HYDROID PHASE OF LIMNOCODIUM SOWERBYI. 507 
Notes on the Hydroid Phase of Limnocodium 
Sowerbyi. 
By 
G. Herbert Fowler, B.A.Oxon., Ph.D., 
University College, London. 
With Plate XXXII. 
THOUGH it is now nine years since the discovery of Limnoco- 
dium in the Victoria Regia tank of the Royal Botanic Society 
in Regent’s Park, no certain knowledge of the course of its 
life-history has yet been obtained, owing to the peculiar cir- 
cumstances under which it occurs, and to the briefness of its 
annual existence. For various reasons I have only attempted 
the problem from one side; with the view, namely, to deter- 
mine whether an already known hydroid polyp occurring in 
the same tank with the medusoid bore any relation to it or 
not. 
The medusoid reappeared on May 10th, 1888; débris of all 
sorts was at once collected from the tank, in which the 
hydroid was found in quantities. By great good fortune, in 
the course of the following day two specimens of the hydroid 
were found to be undoubtedly throwing off medusoids. Of 
these, the one isolated in order to undergo further develop- 
ment died shortly, and was not available for minute examina- 
tion; the other was at once preserved. Further material, 
comprising several hundred specimens of the hydroid, was 
constantly examined till the end of July, 1888; but no further 
gemmation of medusoids took place. As, in spite of constant 
