254 N. ANNANDALE: An Indian Freshwater Medusa. [Vov. VII, 
Manubrium.—The manubrium in most of Mr. Gravely’s and 
Mr. Agharkar’s specimens has the saucer-like form characteristic 
of the genus, consisting merely of a shallow ring and opening 
nearly as wide as the velum. In some few adult individuals, how- 
ever, it is in a more or less contracted condition, while in one 
young one (fig. I) its margin has been drawn together in such a 
way as to close the mouth almost completely, leaving only a 
minute star-shaped aperture. Mr. Gravely informs me that even 
the largest medusze ate quite capable of keeping their mouths 
closed, so long as they are in good health. 
Gonads.—The gonads surround the manubrium as in other 
members of the genus. In the male the testis forms a uniform 
opaque white ring, but in the female the ring is grooved vertically 
at frequent intervals so that it has a crimped appearance. The 
grooves extend from the upper part of the manubrium downwards 
Fic. 2.—Tentacles and sense-organs as seen from below, 0.=otocyst: p. t.= 
primary tentacle; s.t.=secondary tentacle; v.=velum. 
but do not reach its distal margin. They do not form distinct 
loculi in the ovary. for the ova, which are arranged horizontally, 
extend across them. A number of minute greenish cells (pos- 
sibiy symbiotic algae) exist in the outer covering of the ovary and 
give it a faint yellowish tinge. The eggs are very small; when 
ripe and apparently just about to be emitted from the ovary they 
are circular and from o'04 to 006 mm. in diameter. At an 
earlier stage they are produced and pointed at one side. 
Tentacles.—The tentacles appear, at any rate in the adult, to 
have a much more definite arrangement (fig. 2) than is the case 
either in L. tanganicae or L. rhodesiae. In general structure they 
agree with the tentacles of these species They may be divided at 
sight into two series that may be called primary and secondary ; 
those of each series having a distinctive structure, position and 
number. ‘The primary tentacles are much stouter at the base and 
