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.
| | |
------------+-----------+-----------+-----------