======================================================
| Number | Per cent
| | of total
-----------------------------------+--------+---------
Dipodomys panamintinus mohavensis | 36 | 59.0
Dipodomys merriami merriami | 15 | 24.6
Onychomys torridus pulcher | 4 | 6.6
Peromyscus maniculatus gambeli | 6 | 9.8
-----------------------------------+--------+---------
Populations of _Dipodomys merriami_ and _D. panamintinus_ fluctuate
widely, possibly in response to weather cycles. In November of 1948
trapping in the Joshua belt showed that _panamintinus_ outnumbered
_merriami_ approximately three to one, whereas in December of 1951,
after a succession of unusually dry years, _merriami_ was the more
numerous. Further, _merriami_ occurred in the lower parts of the juniper
belt in 1951 where in 1948 it seemed to be absent.
_Dipodomys merriami merriami_ and _Onychomys torridus pulcher_ are
diagnostic of the Joshua tree woodland association in the San Gabriel
Mountains area, since few individuals of either species occur outside of
this association.