214 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 



The gall is large, greenish-yellow, entirely open below and slightly convex above. 

 The hollow is densely filled with brown pubescence. The form is variable but the out- 

 line usually regular. The surface is smooth, or slightly roughened by the veinlets. 

 Some of these galls grow downward instead of up ward 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 Ist Rep. Ins. Illinois.) 



The following notes have been supplied by Professor Kiley: 



Found August 8, 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 (Unpublished notes.) 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. The post oak locust. 

 Dendrotettix 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. 

 No. 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 another 

 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 cotton and corn crops throughout this 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 and 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. 

 On the other hand, the other species are easily to be gotton 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 briefly 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 



