clinging to the trees while the wind spends its force. This is
particularly the case when the wind blows up at a late hour of the day;
then, on the following morning, the dragon-flies are seen clustering to
the foliage in such numbers that many trees are covered with them, a
large tree often appearing as if hung with curtains of some brown
glistening material, too thick to show the green leaves beneath.

In Patagonia, where the phenomenon of dragon-fly storms is also known,
an Englishman residing at the Rio Negro related to me the following
occurrence which he witnessed there. A race meeting was being held near
the town of El Carmen, on a high exposed piece of ground, when, shortly
before sunset, a violent pampero wind came up, laden with dense
dust-clouds. A few moments before the storm broke, the air all at once
became obscured with a prodigious cloud of dragon-flies. About a hundred
men, most of them on horseback, were congregated on the course at the
time, and the insects, instead of rushing by in their usual way, settled
on the people in such quantities that men and horses were quickly
covered with clinging masses of them. My informant said--and this agrees
with my own observation--that he was greatly impressed by the appearance
of terror shown by the insects; they clung to him as if for dear life,
so that he had the greatest difficulty in ridding himself of them.

Weissenborn, in London's _Magazine of Natural History_ (N. S. vol. iii.)
describes a great migration of dragon-flies which he witnessed in
Germany in 1839, and also mentions a similar phenomenon occurring in
1816, and extending over a large portion of Europe. But in these cases
the movement took place at the end of May, and the insects travelled due
south; their migrations were therefore similar to those of birds and
butterflies, and were probably due to the same cause. I have been unable
to find any mention of a phenomenon resembling the one with which we are