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Psyche 
[December 
similar and they occur in the same stations in the southwest. 
As long as it was believed that only pallida occurred in this 
area, there was little reason to suspect the existence of a 
second species. 
The writer first encountered Ps. a'pache in 1932. In Sep- 
tember of that year a single, dealated female was taken in 
Ramsey Canyon in the Huachuca Mountains of Arizona. 
This insect had a clear, yellow color similar to that of Ps . 
pallida , but it differed from the female of pallida in its much 
greater size and in a number of other structural features. 
Since no workers were associated with the above female, 
its status was problematical and it was not included in my 
1950 monograph on North American ants. In the spring 
of 1949, after that paper had gone to press, Dr. L. F. 
Byars sent me a number of workers of a large, yellow 
Pseudomyrmex which had come from three colonies taken 
in southern Arizona. These seemed to be the same species 
as the female from Ramsey Canyon, but this was not veri- 
fied until the following summer. In 1950 a colony contain- 
ing all three castes was taken by the writer in Garden 
Canyon in the Huachuca Mountains. Since that time the 
writer has secured forty-five additional colonies of this 
ant in fifteen different stations. These stations extend from 
the Brownsville area of Texas to the mountains of southern 
California. It is clear that this ant is abundant in the 
southwestern United States and some cognizance must be 
taken of it. The difficulty is to decide how this insect should 
be treated. 
The writer first believed that this ant represented Ps. 
decipiens or a northern race of it. Dr. W. M. Wheeler had 
identified as decipiens a series of specimens taken in Costa 
Rica. These specimens were similar to those coming from 
the southwestern United States but there were several dif- 
ferences, particularly in the shape of the petiole. In 1949, 
when the above comparison was made, there was not enough 
material to evaluate these differences. As a result the writer 
told Dr. Byars that the insect probably represented some 
form of decipiens , but that no certain statement could be 
made until more data was available. In the meantime the 
writer attempted to discover how Dr. Wheeler had identi- 
