31 



many believed that they were leaving]; the coiiutry; but it was. 

 simply their mating season — the only time (twice a year) at which 

 they take the wing. Notes the fact that the cast skins of the in- 

 sect are often mistaken for dead bugs. Two insect enemies are 

 mentioned, — Hippodamia maculata (a common species of "lady 

 bird") and Chrysopa iUmoiensis (a species of the "golden-eyed 

 fly"). These insects were very numerous, — especially the former, 

 which could be counted by hundreds on every square yard of 

 ground after shaking the corn, — but they made very little impres- 

 sion on the chinch bugs. Found chinch bugs alive under snow 

 after several days of a temperature 15° or 20° below zero, but 

 dead if above the snow. In frozen corn husks they will live at a tem- 

 perature below the freezing point, and perhaps below zero. In 

 March and April, 1865, found a large majority of the hibernating 

 bugs alive. May 18 and 19, abundant in spring wheat, barley, 

 etc. Eggs laid latter part of this month, mostly on roots and 

 stalks beneath the ground. First larvae of the season seen June 10^ 

 millions of young bugs June 17, when parent bugs were princi- 

 pally dead. "July 16. Found many chinch bugs dying in the low 

 creek-bottom land from the effect of some disease, while yet in 

 the larval state. July 22. On low ground young chinch bugs all 

 dead from the disease, and it is spreading rapidly on the hills and 

 high prairies. Weather wet since first of July. July 28. Great 

 numbers in all stages of their development are dying of the pre- 

 vailing disease. Aug. 22. It is almost impossible to find even 

 a few cabinet specimens of chinch bugs alive." Says that 

 the parent chinch bug is about twenty days in laying about five 

 hundred eggs, and then dies, the imago appearing in from fifty- 

 seven to sixty days after the egg is laid; and that there are two 

 distinct broods in a season, and only two. The disease alluded to 

 was associated with long-continued wet and cloudy cool weather, 

 and was no doubt in some measure due to it. No attempt to de- 

 fine the direct cause. The disease was not confined to the chinch 

 bug. Considers it proven "that epidemic diseases are incomparably 

 fhe most important agents in all nature in destroying noxious in- 

 sects." Very difficult to find any chinch bugs in 1866. 



Shimee, Heney. — Additional Note on the Chinch Bug. (Proc. Acad. 

 Nat. Sci, Phila., 1867, v. 19, p. 234.) 



Mt. Carroll, 111., Sept. 16, 1867. "The chinch bug has entirely 

 disappeared from this region, so far as I have been able to ob- 

 serve. Efficient cause, the continuation of the epidemic among^ 

 them." 



1868. 



Peaieie Faemee, May 9, 1868, v. 21, n. s. p. 297. Birds I's. In- 

 sects. 



In this article (probably editorial) Dr. Henry Shimer is credited 

 with the following statement: "One hundred chinch bugs have 

 been found in the crop of a quail, when shot, and, in a season. 



