214 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 
The gall is large, greenish-yrllow. entirely open In-low and slightly convex above. 
The hollow is densely tilled with brown pubescence. The form is variable but the out- 
line usually regular. The surface is smooth, or slightly roughened by the reinlete. 
Some of these galls grow downward instead of upward and form brown velvety buttons 
on the under side of the leaves. specimens measured were from .1 inch to .4 inch in 
diameter. Thirty galls have been counted on one leaf. This is a common gall in 
northern Illinois and Indiana, and has been found occasionally in central part of 
Illinois. ^H. Garman in Forbes 1st Sep. Ius. Illinois.) 
The following uotes have been supplied by Professor Riley: 
Found August 9, 1878, on the upper side of the leaves of chestnut oak large irregu- 
lar swellings which on the under side are entirely open and closely covered with 
fine brownish hairs. Upon examination quite a number of white mites were observed 
actively running about in these hairy depressions. 
Some oak leaves were received from H. G. Hubbard. Crescent City, Fla., upon 
which were the blister like gall of some mite. Some of these galls are round, while 
others are irregularly oval, swelling on upper side of leaf — deeply depressed or con- 
cave beneath the concavity filled with long pink-colored hairs. (Unpublished notes.) 
304. Thk post oak locust. 
Dendroteitix quercus. Riley MS. 
The following account of this locust is taken bodily from Lawrence 
Bruner's report on locusts in Texas during the spring of 1886, Bull, 
^o. 13, Div. of Entomology, Dept. of Agr., 1887, p. 17-19: 
In addition to the several species of locust that have been mentioned in the pre- 
ceding pages, last summer for the first time another species of locust was noticed in 
vast numbers among the post-oak timber lying between the towns of Washington 
and Brenham, in Washington County. These were so numerous in one locality that 
they completely defoliated the trees of the forest, even to the very topmost twigs. The 
region occupied by this insect, although not over a mile and a half in width by 7 or 
8 miles in length, is sufficiently large for the propagation of swarms capable of devas- 
tating a much larger area during the present spring and summer, and by auother 
year to spread over several of the adjoining counties. 
Although there is at present no apparent injury to the trees thus defoliated last 
year, and now in progress again this year, there can be no question as to the final 
result if these attacks are continued for several years longer. The trees will event- 
ually die. While up to the present time this locust has shown a decided arboreal 
habit, it may, and undoubtedly will be, obliged to seek food in the adjoining fields 
when compelled to do so through lack of its present diet, which is rapidly disappear- 
ing before the hungry myriads of young locusts. 
Notwithstanding the great numbers of the foregoing described species which 
together have combined in injuring the cottou and corn crops throughout thifl and 
adjoining counties, it is my opinion that the present species is more to be feared in 
the future than they, on account of its arboreal nature aud the difficulty of getting 
at it in order to destroy it. To kill these locusts either while feeding among the foliage 
or " roosting'" upon the topmost boughs of the tall trees would be next to impossible. 
Ou the other hand, the other species are easily to be gottou at and destroyed, as just 
shown. 
The habits of this locust, as nearly as I was able to learn through inquiry from 
others, and by personal observation, are briedy as follows: 
The egg-pods are deposited in the ground about the bases of trees or indifferently 
scattered about the surface among the decaying leaves, etc.. like those of all other 
