14 HOUSE FLIES. 
A Parisian journal, the Matin, during the winter of 1905-6, estab- 
lished a prize of 10,000 francs for the best essay on the destruction of 
the house fly. The jury of competent scientific men awarded the 
prize to the author of a memoir in which it was proposed to use resid- 
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Fic. 9 —The house centipede (Scutigera forceps). 
Adult naturaisize (Atter Marlatt.) 
uum oil in the destruction of the 
egos andlarveofthe fly. Thisoilis 
to be used in privies and cesspools. 
Two liters per superficial meter of 
the pit is mixed with water, stirred 
with a stick of wood, and then 
thrown into the receptacle. It is 
said to form a covering of oil which 
kills all the larve, preventing the 
entrance of flies into the pit and, at 
the same time, the hatching of eggs. 
It makes a protective covering for 
the excrement, and this is said to 
hasten the development of anerobic 
bacteria as in a true septic pit, 
leading in this way to the rapid 
liquefaction of solid matters and 
rendering them much more unfit 
for the development of other bac- | 
teria. For manure it is recom- 
mended to mix this residuum oil 
with earth, with hme, and with 
phosphates, and to spread it at dif- 
ferent times, in the spring by pref- 
erence, upon the manure of farms 
and stables and so on. 
There seems to be a definite pe- 
riod of perhaps 10 days between the 
issuing of the adult flies and the 
laying of eggs. During this period, 
and especially in the early spring, 
it becomes important to trap as 
many flies as possible. With this 
end in view, Prof. C. F. Hodge, of 
Clark University, Worcester, Mass., 
has devised certain flytraps which 
he attaches to garbage cans and to 
screened stable windows, and which he places in the neighborhood of 
possible fly- breeding places. 
So many cheap flytraps are on the market that it is unnecessary and 
undesirable to specify any particular kind. Many of them are good. 
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