March, 1914] WhEELER : AnTS FROM HiDALGO, MeXICO. 51 



Tucson, Arizona (F. Silvestri) ; Bed of Santa Cruz River, Tuc- 

 son (Wheeler) ; Huachuca Mts., Arizona (Wheeler and W. M. 

 Mann). 



Ph. vasUti is certainly much more closely related to the series of 

 forms embracing Ph. texana Wheeler, hyatti Emery, crassicornis, 

 Emery, etc. than to Ph. kingi, rugifrons, etc. This latter group is 

 much more closely related to our typically nearctic series of Pheidoles, 

 including Ph. piUfera Roger, vinclandica Forel, etc. Hence I am 

 unable to follow Forel in including vasliti in the subgenus Allo- 

 phcidolc, merely because it possesses polymorphic, instead of dimor- 

 phic workers. In order to emphasize this conclusion I have placed 

 it in a distinct subgenus. 



19. Stenamma manni new species. 



\\'orker. — Length 2.5-3.5 mm. 



In the shape of the body very much like S. westwoodi Westwood and 

 breviconie Mayr, but the eyes are much larger and the basal joint of the 

 funiculi a little longer and less transverse. Sculpture of the head, thorax and 

 pedicel a little finer and more as in the subsp. diecki Emery of the latter 

 species, so that the surface, especially of the pronotum and posterior portion of 

 the head, is somewhat shining. Pilosity much as in the other species of the 

 genus, but the color is very different, being black, with the tarsi, articulations 

 of the legs, the mandibles and tips of the antenn3e, dark red. 



Female. — Length 4.2 mm. 



Closely resembling the worker, except for the usual sexual differences. 

 \\'ings distinctly infuscated, with the inner branch of the cubital vein arising 

 from the cubital cell a short distance proximal to the cross-vein. The venation 

 is therefore intermediate between that of S. nearcticum Mayr and zvestwoodi 

 on the one hand and brevicorne on the other, since in the two former species 

 the inner branch of the cubital arises at a point just distal to the cross-vein, 

 whereas in the latter it arises from the middle of the cubital cell. The veins 

 and sitgma are, moreover, dark brown in color, but very pale in nearcticum 

 and brevicorne and only slightly darker in westii-oodi. 



Described from two females and 13 workers taken from a couple 

 of colonies, which were nesting under large stones in a damp spot in 

 the pine forest on the trail between Real del Monte and El Chico at 

 the summit of the range (10,000 to 11,000 ft.). 



20. Pogonomyrmex barbatus F. Smith. 



Several workers, three males and a dealated female from Pachuca 

 are referable to this form. The workers measure 5.5—6 mm., and are 



