23 
ages of the alimentary canal in that insect, and observations were 
recorded of the occurrence on the chinch-bug of an Entomoph- 
thora, undoubtedly the frequent cause of its death in the field. 
The subsequent discovery that the chinch-bug bacterium (Bacillus 
insector inn) is normal to that insect, occurring always in the 
intestinal coeca, and that similar bacteria are always to be found 
in the corresponding appendages of a large number of other species 
of the higher families of bugs, finally put a stop to experimental 
work on this supposed bacterial disease of the chinch-bug. The 
subject is not yet worked out, however, and will repay further 
study. 
To the Entomoplithora observed by me in 1882 I added in 1887 
another fungus parasite of the chinch-bug, which has proven 
far more destructive than the former. It is closely allied to the 
genus Botrytis, and would be placed by some botanists under 
that genus now. It is at present known, however, in American 
economic literature as Sporotrichum cjtobuliferum, Speg. 
First found to infest the chinch bug, as above, in 1887, and first 
published in that relation by me in October, 1888, it was first observed 
in Illinois during the late summer and fall of 1888 to cause wide¬ 
spread destruction of that insect in the field. It was first certainly 
conveyed to healthy chinch-bugs in Kansas by Prof. Snow in 
July, 1889, by confining these insects with dead and diseased 
specimen^ and the chinch-bugs thus infected were thereupon 
used there for the propagation in the field of the disease from 
which they had died. 
This fungus ( Sporotrichum ) was first cultivated artificially on agar- 
agar by Prof. Boland Thaxter, of New Haven, in April, 1891, and 
by me on the corn-meal mixture and similar substances in May 
of that year, such cultures being first successfully used here for 
the infection of healthy chinch-bugs in the following month. 
The earliest field experiments with the contagion method for 
the chinch-bug were, however, those made by Prof. Lugger in 
Minnesota in October, 1888, but the agent .of contagion in this 
case was said to be the Entomophthora of the chinch-bug instead 
of Sporotrichum. It is very probable that both forms were present. 
Certainly the Sporotrichum appeared spontaneously among living 
chinch-bugs sent me from Minnesota by Prof. Lugger in October, 
1888.* 
The credit of first testing precisely the effect of varying degrees 
of atmospheric moisture on the growth of Entomophthora, and of 
following step by step the progress of an infection introduced into 
the field, with careful reference to varying weather conditions, is 
due to Mr. F. M. Webster, of Indiana. His experiments were 
made with dead specimens received from Kansas in July and 
August, 1889. The same possible uncertainty exists as to the forms 
of the fungous parasites used in this w r ork as in that of Prof. 
Lugger, mentioned above.f 
* Prof. Rugger informs me that Doth Entomophthora and Sporotrichum were unquestionably 
present in his specimens. [April 3, 1895.] 
t Prof. Webster writes me that the chinch-bug Entomophthora ( E. aphidis) was undoubtedly 
present on these insects, the determination having been made by Prof. J. C. Arthur, Botanist at 
Purdue University, but that it is possible that the Sporotrichum may have been present also. [April 
3,1895.] 
