In grazing districts or in areas devoted to intensive agriculture the death sentence should probably be passed on the banner-tailed kangaroo rat.  It should be recalled, however, that this is the largest and one of the handsomest of all its family, and that it is one of the most characteristic and interesting of all the desert fauna; where extensive grazing or agricultural operations are not undertaken, therefore, we feel that the kangaroo rat should be let alone, unless its presence threatens infestation of valuable agricultural or grazing lands.

SUMMARY.

(1) Kangaroo rats may be separated with ease from all other mammals; the long tail and short and weak fore feet separate them from the pocket gophers; the white hip-stripe distinguishes them from the pocket mice.  The decidedly larger size and the white-tipped tail separate Dipodomys spectabilis spectabilis and D. deserti from D. merriami and D. ordii.  The darker color and vividly contrasted black-and-white tail of spectabilis distinguish it from deserti.

(2) Dipodomys s. spectabilis occurs in the open arid country of portions of the Lower and Upper Sonoran Zones of Arizona, New Mexico, Texas, Sonora, and Chihuahua.  It lives in harder soil than does deserti, and builds more conspicuous mounds.

(3) There is no evidence of intergradation or hybridization between spectabilis and deserti.

(4) Dipodomys s. spectabilis is nocturnal; it is gentle, and does not offer to bite when taken in the hand; is silent for the most part; active; somewhat sociable with its fellows, but fights in defense of its food stores; progresses chiefly by leaping; signals by a drumming or tapping on the ground with its hind feet.

(5) The breeding season of spectabilis begins in January and continues into August.  Whether more than one litter is raised in a single season is unknown.  The number of young in each litter varies from 1 to 3, averaging 2.

(6) Dipodomys s. spectabilis does not hibernate, but provides food stores, mostly seeds, for use during seasons when food would be otherwise unavailable.  Storage in each den varies in quantity from 5 grams (about 1/6 ounce) to 5,750 grams (12.67 pounds).  Materials stored include several important forage plants; for example, various species of Bouteloua and Aristida, with B. rothrockii (crowfoot grama) the most important.  Accessibility and abundance of different plants have much to do with the kinds of storage found.

(7) The dens of spectabilis are the most notable of all kangaroo rat dwelling places.  They range from 6 inches to 4 feet in vertical height, and from 5 to 15 feet in diameter.  Here the kangaroo rat has its home, shelter, and food-storage chambers.  Within the den is found a tortuous network of burrows, with many storage and some nest chambers, the whole arranged so as to be two to four stories high.