57 
able that they were related to this destruction of the bugs. Thii 
conclusion was supported by the fact that they were more abundan 
m old bugs than in young, while the mortality referred to evidenth 
also chiefly affected the older individuals. It was found easy t( 
cultivate the bacterium artificially in organic infusions, but n< 
opportunity offered to apply it to healthy insects. Until this exper 
iment is made and the effects carefully studied, it must remaii 
'possible that the coincidence noted was merely accidental, and of n< 
particular significance. 
Another parasite discovered is similar to that well known as * 
common enemy of the house fly, and belongs to the same genu 
( Entomophthora ). This attacks both old and young chmch-bugs, ant 
finally embeds their bodies in a mass of mold. There is some reasoi 
to believe that this was the active agent in an immense destructioi 
of chinch-bugs which occurred in Northern Illinois in 1868, as describ 
ed by Dr. Shimer, of Mt. Carroll. Evidence is adduced of the possi 
bility of artificially cultivating this parasite also, and applying it tc 
the destruction of insects. 
TOPICAL APPLICATIONS. 
Topical applications for the destruction of insects are often of th< 
highest use to the horticulturist, whose crops are much more valu 
able per acre than those of the farmer, and both require and repa? 
much more careful and continuous personal supervision and manua 
labor. 
In agriculture, however, such measures have necessarily been o 
little service, especially where farms are large and the work is don< 
principally by machinery. To attempt to destroy the chinch-bugi 
of any considerable territory by the direct application of even tli< 
cheapest substances, would involve an amount of additional labo: 
which could not be had all at once in the country, no matter hov 
profitable its employment might be. The small farmer has, however 
a certain very decided advantage in fighting insects, over one wh( 
cultivates the soil on a large scale; and to him a substance which, 
at small cost, shall destroy the bugs in his wheat and corn, maj 
make the difference between a total loss of his income for the yeai 
and the preservation of his crops at the expense of a little additional 
labor and outlay. The manner in which the chinch-bug most com 
monly invades the corn-field, entering it on foot from one side whih 
yet unable to fly, and attacking first the outer rows, affords abou' 
the only opportunity to resist its assault upon the corn. Here its 
advance has often been checked by boards set on edge and daubec 
with coal tar, or by plowing and harrowing frequently a strip alon£ 
the field, which the bugs find it difficult to cross. Here, also, topical 
applications may be used with fair prospects of usefulness. If at¬ 
tacked while congregated in a comparatively small space, and before 
they have spread throughout the field (as they will usually do as 
soon as they have acquired the power of flight) the bugs may be 
exterminated before they have had an opportunity to do very seri¬ 
ous damage, provided that some inexpensive substance of easy 
application may be found to destroy them. 
