SUBFAMILY OEDIPODINAE 63 
burnt over and covered with a tangle of blackened logs and stumps, 
we took twenty more; of these fifteen were blackish, three brownish, 
and two neutral, thus showing practically the same relative propor- 
tions. We have noted the same intermingling of forms along the 
shore of Lake Superior, near Duluth, but in our area the black ap- 
parently always outnumbers the others. 
The aerial stridulation of the males is a sharp crackling, very 
like that of the Arplias but much louder and more continuous. We 
once noted an interesting performance by three males at Biwabik. 
Out in the center of the railway switch yards, these three were grouped 
closely together and so intent were they that we were able to approach 
within a few feet without alarming them. First one would raise both 
hind femora high up and with a quick jerky movement rub them vig- 
orously against the sides of the tegmina; after a time he would pause 
‘and stand at attention while one of his mates took up the performance. 
To our ear no “music” was audible save a faint grating noise, far 
from melodious. This performance was repeated time after time and 
we do not know how long it might have continued had they not been 
interrupted by a heavily loaded ore train. As to the object of such 
demonstration, we have no explanation to offer since there were no 
females within a rod or more. 
In Tower and some of the other northern towns, this usually shy 
insect takes the place of Dissosteira in the streets and appears as thor- 
oughly at home there as the “Carolina locust”’ in the southern cities. 
At Tower we have noted that while it is abundant on the streets during 
the warmer part of the day, it disappears by about five o’clock in the 
afternoon and upon search we found it on weeds, posts, and other 
somewhat elevated places, apparently having retired for the night. It 
remained thus until rather late in the morning, not becoming active 
until nearly nine o’clock. While thus at rest, the insect is very slug- 
gish and does not start readily, making it easy to take such as may be 
desired. In the habit of poising motionless in the air, this insect also 
resembles Dissosteira and may be seen at times suspending itself in 
the air, much more like a butterfly in appearance than a locust. In 
northern Minnesota, this species matures about the first of July and 
may be found until killing frosts. We have taken it at Bemidji, Black- 
duck, Hibbing, Biwabik, Virginia, Vermillion Lake, Duluth, Taylor’s 
Falls, and Hinckley. It will probably be found throughout the area of 
the coniferous forests of our State. 
SUBFAMILY ACRIDINAE 
The members of the subfamily Acridinae may be readily distin- 
guished by the presence of a distinct spine, usually conical or cylindri- 
