Chapter IV: Part 4

=Nevada=: _Washoe County_: 3 mi. N Vya, 3 (MVZ); 4-1/2 mi. NE
Painted Point, 4 (MVZ); 8-1/2 mi. E Vya, 1 (MVZ); 3 mi. E Painted
Point, 1 (MVZ); Long Valley Ranch, 3 mi. S Vya, 1 (MVZ); 10-1/2
mi. S Vya, 1 (MVZ); 11 mi. S Vya, 2 (MVZ); 13 mi. S Vya, 4 (MVZ);
Hausen, 4800 ft., 8 (MVZ); 10 mi. SE Hausen, 4675 ft., 7 (MVZ);
2-1/2 mi. E and 11 mi. N Gerlach, 4050 ft., 4 (MVZ); Smoke Creek,
9 mi. E California line, 3900 ft., 5 (MVZ); 40° 28' N Lat., 6 mi.
E California line, 4000 ft., 3 (MVZ); Horse Canyon, 3 mi. NW
Pahrum Peak, 5000 ft., 1 (MVZ); Fox Canyon, 6 mi. S Pahrum Peak,
4800 ft., 4 (MVZ); N side Sand Pass, 3950 ft., 2 (MVZ); 4 mi. NW
Flanigan, 4200 ft., 1 (MVZ); 3-1/2 mi. NW Flanigan, 4200 ft., 1
(MVZ); 3-1/2 mi. E Flanigan, 2 (MVZ); 2-3/4 mi. SW Pyramid, 4300
ft., 2 (MVZ). _Humboldt County_: 1 mi. S Denio, Oregon, 4200 ft.,
6 (MVZ); Quinn River Crossing, 4100 ft., 1 (MVZ). _Elko County_:
Mary's River, 22 mi. N Deeth, 3 (MVZ); 1 mi. SE Tuscarora, 5900
ft., 2 (MVZ); 5 mi. W Halleck, 5200 ft., 7 (MVZ); 3 mi. W Halleck,
5300 ft., 2 (MVZ). _Lander County_: 1 mi. E Battle Mountain, 1
(MVZ); Reese River Valley, 6 mi. N Austin, 2 (MVZ); Malloy Ranch,
5 mi. W Austin, 3 (MVZ); 2-1/2 mi. NE Smiths Creek Ranch, 5800
ft., 1 (MVZ); Campbell Creek, 6900 ft., 3 (MVZ); Campbell Creek
Ranch, 5500 ft., 8 (MVZ). _Eureka County_: 5 mi. N Beowawe, 7
(MVZ); 1/2 mi. S Beowawe, 1 (MVZ); Pine Creek, 2 mi. E Palisades,
7 (MVZ); Evans, 4 (MVZ); Winzell, 3 (MVZ); 4 mi. SE Romano,
Diamond Valley, 1 (MVZ); 8 mi. W Eureka, 12 (MVZ). _White Pine
County_: 5 mi. SE Greens Ranch, Steptoe Valley, 1 (MVZ); Cherry
Creek, 6600 ft., 2 (MVZ); 1 mi. E Illipah, 6100 ft., 3 (MVZ);
5-1/2 mi. SE Ely, 6500 ft., 5 (MVZ); Spring Valley, 5900 ft., 4
mi. S Shoshone, 6 (MVZ). _Nye County_: Bells Ranch, Reese River,
6890 ft., 1 (MVZ).

=Dipodomys ordii idoneus= new subspecies

_Type._--Male, adult, no. 90029, Museum of Zoology, University of
Michigan; San Juan, 12 mi. W Lerdo, 3,800 ft., Durango, Mexico;
obtained on March 1, 1946, by F. and F. Hammerstrom.

_Range._--Known only from the type locality.

_Diagnosis._--Size small (see measurements). Color pale, entire
dorsal surface (c) between Light Ochraceous-Buff and
Ochraceous-Buff, purest on sides, flanks and cheeks; upper parts
but slightly washed with black; arietiform markings, lateral parts
of pinnae of ears, plantar surfaces of hind feet, dorsal and
ventral stripes of tail, brownish; medial part of pinnae of ears
flesh-colored. Skull medium in size; rostrum wide and relatively
long; braincase but slightly inflated; least interorbital width
great; interparietal region relatively narrow; upper incisors
strongly recurved; zygomatic arches relatively heavy and slightly
bowed laterally; auditory bullae greatly inflated ventrally,
laterally and posteriorly.

_Comparisons._--From _Dipodomys ordii ordii_, _D. o. idoneus_
differs in: Size smaller; color lighter; skull larger; nasals
longer and somewhat more inflated distally as opposed to straight;
interorbital width greater; breadth across maxillary arches
greater; interparietal region narrower; auditory bullae more
inflated posteriorly, laterally and ventrally and projecting
anteriorly into orbit; extension of nasals anterior to upper
incisors less; zygomatic arches heavier and more bowed laterally;
paroccipital processes smaller; foramen magnum elongate as
opposed to nearly circular.

From _Dipodomys ordii obscurus_, _D. o. idoneus_ differs as
follows: Size smaller; color lighter; skull larger, rostrum wider;
nasals shorter and more expanded distally; interorbital region
wider; width across maxillary arches greater; interparietal region
narrower; auditory bullae more inflated laterally, posteriorly and
ventrally; zygomatic arches shorter, heavier and less bowed
laterally.

From _Dipodomys ordii palmeri_, _D.o. idoneus_ differs in: Size
smaller; color lighter; skull larger; rostrum shorter and wider;
nasals shorter and more expanded distally; interorbital region
wider; auditory bullae more inflated laterally, posteriorly and
ventrally; zygomatic arches heavier.

From _Dipodomys ordii fuscus_, _D. o. idoneus_ differs as follows:
Size smaller; color lighter; skull smaller; rostrum narrower and
shorter; interorbital width greater; braincase more vaulted;
nasals longer; interparietal region generally wider; auditory
bullae less inflated; breadth across maxillary arches greater;
zygomatic arches heavier and more bowed laterally; pterygoid
fossae ovoid as opposed to subcircular; occipital condyles more
anterior to dorsal evagination when viewed ventrally.

_Dipodomys ordii idoneus_ differs from _Dipodomys ordii
attenuatus_ in larger size, generally darker color and larger
skull.

_Remarks._--This subspecies of _Dipodomys ordii_ is paler than either of the subspecies with adjoining geographic ranges. Measurements of the skull, in proportion to external measurements, are larger than in any other subspecies of _Dipodomys ordii_. Cranially, this new subspecies is more closely allied to _Dipodomys ordii fuscus_ but in color appears to be much closer to _Dipodomys ordii attenuatus_ from which it differs markedly in cranial features.

_Specimens examined._--Total, 3, all from Durango, distributed as
follows: San Juan, 12 mi. W Lerdo, 3 (UM).

=Dipodomys ordii priscus= Hoffmeister

_Dipodomys ordii priscus_ Hoffmeister, Proc. Biol. Soc. Washington,
55:167, December 31, 1942.

_Perodipus longipes_, Allen, Bull. Amer. Mus. Nat, Hist., 8:246,
November, 1896 (part--the part from Kinney Ranch, Wyoming).

_Perodipus montanus richardsoni_, Cary, N. Amer. Fauna, 33:141,
August 17, 1911 (part--the part from Lay, Colorado).

_Periodipus_ [_Dipodomys_] _ordii luteolus_, Svihla, Journ. Mamm.;
12:262, August, 1931 (part--the part from Linwood, Utah).

_Type._--Male, no. 89119, Mus. Vert. Zool., Univ. California;
Kinney Ranch, 21 mi. S Bitter Creek, 7100 ft., Sweetwater County,
Wyoming; obtained on September 16, 1939, by Donald T. Tappe,
original no. 766.

_Range._--Southwestern Wyoming, extreme northeastern Utah and
northwestern Colorado; marginal occurrences are: in Wyoming, 7 mi.
N Ft. Washakie and 10 mi. SW Granger; in Colorado, Lay and Snake
River south of Sunny Peak.

_Diagnosis._--Size medium (see measurements). Color light, entire
dorsal surface between (c) Light Ochraceous-Buff and
Ochraceous-Buff, purest on sides, flanks and cheeks; upper parts
slightly suffused with black; arietiform markings, pinnae of ears,
plantar surfaces of hind feet, dorsal and ventral stripes of tail,
grayish to blackish in different individuals. Skull medium in
size; rostrum long and narrow; nasals long; auditory bullae
relatively narrow and skull long, giving appearance of much
narrower skull than is actually the case; zygomata weak; upper
incisors moderately wide at cutting edge.

_Comparisons._--From _Dipodomys ordii uintensis_, _D. o. priscus_
differs as follows: Hind foot longer; color lighter in all
pigmented areas, and skull smaller in all measurements taken.

From _Dipodomys ordii sanrafaeli_, _D. o. priscus_ differs in:
Color decidedly less red in upper parts; ventral stripe of tail
not continuous to end of pencil; nasals longer; auditory bullae
less inflated.

For comparisons with _Dipodomys ordii luteolus_ and _Dipodomys
ordii terrosus_ see accounts of those subspecies.

_Remarks._--The characters of this subspecies are stable throughout most of its geographic range. It is not known to intergrade with adjacent forms. One specimen, a male, available from the Snake River, south of Sunny Peak, Colorado, however, is not typical of _D. o. priscus_, in that it has a wider and deeper rostrum than any other specimen from the entire range. Between _D. o. priscus_ and _D. o. luteolus_, the skull, but not the color, provides diagnostic differences.

The Red Desert of Wyoming is mostly sandy but there are large exposures of rock and gravel. At the type locality of _D. o. priscus_ rockier soil predominates but is interspersed with stabilized sand dunes where the kangaroo rats are abundant. Traps set on the rocky soils, in a continuous line between the dunes, yielded no kangaroo rats.

Kangaroo rats in the area of the Kinney Ranch, Wyoming, apparently form a good source of food for owls, since many bones (jaws and limb elements) were found in owl pellets at the bases of cliffs approximately 5 miles northeast of the ranch buildings.

_Specimens examined._--Total, 72, distributed as follows:

=Wyoming=: _Fremont County_: 7 mi. N Fort Washakie, 1 (USBS); Fort
Washakie, 1 (USBS); Wind River, 1 (USBS). _Sweetwater County_:
Eden, 1 (USBS); 5 mi. E Rock Springs, 1 (UM); 10 mi. SW Granger,
13 (UM); Bitter Creek, 9 (6 AMNH; 3 CNHM); Kinney Ranch, 21 mi. S
Bitter Creek, 18 (MVZ); Shell Creek, 25 mi. S Bitter Creek, 3
(CM); 30 mi. S Bitter Creek, 3 (KU); 33 mi. S Bitter Creek, 8
(KU). _Carbon County_: 20 mi. W Baggs, 2 (USBS).

=Utah=: _Daggett County_: E bank Green River, 4 mi. E Linwood, 4
(CM).

=Colorado=: _Moffat County_: Snake River, south of Sunny Peak, 1
(USBS); 20 mi. NW Sunbeam, 4 (CM); Bear River, Lay, 1 (USBS). _Rio
Blanco County_: W side White River, 1 mi. N Rangely, 1 (CM).

=Dipodomys ordii celeripes= Durrant and Hall

_Dipodomys ordii celeripes_ Durrant and Hall, Mammalia, 3:10,
March, 1939.

_Dipodomys ordii columbianus_, Hall, Univ. California Publ. Zool.,
37:5, April 10, 1931.

_Type._--Male, adult, no. 1956, Museum of Zoology, University of
Utah; Trout Creek, 4600 ft., Juab County, Utah; obtained on May 5,
1937, by Stephen D. Durrant, original no. 1168.

_Range._--Eastern Nevada, western and west-central Utah, east to
eastern Sevier County, Utah; marginal occurrences are: in Nevada,
Tecoma, Cobre and 8 mi. SE Mt. Moriah; in Utah, E side Clear Lake,
U. B. (Yuba) Dam, 10 mi. SW Nephi, and Trout Creek.

_Diagnosis._--Size small (see measurements). Color pale, entire
dorsal surface Pinkish Buff, purest on sides, flanks and cheeks,
with but slight suffusion of black in upper parts; pinnae of ears,
plantar surfaces of hind feet, dorsal and ventral stripes of tail,
brownish. Skull small; rostrum relatively short and wide; nasals
relatively short; lacrimal processes small; braincase but slightly
vaulted; auditory bullae but little inflated; interorbital region
narrow; styloid processes project on ventral surface of auditory
bullae beyond middle of external auditory meatus; zygomatic arches
robust and bowed laterally; pterygoid fossae ovoid.

_Comparisons._--From _Dipodomys ordii marshalli_, _D. o.
celeripes_ differs as follows: Size smaller, hind foot longer,
tail shorter; color lighter; skull smaller; rostrum wider and
shorter; interorbital region narrower; auditory bullae less
inflated; lacrimal processes smaller; palate shorter; pterygoid
fossae larger.

From _Dipodomys ordii cinderensis_, _D. o. celeripes_ differs as
follows: Size smaller, tail shorter; color lighter; rostrum wider
and shorter; nasals shorter; interorbital width less; auditory
bullae less inflated; foramen magnum wider and shorter; pterygoid
fossae more circular.

From _Dipodomys ordii columbianus_, _D. o. celeripes_ differs in:
Size smaller; color lighter; rostrum wider and shorter;
interorbital width less; interparietal region wider; auditory
bullae, generally, less inflated; upper incisors longer and more
robust; pterygoid fossae larger.

For comparisons with _Dipodomys ordii fetosus_, _Dipodomys ordii
pallidus_ and _Dipodomys ordii panguitchensis_ see accounts of
those subspecies.

_Remarks._--It appears that wherever the range of _D. o. celeripes_ meets that of an adjoining race, intergradation occurs freely. Practically all of the Nevadan specimens referable to this subspecies are intergrades with _Dipodomys ordii columbianus_ in size and color. Specimens from west of Delta, Utah, are intermediate in size between _Dipodomys ordii pallidus_ and _D. o. celeripes_ but their cranial characters are more as in _D. o. celeripes_. Intergrades with _Dipodomys ordii utahensis_ are discussed under the account of that subspecies.

The characters differentiating _D. o. celeripes_ from any contiguous subspecies are not present in every specimen even in the type series.

_Specimens examined._-Total, 96, distributed as follows:

=Nevada=: _Elko County_: 13 mi. N Montello, 5000 ft., 2 (MVZ);
1-1/2 mi. N Tecoma, 4900 ft., 6 (MVZ); Tecoma, 4900 ft., 8 (MVZ);
Cobre, 6100 ft., 3 (MVZ); Salt Springs, 4200 ft., 1 (MVZ). _White
Pine County_: 2 mi. W Smith Creek Cave, 6300 ft., Mt. Moriah, 2
(MVZ); Hendry Creek, 8 mi. SE Mt. Moriah, 6200 ft., 1 (MVZ).

=Utah=: _Tooele County_: Clifton Flat, 7 mi. SW Gold Hill, 6149
ft., 4 (UU); Parrish Ranch, 5 mi. N Ibapah, 5175 ft., 1 (UU);
Ibapah, 5000 ft., 23 (UU). _Juab County_: Trout Creek, 4600 ft.,
21 (19 UU; 1 USAC; 1 MVZ); 20 mi. SW Nephi, 2 (UU); U. B. (Yuba)
Dam, Sevier River, 5000 ft., 10 (UU). _Millard County_: 4 mi. S
Gandy, 5000 ft., 1 (MVZ); Smith Creek, 6 mi. S Gandy, 5400 ft., 2
(MVZ); Hendry Creek, 5000 ft., 17 mi. S Gandy, 4 (MVZ); Oak City,
5000 ft., 1 (UU); White Valley, 60 mi. W Delta, 1 (UU); 35 mi. W
Delta, 1 (UU); East side Clear Lake, 4600 ft., 4 (3 UU; 1 USAC); 2
mi. E Clear Lake, 4600 ft., 2 (UU).

=Dipodomys ordii cineraceus= Goldman

_Dipodomys ordii cineraceus_ Goldman, Journ. Mamm., 20:352, August
14, 1939.

_Type._--Male, no. 263890, U. S. Nat. Mus. Biol. Surv. Coll.;
Dolphin Island, Great Salt Lake, 4250 ft., Box Elder County, Utah;
obtained on June 4, 1938, by William H. Marshall, original no. 57.

_Range._--Dolphin Island, Great Salt Lake, Utah.

_Diagnosis._--Size medium (see measurements). Color pale, upper
parts near Pale Pinkish Buff, but lightly washed with black,
purest on sides and flanks; arietiform markings, pinnae of ears,
plantar surfaces of hind feet, dorsal and ventral stripes of tail,
brownish. Skull medium in size; rostrum short; nasals relatively
short; interparietal region relatively wide; auditory bullae but
slightly inflated.

_Comparisons._--From _Dipodomys ordii utahensis_, _D. o.
cineraceus_ differs in: Size smaller; color lighter; nasals
longer; auditory bullae larger; total length of skull greater.

From _Dipodomys ordii marshalli_, _D. o. cineraceus_ differs in:
Size smaller; color darker; skull larger in all measurements
taken.

_Remarks._--The race _D. o. cineraceus_ along with _Dipodomys microps russeolus_ is found on Dolphin Island, Great Salt Lake, Utah. Dolphin Island is connected with the mainland by a bar that could allow animals from the island to disperse onto the mainland. There are no animals from the mainland, however, that are referable to _D. o. cineraceus_ or to _D. m. russeolus_. The animals available from the mainland, at Kelton, although geographically near Dolphin Island, are referable to _D. o. marshalli_ and to _D. m. bonnevillei_. The paucity of material from the mainland, adjacent to Dolphin Island, may be significant. Future trapping in this area is needed before we can be certain that _D. o. cineraceus_ is isolated.

_Specimens examined._--Total, 2, both from Utah, as follows: _Box
Elder County_: Dolphin Island, Great Salt Lake, 4250 ft., 2 (USNM).

=Dipodomys ordii marshalli= Goldman

_Dipodomys ordii marshalli_ Goldman, Proc. Biol. Soc. Washington,
50:223, December 28, 1937.

_Type._--Female, adult, no. 262655, U. S. Nat. Mus. Biol. Surv.
Coll.; Bird Island, Great Salt Lake, 4,300 ft., Tooele County,
Utah; obtained on June 22, 1937, by W. H. Marshall, X-catalog no.
27969.

_Range._--Bird, Carrington, Badger and Stansbury islands, Great
Salt Lake; around western edge of Great Salt Lake north to Kelton,
Box Elder County, Utah; around southern and southeastern edge of
the lake to mouth of the Jordan River; marginal occurrences are:
all in Utah, Kelton, 2 mi. W Grantsville, 14 mi. W Salt Lake City
and Bird Island, Great Salt Lake.

_Diagnosis._--Size medium (see measurements). Color pale, entire
dorsal surface near Pinkish Buff, purest on sides, flanks and
cheeks with but slight suffusion of black on upper parts;
arietiform markings, pinnae of ears, plantar surfaces of hind
feet, and dorsal and ventral stripes of tail, brownish. Skull
medium in size; rostrum narrow and long; pterygoid fossae ovoid;
cutting edge of upper incisors narrow; external auditory meatus
round and small; jugal straight or nearly so.

_Comparisons._--From _Dipodomys ordii pallidus_, _D. o. marshalli_
differs in: Hind foot smaller; color darker, arietiform markings
more distinct; dorsal and ventral stripes of tail more pronounced;
skull smaller; palate shorter and wider; jugals lighter; external
auditory meatus smaller; cutting edge of upper incisors narrower;
nasals shorter and less flared distally.

From _Dipodomys ordii utahensis_, _D. o. marshalli_ differs in:
Size smaller; color lighter; skull smaller, except least
interorbital width and depth of auditory bullae which are greater;
cutting edge of upper incisors narrower; nasals less flared
distally.

For comparison with _Dipodomys ordii celeripes_ see account of
that subspecies.

_Remarks._--This subspecies was described from Bird Island, Great Salt Lake, and was thought by Marshall (1940:153), who collected the specimens, to be restricted to that island. However, specimens taken over a period of years on the nearby mainland, by students from the University of Utah, are referable to this subspecies. Although these animals from the mainland are referable to _D. o. marshalli_, they have some characteristics of _D. o. utahensis_ from the eastern and southern mainland. Four specimens from Kelton, also on the mainland, are not typical of _D. o. marshalli_; nevertheless, more than half of their characters of taxonomic worth are as in _D. o. marshalli_ to which the animals are referred.

Great Salt Lake has not been so effective in isolating the animals living on the islands as heretofore has been thought. After these supposedly isolated kinds of animals from Great Salt Lake were named, some other workers have shown several of the kinds to have extensive ranges on the mainland. Some of the kinds ranging also on the mainland are: _Dipodomys ordii marshalli_, _Dipodomys microps subtenuis_ and _Peromyscus crinitus pergracilis_. Of the animals named from the islands, I suppose that those which require the semiarid habitat found in this area will all be found to have large ranges on the adjacent mainland and that each of the kinds of animals which do not require the above habitat, and which lived in this region during the Pleistocene, will be found to be restricted to the island from which it was named.

_Specimens examined._--Total, 47, all from Utah, distributed as
follows: _Box Elder County_: Kelton, 4300 ft., 7 (5 MVZ; 2 UU).
_Tooele County_: 2 mi. W Grantsville, 1 (CAS); Bird Island, Great
Salt Lake, 4300 ft., 1 (USNM); Carrington Island, Great Salt Lake,
4300 ft., 1 (USNM); Stansbury Island, Great Salt Lake, 4300 ft., 10
(6 UU; 4 USNM). _Salt Lake County_: 18 mi. W Salt Lake City, 4260
ft., 16 (UU); 17 mi. W Salt Lake City, 4320 ft., 7 (UU); 16 mi. W
Salt Lake City, 4300 ft., 3 (UU); 14 mi. W Salt Lake City, 4300
ft., 1 (UU).

=Dipodomys ordii inaquosus= Hall

_Dipodomys ordii inaquosus_ Hall, Proc. Biol. Soc. Washington,
54:58, May 20, 1941.

_Type._--Male, adult, no. 73580, Museum of Vertebrate Zoology,
University of California; 11 mi. E and 1 mi. N Jungo, 4,200 ft.,
Humboldt County, Nevada; obtained on July 26, 1936, by Ward C.
Russell, original no. 5026.

_Range._--Southeastern Humboldt and northern Lander counties,
Nevada; marginal occurrences, all in Nevada, are: 7 mi. N
Winnemucca, 8 mi. E and 1 mi. N Jungo, 15 mi. SW Winnemucca, 23
mi. NW Battle Mountain, Izenhood, and 18 mi. NE Iron Point.

_Diagnosis._--Size medium (see measurements). Color pale, entire
dorsal surface Pinkish Buff, purest on sides and flanks with but
slight suffusion of black on the upper parts; cheeks white;
arietiform marks indistinct, pinnae of ears, plantar surfaces of
hind feet, dorsal and ventral stripes of tail, brownish. Skull
medium in size; rostrum short and wide; nasals relatively long and
expanded distally; braincase but slightly vaulted; interorbital
width narrow; extension of premaxillae posterior to nasals
relatively great; interparietal relatively large; pterygoid fossae
subcircular; foramen magnum ovoid; auditory bullae relatively
greatly expanded ventrally.

_Comparisons._--From _Dipodomys ordii columbianus_, _D. o.
inaquosus_ differs as follows: Size larger; color lighter; skull
larger; nasals longer; rostrum longer and wider; interorbital
region narrower; braincase more vaulted; interparietal larger;
auditory bullae more inflated ventrally; pterygoid fossae
subcircular as opposed to nearly circular; zygomatic arches more
robust.

From _Dipodomys ordii monoensis_, _D. o. inaquosus_ differs in:
Size larger; color lighter; skull larger; nasals longer; rostrum
wider; interorbital width greater; braincase more vaulted;
auditory bullae more inflated laterally, ventrally and
posteriorly; interparietal region narrower; pterygoid fossae
subcircular as opposed to circular; lacrimal processes larger;
foramen magnum ovoid as opposed to circular.

_Remarks._--In pallor _D. o. inaquosus_ closely approaches _Dipodomys ordii celeripes_ from eastern Nevada and western Utah. The two populations are separated, however, by a large area inhabited by the darker _Dipodomys ordii columbianus_. Specimens from 18 mi. NE Iron Point, Nevada, which Hall (1946:413) refers to _D. o. columbianus_, are intergrades in color, size and cranial characters and here are referred to _D. o. inaquosus_ instead of to _D. o. columbianus_. Animals from Toulon are intergrades between _D. o. inaquosus_ and _Dipodomys ordii monoensis_ but are referable to the latter.

_Specimens examined._--Total, 47, all from Nevada, distributed as
follows: _Humboldt County_: 18 mi. NE Iron Point, 4600 ft., 1
(MVZ); 7 mi. N Winnemucca, 4400 ft., 4 (MVZ); 1 mi. N Winnemucca,
4600 ft., 8 (MVZ); 5 mi. NE Golconda, 7 (MVZ); 3 mi. SW Winnemucca,
4500 ft., 1 (MVZ); 4 mi. SW Winnemucca, 4500 ft., 1 (MVZ); 5 mi. SW
Winnemucca, 4600 ft., 2 (MVZ); 8 mi. E and 1 mi. N Jungo, 4200 ft.,
6 (MVZ); 11 mi. E and 1 mi. N Jungo, 4200 ft., 7 (MVZ); 10 mi. SW
Winnemucca, 4500 ft., 1 (MVZ); 23 mi. NW Battle Mountain, 4 (MVZ).
_Pershing County_: 15 mi. SW Winnemucca, 1 (MVZ). _Lander County_:
Izenhood, 2 (MVZ); 3 mi. S Izenhood, 2 (MVZ).

=Dipodomys ordii attenuatus= Bryant

_Dipodomys ordii attenuatus_ Bryant, Occas. Papers, Museum of
Zool., Louisiana State Univ., no. 5:65, November 10, 1939.

_Type._--Male, no. 80429, Museum of Vertebrate Zoology, University
of California; Mouth of Santa Helena Canyon, 2146 ft., Big Bend of
the Rio Grande, Brewster County, Texas; obtained on November 19,
1938, by Adrey E. Borell, original no. 5581.

_Range._--Big Bend region of Brewster County, Texas.

_Diagnosis._--Size small (see measurements). Color light, entire
dorsal surface between Pinkish Buff and Pinkish Cinnamon, purest
on sides and flanks, upper parts but lightly mixed with black;
cheeks and narrow outer margin of ear, pure white; arietiform
markings absent; pinnae of ears, dorsal and ventral stripes of
tail, brownish; plantar surfaces of hind feet, blackish. Skull
small; rostrum long and narrow; nasals short; interparietal longer
than wide; auditory bullae longer than deep.

_Comparisons._--Compared with _Dipodomys ordii ordii_, _D. o.
attenuatus_ differs in: Size smaller; color lighter; skull
smaller; nasals thinner; rostrum narrower; auditory bullae less
inflated.

From _Dipodomys ordii richardsoni_, _D. o. attenuatus_ differs in
smaller size and lighter color. Skull smaller in all respects.

For comparison with _Dipodomys ordii sennetti_ see account of that
subspecies.

9. _D. o. panguitchensis_ 20. _D. o. fetosus_ 28. _D. o. inaquosus_ 10. _D. o. uintensis_ 21. _D. o. utahensis_ 31. _D. o. longipes_ 11. _D. o. sanrafaeli_ 22. _D. o. columbianus_ 32. _D. o. pallidus_ 12. _D. o. fremonti_ 24. _D. o. priscus_ 33. _D. o. nexilis_ 13. _D. o. monoensis_ 25. _D. o. celeripes_ 34. _D. o. cupidineus_ 17. _D. o. chapmani_ 26. _D. o. cineraceus_ 19. _D. o. cinderensis_ 27. _D. o. marshalli_ ]

_Remarks._--This small race of _Dipodomys ordii_ was known formerly only from the type locality. This study has shown it to range northward and slightly westward. At four places, 6, 20, and 47 miles south of Marathon and 10 miles west of San Vicente, Texas, this race can be said to be typical, in that specimens from these places agree with those from the type locality. At two other localities, 5 miles east of Toyahvale and Kent, Texas, animals show an intergrading tendency toward _Dipodomys ordii ordii_. The animals from these latter places are darker colored and are intermediate in size and cranial characters. Since these animals show more resemblance to _D. o. ordii_ in the majority of characters they are referred to that race, rather than to _D. o. attenuatus_.

_Specimens examined._--Total, 14, all from Texas, distributed as
follows: _Brewster County_: 6 mi. S Marathon, 1 (USBS); 20 mi. S
Marathon, 1 (USBS); Cooper's Well, 47 mi. S Marathon, 4 (MVZ); 10
mi. W San Vicente, 1 (UM); Johnson's Ranch, Big Bend Rio Grande, 4
(2 TCWC; 2 UM); mouth Santa Helena Canyon, 3 (1 TCWC; 2 MVZ).

=Dipodomys ordii fuscus= new subspecies

_Type._--Male, adult, no. 93886, U. S. Nat. Mus., Biol. Surv.
Coll.; Juamave, Tamaulipas, Mexico; obtained on June 3, 1898, by E.
W. Nelson and E. A. Goldman, original no. 12437.

_Range._--Nuevo León, extreme northern Zacatecas, Tamaulipas and
northern San Luis Potosí, Mexico; marginal occurrences are:
Coahuila, La Ventura; Tamaulipas, Tula, Juamave and Nuevo Laredo.

_Diagnosis._--Size medium (see measurements). Color dark, entire
dorsal surface (_a_) between Cinnamon-Buff and Clay Color, purest
on sides, flanks and cheeks, upper parts strongly suffused with
black; posterior surfaces and fold of pinnae of ears, white;
arietiform markings, plantar surfaces of hind feet, inside of
pinnae of ears, dorsal and ventral stripes of tail, blackish.
Skull of medium size; nasals relatively short; interorbital width
narrow; auditory bullae relatively as well as actually greatly
inflated posteriorly, laterally and ventrally; braincase vaulted;
zygomatic arches light and straight; pterygoid fossae ovoid;
rostrum short and wide.

_Comparisons._--From _Dipodomys ordii palmeri_, _D. o. fuscus_
differs in: Size larger; color lighter; skull larger; rostrum
shorter and wider; interorbital width less; nasals shorter;
auditory bullae more expanded laterally, posteriorly and
ventrally; interparietal region narrower; pterygoid fossae more
circular; upper incisors wider at cutting edge; zygomatic arches
straight rather than bowed laterally.

From _Dipodomys ordii obscurus_, _D. o. fuscus_ differs as
follows: Size larger; color lighter; skull larger; rostrum wider
and shorter; interorbital region wider; width across maxillary
arches greater; auditory bullae more expanded laterally,
posteriorly and ventrally; zygomatic arches light and straight
instead of heavy and bowed laterally; pterygoid fossae more nearly
circular; braincase more vaulted; foramen magnum smaller.

From _Dipodomys ordii ordii_, _D. o. fuscus_ differs in: Size
larger; color darker; skull larger; rostrum shorter and wider;
nasals short and more flared distally; interorbital width greater;
auditory bullae more inflated posteriorly, laterally and
ventrally; interparietal region narrower; width across maxillary
arches greater; pterygoid fossae larger and more nearly circular;
braincase more vaulted.

From _Dipodomys ordii sennetti_, _D. o. fuscus_ can be
distinguished by larger size, longer tail, darker color, and
cranially by larger auditory bullae, longer nasals, wider
interorbital region and greater width across maxillary arches.

_Remarks._--This dark subspecies of _Dipodomys ordii_ is most closely allied to _Dipodomys ordii palmeri_ from, which it can be distinguished by the characters set forth under comparisons.

It seems that the Rio Grande serves as a barrier to the dispersal southward of kangaroo rats from the north side and vice versa. _D. o. fuscus_ ranges from the type locality to Nuevo Laredo and has not been found on the north side of the river, being replaced there, up-river, by _Dipodomys ordii medius_ and down-river by _Dipodomys ordii sennetti_.

_Specimens examined._--Total, 53, distributed as follows:

=Coahuila=: San Juan Neponuceno, 5 mi. N La Ventura, 4 (MVZ); La
Ventura, 7 (USBS).

=Tamaulipas=: Nuevo Laredo, 2 (USBS); Miquihuana, 14 (4 USBS; 9
MVZ; 1 AMNH); Juamave, 8 (USBS); Tula, 5 (UM); 3 mi. N Lulú, 5
(MVZ): Lulú, 8 (MVZ).

=Dipodomys ordii longipes= (Merriam)

_Dipodops longipes_ Merriam, N. Amer. Fauna, 3:72, September 11,
1890.

_Perodipus ordii_, Allen, Bull. Amer. Mus. Nat. Hist., 5:71, April
28, 1893 (part--the part from Bluff, Utah).

_Cricetodipus longipes_, Trouessart, Catalogus Mammalium, 1:581,
1897.

_Perodipus longipes_, Elliot, Field Columbian Museum, Zool. Ser.,
2:239, 1901.

_Perodipus ordii longipes_, Goldman, Proc. Biol. Soc. Washington,
30:113, May 23, 1917.

_Dipodomys ordii longipes_, Grinnell, Journ. Mamm., 2:96, May 2,
1921.

_Dipodomys ordii cleomophila_ Goldman, Journ. Washington Acad.
Sci., 23:469, October 15, 1933, type from 5 miles northeast of
Winona, Coconino County, Arizona.

_Type._--Male, no. 17703/24639, U. S. Nat. Mus. Dept. Agric. Coll.;
foot of Echo Cliffs, Painted Desert, Arizona; obtained on September
22, 1889, by C. Hart Merriam, original no. 512.

_Range._--Southeastern Utah, northeastern Arizona to immediately
south of the Little Colorado River, northwestern New Mexico and
extreme southwestern Colorado; marginal occurrences are: in
Arizona, 20 mi. NE Lees Ferry, Foot Echo Cliffs in Painted Desert,
5 mi. NE Winona, Winslow and Holbrook; in New Mexico, 10 mi. SW
Quemado, Riley, Laguna, Chama Canyon and Shiprock.

_Diagnosis._--Size large (see measurements). Color dark, entire
dorsal surface between (_16''_) Pinkish Cinnamon and
Cinnamon-Buff, purest on sides and flanks with but slight
suffusion of black on upper parts; cheeks white; arietiform
markings, pinnae of ears, plantar surfaces of hind feet, dorsal
and ventral stripes of tail, brownish. Skull large; rostrum long
and narrow; nasals long and thin; auditory bullae greatly
inflated; styloid processes project on ventral surface of auditory
bullae beyond middle of external auditory meatus.

_Comparisons._--From _Dipodomys ordii chapmani_, _D. o. longipes_
differs as follows: Size larger; color lighter; skull larger in
all measurements taken; auditory bullae much more inflated.

From _Dipodomys ordii cupidineus_, _D. o. longipes_ differs in:
Size larger; color lighter; rostrum longer and narrower; nasals
longer; interorbital width greater; breadth across zygomatic
processes of maxillae greater; auditory bullae more inflated;
zygomatic arches heavier and more bowed laterally.

For comparisons with _Dipodomys ordii medius_ and _Dipodomys ordii
nexilis_ see accounts of those subspecies.

_Remarks._--The large reddish _Dipodomys ordii longipes_ is notably distinct from those subspecies which have adjoining ranges. The subspecies closest, geographically and morphologically, is _Dipodomys ordii nexilis_ with which _D. o. longipes_ intergrades, in size of body and color of pelage, north of the San Juan River, Utah. This intergradation is probably the result of a migration of _D. o. longipes_ around the head waters of, or above the place in, the river where there is constantly flowing water. It is probably impossible for these animals to cross a constantly flowing stream as wide as the San Juan is in its lower reaches. The San Juan River, however, in 1896, and again in 1934, was so low that it ceased to flow below Aneth (Gregory, 1938:6, 19). Consequently, at these times, _Dipodomys_ could have crossed the river from one side to the other, at least above the Goosenecks. Intergradation is noted also with _Dipodomys ordii medius_ at Chama Canyon, New Mexico, where the color is like that of _D. o. medius_, although the cranial characters are as in _D. o. longipes_; specimens from Chama Canyon are referred to the latter. Ten miles southwest of Quemado and at Riley, New Mexico, intergradation with _Dipodomys ordii ordii_ occurs in the shape of the nasals and the intermediate size of the skull. In color and external measurements these animals more closely resemble _D. o. longipes_.

Goldman (1933:469) described _Dipodomys ordii cleomophila_ from 5 miles northeast of Winona, Coconino County, Arizona, and gave as distinctive characters "upper parts distinctly darker, ... black facial markings more distinct; skull slightly different." These comparative statements were made in reference to _Dipodomys ordii longipes_. While it is true that the animals which Goldman examined are darker and show some slight cranial differences, these animals, in my opinion, are not sufficiently distinct to warrant their separation from _D. o. longipes_. In the degree of expansion of the auditory bullae, the width of the rostrum, the length of the nasals and interorbital width, animals from 5 miles northeast of Winona (2 specimens) are within the range of individual variation shown by _D. o. longipes_. The color is darker, being more as in _Dipodomys ordii chapmani_. Specimens examined from 10 miles north of Angell, Springerville, Tanner Tank and Cedar Ranch Wash, Arizona (listed by Goldman as referable to _D. o. cleomophila_), and those from Wupatki Ruins, Arizona, agree with _D. o. longipes_ except that the width across the maxillary arches is greater. This greater width across the maxillary arches and the darker color of animals from Winona and Wupatki Ruins, in my opinion, afford insufficient basis for the recognition of the subspecies _Dipodomys ordii cleomophila_ Goldman which, therefore, is placed as a synonym of _Dipodomys ordii longipes_ (Merriam).

_Specimens examined._--Total, 244, distributed as follows:

=Utah=: _San Juan County_: 1 mi. N Bluff, 3500 ft., 1 (UU); 1/2
mi. N Bluff, 3300 ft., 7 (UU); Bluff, 2 (UU); Johns Canyon, San
Juan River, 5150 ft., 2 (UU).

=Arizona=: _Coconino County_: 20 mi. NE Lees Ferry, 1 (USNM); 2
mi. S Endische, 2 (MVZ); 2 mi. SE Endische Spring, Navajo
Mountain, 1 (MVZ); 1/2 mi. W Navajo Spring, Echo Cliffs, 4 (MVZ);
5 mi. S Navajo Mountain, 2 (MVZ); 7 mi. SE Navajo Mountain, 1
(MVZ); Moa Vae, 10 (MVZ); 2 mi. S Grand Canyon Bridge, 1 (USBS);
Tuba, 4 (1 USBS; 3 AMNH); 12 mi. above mouth of Moencopi Wash, 2
(USBS); 14 mi. NW Cedar Ridge, 1 (USBS); 5 mi. N Cameron, 1 (MVZ);
Painted Desert, 6 mi. NE Cameron, 1 (MVZ); 5 mi. E Little Colorado
River on Tuba road, 2 (MVZ); Cameron, 4200 ft., 17 (8 LACM; 9
MVZ); Wupatki Ruins, 4 (MVZ); Deadmans Flat, 6400 ft., NE San
Francisco Mt., 3 (MVZ); 3 mi. NW Winona, 4 (USBS); 5 mi. NE
Winona, 2 (USBS); 10 mi. N Angell, Walnut Tank, 8 (USBS); Cedar
Ranch Wash, 3 mi. above mouth, 5 (USBS); Tanner Tank, 2 (USBS);
Tanners Crossing, Painted Desert, 1 (USBS). _Navajo County_: Right
fork, Segi-ot-Sosie Canyon, 11 mi. NW Kayenta, 2 (MVZ); Bat Woman
Canyon, 13 mi. W Kayenta, 1 (MVZ); Kayenta, 4 (USBS); Segi Canyon,
12 mi. WSW Kayenta, 1 (MVZ); Segi Canyon, 13 mi. WSW Kayenta, 1
(MVZ); Oraibi, 6000 ft., 9 (4 USBS; 5 MVZ); Walpi, 2 (USBS); Keam
Canyon, 12 (6 USBS; 3 USNM; 3 MVZ); Winslow, 6 (USBS); Zuni Well,
7-1/2 mi. N Adamana, 9 (MVZ); Holbrook, 10 (USBS); Long Canyon, 3
(AMNH); Bubbling Springs, 2 (AMNH). _Apache County_: Dinnehotso,
5000 ft., 3 (MVZ); Lukachukai, 1 (USBS); Chin Lee, 6 (USBS); 9 mi.
SW Chin Lee, 1 (USBS); 7 mi. from mouth, Canyon de Chelly, 1
(USBS); Fort Defiance, 2 (USNM); Ganado, 1 (USBS); Springerville,
2 (USBS); 3 mi. SE Springerville, 5 (USBS); unspecified, 4 (2
USBS; 2 USNM); Trash Tank, Grand Canyon, 2 (USBS).

=New Mexico=: _San Juan County_: Ship Rock, 4 (USBS); Fruitland, 9
(USBS); Blanco, 1 (USBS); Chaco Canyon National Monument, 4 (MVZ).
_Rio Arriba County_: Chama Canyon, 1 (USBS). _McKinley County_: 2
mi. W Mariano Lake, 3 (MVZ); Gallup, 6 (USBS); Wingate, 6 (USBS);
Thoreau, 2 (USBS); Zuni River, 1 (USBS). _Sandoval County_: Juan
Tafoya, 1 (USBS). _Valencia County_: 8 mi. SE Grants, 7 (UM); 9
mi. SSE Grants, 5 (UM); 2-1/2 mi. E El Morro P. O., Zuni Mts., 1
(LACM); Laguna, 1 (USBS); Laguna Indian Reservation, 7 (LACM).
_Catron County_: Cougar Ranch, NE Adams Diggings, 1 (CAS); 10 mi.
SW Quemado, 1 (USBS). _Socorro County_: 1 mi. S Bernardo, 1 (MVZ);
Riley, 1 (USBS).

=Dipodomys ordii pallidus= Durrant and Setzer

_Dipodomys ordii pallidus_ Durrant and Setzer, Bull. Univ. Utah, 35
(no. 26):24, June 30, 1945.

_Type._--Male, adult, no. 3526, Museum of Zoology, University of
Utah; Old Lincoln Highway, 18 mi. SW Orr's Ranch in Skull Valley,
4,400 ft., Tooele County, Utah; obtained on June 6, 1940, by S. D.
Durrant, original no. 1905.

_Range._--Low valleys of west-central Utah in Tooele, Juab and
Millard counties; marginal occurrences are: all in Utah, 18 mi. SW
Orr's Ranch, 7 mi. S Fish Springs, Hinckley and Lynndyl.

_Diagnosis._--Size medium (see measurements). Color light, entire
dorsal surface Light Pinkish Cinnamon, purest on sides and flanks,
with but slight suffusion of black on upper parts; cheeks white;
arietiform markings, pinnae of ears, plantar surfaces of hind feet,
dorsal and ventral stripes of tail, brownish. Skull large; auditory
bullae long, wide and well inflated; external auditory meatus
elongate with a notch on the dorsal border; nasals long and flaring
distally.

_Comparisons._--From _Dipodomys ordii celeripes_, _D. o. pallidus_
differs in: Size larger; color generally darker, although some
specimens are lighter; skull larger; nasals longer and more flared
distally; interorbital width greater; auditory bullae larger;
external auditory meatus larger.

From _Dipodomys ordii fetosus_, _D. o. pallidus_ differs in: Size
larger; color lighter; ventral stripe of tail indistinct as
opposed to pronounced; skull larger; nasals longer and more flared
distally; auditory bullae larger; external auditory meatus larger;
palate shorter and broader.

For comparisons with _Dipodomys ordii marshalli_ and _Dipodomys
ordii utahensis_ see accounts of those subspecies.

_Remarks._--Among named subspecies of _Dipodomys ordii_, _D. o. pallidus_ most closely resembles, morphologically, _D. a. marshalli_, its nearest geographic neighbor to the north and east. Intergradation with _Dipodomys ordii utahensis_ is noted in color and intermediacy of body size of specimens from Clover Creek. The majority of cranial characters, however, show these animals to be referable to _D. o. utahensis_ rather than to _D. o. pallidus_. Specimens taken at Lynndyl and Hinckley show intergradation in size of body, length and configuration of the nasals and the degree of inflation of the auditory bullae between _Dipodomys ordii celeripes_ and _D. o. pallidus_. The majority of characters studied show these latter animals to be referable to _D. o. pallidus_. Specimens from 35 and 60 miles west of Delta, in size of body and shape and inflation of the auditory bullae, are intermediate between _D. o. pallidus_ and _D. o. celeripes_. These specimens are here referred to _D. o. celeripes_.

_Specimens examined._--Total, 34, all from Utah, distributed as
follows: _Tooele County_: Old Lincoln Highway, 18 mi. SW Orr's
Ranch in Skull Valley, 4400 ft., 9 (UU). _Juab County_: Fish
Springs, 4400 ft., 4 (UU); 7 mi. S Fish Springs, 4400 ft., 4 (UU).
_Millard County_: 1 mi. N Lynndyl, 4768 ft., 5 (UU); Lynndyl, 4768
ft., 1 (UU); Hinckley, 4600 ft., 11 (UU).

=Dipodomys ordii nexilis= Goldman

_Dipodomys ordii nexilis_ Goldman, Journ. Washington, Acad. Sci.,
23:470, October 5, 1933.

_Perodipus longipes_, Warren, Mammals of Colorado, p. 77, 1910
(part--the part from Coventry, Colorado).

_Dipodomys ordii longipes_, Moore, Journ. Mamm., 10:260, August,
1929 (part--the part from Monticello, Utah).

_Type._--Male, adult, no. 149938, U. S. Nat. Mus. Biol. Surv.
Coll.; 5 mi. W Naturita, Montrose County, Colorado; obtained on
July 20, 1907, by Merritt Cary, original no. 1068.

_Range._--West-central Colorado, southwest into San Juan County,
Utah, north of the San Juan River; northwest into Grand County,
Utah, to the Colorado River; and westward probably as far as the
Colorado River; marginal occurrences are: in Utah, Cisco, 18 mi. NE
Moab, and Blanding; in Colorado, 5 mi. W Naturita, and Coventry.

_Diagnosis._--Size medium (see measurements). Color dark, entire
dorsal surface between (_a_) Cinnamon-Buff and Clay Color, purest
on sides and flanks, upper parts strongly suffused with black;
arietiform markings, pinnae of ears, plantar surfaces of hind
feet, dorsal and ventral tail-stripes blackish. Lateral white
stripes of tail less than one fourth of diameter of tail. Skull
large; rostrum long and narrow; nasals long; auditory bullae
strongly inflated; braincase not inflated; pterygoid fossae ovoid.

_Comparisons._--From _Dipodomys ordii sanrafaeli_, _D. o. nexilis_
differs in: Color darker; skull smaller in all measurements taken;
auditory bullae noticeably smaller; width across zygomatic
processes of maxillae less.

From _Dipodomys ordii longipes_, _D. o. nexilis_ differs in: Size
smaller; color darker in all respects; rostrum wider; breadth
across auditory bullae less; interorbital width greater; breadth
across zygomatic processes of maxillae less; cutting edge of upper
incisors wider; zygomatic arch lighter and more nearly straight.

Comparison with _Dipodomys ordii evexus_ is made in account of
that subspecies.

_Remarks._--This animal is apparently not abundant at any place in its range. Two different attempts, by me, to obtain topotypes were unsuccessful. A single specimen was obtained and that was only a skull saved from a mutilated animal that was taken away from a rattlesnake. The habitat at the type locality is such that a person would not expect it to be inhabited by kangaroo rats. The soil is a heavy clay with a generous admixture of stones but in isolated spots there are light sandy soils which should be suitable for kangaroo rats. Even so, 500 traps set in the area of the type locality over a period of two nights yielded no _Dipodomys_.

This subspecies of _Dipodomys ordii_, inhabiting west-central Colorado and southeastern Utah, is darker than any other subspecies with which its range comes in contact. The races to both the north and south are larger, with the exception of the hind foot which is longer in _D. o. nexilis_ than in either _D. o. sanrafaeli_ or _D. o. longipes_. The affinities of _D. o. nexilis_ are with _D. o. longipes_ rather than with any of the other known subspecies of _Dipodomys ordii_.

Intergradation between _D. o. nexilis_ and _D. o. longipes_ is shown by animals from Bluff, San Juan County, Utah, which, however, are referable to the latter. In animals from sixteen miles northwest of Moab, Grand County, Utah, there is intergradation in size of skull and in color between _D. o. nexilis_ and _D. o. sanrafaeli_. The specimens are referred to _D. o. sanrafaeli_.

_D. o. nexilis_ is apparently prevented from extending its range to the northward by the presence there of _D. o. sanrafaeli_. To the south _D. o. nexilis_ encounters _D. o. longipes_ and the San Juan River. To the east it is limited by the Rocky Mountains and to the west by the deep canyons of the Colorado River.

Warren (1942:183) did not apply the name _D. o. nexilis_ to Ord kangaroo rats in Colorado. He listed specimens from Montrose, Montezuma and Mesa counties as being referable to _D. o. longipes_. The specimens from Montezuma County, Colorado, probably are _D. o. longipes_ and those from Montrose and Mesa counties (for which Warren gives no precise localities) are _D. o. nexilis_.

_Specimens examined._--Total, 35, distributed as follows:

=Utah=: _Grand County_: Cisco, 4 (CM); 18 mi. NE Moab, 6000 ft., 1
(UU). _San Juan County_: 15 mi. N Monticello, 4 (MVZ); Blanding, 1
(UU).

=Colorado=: _Delta County_: Hotchkiss, 1 (USBS). _Montrose
County_: Paradox, 1 (DRD); Bedrock, 4 (AMNH); 5 mi. W Naturita, 2
(USBS); Coventry, 3 (1 USBS; 2 AMNH).

=Dipodomys ordii cupidineus= Goldman

_Dipodomys ordii cupidineus_ Goldman, Journ. Washington Acad. Sci.,
14:372, September 19, 1924.

_Type._--Male, no. 243093, U. S. Nat. Mus. Biol. Surv. Coll.; Kanab
Wash, at southern boundary of Kaibab Indian Reservation, Arizona;
obtained on October 12, 1922, by E. A. Goldman, original no. 23384.

_Range._--Northeastern Arizona and south-central Utah; marginal
occurrences are: in Utah, Escalante, near Paria and S of Virgin;
in Arizona, 6 mi. N Wolf Hole, 20 mi. S Wolf Hole, 5 mi. S
Trumbull Spring and 10 mi. S Jacobs Pools in Houserock Valley.

_Diagnosis._--Size large (see measurements). Color relatively
dark, entire dorsal surface between (_16''_) Pinkish Cinnamon and
Cinnamon-Buff, purest on sides and flanks, upper parts washed with
black; arietiform markings, pinnae of ears, dorsal and ventral
stripes of tail, plantar surfaces of hind feet, blackish. Skull
large; auditory bullae well inflated; interorbital width
relatively narrow; rostrum long and narrow; nasals long and
slightly flared distally; pterygoid fossae ovoid; external
auditory meatus small and ovoid; jugal light and relatively
straight.

_Comparisons._--From _Dipodomys ordii chapmani_, _D. o.
cupidineus_ differs in: Size larger; color lighter in all
pigmented areas; skull larger; rostrum shorter and wider; nasals
shorter; auditory bullae more inflated, particularly median
tympanic portion; least interorbital width less.

From _Dipodomys ordii nexilis_, _D. o. cupidineus_ differs as
follows: Size smaller; color lighter in all pigmented areas; skull
smaller; rostrum relatively longer and narrower; least
interorbital width less; auditory bullae less inflated; breadth
across maxillary arches less; foramen magnum circular as opposed
to ovoid; cutting edge of upper incisors narrower; zygomatic
arches lighter.

For comparisons with _Dipodomys ordii cinderensis_, _Dipodomys
ordii panguitchensis_ and _Dipodomys ordii longipes_ see accounts
of those subspecies.

_Remarks._-This subspecies is prevented from intergrading, to the east, with _D. o. longipes_ by the deep canyons of the Colorado River, with _D. o. cinderensis_ by the Virgin River and with _D. o. panguitchensis_ by a series of high mountain ranges. Intergradation does, however, occur with _D. o. sanrafaeli_ in animals from Escalante, Garfield County, Utah, but they are referable to _D. o. cupidineus_. The Colorado River, farther to the north, again serves as a barrier in preventing intergradation between _D. o. nexilis_ and _D. o. cupidineus_.

_Specimens examined._--Total, 122, distributed as follows:

=Utah=: _Garfield County_: Mouth of Calf Creek, Escalante River, 3
(BYU); Ten Mile Spring, 3 (BYU); Escalante, 3 (BYU). _Washington
County_: near Short Creek road, south of town of Virgin, 18 (RH).
_Kane County_: near Paria, 1 (UU); Willow Tank Springs, 7 (BYU); 8
mi. NW Kanab, 4800 ft., 1 (UU); near Sand Dunes, 7 (RH); Kanab, 15
(12 MVZ; 2 BYU; 1 UU); 1 mi. S Kanab, 4400 ft., 2 (UU).

=Arizona=: _Mohave County_: near S Boundary Kaibab Indian
Reservation, 4 (MVZ); 6 mi. N Wolf Hole, 8 (MVZ); 4 mi. N Wolf
Hole; 3 mi. NW Diamond Butte, 7 (USBS); 20 mi. S Wolf Hole, 1
(USBS); 1 mi. W Diamond Butte, 1 (USBS); 6 mi. N Mt. Trumbull, 1
(USBS); Nixon Springs, 6250 ft., W Base Mt. Trumbull, 6 (3 USBS; 3
MVZ); 5 mi. S Trumbull Spring, 1 (USBS). _Coconino County_:
Fredonia, 3 (USBS); 2 mi. W Lees Ferry, 3 (MVZ); Jacobs Pools,
4000 ft., Houserock Valley, 15 (MVZ); 10 mi. S Jacobs Pools,
Houserock Valley, 2 (MVZ); Houserock Valley, 10 (USBS).

=Dipodomys ordii palmeri= (Allen)

_Dipodops ordii palmeri_ Allen, Bull. Mus. Comp. Zool., 8:187,
1881.

_Cricetodipus ordii palmeri_, Trouessart, Catalogus Mammalium,
1:581, 1897.

_Perodipus ordii palmeri_, Goldman, Proc. Biol. Soc. Washington,
30:113, May 23, 1917.

_Dipodomys ordii palmeri_, Grinnell, Journ. Mamm., 2:96, May 2,
1921.

_Cotypes._--Two males, adults, nos. 5886 and 5887, Mus. Comp.
Zool.; San Luis Potosí, Mexico; obtained on May 1, 1878, and
September 1, 1878, respectively, by Dr. Edward Palmer. (Types not
seen.)

_Range._--Eastern Zacatecas, Aguascaliente, northern Jalisco, San
Luis Potosí, Hidalgo, and probably Querétaro; marginal occurrences
are: Zacatecas, Canitas and Berriozobal; Aguascaliente, 1 mi. N
Chicalote; Jalisco, 9 mi. N Encarnación; Guanajuato, Celaya;
Hidalgo, Irolo.

_Diagnosis._--Size small (see measurements). Color dark, entire
dorsal surface (_h_) between Cinnamon and Sayal Brown, purest on
sides and flanks, upper parts strongly suffused with black;
posterior surfaces and fold of pinnae of ears, white; arietiform
markings, plantar surfaces of hind feet, inside of pinnae of ears,
dorsal and ventral stripes of tail, blackish. Skull small; nasals
long; rostrum long and narrow; interorbital region relatively
wide; degree of inflation of auditory bullae about average for
species; zygomatic arches light and bowed laterally; pterygoid
fossae subcircular; braincase but slightly vaulted.

_Comparisons._--From _Dipodomys ordii ordii_, _D. o. palmeri_
differs as follows: Size somewhat larger; color darker; skull
larger; nasals longer and flaring distally; interorbital width
greater; narrower across auditory bullae; interparietal region
narrower; breadth across maxillary arches greater; zygomatic arches
bowed laterally as opposed to relatively straight; pterygoid
fossae more nearly circular; rostrum longer and narrower.

From _Dipodomys ordii sennetti_, _D. o. palmeri_ differs in larger
size, darker color, longer tail and longer skull.

For comparisons with _Dipodomys ordii obscurus_ and _Dipodomys
ordii fuscus_ see accounts of those subspecies.

_Remarks._--Specimens from Berriozobal, Zacatecas, in the width of the rostrum and the configuration of the nasals, are intermediate between _Dipodomys ordii fuscus_ and _D. o. palmeri_. In color these animals are more nearly like typical representatives of _D. o. palmeri_. The animals from Jalisco and Guanajuato are not typical but the characters differentiating them from _D. o. palmeri_ are merely modifications of such slight degree that they all have been placed with that subspecies.

_Specimens examined._--Total, 56, distributed as follows:

=Zacatecas=: Canitas, 3 (USBS); Berriozobal, 10 (USBS).

=San Luis Potosí=: Potrero Santa Ana, 7.6 mi. S Matehuala, 2
(MVZ); Jesus Maria, 12 (USBS); 2 mi. NW San Luis Potosí, 8 (MVZ).

=Aguascalientes=: 1 mi. N Chicalote, 1900 m., 4 (MVZ).

=Jalisco=: 9 mi. N Encarnación, 1900 m., 1 (MVZ).

=Guanajuato=: Celaya, 8 (USBS).

=Hidalgo=: Ixmiquilpan, 1 (USBS); Irolo, 12 (USBS).

CONCLUSIONS

1. There are thirty-five recognizable subspecies of the species
_Dipodomys ordii_ of which four are herein, for the first time,
recognized by name. Three subspecies, _D. o. oklahomae_, _D. o.
sennetti_ and _D. o. compactus_, previously were regarded by most
authors as full species.

2. The species _Dipodomys ordii_ is divisible into six complexes,
or groups, of subspecies on both geographic and morphological
bases.

3. _Dipodomys ordii_ is the most generalized Recent species of the
genus.

4. The extremes of geographic variation in _Dipodomys ordii_ are
greater than in any other species of the genus.

5. Color, at least in _Dipodomys ordii_, does not seem to be
correlated with amount of moisture but rather with color of soil.

6. Clinal variation, from north to south, is shown in the
decreasing length of the nasals. This decrease in length of nasals
and resultant decrease in size of the nasal chamber may be
correlated with the decrease of humidity of the environment.

7. Subspeciation has been enhanced by the late Quaternary mountain
building which was prevalent over the western United States.

8. In general, the most primitive kinds of _Dipodomys ordii_ occur
at the periphery of the range of the species.

9. Natural selection plus geographical and ecological isolation
has undoubtedly been operative in speciation and in subspeciation.

10. _Dipodomys deserti_ is found to be the most specialized
species in the genus.

11. Six, rather than nine, groups of species are recognized, on
the basis of morphology, as comprising the genus _Dipodomys_.

12. The center of dispersal for the genus _Dipodomys_ appears to
have been in the southwestern United States and the adjoining part
of Mexico. A secondary center of differentiation is apparent in
the low, hot valleys of central California.

13. Parallel development of species is noted between _Dipodomys_
of the parental center and _Dipodomys_ of the isolated valleys of
central California; _Dipodomys_ in the California center is the
less specialized.

14. The trend of the dipodomyines, as indicated by the fossil
record, has been toward a saltatorial specialization with
consequent morphological changes.

15. The morphological change in the direction of saltatorial
specialization is clearly evident in the compacting and aligning
of the viscera as well as in the lengthening of the distal
segments of the hind legs and the tail, tufting of the tail,
enlargement of the auditory bullae, shortening of the neck and
fusion of the cervical vertebrae for stability and other
modifications of the skeleton.

TABLE 7

MEASUREMENTS (IN MILLIMETERS) OF DIPODOMYS ORDII

Key:

A Total length
B Length of tail
C Length of hind foot
D Greatest length of skull
E Greatest breadth across bullae
F Breadth across maxillary arches
G Width of rostrum
H Length of nasals
I Least interorbital width
J Basilar length