576 Destruction of Obnoxious Insects by Fungoid Growths. [| August, 
the subject is a pamphlet by Dr. H. A. Hagen, of Harvard Uni- 
versity, in which he advocates the use of the yeast fungus for the 
purpose in question.) 
A proposition of this kind, emanating from so high an author- 
ity, is worthy of the most careful consideration. 
It seems that the possibility of destroying insects by infesting 
them with fungi from spores artificially sown, attracted the atten- 
tion of Dr. Bail, of Prussia, more than a dozen years ago. His 
experiments, however, were not conducted with reference to the 
point in question, but for the purpose of establishing the identity 
of certain forms of fungi which had been regarded as distinct. 
That Dr. Bail’s conclusions do not follow from his experiments ; 
for instance, that the house-fly fungus (Empusa musce) and the 
yeast fungus (Saccharomyces cerevisie) are merely different devel- 
opments of the same species—is an opinion, I think, that every 
mycologist who has had experience in the growth of microscopic 
fungi will endorse. This, however, does not affect Dr. Hagen’s 
main proposition, inasmuch as the identity of the fungus is of 
small importance so long as it proves fatal to insects and its appli- 
cation is practicable. Propositions of a similar nature to that of 
Dr. Hagen’s have been made by other scientists, notably by M. 
Pasteur some years since, whose investigations upon the silk- 
worm disease led him to suggest to the French Commission du 
Phylloxera, the possibility of destroying the insect which had 
committed such fearful ravages upon the grape-growing industry 
of France, by its inoculation with some microscopic fungus. 
it this country, as long ago as 1874, the same idea was sug- 
sad by Dr. John L. LeConte.2 He recommends that a careful 
writ y of the epidemic diseases of insects be. made, especially 
_ those of a fungoid nature, hoping thereby that some sweeping 
remedy may be found by which man can rid himself of insect 
enemies. 
Charles H. Peck, State botanist of New York: sigue ae the 
same idea in 1876, only, however, applying it to the destruction 
of obnoxious plants. He says, “ On the other hand, those fungi 
“ Destruction of Obnoxious Insects, Phylloxera, Potato Beetle, Cotton-worm, Co 5 
orado Grasshopper and Greenhouse pests, by application of the Yeast Fungus.” 
Zia 1879. 
Proceedings of the American E ee for the Advancement of Science,” 
1874, 
3 Fetes. -nint h Annual Report on the State Museum of Natural History (1876): 
p. 30. 
