Storage content of Den No. 1 (Fig. 1, above), showing the separate species of plants listed in Table 1. The rod is 1 meter long. The large pile on the left is composed of seed-laden heads of crowfoot grama (_Bouteloua rothrockii_), the large pile on the right consists of heads of six-weeks grama (_Bouteloua aristidoides_), the pile of heads in the center is desert plantain (_Plantago ignota_), and the smallest heap is composed of buckwheat-bush seeds (_Eriogonum polycladon_).] The number of lots of storage (24) studied in detail, extending as it does over a period of three years with seasons of varying growth conditions, is not sufficient to permit the construction of a curve showing increase and decrease in quantity of stored material with growing seasons and intervals between; but the results indicate a very decided increase during the autumn storing season, and continuing large well into the winter, since some outside material can still be obtained until midwinter. From about February to April a decrease may be noted, followed, if the spring growth of annuals be good, by a slight increase; and we can very nearly predict the general character of the increases and decreases by the precipitation and consequent growth conditions. TABLE 2.--_Quantity of storage per den correlated with time of year and growth conditions of preceding season (chiefly from United States Range Reserve near the Santa Rita Mountains, Ariz.)._ ------------+-----------+-----------+----------- | | | Den No. | Date. | Quantity. | Preceding | | | season. | | | ------------+-----------+-----------+----------- | 1918. | _Grams._ | | | | 1 | Feb. 7 | 4,127 | Good. 2 | Mar. 9 | 3,615 | Do. 3 | July 25 | 401 | Poor. 4 | Sept. 20 | 734 | Do. 5 | Sept. 21 | 2,520 | Do. 6 | Oct. 17 | 2,315 | Do. 7 | Dec. 20 | 1,247 | Do. | | | | 1919. | | | | | 8 | Feb. 7 | 1,600 | Do. 9 | Mar. 13 | 370 | Do. 10 | Apr. 7 | 180 | Do.[3] 11 | Apr. 9 | 117 | Good.[3] 12 | May 7 | 298 | Do.[3] 13 | May 11 | 1,590 | Do. 14 | Aug. 8 | 5 | Good. 15 | Sept. 4 | 151 | Do. 16 | Oct. 17 | 313 | Do. 17 | Oct. 18 | 583 | Do. 18 | Oct. 25 | 3,410 | Do. 19 | Nov. 1 | 3,026 | Do. 20 | Dec. 13 | 2,816 | Do. | | | | 1920. | | | | | 21 | Jan. 31 | 1,173 | Do.