54 
Poisonous Arthropods 
In the brown-tail district, there are many proprietary remedies of 
which the best ones are essentially the following, as recommended 
by Kirkland (1907): 
Carbolic acid. drachm. 
Zinc oxide. }4 oz. 
Lime water. 8 oz. 
Shake thoroughly and nib well into the affected parts. 
In some cases, and especially where there is danger of secondary 
infection, the use of a weak solution of creoline (one teaspoonful to a 
quart of water), is to be advised. 
Vescicating Insects and those Possessing Other Poisons in 
their Blood Plasma 
We have seen that certain forms, for example, the 
poisonous spiders, not only secrete a toxine in their 
poison glands, but that such a substance may be ex¬ 
tracted from other parts of their body, or even their 
eggs. There are many insects which likewise possess a 
42a. Blister bee- poisonous blood plasma. Such forms have been well 
tie. 
designated by Taschenberg as cryptotoxic (xpuxTO<; = 
hidden). We shall consider a few representative forms. 
The Blister Beetles —Fore¬ 
most among the cryptotoxic 
insects are the Meloidce or 
“blister beetles,” to which the 
well-known “Spanish fly” (fig. 
42a), formerly very generally 
used in medical practice, be¬ 
longs. The vescicating property 
is due to the presence in the 
blood plasma of a peculiar, 
volatile, crystalline substance 
known as cantharidin, which is 
especially abundant in the repro¬ 
ductive organs of the beetle. Ac¬ 
cording to Robert, the amount 
of this varies in different species 
from .4 or .5% to 2.57% of the 
dry weight of the beetle. 
426. An American blister beetle. Meloe an- 
gusticollis. Photograph by M. V. S. 
