242 



NORTH AMERICAN FAUNA 



[No. 55 



valleys of eastern Oregon (fig. 54). In the collection of the late 

 Donald Dickey, of Pasadena, Calif., are 2 specimens from Oregon, 

 1 collected by Gabrielson near Beatys Butte in Harney County, and 

 1 by Jewett near Powell Butte, Crook County, in arid, sandy, 

 Sonoran desert country. 



General habits. Like their relatives, the kangaroo rats and pocket 

 mice, these quaint little gnomes are desert dwellers, lovers of sandy 

 or mellow soil among the sagebrush, and able to live where there is 

 little rain and long periods of drought. They are nocturnal bur- 

 rowers, sleeping underground during the day and rarely seen except 

 when taken in traps at night. The little paired tracks of the two 

 hind feet, too large for pocket mice and too small for kangaroo rats, 

 are easily recognized in the dusty trails, but the closed burrows, well 

 hidden under the sagebrush, are not easily found. Like many other 



small animals they will 

 follow a long mark made 

 with the foot in the soft 

 soil and may be caught 

 in traps set delicately 

 across these artificial 

 trails and baited with 

 rolled oats. 



They run in little short 

 hops on the two hind feet, 

 rarely leaving a print of 

 the little hands, which are 

 generally folded on the 

 breast and used mainly 

 for feeding, digging, and 

 all the general purposes 

 of hands rather than feet. 

 Their speed is so great 

 that when frightened they disappear like a flash of light over the 

 sandy soil of their own color. In captivity, if quietly handled, they 

 are gentle and unafraid. They are closely like the kangaroo rats in 

 disposition and habits. 



Near the Narrows, where Preble found them in 1896, the writer 

 camped overnight on July 13, 1927, to collect more specimens. In 

 a sandy sagebrush spot near a point of lava rocks about 2 miles 

 southwest of Narrows tracks of the gnome mouse were found and 

 a line of 66 mousetraps set in the most promising localities. The 

 next morning the traps contained the usual numbers of pocket mice, 

 kangaroo rats, white-footed and grasshopper mice, but only one 

 gnome. Their tracks were around many of the traps, and they 

 had taken the bait from several without being caught, but they 

 seemed not to care much for rolled oats. Their tracks in the early 

 morning before the wind and ants had obliterated most of them were 

 easily followed and generally led from the burrows out into patches 

 of the abundant little desert weed, Mentzelia albicaulis, then well 

 laden with flowers and green and ripe seed capsules on which they 

 were feeding. This plant, only 5 to 7 inches high, was loaded with 

 little capsules, half an inch long and half filled with tiny seeds, 

 that, before they are ripe, are full of clear green watery juice, A 



FIGURE 54. Range of the gnome mouse, Microdipo- 

 dops megacepJialus oregonus, in Oregon. Type lo- 

 cality circled. 



