FLOWERING SHRUBS 
find soil to nourish the plant the Poison Ivy may be found. 
Of its injurious effects on the human body I can speak from 
experience, having witnessed its baneful influence in many 
instances. Gray describes its noxious qualities as “ poison- 
ous to the touch, even the effluvium in sunshine affecting 
some persons.” 
There are various opinions regarding the way in which 
the virus is communicated, and also in what part of the 
plant it exists, some persons thinking that actual contact is 
necessary, others that it is emitted from the leaves when 
wetted by dews and given out in sunshine; again it is 
asserted by some to be the pollen of the flowers floating in 
the air and resting on the skin which is the cause, while 
others say that the poison is given out in a gaseous vapor 
at dewfall. All these suggestions may have some founda- 
tion. I am inclined to think that the poisonous qualities of 
the plant are given out in the héat of the day, when the 
sun’s rays are most powerful, and float freely in the atmos- 
phere, as there are instances of persons being affected in 
daytime when only passing within some little distance of 
places where the plant abounded, without coming into 
actual contact with it in any way. 
To some persons the Poison Ivy is perfectly harmless. I, 
for one, have gathered it for my herbarium in all stages of 
its growth, without receiving from it the slightest injury, 
while other members of the family have suffered severely 
from having been near it or walking among the shrubs 
where it was growing. It is during the hot summer months 
that most of the cases of poisoning occur, especially in June 
and July. 
The first symptoms are redness about the eyelids, ears, and 
throat, which quickly increase to angry inflamed blotches, 
rising in blisters, the whole face becoming swollen so as to 
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