12 
Outside the tar line, myriad? of young bugs just from the egg 
were moving southward in the direction of the adjoining corn (C, 
PI. II.), nearly covering the ground in many places. Not a 
single insect attempted to cross the tar, although in their confu¬ 
sion they scrambled about in all other directions; but where no 
barrier intervened they passed rapidly along towards the corn. 
Two thirds of the bugs within the oval had collected at either 
end by 3:30 p. m., and about two thousand had fallen into the can. 
At 4:30 p. m. the barrier was in good condition except at one 
place where the coal-tar had been poured over the loose ground 
and was now getting quite dry. A few insects attempted to cross 
the line, but either retreated or went pell-mell into it and were 
destroyed. One third of the entire lot had collected in the east 
end, and the others were scattered about the oval. About five 
thousand were taken from the can, and the experiment was left 
over night. 
July 14, at 9:30 a. m., of the twenty-one thousand bugs left in 
the oval the previous night, less than two thousand remained, one 
half of these being in the can. The remainder had escaped dur¬ 
ing the night and early morning tlnxmgh a passageway at the east 
end where the tar had become dry, and where the wind had blown 
line particles of dirt over the surface, completely covering it. 
At 10 a. m., sky clear and a gentle westerly breeze. Tempera¬ 
ture of air 84"; surface 106"; soil 117"'. 
No. 6. July 10, a strip of ground between the spring wheat (B, 
Plate II.) and corn (O) three feet wide, was thoroughly and 
deeply pulverized hy means of a harrow-toothed cultivator, and a 
twelve-foot plank drawn endwise, the driver riding the harrow or 
plank when necessary. Next, a log about six feet long and eight 
inches through was dragged endwise back and forth in this strip, 
the driver riding it, until a deep furrow had been made. The 
sides of the furrow were then dressed up here and there with a 
hoe. 
►Similar furrows were made in the fifth and sixth rows, and a 
narrow line of coal-tar was poured along the bottom of the furrow 
in the latter row, from an ordinary two-gallon sprinkler without 
the nozzle. On the first application one gallon of tar was suffi¬ 
cient for a line ten rods long, and thereafter for about twenty rods. 
The tar very soon formed a crust, but remained in good condition, 
and completely checked the advance of the chinch-bugs for twenty- 
four hours or longer. 
Holes about a foot deep were made in each furrow with an or¬ 
dinary post-hole digger at intervals varying from ten to twenty 
feet, according to the abundance of the bugs. 
A strip of winter wheat (A) of about four and a half acres, 
badly infested with chinch-bugs, was cut June 27 to July 3. The 
bugs then attacked a narrow strip of spring wheat (B),—about 
one rod wide, running the entire length of the field,—which they 
-completely ruined. This was cut July 7 and burned over the fol¬ 
lowing day. Many bugs were destroyed, but the great majority of 
them moved into adjacent corn (C), blackening the stalks in the first 
two or three rows. 
