OF WASHINGTON. 229 
bite of which causes a bad blister, would if prepared in the same way pro- 
duce a by far more terrible poison ; the small gray caterpillars would 
furnish an irritating material, which if brought in contact with the blood 
would torture to death any man ; the fat spiders, several inches long and 
covered with spiny hairs which cause a painful itching on the skin, would 
produce another frightful mixture, the effect of which can only be imagined 
with a shudder. 
" The poison is prepared in the woods. In the depths of the forest the 
native lights his fire and prepares the terrible poison, to which even the 
mighty elephant succumbs. It is forbidden to prepare the poison in the 
vicinity of a village. In the forest the native applies the poison to the 
points of his arrows and covers the same with fresh leaves, so that he can- 
not be poisoned himself, and is then ready for war." 
If we deduct from this account what is due to the probable amount of 
lying on the part of the natives or of Stanley's own men, the following 
facts remain : The natives have arrows provided with a powerful poison; 
secondly, Stanley found in the dwellings of the natives quantities of dried 
ants, and Avas informed by the natives or his men that the bodies of these 
ants, when powdered or cooked in palm oil, furnish this poison. Con- 
ceded the truth of the latter point, I think it is a novel fact that formic 
acid is utilized for poisoning arrows, and for this reason I deemed it worth 
while to quote the above passage. I leave it to the medical members of 
our Society to decide what is the effect of formic acid when brought in 
contact with the human blood, and, further, whether or not the effect of 
the poison is destroyed or altered by the process of preparation as de- 
scribed by Stanley. 
In regard to the other poisonous insects mentioned by Stanley there is 
of course a great deal of exaggeration and imagination in Stanley's account, 
which is no doubt largely due to trying circumstances under which he 
penned his letters. The "small gray caterpillar " belongs evidently to 
the so-called stinging caterpillars, and represent the Lagoas and allied 
genera of the New World. It is a well-known fact that the poisonous 
quality resides in their hair covering, and that it is of a chemical and not of 
a mechanical nature. Some of the. very large South American species of 
Lagoa are justly dreaded by every one, as testified by many travellers, and 
along the Everglades in southern Florida nothing is more feared by the 
Indians than a species of this genus which is said to reside in the pine 
woods. 
The large spider mentioned by Stanley appears to be one of the Thera- 
phosidce. His statement that the hairs of these spiders are poisonous is 
no doubt correct, and is corroborated by reliable authority. G. H. von 
Langsdorf, in his " Bemerkungen auf einer Reise um die Welt," v. i, p. 
63 fas quoted in Germar's Magazin d. Ent., v. i, 1813, pp. 183-184), says : 
" The bite of the Aranea avicularia is neither dangerous nor deadly, but 
is liable to cause severe inflammation. The hairs with which the body is 
everywhere covered are detached upon the slightest touch, and cause upon 
