Part 2

Geographic distribution.--Southeastern Alberta, southeast to eastern Wyoming and adjacent parts of South Dakota and Nebraska.

Diagnosis.--External measurements of the holotype and average and extreme external measurements of six adults (five males and one female) from several localities in eastern Wyoming are, respectively, as follows: Total length, 124, 132 (125-140); length of tail-vertebrae, 53, 63 (59-68); length of hind foot, 16.5, 17 (17-18); length of ear, 6.5, 6.6 (6.0-7.0). Color: Upper parts Cream Buff, lined with black and giving a pale olivaceous appearance; lateral line near (16'd) Light Ochraceous-Buff; postauricular patches Cream Buff; subauricular patches and underparts white; tail indistinctly bicolor, dusky above, whitish below. Skull: Size medium for species (see Table 1); braincase and auditory bullae moderately inflated; interorbital region narrow; mastoidal region broad.

Remarks.--From topotypes of Perognathus fasciatus fasciatus, geographically adjacent to the northeast, P. f. olivaceogriseus differs in: Upper parts paler, especially face which is heavily washed with buff; hind foot smaller; skull averaging slightly smaller in all measurements taken (especially least interorbital breadth and cranial depth), except mastoidal breadth which is slightly more and interparietal breadth, length of tympanic bulla and length of maxillary tooth-row which are approximately the same. From topotypes of Perognathus fasciatus infraluteus, geographically adjacent to the south, P. f. olivaceogriseus differs in: Upper parts paler and less drab; lateral line brighter and more ochraceous; underparts never buffy; skull averaging larger in all measurements taken except interparietal breadth and length of maxillary tooth-row which are smaller. From topotypes of Perognathus fasciatus litus, geographically adjacent to the southwest, P. f. olivaceogriseus differs in: Upper parts darker; skull, when specimens of equal age are compared, averaging larger in mastoidal breadth, interparietal breadth and basal length. From topotypes of Perognathus fasciatus callistus, P. f. olivaceogriseus differs in: Upper parts slightly darker, pelage not silky, coarser in appearance; hind foot shorter; skull averaging smaller in all measurements taken (especially mastoidal breadth), except interparietal breadth which is more.

Swenk (loc. cit.) originally described P. f. olivaceogriseus as a subspecies of Perognathus flavescens. I have examined the holotype, kindly made available to me by Dr. Seth B. Benson of the Museum of Vertebrate Zoology, University of California, and the paratype, in the collection of the University of Nebraska State Museum. Neither is P. flavescens, but both are clearly specimens of P. Fasciatus on the basis of olive-gray dorsal coloration, larger over-all dimensions of the skull, and in that the tympanic bullae do not meet anteriorly. In addition, a third specimen from Glen, Nebraska, purported by Swenk to be intermediate between flavescens and olivaceogriseus, has been examined and found to be an immature fasciatus.

FIGS. 2-4. Perognathus fasciatus fasciatus. Buford, Williams County, North Dakota, May 6, 1910, [** Male], No. 168599 USBS.

FIGS. 5-7. Perognathus flavescens flavescens, Kennedy, Cherry County, Nebraska, July 9, 1935, [** Female], No. 66883 MVZ.]

In the original description Swenk indicated the type locality as Chadron, Dawes County, Nebraska. The locality given on the specimen label of the holotype, however, is 5 mi. E Chadron. In addition, Swenk (loc. cit.), in the paragraph preceding the description of olivaceogriseus, states that the holotype was actually taken on Little Bordeaux Creek, sec. 14, T. 33 N, R. 48 W, 3 mi. E Chadron, on the farm of L. M. Gates, who obtained the holotype. It seems best to restrict the type locality to the place last mentioned.

Four specimens from southeastern Alberta recently reported by Moore (1953:143) have been examined and seem best referred, among known subspecies of fasciatus, to P. f. olivaceogriseus. They differ from the latter in several minor cranial features and more drab back, sides and lateral line. When adequate material is available they may prove to be subspecifically different from olivaceogriseus. Moore referred these specimens to P. f. fasciatus.

Specimens from extreme northwestern Nebraska, including the holotype, are slightly darker than specimens from eastern Wyoming. A specimen from Ft. Steele, Wyoming, shows approach to P. f. litus in pale dorsal coloration.

Specimens examined.--Total number, 59, as follows: ALBERTA: Foremost, 2 (UADZ). Manyberries, 1 (Alberta Dept. Pub. Health). Medicine Hat, 1 (Alberta Dept. Pub. Health). MONTANA: Carter County: Little Missouri River, 8 mi. NE Albion, 1 (USBS). Custer County: Calf Creek, 2 (AMNH); 13 mi. E Miles City, 1 (MZ). Garfield County: Piney Buttes, 1 (USBS). Powder River County: Powderville, 2 (USBS). Yellowstone County: Lake Basin, 1 (USBS). County undesignated: Wolf's Creek, 1 (AMNH). NEBRASKA: Cherry County: 10 mi. E Gordon, 1 (CNHM); 12 mi. ESE Gordon, 2 (CNHM). Dawes County: Chadron State Park, 1 (NGFPC); 1 mi. SW Chadron, 1 (NSM); Little Bordeaux Creek, 3 mi. E Chadron, 1 (MVZ); 10 mi. S Chadron, 3 (MZ); 3 mi. SW Crawford, 1 (KU). Sheridan County: Mirage Township, 1 (MZ). Sioux County: Glen, 1 (NSM); Monroe Canyon, 1 (NGFPC). SOUTH DAKOTA: Custer County: Cheyenne River, 1 (AMNH); Elk Mountain, 4800 ft., 4 (USBS). Meade County: Smithville, 1 (USBS). Shannon County: Corral Draw, 3 (AMNH); Pine Ridge, 3 (CNHM 1, USBS 2). Washabaugh County: White River flood plain, 7 mi. S Kadoka, 1 (MZ). WYOMING: Campbell County: 1-1/4 mi. N, 1/2 mi. E Rockypoint, 3850 ft., 1 (KU). Carbon County: Ft. Steele, 1 (USBS). Fremont County: 40 mi. E Dubois, 1 (MZ). Hot Springs County: Kirby Creek, 5000 ft., 1 (USBS). Johnson County: 6-1/2 mi. W, 2 mi. S Buffalo, 5620 ft., 4 (KU); 1 mi. WSW Kaycee, 4700 ft., 1 (KU). Natrona County: Casper, 1 (USBS); 1 mi. NE Casper, 5150 ft., 1 (KU). Platte County: 2-1/2 mi. S Chugwater, 1 (KU). Sheridan County: Arvada, 2 (USBS); 5 mi. NE Clearmont, 3900 ft., 1 (KU). Weston County: Newcastle, 1 (USBS); 23 mi. SW Newcastle, 4500 ft., 4 (KU).

=Perognathus fasciatus infraluteus= Thomas

Perognathus infraluteus Thomas, Ann. Mag. Nat. Hist., ser. 6, 11:406, May, 1893, type from Loveland, Larimer County, Colorado.

Perognathus fasciatus infraluteus, Osgood, N. Amer. Fauna, 18:19, September 20, 1900.

Geographic distribution.--Known only from the type locality and from 7 mi. N Ramah, Colorado. Probably in other parts of northeastern Colorado (see Figure 1).

Remarks.--For comparisons with Perognathus fasciatus olivaceogriseus Swenk, geographically adjacent to the north, see the preceding account of that subspecies on page 520.

Of the seven topotypes available to me, six show various degrees of encroachment of the color of the lateral line upon the underparts, giving the ventral surface a buffy appearance, the "distinguishing character" of the subspecies according to Osgood (op. cit.:20). When additional specimens are available, this character may be found to be one of individual variation, although no specimens from other parts of the range of the species have been found to exhibit it. Of the subspecies P. f. infraluteus, each of the eight specimens examined by me possesses buffy subauricular patches.

The specimen from 7 mi. N Ramah, Colorado, is slightly darker and less drab than the topotypes and does not possess buffy underparts. The skull of the specimen is broken but on the basis of characters of the pelage it seems to be intermediate between infraluteus and olivaceogriseus and is referred to the former on geographic grounds.

Specimens examined.--Total number, 8, as follows: COLORADO: Elbert County: 7 mi. N Ramah, 1 (MZ). Larimer County: Loveland, 7 (USBS).

=Perognathus fasciatus litus= Cary

Perognathus fasciatus litus Cary, Proc. Biol. Soc. Wash., 24:61, March 22, 1911, type from Sun, Sweetwater Valley, Natrona County, Wyoming.

Geographic distribution.--Lower Sweetwater Valley and adjacent parts of Red Desert in Carbon, Fremont, Natrona and Sweetwater counties, Wyoming (see Figure 1).

Remarks.--For comparisons with Perognathus fasciatus olivaceogriseus, geographically adjacent to the northeast, see account of that subspecies. From Perognathus fasciatus callistus, geographically adjacent to the southwest, P. f. litus differs in: Upper parts paler with no trace of olivaceous; hind foot shorter; skull, when specimens of equal age are compared, averaging smaller in all measurements taken (especially occipitonasal length, mastoidal breadth, length of tympanic bulla and cranial depth), except interparietal breadth which is more.

No fully adult specimens of P. f. litus have been available to me for this study. Two of the three specimens mentioned by Cary in the original description (holotype not seen) have been examined and found to possess adult pelage, but cranially they must be classed as young adults. These specimens are paler than those of any other subspecies of fasciatus and do not have the olivaceous dorsal coloration present in other subspecies.

P. f. litus is seemingly an endemic race in the lower Sweetwater Valley and adjacent parts of the Red Desert, Wyoming. The type locality, recorded by Cary in the original description as "Sun, Sweetwater Valley, Wyoming," is here placed in Natrona County on the basis of the map (frontispiece) in Cary's (1917) "Life Zone Investigations in Wyoming."

Specimens examined.--Total number, 9, as follows: WYOMING: Carbon County: 8 mi. SE Lost Soldier, 6700 ft., 1 (USBS). Fremont County: Granite Mts., 1 (MZ). Natrona County: 5 mi. W Independence Rock, 6000 ft., 4 (KU); Sun, 1 (USBS); 16 mi. S, 11 mi. W Waltman, 6950 ft., 1 (KU). Sweetwater County: 27 mi. N Table Rock, 1 (MZ).

=Perognathus fasciatus callistus= Osgood

Perognathus callistus Osgood, N. Amer. Fauna, 18:28, September 20, 1900, type from Kinney Ranch, near Bitter Creek, Sweetwater County, Wyoming.

Geographic distribution.--East of the Green River in central and southern parts of Sweetwater County, Wyoming, and adjacent parts of Moffat County, Colorado (see Figure 1).