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of it as a cheese pest. Not doubting that there were other works not 
im my library, in which it was more fully discussed, I applied to Dr. 
Williston, as our leading dipterologist, who very kindly answered: 
I, also, have had occasion to search for the life history of Piophila casei without 
success. I supposed there would be no difficulty in finding a full description of its 
habits, but was surprised to find no, or very meager, references in any literature 
at my command, * * * If you have studied its habits you will do a service by 
publishing them, even though it may happen that they have already been pub- 
lished, which I doubt. 
Dr. Riley, however, informs me that the literature of the insect is 
sufficiently extensive though scattered, and that several European 
writers, and especially H. F. Kessler, have within recent years given 
careful accounts of its development and life history. 
Asit was my desire to bring the matter to the attention of the eco- 
nomic entomologists at the present meeting, I did not have time to 
obtain transcriptions from the authorities to which Dr. Riley refers, 
and so will offer here a popular synopsis of my personal observations, 
in which I am conscious there are some gaps and uncertainties. Those 
desiring a more minute and technical account can consult the works 
named by Dr. Riley. 
My attention was directed to this pest about a year ago by an employé 
of one of the largest packing and curing establishments in the West, 
who wrote: “We wish to know what it is, and especially at what 
period in its life it can best be fought. It entails an enormous loss upon 
all our packing-house companies.” Upon my request specimens of the 
infested meat were kindly sent me, and Mr. D , My correspondent, 
gave me much valuable information concerning its work in the pack- 
ing house. 
The packages of ham and shoulder were received during the month 
of August, 1892, and consequently represented the worst work of the 
insect for the season. Swarms of flies escaped from the boxes as they 
were opened and myriads of “ skippers” and puparia in all stages of 
development were disclosed, clustering around the bony ends, among 
the tendons, and in the softer fat and oil-saturated folds of the canvas 
wrappers. The lean meat was never in any case penetrated, although 
eggs and small skippers were abundant on the surface; nor was the 
solid fat much damaged. The methods of curing these meats had been 
so perfect, that even after an exposure of two or three weeks in an 
open shed to the August heats, upon cutting into the center of a ham 
and the thickest part of shoulder they were found to be perfectly sound 
and sweet. In justice to the “skippers,” too, I must say that their 
work does not induce putrescence or ill odors, and although the spec- 
tacle of a ham swarming, externally, with the various forms of the 
insect is the reverse of appetizing, yet a large part of it is still edible 
and, the outside carefully removed, would be available for potted meats 
and similar preparations. But, of course, in the original shape it is 
absolutely unsalable; hence the loss. ; 
