Vol. II, No. 4.] Notes on the Freshwater Fauna of India. 107 
[N.S.] 
is generally thrust into the air which is retained under the leaves 
of Pistia stratiotes, it is seldom possible to see it in use. The com- 
plexity and large size of the tubes are probably rendered neces- 
sary by the fact that the Beetle is liable to be detained beneath 
the surface for considerable periods. It is unable to sink without 
assistance; but when gorged with food it cannot rise readily, and 
is only able to ai foe up the stem or root of some convenient 
pac a apiaye Its ordinary method of feeding, moreover, “waged it 
to dro the bottom. Settling on the upper surface of the shell 
of any cneoveeeoaa water-snail which may approach its bites 
place, it inserts its minute head into the tissues of the animal from 
behind. The Mollusc retreats as far as possible into its shell and 
sinks to the bottom, carrying the Beetle with it. Here the latter 
feeds upon its victim at leisure. I have known an individ 
— aa because it could not rise to the surface after 
suc 
I hans ‘little doubt that this Glow-worm is the larva of some 
common fire-fly, possibly Luciola vespertina ; I do not think it is 
that of L. gorhami, an even commoner species in Calcutta, the 
female of which is winged and abundant. The structure of the 
ead, thorax and feet is essentially that of an ordinary larva of 
this genus. Possibly, heaven the aquatic igs may reach sexual 
maturity, in the case of the female, without leaving the water, 
and I have reason to think that the female does become mature 
th very little change of outward form. in my 
aquarium have, on several occasions, sunk to the bottom and died, 
after f ‘or some months, Their bodies were dis ed, and 
pons showed them to be full of eggs. Such imens had no 
te ernal geni — but were evidently about to undergo an ue 
eir integument being loose and easily separated and a ne 
Gael being already formed beneath it. 
a 
