1930] 
An Unusual Nest of Pogonomyrmex 
61 
AN UNUSUAL NEST OF POGONOMYRMEX 1 
By George S. Tulloch 
During 1919 Professor Harlow Shapley, while collecting 
in the vicinity of Pasadena, California, discovered a nest 
of Pogonomyrmex calif ornicus Buckley in which a large 
number of the worker-like forms possessed vestiges of 
wings. Professor Shapley noted this unusual occurrence of 
workers possessing vestigial wings (1920, 1921) and con- 
sidered them to be pterergates following the term sug- 
gested by Dr. Wheeler (1903). Of 1737 worker-like forms 
taken from this nest during 1919 and 1920, 740 were found 
to possess vestigial anterior wings or the stubs of broken 
fore wings. Four ants were noted which possessed vestiges 
of both fore and hind wings — “a phenomenon not hereto- 
fore recorded, as only anterior wings are represented in 
all other pterergates.” There appeared to be no obvious 
reason why this particular nest should present such an 
anomalous condition as the intermittent war with the 
Argentine ant ( Iridomyrmex humilis Mayr) which has been 
introduced there, was no more severe for these ants than 
those of neighboring colonies of the same species. It was 
noted, however, that this nest had little access to wild 
barley and similar grasses which is a common food of the 
species, yet it was well provisioned with mixed grains from 
a nearby feed store whenever the Argentine ants per- 
mitted the nest to be opened for normal harvesting activi- 
ties. An examination of several thousand individuals from 
fifty colonies within a radius of two miles yielded only 
one pterergate. 
While engaged in a study of the Formicoid thorax, Dr. 
Wheeler suggested that the writer communicate with Pro- 
fessor Shapley and ask permission to examine specimens 
Contribution from the Entomological Laboratory of the Bussey 
Institution, Harvard University, No. 328. 
