Notes on Ant Behavior 207 
Behavior Notes on Certain Ants 
of St. Louis County, Mo.* 
Phil Rau, Kirkwood, Mo. 
Lasius umbratus mixus var. aphidicola 
(Walsh) [M. R. Smith 
I have observed the behavior of the exodus of this ant on 
two separate occasions, and both times it occured near the rear 
porch of my home at Kirkwood, Mo. Unlike - fe hic species, 
Lasius niger var. neoniger the nests were not a abundant 
about the lawn and during the two years only ae colonies 
were observed 
There was a great difference in the dates when the exodus 
took place; the first year observed on October 13, 1929, and 
the second on July 6, 2. In the first instance a large num- 
ber of ants were seen coming out of the ground near the porch 
post and they continued to stream out all day, at first in very 
great numbers and by noon the boards of the porch were black 
with them. From then on the number gradually print oia a 
until at twilight only a few were coming from the nest. 
ratte fed Rhee stents ’ the an 
At the same spot three years later the same kind of exodus 
was pagel. but at that time it occurred earlier in the season, 
July 6, 1932. These ants were undoubtedly the descendants 
of the ‘colony observed in see This exodus started between 
6:30 and 6:45 a. m. A very large number of winged black 
ants (queens and males) eee | up the post for a dis- 
tance of three feet, and then flying diagonally into the air 
There were several hundred wingless yellowish-brown ants, the 
workers of this species, moving slowly among the crowd of 
*The names of the experts who so — identified the material 
appears in brackets throughout the paper 
