72 THE ARGENTINE ANT. 
insects" (family Cercopidae) were also present in the same nest, 
attached to straws of grass. These were apparently protected from 
the ants by the wet, sticky secretion which surrounded them. This 
is the only instance, however, in which the presence of these insects 
has been recorded in the colonies. 
Sowbugs (Oniscid?e) apparently go among the Argentine ants with 
impunity. These little crustaceans are often found in the ant 
nest, especially if they are located under boards or boxes in moist 
places. There does not appear to be any relationship existing, and 
the ants are apparently indifferent to their presence. 
With the exception of two species of mites, which are true inquilines 
in the ant colonies, the Argentine ant does not pay much attention 
to the majority of mites and spiders. Mention is made on a later 
page of certain spiders which prey upon the ants to a limited extent. 
The cattle tick (Margaropus annulatus Say) nourishes with undi- 
minished vigor in the ant-infested region, and the same may be said 
of the "red mite" of the orange and the red spider of ornamental 
plants (TetranycJius bimaculatus Harv.). 
INQUILINES. 
Only two true inquilines, both mites, have thus far been found in 
the colonies of the Argentine ant. These were first discovered at 
Baton Rouge by the senior author in 1908, and were subsequently 
found in various localities and in nests of various kinds, usually in 
those located in masses of decaying vegetation or litter* Soon after 
they were first found specimens were sent to Dr. L. O. Howard, who 
submitted them to Mr. Nathan Banks, of the Bureau of Entomology. 
Mr. Banks found them to be new, and his descriptions of them were 
published in the Journal of Economic Entomology, volume 1, pages 
263 and 264 (1908), together with notes on their habits, by the senior 
author. 
NATURAL CONTROL. 
As compared with most injurious insects which reach great abun- 
dance the Argentine ant is remarkably free from natural enemies, 
and very few of these have been noted during the course of our inves- 
tigations, while even these few are of little importance. Xo true 
parasites of this ant have been observed, and apparently the only 
enemies are predatory ones. 
NATURAL ENEMIES. 
INSECTS AND SPIDERS. 
In 1909 Mr. Harper Dean observed a small cockroach capturing 
Argentine ant workers in a room in Baton Rouge, La. This insect 
from time to time caught up and ate workers which were traveling 
