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Psyche 
LJune 
woodpeckers, 4 species of trogons, 2 species of puffbirds, 1 species of 
jacamar and 1 species of cotinga (Von Hagen, 1938; Hindwood, 
I 959i Hardy, 1963). Most of these species hollow out a portion of 
the nest, and the termites seal the exposed portions so that there is 
no contact between bird and termite. However, the Rufous Wood- 
pecker, Micropternus brachyurus , which nests in active Crematogaster 
carton nests, feeds upon the ants which run all about the bird’s nest 
and over the young, without apparent harm. 
The Gartered Trogon of central South America nests within wasp 
nests, but eats the adult wasps before hollowing a nest cavity (Hind- 
wood, 1959). 
Among the mammals, the aardvark Orycteropus is predatory upon 
termites and lives within the termitaria (Bequaert, 1921, and Alfred 
E. Emerson, personal communication). The dormouse Claviglis 
has been found nesting with young in a cavity in the side of an 
arboreal termite nest in the Belgian Congo (Chapin, 1939). The 
following description adds to the scant record of mammals which 
inhabit social insect nests. 
During observations of a western mound building ant, Form'icci 
opaciventris Emery in 1962, the author found the meadow vole, 
Microtus montanus nanus (Merriam) living within these mounds 
and both adults and young animals entering and leaving their burrow 
frequently. This report will describe the burrow system and detail 
an attempt to define the relationship between vole and ant. 
The study area is located in western Wyoming, one mile east of 
Jackson Lake, near the townsite of Moran, and at an altitude of 
2065 meters. The ant nests are located on a mesic silver sagebrush, 
Artemisia cana, meadow. The soil is a clay loam with an abundant 
ground cover of herbaceous vegetation. 
The nests of Formica opaciventris are earthen mounds with a light 
covering of thatch. The mounds vary in height to 0.7 meters with 
basal diameters as large as two meters. The ants are “aggressive,” 
and when disturbed bite readily, exuding droplets of formic acid. 
There are approximately 400 mounds at the study site and these 
nests have been under observation since 1957 (Scherba, 1961, 1963, 
1964). 
In the Jackson Hole area Microtus montanus has been captured 
from these habitats: alpine meadow, subalpine meadow, lush grass- 
forb meadow, wet sedge meadow, willow savannah, timothy meadow, 
aspen forest, sage-grass community, and willow-alder streamside com- 
munity. Findley (1951) and Negus and Findley (1959) state that 
“this is one of the most versatile mammals . . . from the standpoint 
of habitat selection.” 
