Notes on the Terinites. 89 
the last swarming of R. flavipes Kollar and at a time when the American 
Linden Tilia americana Linn was in full bloom. 
From the foregoing data it is apparent that the time when indoor swarm- 
ing occurs is independent of out-of-door conditions and is determined large- 
ly by the location of the nest in or beneath the building. The location of 
the nest of course determines the influence that the cumulative mean 
indoor tempartures and average relative humidity will have on it. Out- 
of-doors the time of swarming depends on the cumulative mean temperatures 
and the mean relative humidity. 
The swarming of termites in a building should in general be regarded 
as a danger signal. It is needless to say that it is a great annoyance to 
have these awkward colonizing adults aimlessly flying into one’s face or 
into any foods that are exposed. Yet during the past season we have 
found two cases where swarming took place and where careful inspection 
failed to reveal any damage to the buildings in which it occurred. Like- 
wise, we have found two infestations in buildings from which no swarms 
emerged. This naturally brings up the question as to the factors that 
cause a colony to swarm. These factors, though still imperfectly under- 
stood, are: (1) the kind of reproductive forms in the colony; (2) the age 
and size of the colony; and (3) the influence of instinct. 
The role of swarming in the life economy of a colony is another point of 
interest. In the case of early swarming indoors the value of swarming is 
hard to see as practically all the adults emerging, if they are not killed, 
perish. This is because conditions necessary for the establishment of new 
colonies are seldom present. Out-of-doors the opportunities for the found- 
ing of new colonies are greater. But even out-of-doors immense numbers 
of colonizing adults perish. On May 26th practically all termites R. flavipes 
that emerged were eaten as soon as they issued by a large flock of sparrows 
that gathered for the oc asion. In the swarming of R. virginicus on July 
1st it was observed that adults alighting on the ground were immediately 
snatched up and dragged off by the workers of the common corn-field ant 
Lasius niger Linn. var. ymericanus Emery. 
Termite Injury. 
The injury that Indiana termites do is of two kinds, namely that which is 
done to buildings and their contents and that which is done to living 
plants. The members of the genus Reticulitermes are subterranean 1n- 
sects. Under normal conditions in nature they feed on stumps, logs, and 
wood debris, straw, manure. and leaves. But with the advance of civiliza- 
tion much of the food of termites has been removed, forcing the insects 
either to retreat before this advance or to adapt themselves to the new 
order of things. They haye chosen the latter course to a certain extent, at 
least, as is shown by the injury they do to living cultivated plants and to 
buildings and their contents. These insects are justly classed among our 
most destructive wood-borers. 
There is one thing that is absolutely essential for a colony of Indiana 
termites to maintain itself and that is a ready access to moisture. This is 
obtained from the ground. Given a constant supply of moisture these 
insects are able to tunnel in the comparatively dry woodwork of buildings 
