pores are visible 

 in connection with the basal bulbs of the tentacles and the marginal bulbs. I can find no 

 definite indication of marginal cirri. The margin is not only broken but has rather 

 a macerated appearance, therefore it is not advisable to describe it in detail or base 



drawings upon it. 



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