OX A FRESHWATER MEDUSA FROM RHODESIA. 
433 
and thirty-eight sense-organs to the quadrant; the umbrella 
of the complete medusa must have measured at least 12 mm. 
in diameter. 
A portion of the manubrium is also present, and this shows 
the animal to be sexually mature, an ovary being developed as 
abroad ring round the base of the organ (PI. 42, fig. 5). The 
ova seem ripe, and under high magnification appear polygonal 
Text-fig. 2. 
Part of the umbrella margin of Limnocnida rliodesise as seen 
from the exumbrellar surface. This figure shows the attach- 
ment of the tentacle -bases to the exumbrellar surface of the 
bell. r.c. Radial canal, t. Tentacle, p.t. Per-radial tentacle. 
ex. Exumbrellar surface of the bell, (x 45.) 
in shape ; the} r are provided with large clear nuclei, each with a 
distinct nucleolus (PL 42, fig. 6). 
The last of the four slides before me bears a fragment of a 
medusa, which must have had very nearly the same dimen- 
sions as the specimen just described. The umbrella margin 
is too macerated to allow me to make out anything of the 
