THE AT AX HIS TRI ONI CUS. 
437 
mothers associate together very familiarly upon the smooth leaves 
of the water plants. The eggs are red, ovoid in shape, and are 
in myriads ; they are placed side by side, and are covered over 
with a mucous secretion, which protects them. It is not unusual 
to see one female after another choose the same spot for egg- 
laying, and to observe the number of egg-layers increasing hour 
after hour, so that a thick crust is formed at last on the plant. 
After a fortnight the. young larvse are hatched ; they are exces- 
sively small, and are of a brilliant red colour. They are hairy, 
and have six long legs, terminating in claws. These larvae swim 
with great rapidity, and often seek the surface of the water, and 
allow themselves to become dry ; then they run over the pond as 
quickly as if it were a solid surface. It is very probable that 
these six-legged larvae live as parasites upon the larvae and nymphs 
of dragon flies, May flies, and gnats ; and it is by no means 
certain that the adults of these flying insects are not attacked 
also. M. Duges believes that a second metamorphosis takes 
place during the adult stage, as in the genus noticed above. 
Some of the water mites do not swim, but are able to fix 
themselves on to other insects, and to crawl. Limnocharis 
aquaticus is one of them ; and it may be recognised in the adult 
state by its irregularly oval body, which is rather conical in 
front, very soft and capable of being altered in shape sponta- 
neously. The skin is reddish in colour, and the tints are brightest 
when the insect is young. There are no hairs, except on the 
legs, where they are not very commonly seen ; the eyes are 
large, close together, triangular in shape, and of a deep red 
colour, and they appear to be fixed on to a special scale-like 
piece of the body. The claws of the legs are large, retractile, 
and are made to hold on with, and not for swimming. 
The eggs are laid on the mud at the bottom of ponds, and 
look like a whitish incrustation tinted with red ; and small red 
larvae, with six long legs, oval bodies, and snout-like heads, come 
forth from them. These larvae run upon the surface of the water, 
or swim in the midst of it ; but they soon give up that sort of 
life, and select a host to be parasitic upon. Gerris lacustris is 
their favourite insect. It is one of the Hemiptera , and lives on 
the surface of stagnant waters, skimming over them with great 
