101 
1,000,000 specimens. With one-half gallon of oil this breeding piace 
was destroyed, whereupon almost complete relief at the hotel fol- 
lowed. 
In shallow streams several feet wide and half a mile long the hot- 
toms were so densely covered with larvee as to give them the appear- 
ance of a dense covering of moss. Here sufficient black-flies emerged 
daily to make life unbearable for an entire community. It required 
only a few minutes to put dams across the streams to check and 
deepen the water, as a result of which the larvee and pupe died. 
In Mount Washington brook the problem presents a different 
aspect. Damming would be out of the question in most places on 
account of the boulders and the great velocity of the current. Miles 
of such breeding ground can be swept with a stable broom or raked 
with iron rakes in one day. When such larvee are loosened and 
carried to deep water, they will die, but where shallow, noninfested 
water is ahead the operations may simply transfer the breeding 
places. If in such cases a cheese-cloth net is stretched across the 
stream, nearly all larvee can be captured. If a stick pointed at one 
end is fastened to each end of the cloth, it can easily be adjusted to 
streams of any width by winding. 
Through experiments made at Dixville Notch and at Durham, 
N. H., it was found that 5 gallons of oi! poured in at the source of a 
stream averaging 10 feet wide and containing many shallow breed- 
ing places would Jall so many of the larva as to leave only an incon- 
siderable number for a distance of 3! miles, and the water at the 
end of a mile would not be too offensive for cattle to drink. Fish 
apparently escaped down the stream. 
As this species will shift its breeding grounds, it 1s not advisable 
to make permanent dams, but instead cheap water gates may be 
constructed which can be opened and closed at will. 
THE FUMIGATION OF A FRUIT HOUSE FOR CONTROLLING TEE 
CODLING MOTH. 
By A. F.. Burgess, Columbus, Ohio. 
Many larve of the second brood of the coding moth (Carpocapsa 
pomonella Linn.) do not emerge from the fruit until after it is 
picked and placed in storage; hence it 15 usually possible to find 
cocoons 1n the fruit boxes or in crevices in the fruit house during the 
spring. Last April an examination of the boxes in which apples 
were stored in a fruit house at Delaware, Ohio, disclosed the fact that 
many larve were present within their cocoons, and, as the building 
was well constructed, an excellent opportunity was offered for test- 
ing the effect of hydrocyanic-acid gas on this insect. After remov- 
ing the fruit the empty boxes were wllowed to remain in the house 
