MOUNTAIN ANTS OF NORTH AMERICA. 501 



List and Descriptions of Western Mountain Ants. 



Myrmicinae. 



1. Monomorium minimum Buckley. 



The typical form of this species, which is common in Texas and the 

 Atlantic States at lower elevations and south of New England, has been 

 taken by Prof. C. F. Baker in Ormsby County, Nevada, on the eastern 

 shore of Lake Tahoe. I have found it in Arizona and Colorado and 

 Dr. W. M. Mann collected it in the mountains of Hidalgo, Mexico. 



2. Monomorium minimum subsp. ergatogyna Wheeler. 



Known only from Catalina Island, Cala., where it was taken several 

 years ago by Prof. C. F. Baker. 



3. Monomorium minimum, subsp. compressum Wheeler. 

 Taken by Dr. \N. M. Mann at Guerrero Mill, Hidalgo, Mexico. 



4. Monomorium minimum subsp. cyaneum Wheeler. 



A beautiful metallic blue form from the same locality as the preced- 

 ing. 



5. Solenopsis molesta Say. 



The typical form of this species is abundant throughout the East- 

 ern United States and Southern Ontario. It occurs also, but more 

 sporadically, in the mountains of Colorado and New Mexico at alti- 

 tudes below 8000 ft. 



6. Solenopsis molesta var. validiuscula Emery. 



Originally described from Los Angeles and San Jacinto, California. 

 I have taken it in the Santa Inez Mts. near Santa Barbara in the same 

 state, and Dr. Mann has give me specimens which he collected at 

 Wawawai, Washington. 



7. Solenopsis molesta var. castanea Wheeler. 



A dark color variety originally described from Woodland Park, in 

 the Ute Pass, Colorado (Wheeler). 



8. Myrmecina graminicola Latr. subsp. americana Emery. 



A rather rare ant, occurring in rich, shady woods in the Eastern 

 States and as far west as Texas and the Grand Canyon, Arizona. 



