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driving it from the dusted plants, although bugs confined in a box with 
it would survive several days. 
The little Halticus pallicornis, which was this year very troublesome, 
not only in the clover fields and vegetable gardens, on beans, cucumbers, 
etc., but was especially destructive to asters, was also routed by having 
hig powder puffed on the under side of the earee the young bugs were 
killed and the mature ones driven away. 
The Dust was further tested on a few late ane Agrotis saucia, 
Celena renigera, and some other species which I can not name, but 
without much effect, as the powdered worms in the course of an hour 
all crawled out of the deep box in which they had been confined and 
escaped. 
All hairy larve, as inthe case of Pyrethrum, seemed insensible to its 
effects, so also did the striped and twelve-spotted cucumber beetles and 
other mature Coleoptera and the squash-bug. 
There are quite a number of injurious insects on which I did not have 
opportunity to use it, and on which I hope to experiment with it another 
season. 
From my experience with it this season I should rank it among the 
second-class insecticides, producing similar effects, but not quite equal 
to the California Buhach, but still valuable for use against certain in- 
sects on which it is not safe or expedient to employ the arsenates. 
NOTES ON PHYLLOXERA RILEYI FOR 1889. 
June 15.—Received instructions. through Mr. Howard to coilect and 
prepare specimens of Ph. rileyi in all its stages in fluid and in balsam 
on microscopic slides. 
The post-oaks (Q. obtusiloba), on which the insect chiefly occurs on 
the place, were found to be less abundantly infested than during other 
years. The first leaves which have attained their growth and are begin- 
ning to toughen are, however, considerably speckled with their punct- 
ures, especially along the midrib and principal veins. Very few besides 
the pale yellow, smooth, elongate forms are noticeable. 
Put up a number of infested leaves in alcohol reduced about 60 per 
cent. with water. (These I afterwards learned from Mr. Howard did not 
keep, the alcohol being perhaps too strong). I also prepared slides. 
July 22.—Have just returned from Minnesota. Sent slides on. to 
Washington. Examined leaves of post-oak around home, but found no 
winged Phylloxera, and very little change in the specimens on the leaves 
during the last month. 
Among other insects preying on the aphis is Gcanthus latipennis in 
noticeable numbers, one or more on the under side of nearly every leaf. 
They are now nearly full-grown larve. The puzzle is how they come 
to be on the oaks, when I have never found their punctures in the twigs 
and when some of the trees are at quite a distance from raspberry or 
grape vines, in which they mostly deposit their eggs. 
July 29.—After driving about the country in several directions I 
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