89 
i gam occurred, the corn fields being now generally abandoned. The 
evelopmental period was consequently about two months, reckon- 
ig from the time when the last eggs were laid until the transform¬ 
ation of the last of the brood was complete. Concerning their hi- 
ernation, no new facts were elicited, except that they could not be 
>und in or about the fields where they had hatched. 
That the almost complete destruction or suppression of the spring 
mod was due to the prolonged and violent rains, there can be no 
lasonable doubt. The exact method in which rainy weather affects 
le bugs is, however, as yet undecided. That it cannot be simple 
lbmergence that destroys them is shown by a fact reported to me 
y Hon. Win. McAdams. In his vicinity, in Jersey county, they 
ere extremely abundant in the grain early in the spring, but were 
.1 apparently swept out of the country by a long and violent storm, 
ome days afterwards, when the water had subsided, he noticed in 
-filing over the drift wood in the river bottoms immense numbers 
‘ chinch-bugs among the rubbish, most of them still alive and 
•awling about. On the other hand, it seems unlikely that simple 
iposure to moisture has the effect attributed to rain. An experi- 
ent made at the laboratory bears upon this question, and will be 
orth reporting, although circumstances prevented its satisfactory 
>mpletion. A number of hills infested by the bugs were success- 
fily transplanted to boxes and variously treated with water for ten 
iys. Some selected examples were thoroughly drenched every day, 
>th ground and stalks ; in other boxes only the ground was watered ; 
still others the corn was sprinkled every day, but the ground 
'•otected; and the remainder were left with only sufficient attention 
keep the corn alive. During the time for which these experiments 
^re continued, no appreciable effect whatever was produced upon 
e bugs infesting the stalks. Those where the corn was watered 
3re washed down upon the ground each time, but soon dried off 
id climbed up the stalk. At the end of this time the bugs under 
•servation all commenced to disappear indiscriminately, without 
ference to the mode in which the corn had been treated, and the 
periment was thus abruptly closed. Enough was learned, bow¬ 
er, to show that a succession of heavy daily showers for more 
'an a week would have no appreciable effect upon these insects in 
»at stage. The weather was warm and pleasant, and the condi- 
>ns under which the experiments were carried on made it impossi- 
3 to saturate the air. Further light will be thrown on this ques- 
m by the facts detailed under the succeeding section. 
ti 
NATURAL ENEMIES. 
Insects. 
To many the subject of the natural enemies of injurious insects 
i ly seem unimportant, since the prospect of utilizing them for an 
ificial regulation of the numbers of destructive species is some- 
iat remote. But with regard to such insects as are still under 
i nstigation, no fact can be said to be unimportant, for the reason 
lit the most insignificant data may, for all that we know to the 
: ffrary, lead finally to the most useful conclusions. Further, a 
actical knowledge of the economy of the injurious species is not 
