24 THE MICROSCOPE. Feb. 
the greatest boon. By distributing in the grain fields, 
bread moistened with a culture ofa certain bacillus a 
fatal infectious disease is caused among the animals. The 
mice which consume the bread die within a short time. 
Their dead bodies are consumed by other mice, and these 
become infected in turn. Thus an epidemic is induced 
by which hosts of field mice are vigorously attacked and 
their numbers greatly reduced. 
Another and important application of bacteriology for 
economic purposes in this country includes the experi- 
ments made for the destruction of the chinch bug, (fig. 1), 
Fig. 1.—Chinch Bug x 40. Blissus leucopteras, 
Fig. 2—Diseased Chinch Bug attacked by the parasitic fungus, 
Sporotrichum globuliferum. 
Fig. 3.—Conical spores of Sporotrichum globuliferum x 470. 
Fig. 4.—Germinating spore x 470. 
Figs. 5 tog inclusive. Conidial spores in various stages of develop- 
ment. ; ; 
by artificial means ; not exactly by the cultivation of bac- 
terial poison, but by cultivating from the spores, a para- 
sitic fungus, (fig 3) which is as rapid in its destruction — 
as any bacterial poison would be. 
The chinch bug may be well known as a minute insect 
