394 Bulletin American Museum of Natural History. [Vol. XXXIV, 
Yellow; posterodorsal portion of head and posterior half of gaster infuscated; 
some specimens also with the thorax slightly fuscous. Mandibular teeth black. 
Female (deilated). Length 5.5 mm. 
Head as long as broad, subrectangular, with rather convex sides and feebly 
excised posterior border. Eyes convex, nearly as long as the sides of the head. 
Antennal scapes not reaching half way between the posterior border of the eyes and 
the corners of the head. Mandibles with only 3 teeth. Lateral clypeal teeth obso- 
lete. Thorax elongate elliptical, nearly three times as long as broad; epinotum 
rounded and sloping, without distinct base and declivity. Petiole not distinctly 
pedunculate, node high, compressed anteroposteriorly, its anterior slope concave in 
profile and rapidly rising to the rather acute summit, the posterior slope straight 
and abrupt. Postpetiole short, transversely elliptical, but little broader than the 
petiole. 
Surface shining and very sparsely and minutely punctate as in the worker; erect 
hairs more abundant and more yellowish. Color of body rich yellowish testaceous, 
with a broad band across the posterior portion of the first gastric segment and the 
basal portions of the succeeding segments dark brown; mandibles and clypeus red. 
Described from two females and numerous workers taken from two 
nests under stones in Miller Cafion, Huachuca Mts., Arizona, at an altitude 
of about 5500 ft. This species is readily distinguished in the worker phase 
from all the described forms of Solenopsis from the United States, except 
those of the geminata group, by its much larger eyes. There is a slight but 
distinct tendency to polymorphism in the worker adumbrating the condi- 
tion seen in geminata Fabr. and wasmanni Emery. 
ll. Solenopsis aurea amblychila subsp. nov. 
Worker. Differmg from the typical aurea Wheeler in having the two carine 
terminating bluntly behind or at the anterior border of the clypeus and not projecting 
beyond the border as two acute teeth, in having the funicular joints 2-7 distinctly 
longer and in the mescépinotal suture, which, though as deeply impressed as in aurea, 
is more acute, i. e., not so broad at the bottom. The profile outline of the thorax is 
therefore different, the base of the epinotum and the posterior surface of the epinotum 
being more nearly straight in aurea and more rounded in the new subspecies. _ 
Female. Differs from that of aurea in the same clypeal characters as the worker. 
Male. Indistinguishable by any satisfactory characters from the male of aurea. 
Described from many specimens taken from populous colonies nesting 
under large stones in the Huachuca Mts., Arizona (Ramsay Cafion 4800 rt. 
Hunter’s Cafion 5500 ft.; Carr Cafion 6000 ft.; Miller Cafion 5000-5400 
ft.). I have also received a series of workers, males and females, from 
Guadalajara, Mexico, taken by Mr. J. F. McClendon. 
