December, ’23] 
doane: bees vs. spraying 
529 
The bees were under observation until noon the next day. During 
this time the bees in this check experiment behaved in the same way as 
the bees that were used in the first experiment. All the dead bees that 
could be found were then gathered up and placed in a vial in order that 
they might be submitted to the chemist for analysis, to check the an¬ 
alysis made on the bees taken from the cabinet when it was over the 
tree that had been sprayed. 
When the chemist submitted his report after he had analyzed these 
bees, it was found that the dead bees that were collected in the cabinet at 
the end of the first experiment, contained .00000255 grams of arsenic 
per bee. The bees that were collected while they were still alive during 
the first experiment, showed .000002 grams per bee. The bees that 
were found dead in the cabinet when it was used for the check, con¬ 
tained .0000006 grams of arsenic per bee. 
In making these tests the bees were counted and weighed and then 
placed in beakers and digested with nitric acid followed by sulphuric 
acid. The arsenic was then determined by the well known Gutzeit 
method, a blank on the chemicals was run with the samples. 
These analyses showed that the difference between the content of 
arsenic in the bees that were exposed to the arsenic and those that were 
not exposed, was so minute as to be inconsiderable. 
It must be remembered that all plant and animal substances contain 
quantities of arsenic, so that careful analysis made at any time will 
always show a trace. 
In the spring of 1920 I began another series of experiments in which I 
sprayed the trees while they were in full bloom in order that I might 
test the effect of such a spraying on bees and thus check up the experi¬ 
ments conducted in 1919. On April 12, 1920, two apple trees were 
sprayed with arsenate of lead, using 6 lbs. of arsenate of lead to 50 
gals, of water. About 5 gallons of the spray was applied to each tree 
and care was taken to drive the spray into the calyx cups as much as 
possible. As there was a little mildew on these trees some atomic sul¬ 
phur was used in the spray. Many of the blossoms on one of the trees 
were gone; the other tree had at least half of the blossoms on it and a 
number of bees were visiting the blossoms evidently feeding. In 
another part of the yard a pear tree, which was in full bloom, was 
sprayed with the same material. As this was a small tree all of the 
blossoms were easily available and it was given a good thorough spray¬ 
ing. 
On an adjoining lot was a hive of bees, situated about 25 ft. from the 
