3°8 
THE TANGANYIKA PROBLEM. 
life cycle in Limnocnida , and this cycle is complete with- 
out any hydroid phase, in fact, no hydroid was ever found 
in the lake, although I searched persistently for them. 
This being so, the many peculiarities which the life-cycle 
presents are at once striking and significant. At the present 
time, however, I do not think it advisable to attempt to 
dilate upon the medusae’s proximate affinities, as I intend to 
return to this matter in a special memoir. But it may be 
useful to point out that the animal has most conspicuously 
primitive attributes, coming in this sense exactly into line 
with the halolimnic gastropods. It is certainly a marine 
derivative, probably from its life-history related to the 
Narco-medusae of the ocean. 
