is_, No. 783 UU; from Moab, 4,500 ft.,
Grand Co., Utah.

11. _E. ruficaudus ruficaudus_, No. 33884; from 1 mi. W and 2 mi. S
Summit, 5,000 ft., Flathead Co., Montana.

12. _E. ruficaudus simulans_, No. 41478; from 13 mi. E and 5 mi. N
Coeur d'Alene, Kootenai Co., Idaho.

13. _E. cinereicollis cinereicollis_, No. 208621 BS; from Mount
Thomas, White Mountains, Apache Co., Arizona.

14. _E. quadrimaculatus_, No. 95780 BS; from Mountains near Quincy,
Plumas Co., California.

15. _E. speciosus sequoiensis_, No. 29135/41203 BS; from Mount
Whitney, Tulare Co., California.

16. _E. panamintinus panamintinus_, No. 12502 CN; from Coal Kilns,
Panamint Mountains, Inyo Co., California.

17. _E. umbrinus umbrinus_, No. 38062; from Paradise Park, 21 mi. W
and 15 mi. N Vernal, 10,050 ft., Uintah Co., Utah.

18. _E. umbrinus montanus_, No. 20105; from 1/2 mi. E and 3 mi. S
Ward, 9,400 ft., Boulder Co., Colorado. Dorsal view.

19. _E. bulleri bulleri_, No. 193142 NM; from Sierra del Valparaiso,
Zacatecas.]

DISCUSSION

In California, Johnson (1943) recognized ten species of chipmunks and
assigned these to the five main groups of species which were proposed by
Howell (1929). In characterizing each species, Johnson (_op. cit._) not
only made a careful study of skins and skulls, but also employed many
ecological data.

Study of the bacula of the Californian chipmunks supports Johnson's
(_op. cit._) conclusion that there are ten species, but suggests that
there are three (not five) groups of species in California--as well as
elsewhere within the geographic range of the subgenus _Neotamias_. The
three groups are (see figs. 1-19): 1. _minimus_-group (_E. alpinus_, _E.
minimus_, _E. townsendii_, _E. sonomae_, _E. amoenus_, _E. dorsalis_,
and _E. merriami_); 2. _quadrivittatus_-group (_E. quadrivittatus_, _E.
ruficaudus_, _E. cinereicollis_, and _E. quadrimaculatus_); and 3.
_speciosus_-group (_E. speciosus_, _E. panamintinus_, _E. umbrinus_, _E.
palmeri_, and _E. bulleri_).

_Eutamias panamintinus_, according to Howell (_op. cit._:78) and Johnson
(_op. cit._:83), is a near relative of _E. amoenus_. But, the baculum in
_E. panamintinus_ more closely resembles that in _E. speciosus_ than
that in _E. amoenus_ (compare figs. 5, 15, and 16). Consequently I have
placed _E. panamintinus_ in the _speciosus_-group.

In north-central Colorado, specimen