1934] Ants of the Snake River Plains 223 
10. Manica mutica Emery 
One colony of this ant was observed beneath a large rock 
along a stream, thirty-five miles south of Twin Falls. It was 
quite small and the occupants, all workers, were sluggish 
and unoffensive. 
11. Myrmica brevinodis Emery 
Three nests of this species, which is rather abundant in 
the Middle West, were beneath rocks in a very moist Agro- 
pyron repens area near Twin Falls. 
12. M. brevinodis sulcinodoides Emery 
Several colonies of this variety were beneath rocks in 
Hordeum jubatum areas along streams at Twin Falls. The 
workers were abundant and very sluggish. Winged forms 
appeared in the nests during early July. 
13. Aphaenogaster uinta Wheeler 
Six large colonies of uinta nested beneath rocks in the 
moist Snake River Canyon, near Twin Falls. Only the work- 
ers were found, all of whch were very timid. 
14. A. subterranea occidentalis Emery 
This variety is rather commonly distributed in moist 
areas, where it builds small nests beneath rocks. Winged 
forms apear in July and August, depending upon the locality. 
15. Stenamma brevicorne var. 
This undetermined variety of brevicorne is of lesser im- 
portance in the Twin Falls area, where it occupies very 
minute nests near streams or in other moist habitats. 
16. Crematog aster lineolata var. (near cerasi Fitch) 
Large colonies of this ant abounded beneath flat rocks 
throughout the semidesert area, being more numerous, how- 
ever, in rather moist places. Each colony contained many 
queens. Winged forms appeared in late June near Twin 
Falls. 
17. Dorymyrmex pyramicus Roger 
Nests of this species were found in limited numbers near 
