156 SECOND REPORT OF THE STATE ENTOMOLOGIST. 



subsequently obtained by me upon the farm of Mr. King. At least 

 twenty per cent of the entire number were of this form. The varietal 

 name given it by Dr. Fitch is misleading, for none of them probably are 

 wingless. Both the wing covers (hemelytra) and wings are very much 

 shortened — the former usually to about one-half the normal length, 

 and the latter to not much exceeding one-third. In figure 40, the 

 relative size of the two is shown, together with the structure of each, 

 from preparations and careful camera drawings made for this paper by 

 Mr. C. E. Beecher. As the drawings are intended to represent structure 

 only, the characteristic pigment spots and markings of the wing-covers 

 are not given. Their coriaceous portion shows numerous short hairs, 

 not extending beyond — the crinkled lines appearing elsewhere, and upon 

 the wings, resulting from the unequal distension of the wing-membranes 

 by the nerves. A comparison of the nervulation in the two forms 

 cannot fail of being of interest to the student 



Injuries of the Insect. 



The chinch-bug is beyond all question one of the most destructive of 

 our insect pests. It has been justly said of it: " The locusts of the west 

 are the only creatures of this class which exist within the bounds of our 

 national domain, whose multiplication causes more sweeping destruction 

 than does that of this diminutive and seemingly insignificant insect." 



Another writer, who has given it patient study, has remarked of it: 

 " It is the most dangerous insect foe with which we have to deal. That 

 it taxes them more heavily than all other such enemies combined, is 

 burnt into the convictions of thousands of farmers by repeated heavy 

 losses and bitter disappointment " (Forbes). 



Throughout the Southern and Western States, or more properly, those 

 lying within " the wheat-belt region," the chinch-bug is a well-known 

 and dreaded enemy, from the almost incredible amount of injury which 

 it inflicts, in certain years, upon the grain and corn crops. Probably 

 the aggregate of pecuniary losses which have resulted to the United 

 States from its ravages have considerably exceeded those inflicted by 

 any other of our thousand insect pests. 



That some idea may be had of the amount of these losses, a few of 

 the more reliable estimates that have been made are herewith pre- 

 sented. 



Mr. Walsh estimated the loss from the insect in Illinois alone, in the 

 year 1S64, at over $73,000,000, while a careful computation made by 

 Dr. Shimer, for the same year, showed that in the extensive wheat and 

 corn-fields of the valley of the Mississippi, three-fourths of the wheat and 

 one-half of the corn was destroyed at a loss of more than $100,000,000, 

 in the currency that then prevailed. 



