46 



THE AMERICAN ENTOMOLOGIST. 



bristles or barbs of each whorl of the 

 plant are interspersed with softer ones, 

 which secrete a viscid matter attractive 

 to insects. Flies thrust the proboscis in- 

 to the harpoon-like bristles, and when 

 withdrawn the head is held fast. The 

 harder the backward pull, the more exten- 

 sive is the attachment to the sharp barbs, 

 and the head becoming congested, the in- 

 sect is seldom able to disengage it, and it 

 is twisted off by the gyrations made. — 

 Gardener s Monthly. 



THE CHINCH-BUG.* 



AMOUNT OF INJURY IT CAUSES. 



The Chinch-bug {Blissus leucopterus Say) 

 is unquestionably one of the most formid- 

 able insect pests with which the farmers 

 within the wheat producing area of the 

 United States have to contend. Although 

 not exceeding a grain of wheat in size, 

 rather slow-motioned and possessing no 

 other weapon of destruction than its tiny 

 slender beak, yet the species is enabled to 

 make up by number for the lack of indi- 

 vidual capacity for destruction. 



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 de- 

 struction than^does that of this diminutive 

 and seemingly insignificant insect." In 

 the territory east of the Mississippi it is 

 without a rival. 



Mr. Walsh estimated the loss from the 

 ravages of this insect in Illinois alone in 

 1850 at 4,000,000 dollars, an average of 

 $4.70 to every man, woman and child 

 then living in the State. 



Dr. Shimer says that it "attained the 

 maximum of its development in the sum- 

 mer of 1864, in the extensive wheat and 

 corn fields of the valley of the Mississippi, 

 and in that single year three-fourths of the 

 wheat and one-half of the corn crop were 

 destroyed throughout many extensive 

 districts, comprising almost the entire 

 Northwest, with an estimated loss of more 

 than 100,000,000 dollars in the currency 

 that then pr evailed." 



* From advance sheets of Bulletin No. 5, of the U. S. 

 Entomological Commission, by Cyrus Thomas. 



Mr. Thomas, in his second report, as 

 State Entomologist of Illinois, remarks as 

 follows in reference to the loss occasioned 

 by them in 187 1 : 



" I find no complaints of damage re- 

 corded in 1870, but as the summer was dry 

 over a large area, and they appeared in 

 immense numbers in 1871, it is more than 

 probable that they began to increase in the 

 latter part of the season." 



As Dr. LeBaron has noticed somewhat 

 fully in his second report their operations 

 in 1 87 1, it would be unnecessary for me to 

 do more than advert to it were it not for 

 the fact that this second report does not 

 appear to have been generally distributed 

 and is rarely seen. The following quota- 

 tion will suffice to show the extent and 

 severity of this visitation : 



" Some idea of the loss caused by the 

 depredations of this insect, in this and 

 neighboring States, may be realized when 

 we learn that over a belt of territory one 

 hundred miles wide, commencing in the 

 western part of Indiana, and extending 

 more than four hundred miles west, em- 

 bracing an area of more than forty thou- 

 sand square miles, the great staple of 

 spring wheat was reduced to not more than 

 a quarter of an average crop, and in many 

 places wholly destroyed ; and that over the 

 same territory barley was less than half a 

 crop, and oats not more than three-quarters 

 of their usual amount. 



" The center of this belt appears to have 

 been a little north of the center of the 

 State, being about on a line with the 

 junction of Iowa and Missouri, and taking 

 in a corresponding part of southern Iowa 

 and Nebraska, and of northern Missouri 

 and Kansas. South of this belt winter 

 wheat takes the place of spVing wheat and 

 barley, and the Chinch-bugs, though pre- 

 sent in considerable numbers, ceased to 

 commit any very serious damage. North 

 of this belt, also, notwithstanding that 

 spring wheat constitutes a leading crop, 

 the bugs became gradually less numerous, 

 and a tolerable crop of this grain was har- 

 vested. And yet all through northern 

 Illinois and the southern part of Wiscon- 

 sin, these insects were numerous enough to 

 damage the crop to some extent, and to 

 excite the most serious apprehensions for 

 the succeeding year. 



" In order to obtain as correct an idea 

 as possible of the amount of loss sustained 

 by the agriculturist from the depredations 



