longer than the body. Cranium triangular, the occiput forming the 

 base and the point of the nose the apex of the triangle, much flat- 

 tened, auditory and particularly mastoid bullae conspicuously in- 

 flated. 



COLOR. 



General color aboye. bro^ynish buffy. yarying in some specimens 

 to lighter bufi^y tints, grizzled -vrith black; oblique hip stripes white: 

 tail with dark-brown or blackish stripes aboye and below, runnino- 



color pattern and characters are remarkably uniform. Young speci- 

 mens, while exhibiting the color pattern and general color of adults. 

 are consiDicuously less brown, and more grayish. 



There appears to be little yariation in color with season. In the 

 series at hand, most specimens taken during the fall, winter, and 

 spring are yery slightly browner than those of summer, suggesting 

 that the fresh pelage following the fall molt is a little brighter than 

 is the pelage after being worn all winter and into the following 

 summer. But at most the difference is slight. 



OIL GLAND. 



Upon separating the hairs of the middle region of the back about 

 a third of the distance between the ears and the rump, one uncovers 

 a prominent gland, elliptical in outline, with long axis longitudinal 

 and about 9 millimeters in length. The gland presents a roughened 

 and granular appearance, and fewer hairs grow upon it than else- 

 where on the back. The hairs in the yicinity are frequently matted, 

 as if with a secretion. In worn stage of pelage the gland may be 

 visible from above without separating the hairs. Bailey has sug- 

 gested that this functions as an oil gland for dressing the fur, and 

 our observations bear out this view. Kangaroo rats kept in cap- 

 tivity without earth or sand soon come to have a bedraggled ap- 

 pearance, as if the pelage were moist. When supplied with fine, 



