47 
to regret in their annihilation; I neglected to obtain a good supply 
of specimens, while they might have been secured by the wagon 
load.” 
Commenting upon the foregoing statements in the Chinch-Bug 
Bulletin, already mentioned, Dr, Thomas remarks: “Although the 
plague among the bugs in this instance appears to have been some- 
what extraordinary, yet it is in accordance with facts ascertained in 
reference to other insects, and as Dr. Shimer is both a competent 
and reliable authority, we accept his statement as correct, and 
believe with him that it was owing as the originating cause to the 
damp season. But we are inclined to believe that the moisture gave 
rise to a minute fungus as the direct cause of the death of the 
chinches. I recollect very distinctly of a similar wholesale destruc- 
tion of house-flies in Southwestern Virginia and East Tennessee in 
1849, by an epidemic. So rapidly was the disease propagated, and 
so great the destruction among the flies, that the utmost caution in 
cooking and drinking water was necessary. Every moist spot was 
covered with the dead and dying. This I am satisfied was caused 
by a fungus. I observed a somewhat similar epidemic prevailing 
- among the grasshoppers in Western Minnesota, Dakota and North- 
ern Iowa, in 1872. All over the plains the dead were seen clasping 
the stems of grass and weeds, and before I was aware of this fact 
more than once I approached cautiously to capture a desired speci- 
men, only to find it dead and rigid. In 1877 the rainy season evi- 
dently caused an immense destruction of the larve of Caloptenus 
spretus.” 
My own paeceatiane upon this interesting subject began on the 
3d of August, 1882, at which time I commenced an examination of 
the fluids of the bodies of specimens of various ages and from vari- 
ous situations, with a view to familiarizing myself with their appear- 
ance in the normal condition of the insect, in order that J might be 
able afterwards readily to detect any departures from that condition 
which circumstances should develop. On the 5th of August, upon 
erushing some chinch-bugs under a cover upon a microscope slide, 
and fdiluting the fluids with freshly distilled water, I found them 
often swarming with minute rod-like bodies, which I took to be 
bacteria, sometimes forming small adherent masses. Careful exam- 
ination under a power of 1,000 diameters showed that these rods 
were usually formed of two, and sometimes four, oval particles, 
joined end to end. Hundreds would often cross the field of view in 
a minute. In order to determine whether these bacteria occurred 
in the circulating fluid or in some other part of the body, I cut off 
the legs and head of a specimen in a small quantity of distilled 
water upon a slide, allowing the blood to escape. The quantity of 
the fluid was, however, highly diluted, and I could find but two 
bacteria. Crushing the remainder of the body of this specimen as 
usual, bacteria were present, but not abundant. On the 7th of 
August I repeated this observation several times, with results 
identical in every particular with those just detailed, except that 
the bacteria were much more abundant in some of the insects than 
in others. Appreciating the possibility of the infection of the fluids 
examined from outside sources, I used every precaution to disinfect 
all the tools and materials with which I worked. ‘The water with 
which the fluids of the chinch-bug were diluted had been freshly 
