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Mr, Norman II. Joy on the 
able speed, sometimes almost straight, sometimes in a 
series of curves. During the skimming the front legs are 
held either doubled up, or spread out, as in the position 
of a well “set” insect. The middle and posterior legs are 
held close to the sides. When the beetle gets to shore it 
dries itself carefully, curling its abdomen upwards, and 
using its middle and back legs. I have seen it frequently 
when on a leaf or some other floating raft enter the water 
and deliberately swim to the bank. At times, especially if a 
beetle has been kept for some time in a wet tube, it appears 
to become waterlogged and remains at the bottom of the 
water with its legs doubled up, and probably drowns. I 
have confirmed the experiments of the above observers by 
cutting off the end of the abdomen. A careful study of the 
glands and the fluid they secrete would be of great interest. 
I have little doubt the glands are analogous to those of 
Bemhidium and Myrmedonia. 
I have experimented with a fair number of other 
species of Coleoptera, especially of the genus Stemts. It 
seems probable that most of the latter are able to “skim,” 
but some do it far more readily than others. It is import¬ 
ant to experiment on these insects directly they have been 
captured, and with as little handling as possible, as a 
negative result would be of no value if they have been 
“ bottled ” for some time. Of the species with which I 
have experimented perhaps S. guttula is the most expert 
“ skimmer ”; it moves so rapidly on the surface of the 
water that it is really difficult to follow with the eye. 
S. hipundatus also skims very readily, especially on a sunny 
day. By repeatedly and quickly throwing a specimen out 
as soon as it had got to shore I computed that it had 
skimmed quite twenty feet before I lost it, when, however, 
I think it was almost exhausted. This species when washed 
out by throwing water on to the bank at the side of a pond 
took deliberately to the water and “skimmed” to another 
part. 
Of other members of the genus Stemis I have experi¬ 
mented with the following : — 
S. ossmm, S. Jlavipes, S. picipes and S. tarscdis skimmed 
more or less strongly on several occasions; the last very 
easily freed itself of the water and floated on the surface. 
These species did not generally start skimming at once, 
and often required some slight stimulation. I failed to get 
S. juno to skim, but when the last segment of the ab- 
