26 FUMIGATION OF APPLES FOR SAN JOSE SCALE. 
In examining the fruit, apples were selected from the top, middle, 
and bottom of the barrel, as usual. It will be noted that all scales 
were killed, except in case of Nos. 68 and 69. After fumigation of 
Nos. 68 to 70 it was found that one of the quarter packages of cyanid 
in which the total dose had been divided had failed to drop into the 
acid jar beneath, so that the quantity of cyanid used was in reality 
at rate of 0.225 gram per cubic foot, instead of 0.30 gram as indi- 
cated in the table. In No. 68, four scales were found on fruit from 
the center of the barrel which were considered doubtful. In No. 69, 
one scale only was doubtful, and this also on an apple found in the 
middle of the barrel. , 
In summarizing the hydrocyanic-acid gas tests during the winter of 
1906-7 it must be said that the results were far from satisfactory. — 
In all cases of fumigation where the apples were more or less loose, 
as in baskets, the scales were invariably all killed, and in the tests 
of the effect of the gas upon the various varieties of apples no injury 
whatever resulted, even though excessive strengths were used— 
much stronger than necessary to destroy the scales. The exception 
of the Rhode Island Greening from western New York, however, is 
to be noted, and as shown in Table VII no strength of gas was found 
which did not injure the fruit. 
In the package series, including the treatment of fruit in boxes 
and barrels as would be necessary in commercial use, there was lack 
of uniformity in killing the scales. As already stated, this was 
probably more apparent than real and resulted from error in classi- 
fication of the insect as to whether dead or alive, as the fruit was 
held under temperature conditions which would perhaps greatly 
‘favor their preservation and natural color. However, in all cases 
where the barrel heads were perforated with auger holes and’ in 
boxes with fruit wrapped or unwrapped all scales were killed. 
TESTS OF CARBON BISULPHID. 
In the preliminary tests of fumigants, one of those tried was 
carbon bisulphid. The first test was made November 14, placing 
scale-infested Baldwin apples in one-third bushel baskets on the 
platform in the fumigating boxes. The carbon bisulphid was 
exposed in shallow dishes placed on top of the fruit. The period 
of exposure was uniformly three hours, the doses, however, varying 
as shown in the table. On account of the poor results secured 
in this test, carbon bisulphid was again tried December 14 (Nos. 
45 to 47, inclusive), the fruit being placed on the floor of the boxes 
and the carbon bisulphid dishes above, so that if possible the fruit 
would be more thoroughly subjected to the fumes, as the liquid 
evaporated and the gas sank to the floor. In this latter, infested 
