33 
must he the first to take up and the last to lay down. Until the 
entire subject of the life history, the relations, the economy, the 
development, and the conditions of health and disease, have been 
mastered, and without practical results—until they are, in fact, as 
well known as those of the horse, or the dog, we need not despair 
of measures of relief against it. In short, the importance and dit- 
ficulty of the subject are such as to call for the most patient, thor- 
ough and exhaustive research, before we abandon the contest as 
hopeless. 
It was in the spirit of these reflections, that | made a beginning 
upon the study of this insect, last July, and the first results of the 
season’s work upon it are here reported. As the chinch-bug has 
been somewhat fully treated by my predecessors, in previous reports 
from this office, I have not thought it worth while to summarize . 
the well-known facts respecting it, but will pass at once, without 
further explanation or apology, to an account, first, of its history 
during the present season; second, cf various checks upon its in- 
crease, some of them newly-discovered; and third, of certain arti- 
ficial measures for its destruction, upon which I have begun to ex- 
periment. 
LIFE H:iSTORY. 
The life histories of insects are the foundations of economic en- 
tomology; these must be complete, definite and accurate, or all 
else is indefinite and uncertain. And as the histories of insects 
vary, according to latitude, and from year to year, it 1s necessary 
that they should be studied in various localities, and under different 
conditions. Without the knowledge thus acquired, we can neither cor- 
rectly foresee the course of events respecting insect ravages, nor tell 
when and where we may attack their authors to the best advantage,— 
and yet, for various reasons, there is scarcely a single species of in- 
jurious insect whose life history is certainly and completely known. 
For lack of this definite and reliable knowledge, we are often left 
to grope in a fog, where we should see by the clearest light of day. 
The requirements of this subject are exceedingly simple. The secret 
of a successful method is, close and continuous observation. A species 
should be followed from week to week, and at times even from day 
to day, throughout the year, and through its periods of scarcity as 
well as through those of its greatest abundance. The area super- 
vised should be the largest which it is possible to cover thoroughly, 
and the time over which our observations are extended should be 
long enough to give us a knowledge of the variations from the av- 
ernae, due to differences of weather and other local or general con- 
ditions. 
Respecting the chinch-bug, a fairly complete life history, for an 
average year during its periods of abundance, has been made out, 
and some general knowledge has been gained of the bad effects of 
extremely wet weather; but beyond this we have not heretofore 
gone. 
As the year just closing has been in many respects an lereeprodal 
one, I have thought it worth while. to give a somewhat full sum- 
mary of our field notes on this insect, and we shall see that the 
