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half gallons of water. The arsenic solution was made by boiling 
one ounce of arsenic in one quart of water, and adding this solu¬ 
tion to twenty gallons of cold water. The method of procedure 
was precisely as last year, the trees being thoroughly sprayed with 
a hand force-pump, and with the Deflector Spray and Solid Jet- 
Hose Nozzle manufactured by the Lowell Faucet Company, Low¬ 
ell, Massachusetts. The fluids were thrown in a fine mist-like spray, 
applied until the leaves began to drip. 
The character of the season was the precise opposite of that of 
the year preceding. Then a scant crop followed an abundaxit one; 
now an extraordinarily abundant crop followed a very scanty one. 
The ratio of insects to the apples exposed to their attacks must 
have been, consequently, doubly diminished as compared with that 
of 1885. Further, our experiments were last year limited to 
early apples, no late fruit being available; while this year only 
fall and winter varieties were used. In these, finally, an addi¬ 
tional brood of the codling moth probably developed, making 
three in all for the season; while last year we certainly had but 
two up to the time of harvesting our experimental fruit. 
After spraying, the apples which fell, both from the poisoned 
trees and the untreated checks, were regularly picked up at inter¬ 
vals of about two w T eeks, until October 4. These lots were each 
examined for codling-moth injuries, as were also the pickec. apples 
gathered from the trees October 4. The entire number of apples 
examined from all the trees was 38,688. 
From the data thus recorded tables were prepared, such as I 
published in my last year’s report; and upon these tables the 
present discussion is based. As this years experiments aie really 
continuous with those of the year preceding, I have brought my 
last year’s results into this discussion, pieferring to present the 
whole subject in a complete and finished form, even at the expense 
of some slight repetition of matter already published. 
I have made principal use of the figures in the column maiked 
“Corrected”—a matter requiring a somewhat elaborate explanation. 
Latios are comparable, of course, only w T hen reckoned on the 
same base. For the check trees,, the ratios of damage to the taken 
apples were calculated on the total number fallen, and toi t ie 
picked apples the basis of the reckoning was the number remain¬ 
ing on the trees at the end of the season. Since the treatment 
of the experimental trees kept from falling a certain number ot 
the apples which would otherwise have fallen, it is evident tliaW 
ratios computed on the fallen and picked apples from these tree 
are not comparable, without correction, with. those obtained tion 
the checks. The number of fallen apples being relatively smaller 
the ratios of injury calculated on that number will be too large 
. while with the picked apples the case will be reversed. 1 he ratios 
were consequently corrected throughout by the application or or 
mulas printed in our Bulletin 1, but which it is not necessary t< 
repeat here. / 
