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the fumes of burning sulphur or Pyrethrum powder, and the latter, if 
dusted upon them, produces the same stupefying effect that it does 
upon other Diptera. The firm in whose behalf these investigations 
were undertaken informs me that in order to exclude the fly they 
screened all windows and doors with a 24 to the inch wire mesh. They 
also, early in the spring, thoroughly whitewashed and fumigated smoke- 
houses and storerooms, using an admixture of carbolic acid, in the 
whitewash, thus effectually sealing up or killing all hibernating indi- 
viduals that might be lurking in these places. I have not been able 
to recommend any repellant chemical that could be safely incorporated 
with the wash used on the outside of the wrappers. Mr. D also 
informs me that sulphur fumes in the storerooms give a streaked and 
unattractive look to the wash, and the use of this repellant is therefore 
impracticable. 
Smoked beef also suffers to some extent from the attacks of this 
insect, but, as Mr. D says, "not nearly so badly as pork. If a beef 
ham were hanging beside that of a hog, the former would most likely 
be O. K. while the latter would be stung." 
In my correspondence with cheese manufacturers I learn that the loss 
of their products is now far less than it formerly was. 
One of our leading cream-cheese makers writes : 
We are always somewhat troubled with the cheese flies in summer. To keep them 
out of our storerooms we cover the windows with light domestic, as they will go 
through the ordinary wire screen, hut as there will always he more or less of them 
in the rooms, we have the brown fly paper in water always on hand, which keeps 
them pretty well in check. They are worst during the hot season. We do not use 
any chemicals as they would be likely to injure the quality of the cheese. The flies 
deposit their eggs on the outside of the cheese, and in thirty to thirty-six hours they 
begin to squirm and work their way inside, so we usually go through the rooms 
twice a day and look for eggs. They are easily found on the smooth surface, but if 
the bandage is wrinkled or cracked we sometimes miss them. We have not had over 
$5 worth destroyed in two years, and are turning out 800 cheeses per day. 
Another large manufacturer informs me that he 
depends mainly upon fine screens to keep out the fly, and also darkens his store- 
rooms; has each cheese rubbed hard each morning; uses no chemicals, but a cheese 
grease that contains some rosin, which gives a hard coating. Loss not more than 
1 per cent., some seasons not over one-fourth of 1 per cent. 
These reports are encouraging as showing with what comparative 
ease the insect may be kept in check when once its habits are thoroughly 
understood. It is hoped that these few, and not in all particulars 
conclusive, notes may prove of some assistance in popularizing that 
knowledge. 
Mr. Aldrich spoke of an English custom of placing cheese under the 
tap of a beer keg so that the drip would encourage the development 
of the insect. He had been informed that the maggots improved the 
quality of the cheese. 
