The Project Gutenberg eBook of Geographic Distribution and Taxonomy of the Chipmunks of Wyoming, by John A. White

Specimens examined.—Total number, 118.

Natrona Co.: 2 mi. W and 7 mi. S Casper, 6,370 ft., 2; 10 mi. S Casper, 7,750 ft., 3; 6 mi. S and 2 mi. W Casper, 5,900 ft., 1.

Converse Co.: 21½ mi. S and 24½ mi. W Douglas, 7,600 ft., 10.

Carbon Co.: Lake Marie, 10,440 ft., 1; 2 mi. S and 1/2 mi. W Medicine Bow Peak, 10,400 ft., 1; 2 mi. S and 2 mi. W Medicine Bow Peak, 10,700 ft., 1; 10 mi. N and 14 mi. E Encampment, 8,000 ft., 2; 8 mi. N and 14 mi. E Encampment, 8,400 ft., 2; 8 mi. N and 16 mi. E Encampment, 8,400 ft., 3; 21½ mi. E and 8 mi. N Encampment, 9,400 ft., 2; 10 mi. E and 6 mi. S Saratoga, 8,800 ft., 1; 8 mi. N and 19½ mi. E Savery, 8,800 ft., 16; 17 mi. E and 7 mi. N Savery, 8,300 ft., 1; 7 mi. N and 19 mi. E Savery, 10,128 ft., 1; 14 mi. E and 6 mi. N Savery, 8,400 ft., 1; 5 mi. N and 5 mi. E Savery, 6,900 ft., 2.

Albany Co.: 27 mi. N and 7½ mi. E Laramie, 6,960 ft., 12; 13 mi. E and 9 mi. N Laramie, 7,700 ft., 2; 8¾ mi. E and 6½ mi. S Laramie, 8,200 ft., 1; 5½ mi. ESE Laramie, 8,500 ft., 1; 8 mi. E and 4 mi. S Laramie, 8,600 ft, 1; 2 mi. SE Pole Mountain, 8,200 ft., 19; 3 mi. S Pole Mountain, 8,100 ft., 2; 1 mi. SSE Pole Mountain, 8,350 ft., 3; 3 mi. ESE Browns Peak, 10,000 ft., 15; 2½ mi. ESE Browns Peak, 10,300 ft., 1.

Laramie Co.: 5 mi. W Horse Creek P.O., 7,200 ft., 2; 3½ mi. W Horse Creek P.O., 7,000 ft., 3; 2 mi. W Horse Creek P.O., 6,600 ft., 1.

Additional records (Howell 1929:51): Natrona Co.: Casper Mountains, 7 mi. S Casper. Carbon Co.: Bridger Peak; Riverside. Albany Co.: Springhill, 12 mi. N Laramie Peak; Eagle Peak; Bear Creek, 3 mi. SW Eagle Peak; Laramie Mountains, 10 mi. E Laramie; Woods [= Woods Landing]; Sherman. Laramie Co.: Bluffs near Pole Creek; 6 mi. W Islay.

Average and Extreme Measurements in Millimeters of Adult Chipmunks that Occur in Wyoming

Diagnosis.—Size medium; over-all tone of upper parts often grayish olive; baculum small or medium, slender; tip of baculum 30 to 38 per cent of length of shaft; skull medium, narrow across zygomata.

Comparisons.—From E. dorsalis utahensis, the only subspecies of this species in Wyoming, E. amoenus luteiventris differs in: Dorsal light and dark stripes distinct; over-all tone of upper parts less grayish (more tawny); tip of baculum less than 38 per cent of length of shaft in adult specimens.

From E. umbrinus fremonti, the only subspecies of this species which occurs in the same area with E. amoenus in Wyoming, E. a. luteiventris differs in: Smaller size; tawny underparts; base of baculum not noticeably widened.

For comparisons with E. minimus see the account of that species.

Tamias quadrivittatus luteiventris J. A. Allen, Bull. Amer. Mus. Nat. Hist., 3:101, June, 1890.

Eutamias amoenus luteiventris, Howell, Jour. Mamm., 3:183, August 4, 1922.

Type.—Male, adult, skull and skin, No. 11991/37996 (NM); from "Chief Mountain Lake" [Waterton Lake], 3½ mi. N United States-Canadian Boundary, Alberta; obtained on August 24, 1874, by Elliot Coues; original No. 4596.

Diagnosis.—General tone of upper parts ochraceous; underparts strongly buffy; tip of baculum in adult specimens, more than 30 per cent and less than 38 per cent of length of shaft.

Description.—Color pattern: Crown Cinnamon mixed with Smoke Gray; upper two facial stripes black; submalar stripe Fuscous or Fuscous Black mixed with Ochraceous-Tawny; anterior margin of ear Ochraceous-Tawny; posterior margin of ear and postauricular patch Light Buff or buffy white; hairs inside posterior part of pinna Ochraceous-Tawny; median dorsal dark stripe black; lateral pair of dorsal dark stripes black and mixed with Tawny, frequently brownish; median pair of dorsal light stripes white tinged with Pale Smoke Gray; lateral pair of dorsal light stripes creamy white; sides Tawny or Ochraceous-Tawny; rump and thighs Dark Smoke Gray strongly mixed with Cinnamon-Buff; dorsal surface of tail Fuscous Black mixed with Clay Color; ventral surface of tail Light Ochraceous-Tawny, with Fuscous Black around margin and Clay Color around outermost edge; antipalmar and antiplantar surfaces of feet Cinnamon or Cinnamon-Buff; underparts Cinnamon-Buff or Light Ochraceous-Buff. Skull: Size medium; moderately narrowed across zygomata. Baculum: Slender; not noticeably broadened at base; tip more than 30 per cent of length of shaft.

Remarks.—Although there are no records of this subspecies from the Wind River Mountains, it probably occurs there.

The niche that this subspecies occupies is similar to that of E. m. consobrinus as shown by the fact that these two subspecies have been taken together at the same places.

Specimens of E. a. luteiventris and E. umbrinus fremonti have been taken together at the same places.

In general, E. m. consobrinus occurs in open country and at the edges of forests, whereas E. u. fremonti occurs in the forest. E. a. luteiventris occurs in the intermediate habitat, that is to say, not far into the forest, and not so far out into the open as E. m. consobrinus.

Specimens examined.—Total number, 83.

Yellowstone Park: Unspecified, 2.

Park Co.: 31½ mi. N and 36 mi. W Cody, 6,900 ft., 6; 29 mi. N and 31 mi. W Cody, 7,200 ft., 1; 28 mi. N and 30 mi. W Cody, 7,200 ft., 1; 16¼ mi. N and 17 mi. W Cody, 5,625 ft., 3; 25 mi. S and 28 mi. W Cody, 6,350 ft., 2.

Teton Co.: Two Ocean Lake, 2 (1 FC); Whetstone Creek, 8 (MM); Emma Matilda Lake, 1 (FC); Pacific Creek Road, 2½ mi. E Moran, 1 (FC); Two Ocean Lake Road, 2 (FC); 2 mi. E Moran, 1 (FC); 2½ mi. E and 1/4 mi. N Moran, 6,230 ft., 8; Pacific Creek, 1 (MM); junction of Two Ocean Lake Road and U.S. Highway 187, 2 (FC); Signal Mountain Road, 1 (FC); Leigh Lake, 9 (MM); Indian Paint Brush Canyon, Teton Park, 1 (MM); Teton National Park, 3; 3 mi. E and 1/4 mi. S Moran, 6,200 ft., 1; 3¾ mi. E and 1 mi. S Moran, 6,200 ft., 8; 2½ mi. N and 3½ mi. E Moran, 7,225 ft., 1; Timbered Island, 6,750 ft., 4 mi. N Moose, 5; Bar BC Ranch, 6,500 ft., 2½ mi. NE Moose, 9; Grand Teton, 9,000 ft., Teton Park, 1 (MM); Upper Arizona Creek, Jackson, 1 (MM).

Lincoln Co.: 3 mi. N and 11 mi. E Alpine, 5,650 ft., 2.

Additional records (Howell 1929:69): Yellowstone Park: Mammoth Hot Springs; Roaring Mountain; Bunsen Peak; Yancey; Apollinaris Spring; Canyon; Yellowstone Lake; Upper Geyser Basin; Old Faithful. Park Co.: Near head of Clarks Fork; Pahaska, N Fork Shoshone River at Grinnell Creek; Valley. Teton Co.: Moran; Teton Mountains; Teton Pass. Lincoln Co.: Afton, Salt River Mountains; head of La Barge Creek, 9,100 ft.; Salt River Mountains, 10 mi. SE Afton. Sublette Co.: Merna; Stanley.

Diagnosis.—Size medium to large; general tone of upper parts Smoke Gray; dorsal stripes indistinct or obsolete; often brightly colored at base of tail; keel of baculum proportionally high, approximately 1⁄3 of length of tip; skull longer than 34.5 mm.

Comparisons.—From E. umbrinus, E. dorsalis differs in: Dorsal stripes faint; skull smaller; base of baculum not noticeably expanded; general tone of upper parts grayer.

For comparisons with E. minimus and E. amoenus see the accounts of those species.

Eutamias dorsalis utahensis Merriam, Proc. Biol. Soc. Washington, 11:210, July 1, 1897.

Type.—Male, adult, skull and skin, No. 186457 (NM); from Ogden, Weber County, Utah; obtained on October 9, 1888, by Vernon Bailey; original No. 289.

Diagnosis.—Size medium; dorsal stripes faint; baculum not noticeably widened at base.

Description.—Color pattern: Crown Pale Smoke Gray mixed with Cinnamon; upper facial stripe Fuscous; other facial stripes Sayal Brown mixed with Fuscous or Fuscous Black; anterior margin of ear Ochraceous-Tawny; posterior margin of ear and postauricular patch grayish white; median dorsal dark stripe Fuscous or black; other dorsal dark stripes black and mixed with gray, sometimes barely discernible; dorsal pair light stripes Smoke Gray; lateral pair of light stripes creamy white; rump and thighs Pale Smoke Gray mixed with Cinnamon; dorsal surface of tail Fuscous Black mixed with Tilleul Buff; underside of tail Cinnamon-Buff or Pinkish Buff, Fuscous Black around margin and Tilleul Buff around outermost edge; antipalmar and antiplantar surfaces of feet Cinnamon-Buff; underparts creamy white; sides Pinkish Cinnamon or Light Pinkish Cinnamon. Skull: Size medium; braincase well inflated; zygomata strong, moderately appressed to cranium. Baculum: Small; keel approximately 1⁄3 of length of tip.

Remarks.—Only a few specimens of this subspecies have ever been taken in Wyoming. Little is known about the habits of this chipmunk, which normally is shy and wary.

Specimens examined.—Total number, 6.

Sweetwater Co.: W side Green River, 1 mi. N Utah border, 6.

Additional records (Howell 1929:134): Sweetwater Co.: Green River, 4 mi. NE Linwood, Utah.

Diagnosis.—Size large; general tone of upper parts dark; base of baculum widened; outermost dorsal dark stripe barely discernible or lacking; skull rarely shorter than 34.0 mm.

Comparisons.—For comparisons with the other species of Eutamias in Wyoming, see the accounts of E. minimus, E. amoenus, and E. dorsalis.

Remarks.—E. umbrinus is the largest of the species of Eutamias occurring in Wyoming. This species usually occurs in the Canadian and Hudsonian life-zones in the mountains of northwestern, southwestern, and south-central Wyoming.

Tamias umbrinus J. A. Allen, Bull. Amer. Mus. Nat. Hist. 3:96, June, 1890.

Eutamias umbrinus, Miller and Rehn, Proc. Boston Soc. Nat. Hist., 30:45, December 27, 1901.

Type.—Male, adult, skull and skin, No. 186463 (NM); from Blacks Fork, about 9,500 ft., Uinta Mountains, Summit County, Utah; obtained on September 19, 1888, by Vernon Bailey; original No. 228.

Diagnosis.—Size medium; over-all tone of upper parts dark and shadowy; skull smallest of this species in Wyoming.

Description.—Color pattern: Crown Pale Smoke Gray; facial stripes Fuscous Black or Snuff-Brown; ears Fuscous Black; posterior margin of ear and postauricular patch grayish white; median dorsal dark stripe black with Sayal Brown along margins; lateral pair of dorsal dark stripes Fuscous Black mixed with Sayal Brown, or entirely Sayal Brown; outermost pair of dorsal dark stripes Sayal Brown mixed with Fuscous Black or lacking; sides Sayal Brown mixed with Cinnamon; rump and thighs Sayal Brown mixed with Smoke Gray; antipalmar and antiplantar surfaces of feet Cinnamon-Buff; underside of tail Ochraceous-Tawny or Sayal Brown, with Fuscous Black around margin and Pinkish Buff around outermost edge; underparts creamy white with dark gray underfur. Skull: Smooth and rounded; braincase inflated; zygomata strong. Baculum: Broadened at base; shaft tapers rapidly to tip.

Comparisons.—From E. u. fremonti, the subspecies from the north in the mountains of northwestern Wyoming, E. u. umbrinus differs in: Over-all tone of upper parts darker; sides lighter; skull smaller. From E. u. montanus, the subspecies from the Medicine Bow Range of south-central Wyoming, E. u. umbrinus differs in: Over-all tone of upper parts darker; sides darker; skull smaller.

Remarks.—This subspecies occurs only in the foothills of the Uinta Mountains in the southern part of Uinta County. These "foothills" are well-timbered and at an altitude of 7,000 feet and higher.

Specimens examined.—Total number, 23.

Uinta Co.: 9 mi. S Robertson, 8,000 ft, 15; 10 mi. S and 1 mi. W Robertson, 8,700 ft., 5; 11½ mi. S and 2 mi. E Robertson, 9,200 ft., 1; 2 mi. E and 12 mi. S Robertson, Ashley Nat. Forest, 1; 13 mi. S and 2 mi. E Robertson, 9,200 ft., 1.

Additional records (Howell 1929:95): Uinta Co.: Henry Fork, 5 mi. W Lone Tree; Lone Tree.

Eutamias umbrinus fremonti White, Univ. Kansas Publ., Mus. Nat. Hist. 5:575, December 1, 1953.

Type.—Male, adult, skull, skin, and baculum, No. 41790 (KU); from 31 mi. N Pinedale, 8,025 ft., Sublette County, Wyoming; obtained on July 8, 1951, by Rollin H. Baker; original No. 1596.

Diagnosis.—Size large; over-all tone of upper parts dark; lower tooth-row longest of this species in Wyoming.

Description.—Color pattern: Crown Cinnamon-Buff mixed with gray; upper facial stripe Sepia; ocular stripe Chaetura-Drab; submalar stripe Fuscous Black mixed with Sayal Brown; ears black; anterior margin of ear Mars Yellow; posterior margin of ear grayish white; hairs inside posterior part of pinna Dresden Brown; postauricular patch Pale Smoke Gray; median dorsal dark stripe black; lateral dorsal dark stripes black mixed with Sayal Brown; outermost dorsal dark stripes Buckhorn Brown mixed with black or sometimes absent; median pair of dorsal light stripes grayish mixed with Buckhorn Brown; outer pair of dorsal light stripes creamy white; sides Buckhorn Brown; rump and thighs Pale Smoke Gray mixed with Saccardo's Umber; dorsal surface of tail black mixed with Buckhorn Brown; ventral surface of tail Sayal Brown, with Fuscous Black around margin and white or Light Buff around outermost edge; antipalmar and antiplantar surfaces of feet Warm Buff; underparts creamy white with dark underfur. Skull: Large; zygomata strong and arched; braincase well inflated. Baculum: Broad at base; shaft tapers sharply to tip.

Comparisons.—From E. u. montanus, the subspecies from the Medicine Bow Range of south-central Wyoming, E. u. fremonti differs in: Over-all tone of upper parts darker; underside of tail darker; feet darker; sides darker.

For comparisons with E. u. umbrinus see the account of that subspecies.

Remarks.—This subspecies normally occurs in the forest as do the other subspecies of E. umbrinus in Wyoming. A single specimen taken at 12 mi. N and 3 mi. W Shoshoni, Fremont County, is the exception which probably indicates that E. umbrinus does occur outside of its normal habitat and that gene-flow exists between the subspecies of this species.

Specimens examined.—Total number, 53.

Yellowstone Park: Unspecified, 2.

Park Co.: Beartooth Lake, 1 (BS); 16¼ mi. N and 17 mi. W Cody, 5,625 ft., 2.

Teton Co.: 1 mi. E and 1/4 mi. N Togwotee Pass, 9,800 ft., 2; Amphitheater Lake, Teton Park, 1 (MM); Flat Creek, 4 (MM); head of Cache Creek, 4 (MM); Jackson, Upper Arizona Creek, 2 (MM); Flat Creek-Granite Creek divide, 6 (MM); Flat Creek Pass, 1 (MM); Flat Creek-Gravel Creek divide, 2 (MM).

Lincoln Co.: La Barge Creek, near source, 9,000 ft., 1 (BS).

Fremont Co.: Togwotee Pass, 12 (FC); 12 mi. N and 3 mi. W Shoshoni, 4,650 ft, 1; Mosquito Park R.S., 9,500 ft., 17½ mi. W and 2½ mi. N Lander, 1; 17 mi. S and 6½ mi. W Lander, 8,450 ft., 3.

Sublette Co.: 31 mi. N Pinedale, 8,025 ft., 1; W side Barbara Lake, 10,300 ft., 8 mi. S and 3 mi. W Fremont Peak, 4; 19 mi. W and 2 mi. S Big Piney, 7,700 ft., 5.

Additional records (Howell 1929:95): Park Co.: Near head of Clark Fork; Whirlwind Peak near Pahaska, N Fork Shoshone River; Valley, Shoshone Mountains; Needle Mountain. Teton Co.: Teton Mountains, S Moose Creek. Lincoln Co.: Salt River Mountains. Sublette Co.: Gros Ventre Range, 12 mi. NW Kendall; Merna; 8 mi. W Stanley; Big Sandy. Fremont Co.: Jackey's Creek, 4 mi. SW Dubois; Bull Lake, Wind River Mountains; Lake Fork, Wind River Mountains; Fremont Peak.

Eutamias umbrinus montanus White, Univ. Kansas Publ. Mus. Nat. Hist. 5:576, December 1, 1953.

Type.—Male, adult, skull, skin, and baculum; 20105 (KU); from 1/2 mi. E and 3 mi. S Ward, 9,400 ft., Boulder County, Colorado; obtained on August 1, 1947, by E. L. Cockrum; original No. 721.

Diagnosis.—Size large; over-all tone of upper parts light; sides light.

Description.—Color pattern: Crown Raw Sienna mixed with gray; upper facial stripe and ocular stripe black mixed with Sepia; submalar stripe Snuff-Brown mixed with black; ear black or Sepia; anterior margin of ear Ochraceous-Tawny; posterior margin of ear and postauricular patch grayish white; hairs inside posterior part of pinna Cinnamon-Buff; median dorsal dark stripe black with Sayal Brown along margins; lateral pair of dorsal dark stripes black mixed with Sayal Brown; outermost pair of dorsal dark stripes Sayal Brown mixed with black or sometimes lacking; median pair of dorsal light stripes Pale Smoke Gray mixed with Clay Color; outer pair of dorsal light stripes creamy white; sides Clay Color; rump and thighs Neutral Gray; dorsal surface of tail black mixed with Cinnamon-Buff; ventral surface of tail Ochraceous-Tawny, with black along margin and Cinnamon-Buff or Ochraceous-Tawny along outermost edge; antipalmar and antiplantar surfaces of feet Cinnamon-Buff; underparts creamy white with dark underfur. Skull: Large; zygomata strong and arched; braincase well inflated. Baculum: Broad at base; shaft tapers sharply to tip.

Comparisons.—For comparisons with E. u. umbrinus and E. u. fremonti, see the accounts of those subspecies.

Remarks.—Although in Wyoming this subspecies is known only from the Medicine Bow Range, one would expect to find it occurring in the Snowy Range and the Laramie Range as well, since there seems to be suitable habitat for this subspecies in those mountain ranges.

Specimens examined.—Total number, 3.

Albany Co.: 8 mi. ESE Browns Peak, 10,000 ft., 2; 3½ mi. S Wood's Landing, 1.

Eutamias minimus in Wyoming is divisible into two size-groups of subspecies; the smaller size-group (E. m. minimus and E. m. consobrinus), which occurs in the western part of the State, is significantly smaller, in measurements of the skull and baculum, than the larger size-group (E. m. pallidas, E. m. confinis, E. m. silvaticus, and E. m. operarius) which occurs in the eastern part of the State.

Although all the six subspecies of E. minimus in Wyoming can be differentiated from one another by color pattern, this species cannot be divided, by means of color pattern, into two groups, comparable in geographic range, to the two size-groups that were established above on the basis of variations in the skull and baculum.

Thus, the subspecies of E. minimus are morphologically differentiated at two distinct levels; one level is based on differences in the skull and baculum, while the other is based on differences in color.

Although there is considerable controversy concerning the glacial chronology in the mountains of western North America (Flint 1947:302-303), it is generally agreed that in Wyoming, in Wisconsinan time (the latest glacial age), glaciers covered a large part of the Yellowstone-Teton-Wind River highlands, the Big Horn Mountains, the southern part of the Laramie Range, the Medicine Bow Range, Sierra Madre Range, and the northern foothills of the Uinta Mountains. With this in mind, a possible explanation of the geographic variation in E. minimus of Wyoming, is here attempted.

In Sangamonian time, E. minimus-like chipmunks occurred over most of the region which is now Wyoming, and were divided into two size-groups, much as E. minimus is today.

When permanent snow fields were formed in Wisconsinan time, these chipmunks were restricted in their ranges, not, of course, occurring on the glaciers.

When the glaciers melted at the end of Wisconsinan time, new habitats were thus "uncovered." The chipmunks which moved into these ice-free areas, then, became adapted to the new habitats. This then accounts for the subspeciation of E. m. consobrinus, E. m. confinis, and E. m. operarius.

The Black Hills were not covered by glaciers. In late Pleistocene time these hills were probably of low relief. Subsequent differential erosion produced relief sufficient to provide a different habitat. The chipmunks that continued to occupy this area adapted themselves in color to the new habitat and became E. m. silvaticus.

	Greatest length of skull	Zygomatic breadth	Cranial breadth	Length of nasals	Total length	Length of tail	Length of lower tooth-row	Condylo-alveolar length of mandible
E. m. minimus, S of Bitter Creek, Sweetwater Co.
Mean(5)	29.9	16.7	14.8	9.0	188	84.6	4.65	5.51
Min.♂	29.0	16.5	14.6	8.6	177	81.0	4.52	15.11
Max.	30.9	17.2	15.0	9.8	197	89.0	4.80	16.21

Mean(6)	30.1	17.2	15.1	8.6	193	85.3	4.69	16.08
Min.♀	29.0	16.8	14.9	7.9	184	80.0	4.53	15.71
Max.	30.8	17.7	15.5	9.4	200	93.0	4.91	16.58
E. m. consobrinus, near Jackson, Teton Co.
Mean(4)	30.1	16.6	14.4	8.6	190	83.0	4.48	15.65
Min.♀	29.6	16.4	14.3	8.5	190	80.0	4.43	15.28
Max.	30.7	16.9	14.6	8.8	192	86.0	4.59	15.99

Mean(6)	30.8	17.1	14.5	9.1	200	88.4	4.60	16.05
Min.♀	30.2	16.9	14.1	8.7	195	85.0	4.43	15.60
Max.	31.3	17.5	15.1	9.5	205	92.0	4.84	16.70
E. m. pallidus, Moorcroft and Rockypoint, Weston Co.
Mean(9)	31.8	18.0	15.3	9.3	193	85.8	4.84	16.74
Min.♂	31.4	17.7	14.9	8.5	185	80.0	4.34	16.23
Max.	32.5	18.7	15.9	9.7	204	91.0	5.02	17.21

Mean(7)	32.2	18.2	15.5	9.6	205	91.0	4.97	17.02
Min.♀	31.4	17.8	15.1	9.1	203	86.0	4.70	16.30
Max.	32.9	18.9	16.0	10.3	214	99.0	5.18	17.39
E. m. confinis, Bighorn Mts., near Tensleep, Washakie Co.
Mean(9)	31.6	17.8	15.4	9.3	205	89.6	4.78	16.71
Min.♂	30.4	17.2	14.9	8.9	194	79.0	4.51	16.18
Max.	33.3	19.0	16.2	9.9	228	113.0	5.09	17.70

Mean(8)	32.4	18.7	15.6	9.6	208	88.8	4.83	17.09
Min.♀	31.7	17.9	15.3	9.2	189	76.0	4.69	16.49
Max.	33.1	19.3	16.1	9.7	226	103.0	4.93	17.73
E. m. silvaticus, 16 mi. N Custer, Pennington Co., S.D.
Mean(19)	32.3	18.2	15.5	9.6	200	86.2	4.85	16.78
Min.♂	31.5	17.4	15.0	9.1	189	76.0	4.63	16.19
Max.	33.4	19.4	16.1	10.2	210	94.0	5.13	17.74

Mean(15)	32.6	18.1	15.7	9.5	208	90.2	4.96	16.90
Min.♀	31.5	17.7	15.0	9.1	189	70.0	4.61	16.26
Max.	33.7	19.2	16.2	10.5	220	105.0	5.29	18.28
E. m. operarius, near Pole Mt., Albany Co.
Mean(9)	31.5	17.6	15.2	9.7	193	85.6	4.78	16.52
Min.♂	30.3	17.0	14.9	8.9	183	77.0	4.58	15.63
Max.	32.4	18.2	15.5	10.6	203	91.0	5.12	17.37

Mean(8)	32.2	18.0	15.4	9.7	203	85.7	4.86	16.50
Min.♀	31.1	17.6	15.0	9.2	194	79.0	4.64	15.44
Max.	33.4	18.5	15.8	10.2	212	92.0	5.11	17.21
E. a. luteiventris, near Moran, Teton Co.
Mean(20)	33.6	18.2	15.5	10.6	212	94.8	5.14	17.27
Min.♂	32.2	17.4	14.9	9.8	198	87.0	4.86	16.42
Max.	35.2	18.7	16.2	12.1	221	108.0	5.37	18.39

Mean(10)	33.8	18.5	15.5	11.1	217	91.7	5.13	17.47
Min.♀	33.4	18.1	15.1	10.5	203	81.0	5.06	16.89
Max.	34.7	19.0	16.0	11.5	225	100.0	5.32	18.33
E. d. utahensis, W side Green River, 1 mi. N Utah border.
Mean(4)	34.7	18.9	16.4	10.8	197	84.5	5.08	17.91
Min.♂	34.7	18.7	16.4	0.5	191	81.0	5.00	17.77
Max.	34.8	19.2	16.4	11.1	203	88.0	5.15	18.06

Mean(2)	36.0	19.5	16.3	11.3	211	88.0	5.25	18.87
Min.♀	35.5	19.4	16.2	11.3	210	86.0	5.22	18.73
Max.	36.6	19.7	16.4	11.4	212	90.0	5.28	19.02
E. u. umbrinus, Mts. S Robertson, Uinta Co.
Mean(11)	34.7	18.9	15.7	10.9	218	96.2	5.13	18.04
Min.♂	34.3	18.3	15.6	10.3	215	81.0	4.79	17.57
Max.	35.2	19.4	16.0	11.7	228	112.0	5.42	18.59

Mean(4)	35.1	19.2	15.9	11.0	224	96.4	5.17	18.46
Min.♀	34.9	19.2	15.7	10.3	204	90.0	5.11	18.31
Max.	35.4	20.0	16.2	11.8	234	100.0	5.22	18.98
E. u. fremonti, Togwotee Pass, Fremont Co.
Mean(8)	35.6	19.3	15.9	11.4	223	99.0	5.34	19.17
Min.♂	35.2	18.9	15.8	11.1	216	95.0	5.22	18.72
Max.	36.5	19.7	16.1	11.8	243	111.0	5.57	19.78

Mean(6)	35.3	19.6	15.9	11.3	229	101.0	5.40	19.02
Min.♀	34.5	19.3	15.7	10.9	223	92.0	5.35	18.37
Max.	36.0	20.0	16.5	12.0	239	110.0	5.44	19.51
E. u. montanus, near Longs Peak, Boulder Co., Colorado.
Mean(5)	35.2	18.8	15.5	10.8	226	96.0	5.20	18.29
Min.♂	34.7	18.4	15.2	10.1	215	93.0	5.03	17.80
Max.	36.8	19.4	16.2	11.5	232	115.0	5.53	19.36

Mean(6)	35.7	19.1	15.6	10.9	226	98.0	5.28	18.67
Min.♀	35.1	18.8	15.1	10.3	215	89.0	5.06	18.09
Max.	36.5	19.5	16.0	11.5	231	105.0	5.58	19.35

1926.	Changes during growth in the skull of the rodent Otospermophilus grammurus beecheyi. Univ. California Publ. Zool., 21:355-404, 43 figs., March 9.
1946.	Mammals of Nevada. Univ. California Press, Berkeley, California, pp. xi + 710, 11 pls., 485 figs., July 1.