_Dipodomys ordii_ is a medium sized, relatively short-tailed, five-toed
species of a color about average for the genus. As in other members of
the genus, the hind legs and feet are disproportionately long as an
adaptation to the saltatorial mode of progression. The upperparts are
buffy, reddish or blackish, depending on the subspecies, but the entire
ventral surface, dorsal surfaces of the hind feet, supraorbital and
postauricular spots, forelimbs, hip stripes, lateral stripes of the tail
and the tail at the base are pure white. The skull has a relatively
short rostrum, moderate to large auditory bullae, relatively wide
interparietal, relatively wide maxillary arches and grooved upper
incisors.
The only other five-toed kangaroo rats with which _Dipodomys ordii_, at
places, shares its geographic range, are _Dipodomys panamintinus_ and
_Dipodomys microps_. _Dipodomys ordii_ can be distinguished from
_Dipodomys panamintinus_ by smaller size (for instance the hind foot is
shorter instead of longer than, 44 mm.) and narrower expanse of
maxillary arches in relation to breadth across the auditory bullae, and
from _Dipodomys microps_ by the awl-shaped, instead of chisel-shaped,
lower incisors.
The species _D. ordii_ is divisible into 35 subspecies, accounts of
which follow:
=Dipodomys ordii richardsoni= (Allen)
_Dipodops richardsoni_ Allen, Bull. Amer. Mus. Nat. Hist., 3:277,
June 30, 1891.
_Dipodomys phillippi_, Knox, Trans. Kansas Acad. Sci., 4:22, 1875,
(part--the part from Osborne, Kansas).
_Dipodomys phillipsi ordi_, Coues and Allen, Monogr. North
American Rodentia, p. 542, 1877 (part--the part from Ft. Cobb,
Oklahoma).
_Perodipus richardsoni_, Allen, Bull. Amer. Mus. Nat. Hist.,
7:260, August 21, 1895 (part--the part from Pendennis, Kansas).
_Cricetodipus richardsoni_, Trouessart, Catalogus Mammalium,
1:581, 1897.
_Perodipus montanus richardsoni_, Bailey, N. Amer. Fauna, 25:144,
October 1905 (part--the part from Canadian, Texas).
_Perodipus ordii richardsoni_, Goldman, Proc. Biol. Soc.
Washington, 30:113, May 23, 1917.
_Dipodomys ordii richardsoni_, Grinnell, Journ. Mamm., 2:96, May
2, 1921.
_Type._--Male, no. 3025/2345, Amer. Mus. Nat. Hist.; on one of the
sources of the Beaver River, Beaver County, Oklahoma; obtained on
October 26, 1887, by Jenness Richardson and John Rowley, Jr. (After
Allen, original description, type not seen.)
_Range._--Southwestern Nebraska, eastern Colorado, northeastern New
Mexico, Panhandle of Texas, and western parts of Oklahoma and
Kansas; marginal localities are: in Nebraska: Bladen, Haigler; in
Colorado: Olney; in New Mexico: Clayton; in Texas: 6 mi. S and 1
mi. W Quitaque, Vernon; in Oklahoma: 3 mi. S Cleo Springs; in
Kansas: Medora.
_Diagnosis._--Size large (see measurements). Color dark; entire
dorsal surface Cinnamon-Buff, purest on sides and flanks, upper
parts suffused with black; arietiform markings, pinnae of ears,
plantar surfaces of hind feet, dorsal and ventral stripes of tail,
blackish; in some specimens the ventral stripe of tail does not
extend to tip of pencil. Skull large; rostrum short and wide;
nasals long; zygomata relatively heavy; auditory bullae well
inflated and wide; thus with short rostrum giving appearance of
nearly equilateral triangle; upper incisors long and robust.
_Comparisons._--From _Dipodomys ordii luteolus_, _D. o.
richardsoni_ differs as follows: Size smaller in external
measurements except length of body which is longer; color darker,
except on plantar surfaces of hind feet and dorsal and ventral
stripes of the tail which are lighter; ventral stripe of tail, in
most specimens, continuous to end of pencil, whereas in _D. o.
luteolus_ ventral stripe is present on only proximal two-thirds;
skull larger in all measurements taken; zygomatic arch heavier;
auditory bullae relatively as well as actually more inflated;
external auditory meatus egg-shaped as contrasted to nearly round
in _D. o. luteolus_; pterygoid fossae rounded as compared to ovate
in _D. o. luteolus_.
From _Dipodomys ordii oklahomae_, _D. o. richardsoni_ differs as
follows: Size larger in all measurements taken; color darker in
all pigmented areas; skull larger in all respects; auditory bullae
larger and more inflated ventrally; jugal straight or nearly so
instead of bowed laterad; pterygoid fossae smaller; nasals
straight instead of inflated as a "bulb" distally.
For comparisons with _D. o. montanus_ and _D. o. evexus_, see
accounts of those subspecies.
Remarks.--This race of _Dipodomys ordii_ is readily distinguished from
_Dipodomys ordii evexus_, from the valley of the upper Arkansas River,
by larger size, larger skull and lighter color. Intergradation with
_Dipodomys ordii luteolus_ occurs rather freely in northeastern
Colorado, as indicated by specimens from 3 miles northeast of
Fitzsimmons, 6 miles east and 1 mile north of Denver and Barr Lake.
These specimens resemble _D. o. richardsoni_ in light color, greater
inflation of the auditory bullae and the shape of the pterygoid fossae
but resemble _D. o. luteolus_, to which they are here referred, in the
length of the nasals, the least interorbital width and in the external
measurements. In the southern part of the range of _D. o. richardsoni_
intergradation occurs with _Dipodomys ordii medius_, as at 6 miles
southwest of Muleshoe, Texas. Specimens from there have the long, wide
rostrum and narrow skull of _D. o. richardsoni_ but in the sum total of
their characters more closely resemble _D. o. medius_. At Texline,
Texas, the animals show intergradation in the length and shape of the
nasals and degree of convexity of the cranium but are referable to _D.
o. richardsoni_.
In fine, intergradation occurs at all points where the range of _D. o.
richardsoni_ touches that of any other geographic race. No one series of
it is as uniform as are most series of specimens of other known races.
_Dipodomys ordii richardsoni_ shows a mixture of characters.
Nevertheless, each of the populations studied has characters in most of
the animals that make this form recognizable as a taxonomic unit--a unit
that seems, as yet, not to have become stabilized even in the central
parts of its range.
Coues and Allen (1877:542) list specimens from Fort Cobb, Arkansas. It
is known that the Post Office Department, for administrative purposes,
attached certain towns and military installations in Indian Territory
(now Oklahoma) to the State of Arkansas. Thus it is apparent that Fort
Cobb, Arkansas, as recorded by Coues and Allen (_loc. cit._) is Fort
Cobb, Oklahoma. Specimens from Fort Cobb would be expected to be _D. o.
richardsoni_.
_Specimens examined._--Total, 351, distributed as follows:
=Nebraska=: _Adams County_: Bladen, 10 (AMNH). _Dundy County_:
Haigler, 1 (USBS).
=Colorado=: _Crowley County_: Olney, 1 (USBS). _Kiowa County_:
Chivington, 3 (USBS). _Otero County_: 18 mi. S La Junta, 4 (AMNH);
Higbee, 1 (USBS). _Bent County_: 4 mi. SE Las Animas, 4100 ft., 3
(MVZ). _Prowers County_: Lamar, 9 (LACM); 1 mi. S Lamar, 4000 ft.,
11 (KU). _Baca County_: Gaumes Ranch, 4600 ft., NW Corner, 1
(USBS).
=Kansas=: _Cheyenne County_: 23 mi. NW St. Francis, 5 (KU).
_Rawlins County_: 2 mi. NE Ludell, 2 (KU); 1-1/2 mi. W Ludell, 1
(KU). _Wallace County_: Lacey Ranch, 4-1/2 mi. E and 9 mi. S
Wallace, 1 (KU); unspecified, 2 (KU). _Logan County_: 5 mi. W
Elkader, 2 (KU); unspecified, 1 (UM). _Gove County_: unspecified,
1 (KU). _Trego County_: Banner, 8 (USNM); Parrington Ranch, 12 mi.
S Collyer, 2 (KU); unspecified, 8 (USNM). _Ellis County_: Ellis, 1
(USBS). _Lane County_: Pendennis, 10 (USBS). _Hamilton County_:
Coolidge, 2 (CNHM); 1 mi. E Coolidge, 5 (KU). _Pawnee County_: 1
mi. S Larned, 4 (KU); 2 mi. S and 1/4 mi. W Larned, 2 (KU); 3 mi.
S and 1-1/2 mi. W Larned, 10 (KU). _Edwards County_: Kinsley, 3
(USBS); 3-1/2 mi. E Kinsley, 5 (KU); S side Arkansas River, 2 mi.
S Kinsley, 1 (KU); 1 mi. W and 3-1/2 mi. S Kinsley, 9 (KU).
_Stafford County_: Little Salt Marsh, 15 mi. N and 3 mi. E
Stafford, 2 (KU). _Reno County_: Medora, 1 (UM); 2 mi. W and 1/2
mi. S Medora, 4 (KU). _Kiowa County_: 5 mi. N Belvidere, 1(KU).
_Pratt County_: Cairo, 2 (USBS). _Sedgwick County_: Wichita, 6
(AMNH). _Morton County_: 10 mi. N and 3 mi. E Elkhart, 34-1/2
(KU). _Seward County_: 1 mi. E Arkalon, 7 (KU); Liberal, 1 (KU);
unspecified, 1 (KU). _Meade County_: Meade, 1 (USNM); 13 mi. SW
Meade, 13 (6 AMNH; 7 KU); 17 mi. SW Meade, 2 (KU). _Clark County_:
12 mi. S Ashland, 1 (UM); unspecified, 3 (KU). _Barber County_:
Medicine Lodge, 4 (USBS); 1 mi. W Aetna, 3 (KU); 1/2 mi. W Aetna,
2 (KU); Aetna, 3 (KU); 1 mi. SW Aetna, 1 (KU); 1-1/2 mi. SW Aetna,
1 (KU); 1 mi. S Aetna, 5 (KU); unspecified, 2 (KU). _Harper
County_: 4-1/2 mi. NE Danville, 12 (KU); 2 mi. NE Runnymede, 3
(KU).
=New Mexico=: _Union County_: Clayton, Apache Canyon, 1 (USBS).
_Quay County_: Glenrio, 10 (LACM).
=Oklahoma=: _Cimmaron County_: Kenton, 1 (CM). _Beaver County_:
1-1/2 mi. N Beaver, 7 (KU); Beaver River, 8 (7 AMNH; 1 CNHM).
_Harper County_: 3 mi. S of Englewood, Kansas, 2 (MVZ); 4-1/2 mi.
N Laverne, 1 (UM). _Woods County_: 2 mi. W Edith, 1 (USBS); Alva,
12 (UM); Waynoka, 18 (UM); 3 mi. SW Waynoka, 1 (USBS). _Alfalfa
County_: 4 mi. SE Cherokee, 1 (USBS). _Ellis County_: Shattuck, 1
(USBS). _Woodward County_: Woodward, 9 (USBS). _Major County_: 3
mi. S Cleo Springs, 1 (USBS).
=Texas=: _Dallam County_: Texline, 8 (USBS). _Lipscomb County_:
Lipscomb, 8 (USBS). _Hemphill County_: 17 mi. NE Canadian, 1 (MVZ);
1 mi. W Canadian, along Red Deer River, 12 (MVZ); 1/2 mi. W
Canadian, along Red Deer River, 7 (MVZ); Canadian, 5 (USBS).
_Oldham County_: Tascosa, 6 (USBS). _Wheeler County_: 1 mi. W
Mobeetie, 2 (MVZ); Mobeetie, 8 (USBS); Wallace Ranch, SW Wheeler
County, 1 (TCWC). _Hall County_: Newlin, 1 (USBS). _Wilbarger
County_: Vernon, 5 (USBS). _Floyd County_: 6 mi. S and 1 mi. W
Quitaque, 1 (UM).
=Dipodomys ordii oklahomae= Trowbridge and Whitaker
_Dipodomys oklahomae_ Trowbridge and Whitaker, Journ. Mamm.,
21:343, August 14, 1940.
_Dipodomys ordii oklahomae_, Davis, Journ. Mamm., 23:332, August
14, 1942.
_Type._--Female, young adult, no. 265454, U. S. Nat. Mus., Biol.
Surv. Coll. (formerly Univ. of Oklahoma, Mus. Zool., no. 14517);
north bank of South Canadian River, 2-1/4 mi. S Norman, Cleveland
County, Oklahoma; obtained on March 16, 1934, by H. L. Whitaker,
original no., X-catalog no. 29312 of U. S. Nat. Mus.
_Range._--Known only from the South Canadian River Valley west of
Minco, Canadian County; and east to Lexington, Cleveland County,
Oklahoma.
_Diagnosis._--Size medium (see measurements). Color light, entire
dorsal surface near (_c_) Vinaceous-Buff, paler on sides with
great suffusion of white; arietiform markings, pinnae of ears,
plantar surfaces of hind feet, proximal ventral portion of tail
and dorsal stripe on tail, brownish. Skull of medium size; rostrum
wide; nasals short, projecting but slightly anteriorly to
incisors; zygomatic processes of maxillae heavy; bullae not
greatly inflated.
_Comparisons._--_Dipodomys ordii oklahomae_ differs from _D. o.
richardsoni_ as follows: Size smaller; color lighter in all
pigmented areas; ventral stripe of tail extending only one-fourth
the length rather than three fourths or to end of tail; skull
smaller in all measurements taken; rostrum heavier; auditory
bullae less inflated; pterygoid fossae larger; braincase slightly
more inflated; nasals more expanded distally; interparietal region
wider.
From _Dipodomys ordii ordii_, _D. o. oklahomae differs_ in: Size
larger in all measurements taken; color lighter in all pigmented
areas; ventral stripe of tail extending one fourth length of tail
rather than to end; skull larger in all respects; rostrum heavier;
zygomatic arches heavier; bullae more inflated ventrally; cutting
edge of upper incisors wider; pterygoid fossae larger; braincase
more vaulted; nasals more expanded distally; orbital region
larger; interparietal region wider.
_Remarks._--Trowbridge and Whitaker named this kangaroo rat as a full
species. The diagnostic characters were the length and breadth of the
rostrum and the relatively great inflation of the auditory bullae. Also,
_Dipodomys oklahomae_ was not known to intergrade with any other named
kinds. Davis (1942:332) treated _D. oklahomae_ as a subspecies of the
earlier named species _Dipodomys ordii_. Certain characters in specimens
from the type series of both _D. o. richardsoni_ and _D. oklahomae_,
such as the shape and configuration of the nasals, the over-all
proportion of the skull, tooth pattern and body proportions through
individual variation overlap and indicate that these two groups of
animals belong to the same species, even though animals from
intermediate geographic areas are not available to show actual
intergradation. My findings corroborate Davis' conclusion that _D.
oklahomae_ should stand as _Dipodomys ordii oklahomae_. In spite of the
great similarities shown by the two groups of animals there are still
sufficient diagnostic characters between the two groups to enable them
to be segregated easily as valid subspecies.
_Dipodomys ordii oklahomae_ is, for some unknown reason, restricted to a
limited geographic range. Specimens examined from the upper reaches of
the South Canadian River, farther westward, are all referable to _D. o.
richardsoni_ rather than, as would be expected, to _D. o. oklahomae_
since the habitat for these animals is continuous from the type locality
of _D. o. oklahomae_ to the upper reaches of the South Canadian River.
In length and shape of the nasals, degree of inflation of the auditory
bullae and width of the interorbital region these specimens from the
upper reaches of the South Canadian River are intergrades between _D. o.
richardsoni_ and _D. o. medius_. The range of _D. o. medius_ lies to the
south of that of _D. o. richardsoni_ and to the southwest of that of _D.
o. oklahomae_.
The present range of _D. o. oklahomae_, as now understood, is the
most eastern part of the range of the species _Dipodomys ordii_ and
of the genus _Dipodomys_. The existence of _D. o. oklahomae_ in this
area is a precarious one since its habitat is limited in extent and is
periodically flooded.
Although no specimens are known from the area where intergradation
between _D. o. oklahomae_ and _D. o. richardsoni_ would be expected
to occur, it would seem that when animals from this region
become available, intergradation will be shown to occur.
_Specimens examined._--Total, 8, all from Oklahoma, distributed as
follows: _Grady County_: 4 mi. N Minco, 1 (USBS). _Cleveland
County_: 2-1/4 mi. S Norman, 7 (6 OU; 1 USBS).
=Dipodomys ordii compactus= True
_Dipodomys compactus_ True, Proc. U. S. Nat. Mus., 11:160, January
5, 1889.
_Cricetodipus compactus_, Trouessart, Catalogus Mammalium, 1:581,
1897.
_Perodipus compactus_, Elliot, Field Columbian Museum, Zool. Ser.,
2:240, 1901.
_Dipodomys ordii compactus_, Davis, Journ. Mamm., 23:332, August
14, 1942.
_Type._--None designated but Poole and Schantz (1942:406) assumed
it to be a female, no. 19665/35227, only the skin found, from Padre
Island, Cameron County, Texas. April 3, 1888. Purchased from C. K.
Worthen.
_Range._--Padre and Mustang islands, Cameron County, Texas.
_Diagnosis._--Size medium (see measurements); tail short. Color
light; entire dorsal surface Light Ochraceous-Buff, purest on
sides and flanks, upper parts but lightly suffused with black. A
lighter color phase has entire dorsal surface Cartridge Buff,
purest on sides and flanks, upper parts but lightly washed with
black. In both phases, cheeks white; pinnae of ears, plantar
surfaces of hind feet, dorsal stripe of tail, ventral stripe of
tail (in most specimens) present on proximal third of tail only,
brownish. Skull small; rostrum narrow and long; nasals long;
auditory bullae inflated, but greatest breadth across bullae only
slightly more than breadth across zygomatic processes of maxillae;
interparietal region wide.
_Comparisons._--From _Dipodomys ordii sennetti_, _D. o. compactus
differs_ in: Size slightly less; color lighter in all pigmented
areas; skull smaller; auditory bullae slightly less inflated;
interorbital width less; interparietal region wider; nasals
longer.
From _Dipodomys ordii attenuatus_, _D. o. compactus_ differs in:
Body larger; tail shorter; normal color phase darker, and lighter
color phase lighter; skull larger; rostrum wider and longer;
nasals longer; interorbital region wider; auditory bullae
relatively as well as actually less inflated; interparietal region
wider; pterygoid fossae large and round as opposed to small and
ovoid.
Compared with _Dipodomys ordii medius_ and _Dipodomys ordii
ordii_, _D. o. compactus_ is smaller, lighter in color, and has
less inflated auditory bullae and a smaller skull.
_Remarks._--This subspecies of _Dipodomys ordii_ was originally
described as _Dipodomys compactus_ by True in 1889 and stood as a full
species until Davis (1942:332) relegated it to subspecific status under
_Dipodomys ordii_. Davis (_op. cit._) observed close resemblances in
external proportions, size of mastoid bullae, width of supraoccipital,
and size and shape of the interparietal, between _Dipodomys ordii_ and
_Dipodomys sennetti_ and therefore concluded that they were only
subspecies of one species. He observed that the difference between
_Dipodomys compactus_ and _Dipodomys sennetti_ was of approximately the
same degree as that between _Dipodomys sennetti_ and _Dipodomys ordii_.
From this he concluded that all three were subspecies of the one species
_Dipodomys ordii_.
In any sizeable sample of _Dipodomys sennetti_ there are crania closely
resembling those of _Dipodomys ordii ordii_ and others closely
resembling those of _Dipodomys compactus_. The external proportions of
both _D. sennetti_ and _D. compactus_ are duplicated in _D. ordii_ from
El Paso and conversely, specimens with the proportions of typical _D. o.
ordii_ occur in populations of _D. sennetti_ and _D. compactus_. Thus,
it appears that Davis' usage of the name _Dipodomys ordii compactus_
should stand although there may be a hiatus in geographic occurrence
between _D. ordii_ and _D. sennetti_, as of course there is between _D.
sennetti_ and _D. compactus_.
In _D. o. compactus_ there is a complete enamel ring around the occlusal
surface of each molariform tooth; in _D. o. ordii_ this ring is
incomplete lingually on each of the molariform teeth and labially on the
first three, and in some individuals of _D. o. sennetti_ the enamel ring
is complete and in others it is incomplete labially and lingually as in
_D. o. ordii_.
_Specimens examined._--Total, 44, all from Texas, distributed as
follows: _Nueces County_: 19 mi. S Port Aransas, Mustang Island, 27
(17 TCWC; 10 MVZ); Mustang Island, 17 (LACM).
=Dipodomys ordii sennetti= (Allen)
_Dipodops sennetti_ Allen, Bull. Amer. Mus. Nat. Hist., 3:226,
April 29, 1891.
_Cricetodipus sennetti_, Trouessart, Catalogus Mammalium, 1:581,
1897.
_Perodipus sennetti,_ Elliott, Field Columbian Museum, Zool. Ser.,
2:239, 1901.
_Dipodomys ordii sennetti_, Davis, Journ. Mamm., 23:332, August
14, 1942.
_Type._--Male, no. 3478/2733. Amer. Mus. Nat. Hist.; near
Brownsville, Cameron County, Texas; obtained on March 9, 1888, by
J. M. Priour. (After Allen, original description, type not seen.)
Type locality recorded by Bailey (1905:145) as "Santa Rosa, 85 mi.
SW Corpus Christi."
_Range._--Southern Texas, south of Corpus Christi; marginal
localities, all in Texas are: Somerset, 8 mi. NE Los Angeles, 8
mi. E Encinal, Santa Rosa, 28 mi. E Raymondville, 2 mi. S Riviera.
_Diagnosis._--Size small (see measurements). Color dark, entire
dorsal surface (_c_) between Pinkish Buff and Cinnamon-Buff,
purest on sides and flanks, upper parts mixed with black;
arietiform markings, pinnae of ears, dorsal and ventral stripes of
tail, plantar surfaces of hindfeet, brownish-black. Skull small;
auditory bullae but slightly inflated in relation to size of
skull; nasals slightly flaring distally; premaxillae extending but
slightly posterior to nasals; interorbital width relatively great;
external auditory meatus small; rostrum relatively long and wide;
zygomatic arches relatively heavy.
_Comparisons._--From _Dipodomys ordii ordii_, _D. o. sennetti_
differs in: Size smaller, tail shorter; color darker; skull
smaller; nasals longer; rostrum wider; auditory bullae less
inflated; external auditory meatus smaller; pterygoid fossae more
rounded; zygomatic arches heavier.
From _Dipodomys ordii medius_, _D. o. sennetti_ differs as
follows: Size smaller; color darker, but with less red in pelage;
skull markedly smaller in all respects.
From _Dipodomys ordii compactus_, _D. o. sennetti_ differs in:
Size somewhat less; color darker; skull with total length greater;
orbit smaller; least interorbital width greater; braincase more
inflated; width across auditory bullae more; interparietal region
wider; external auditory meatus larger; medial part of audital
portion (see Howell, 1932) of auditory bullae larger.
_Remarks._--_Dipodomys sennetti_, along with _Dipodomys compactus_,
was regarded by Davis as conspecific with _Dipodomys ordii_.
Reasons for placing these two kinds of kangaroo rats as subspecies
of _D. ordii_ are given in the account of _Dipodomys ordii compactus_.
This subspecies is known only from north of the Rio Grande
which may serve as a barrier to the spread of the animal into
northern Tamaulipas.
_Specimens examined._--Total, 20, all from Texas, distributed as
follows: _Atascosa County_: Somerset, 2 (TCWC). _LaSalle County_: 8
mi. NE Los Angeles, 1 (TCWC); 8 mi. E Encinal, 1 (TCWC). _Kleberg
County_: 2 mi. S Riviera, 9 (TCWC). _Jim Hogg County_: Hebronville,
8 (LACM). _Brooks County_: Falfurrias, 2 (LACM). _Willacy County_:
28 mi. E Raymondville, 2 (TCWC).
=Dipodomys ordii evexus= Goldman
_Dipodomys ordii evexus_ Goldman, Journ. Washington Acad. Sci.,
23:468, October 15, 1933.
_Perodipus montanus richardsoni_ Warren, Mammals of Colorado, p.
76, 1910 (part--the part from Salida, Colorado).
_Type._--Male, adult, no. 150990, U. S. Nat. Mus. Biol. Surv.
Coll.; Salida, Chaffee County, Colorado (altitude 7000 ft.);
obtained on November 10, 1907, by Merritt Cary, original no. 1245.
_Range._--Upper Arkansas River Valley of south-central Colorado,
from Salida to Pueblo.
_Diagnosis._--Size large (see measurements). Color dark, entire
dorsal surface between (_16´´_) Pinkish Cinnamon and Cinnamon-Buff,
purest on sides and flanks, upper parts strongly suffused with
black; arietiform markings, pinnae of ears, plantar surfaces of
hind feet and dorsal and ventral stripes of tail, blackish. Skull
of medium size; rostrum short and wide; nasals short; auditory
bullae but slightly inflated; braincase but slightly vaulted.
_Comparisons._--From _Dipodomys ordii richardsoni_, _D. o. evexus_
differs as follows: Size smaller in all measurements taken; color
darker; ears darker, dorsal and ventral stripes on tail darker,
arietiform markings darker and more distinct, plantar surfaces of
hind feet darker; skull smaller in all measurements; length, as
expressed in percentage of width of skull, greater in _D. o.
evexus_ (66 per cent in _D. o. evexus_, 62 per cent in _D. o.
richardsoni_ which gives the appearance of a long, narrow skull as
contrasted with a rather short, wide skull); auditory bullae less
expanded laterally, posteriorly and ventrally; interparietal
region relatively wider in proportion to greatest width across
auditory bullae; cutting edge of upper incisors narrower;
pterygoid fossae smaller and more nearly circular.
Compared with _Dipodomys ordii luteolus_, _D. o. evexus_ differs
as follows: Size somewhat smaller in external measurements; color
darker in all pigmented areas; skull smaller in two of the seven
measurements taken but in the other five measurements somewhat
larger; auditory bullae less inflated; cutting edge of upper
incisors narrower; zygomatic arch heavier; pterygoid fossae
smaller and more nearly circular; external auditory meatus ovoid
as contrasted to nearly circular; paroccipital processes smaller.
From _Dipodomys ordii nexilis_, _D. o. evexus_ differs in: Color
darker; rostrum wider and shorter; interorbital region wider;
breadth across maxillary arches greater; auditory bullae less
inflated; interparietal region larger; zygomatic arches heavy and
bowed laterad; molariform teeth smaller; cutting edge of upper
incisors narrower.
For comparison with _Dipodomys ordii montanus_ see account of that
subspecies.
_Remarks._--This race of kangaroo rat, described from the upper
Arkansas River Valley, closely resembles _Dipodomys ordii luteolus_
but differs in darker color, slightly smaller body and larger skull.
No evidence of intergradation with any other race was noted. To the
south the range of _D. o. evexus_ is separated from that of _D. o.
montanus_ by a high, transverse ridge of the Rocky Mountains which is
inhospitable to these animals. Much territory inhospitable to
_Dipodomys_ intervenes also between the ranges of _D. o. evexus_ and _D.
o. luteolus_, but there are areas connecting the northern part of the
range of _D. o. evexus_ and the southwestern part of the known range of
_D. o. luteolus_, in which _Dipodomys_ may occur. If kangaroo rats occur
in these areas it is to be expected that they will show intergradation
between the two subspecies concerned.
_Specimens examined._--Total, 24, all from Colorado, distributed as
follows: _Chaffee County_: Salida, 10 (3 USBS; 7 AMNH). _Fremont
County_: Canyon City, 13 (USBS). _Pueblo County_: Pueblo, 1 (USBS).
=Dipodomys ordii medius= new subspecies
_Perodipus montanus richardsoni_, Bailey, N. Amer. Fauna, 25:144,
October, 1905 (part--the part from Santa Rosa, New Mexico).
_Type._--Male, no. 118526, U. S. Nat. Mus. Biol. Surv. Coll.; Santa
Rosa, Guadalupe County, New Mexico; obtained on October 5, 1902, by
Jas. H. Grant, original no. 565.
_Range._--From north-central New Mexico, southeastward to
west-central Texas; marginal localities are, in New Mexico: 15 mi.
N Ojo Caliente, Gallina Mts., Deer Creek, San Pedro; in Texas: 20
mi. N Monahans, Colorado, 7 mi. E Post, 6 mi. SW Muleshoe.
_Diagnosis._--Size medium (see measurements). Color dark; entire
dorsal surface (_14''_) between Orange-Cinnamon and Cinnamon,
purest on sides and flanks, dorsal surface lightly washed with
black; arietiform markings, pinnae of ears, plantar surfaces of
hind feet, dorsal and ventral stripes of tail, brownish-black.
Skull of medium size; nasals long; medial mastoid portion of
auditory bullae well inflated caudad; braincase vaulted; external
auditory meatus small; rostrum short and truncate; medial auditory
portion of auditory bullae relatively little inflated; pterygoid
fossae ovate; zygomatic arches slender and relatively straight;
junction of jugal and zygomatic process of maxilla heavy.
_Comparisons._--From _Dipodomys ordii richardsoni_, _D. o. medius_
differs as follows: Tail longer; hind foot shorter; color darker;
arietiform markings more distinct; white lateral stripes of tail
narrower; ventral stripe of tail in most specimens complete to end
of pencil; postauricular spots less pronounced; hip stripe
narrower and in some specimens almost obliterated; skull smaller
in all measurements taken; angle of dorsal extension of premaxilla
with zygomatic process of maxilla more nearly 90°; braincase more
vaulted; medial mastoid portion of auditory bullae more inflated,
and coming to more of a point; medial auditory portion of auditory
bullae more inflated ventrally; rostrum shorter and narrower;
external auditory meatus smaller.
From _Dipodomys ordii montanus_, _D. o. medius_ differs in: Color
lighter in all pigmented areas; skull larger in all respects;
rostrum shorter and heavier; bullae more inflated; zygomata, while
nearly straight, are bowed slightly laterally; pterygoid fossae
more ovate; foramen magnum larger; pterygoid foramina smaller.
Compared with _Dipodomys ordii ordii_ and _Dipodomys ordii
sennetti_, _D. o. medius_ is larger and darker. The skull is also
larger in all measurements taken.
Compared with _Dipodomys ordii longipes_, _D. o. medius_ is darker
and smaller.
_Remarks._--This hitherto undescribed race of _Dipodomys ordii_
can readily be distinguished from any of its near neighbors by the
characters set forth under diagnosis and comparisons.
Intergradation is noted with _D. o. ordii_, _D. o. longipes_, _D. o.
montanus_ and _D. o. richardsoni_. Among named races _D. o. medius_
shows closest affinities with _D. o. richardsoni_ but the two are easily
separable. The northwestern extremity of the range of _D. o. medius_ is
an area of intergradation in which no specimens are clearly of one
subspecies or the other. In specimens from 5 miles east of Abiquiu, New
Mexico, three-way intergradation occurs. These animals are like _D. o.
medius_ in size, _D. o. longipes_ in color and their cranial proportions
are as in _D. o. montanus_. At Deer Creek, New Mexico, and at Monahans,
Texas, the animals show intergradation in size of body and agree with
_D. o. ordii_ in cranial proportions. In specimens from 6 miles
southwest of Muleshoe, Texas, intergradation with _D. o. richardsoni_ in
the shape of the skull and width of the rostrum is noted. In the sum
total of characters studied, however, these specimens are referable to
_D. o. medius_.
_Specimens examined._--Total, 129, distributed as follows:
=New Mexico=: _Rio Arriba County_: 2 mi. SE El Rito, 2 (KU); Rio
Alamosa, 15 mi. N Ojo Caliente, 1 (USBS); 6 mi. E Abiquiu, 4
(USBS); Rinconada, 5 (USBS); Espanola, 6 (USBS). _Sandoval
County_: 12 mi. NW Alameda, 5500 ft., 3 (MVZ). _Santa Fe County_:
Seton's Ranch, near Santa Fe, 1 (USBS); 8 mi. SW Santa Fe, 8 (KU);
San Pedro, 3 (USBS). _San Miguel County_: Pecos, 2 (USBS); 3 mi. S
Pecos, 2 (USBS); Rowe, 6 (LACM). _Bernallilo County_: Bear Canyon,
Sandia Mountains, 7 (USBS); Pajarito, 3 (MVZ). _Guadalupe County_:
Santa Rosa, 10 (USBS). _Lincoln County_: 44 mi. NW Roswell, 5
(MVZ). _De Baca County_: 8 mi. N Fort Sumner, 9 (USBS). _Roosevelt
County_: Kenna, 4 (LACM). _Curry County_: 4 mi. W and 2-3/4 mi. N
Clovis, 1 (MVZ). _Chaves County_: 40 mi. N Roswell, 2 (USBS); 35
mi. N Roswell, 2 (USBS); 15 mi. NE Roswell, 8 (LACM); Stinking
Springs Lake, 3 (USBS).
=Texas=: _Bailey County_: 6 mi. SW Muleshoe, 5 (UM); 9 mi. SW
Muleshoe, 2 (UM). _Garza County_: 7 mi. E Post, 5 (UM). _Martin
County_: Stanton, 4 (USBS). _Howard County_: 6 mi. NE Coahoma, 7
(UM); 1 mi. S Coahoma, 1 (UM); 5 mi. W Big Springs, 2400 ft., 1
(MVZ). _Mitchell County_: Colorado, 5 (USBS). _Winkler County_: 20
mi. N Monahans, 1 (USBS). _Ward County_: Monahans, 1 (USBS).
=Dipodomys ordii obscurus= (Allen)
_Perodipus obscurus_ Allen, Bull. Amer. Mus. Nat. Hist., 19:603,
November 12, 1903.
_Dipodomys ordii obscurus_, Grinnell, Journ. Mamm., 2:96, May 2,
1921.
_Type._--Male, adult, no. 20957, Amer. Mus. Nat. Hist.; Rio Sestin,
northwestern Durango, Mexico; obtained on April 13, 1903, by J. H.
Batty. (Type not seen.)
_Range._--Northwestern and northern Durango, Mexico; marginal
localities are: Rosario, Rio Sestin, Mt. San Gabriel, Rio del
Bocas, Villa Ocampo.
_Diagnosis._--Size small (see measurements). Color dark, entire
dorsal surface (_16''_) between Pinkish Cinnamon and
Cinnamon-Buff, purest on sides, flanks and cheeks, upper parts
strongly suffused with black; arietiform markings, plantar
surfaces of hind feet, pinnae of ears, dorsal and ventral stripes
of tail, brownish. Skull of medium size, nasals long and flared
distally; rostrum long and narrow; interorbital region relatively
narrow; auditory bullae less inflated than in _Dipodomys ordii
palmeri_; interparietal region narrow; zygomatic arches heavy and
bowed laterad; pterygoid fossae ovoid; braincase but slightly
vaulted.
_Comparisons._--From _Dipodomys ordii palmeri_, _D. o. obscurus_
differs in: Size larger; color lighter; nasals shorter and more
flared distally; interorbital width less; lacrimal processes
larger; auditory bullae less inflated; pterygoid fossae ovoid as
opposed to subcircular; zygomatic arches heavier; rostrum shorter
and wider.
From _Dipodomys ordii ordii_, _D. o. obscurus_ differs as follows:
Size smaller; color darker; skull smaller; nasals longer; rostrum
narrower and shorter; interorbital width greater; interparietal
region narrower; narrower across auditory bullae; zygomatic arches
heavier and more bowed laterally; pterygoid fossae more ovoid;
breadth across maxillary arches greater; external auditory meatus
smaller.
With _Dipodomys ordii attenuatus_ and _Dipodomys ordii sennetti_,
_D. o. obscurus_ needs no comparison since it is larger and darker
than either of those subspecies and can readily be told from the
latter by the greater expansion of the auditory bullae.
For comparison with _Dipodomys ordii fuscus_ see account of that
subspecies.
_Remarks._--_D. o. obscurus_ seemingly is not a far-ranging subspecies.
The only examples referable to it come from a relatively restricted
area of Durango, Mexico. One specimen from Rio del Bocas, Durango,
is not typical and shows the characters described for the animals
from Chihuahua City and from Casas Grandes. I have considered the
possibility that this specimen is an intergrade between _D. o.
obscurus_ and an unnamed subspecies ranging to the northeastward. The
other specimens in the series from Rio del Bocas are typical of _D. o.
obscurus_.
_Specimens examined._--Total, 69, all from Durango, distributed as
follows: Rosario, 20 (AMNH); Villa Ocampo, 5 (AMNH); Rio Sestin, 30
(28 AMNH; 2 CNHM); Mt. San Gabriel, 2 (AMNH); Rio del Bocas, 11
(AMNH); Rancho Santuario, 1 (AMNH).
[Illustration: FIG. 24. Known occurrences and probable geographic range
of the subspecies of _Dipodomys ordii_ in the southeastern fourth of the
range of the species.
1. _D. o. richardsoni_ 2. _D. o. oklahomae_ 3. _D. o. compactus_ 4.
_D. o. sennetti_ 6. _D. o. medius_ 7. _D. o. obscurus_ 14. _D. o.
ordii_ 16. _D. o. extractus_ 23. _D. o. idoneus_ 29. _D. o.
attenuatus_ 30. _D. o. fuscus_ 31. _D. o. longipes_ 35. _D. o.
palmeri_ ]
=Dipodomys ordii terrosus= Hoffmeister
_Dipodomys ordii terrosus_ Hoffmeister, Proc. Biol. Soc.
Washington, 55:165, December 31, 1942.
_Dipodomys phillipsi ordi_, Coues and Allen, Monogr. North
American Rodentia, p. 541, August, 1877 (part--the part from
Yellowstone River, Montana).
_Perodipus montanus richardsoni_, Cary, N. Amer. Fauna, 49:124,
December, 1926 (part--the part from Glendive, Montana).
_Type._--Male, no. 93477, Mus. Vert. Zool., Univ. California;
Yellowstone River, 5 mi. W Forsyth, 2,750 ft., Rosebud County,
Montana; obtained on June 2, 1940, by J. R. Alcorn, original no.
1528.
_Range._--Extreme southwestern Saskatchewan and southeastern
Alberta, eastern half of Montana, northern Wyoming and probably
extreme western North Dakota; marginal localities are: 50 mi. W
Swift Current, Saskatchewan; "near Medicine Hat," Alberta; in
Wyoming, Sheep Creek, and 23 mi. SW Newcastle; in Montana,
Medicine Rocks (14 mi. NE Ekalaka), and Glendive.
_Diagnosis._--Size large (see measurements). Color dark, entire
dorsal surface near (_c_) Ochraceous-Buff, purest on sides and
flanks; upper parts mixed with black; arietiform markings, pinnae
of ears, dorsal and ventral stripes of tail and plantar surfaces
of hind feet brownish-black. Skull large; rostrum short, wide and
deep; braincase slightly vaulted; auditory bullae markedly
inflated ventrally; zygomatic arches heavy and bowed laterad;
upper incisors long and robust.
_Comparisons._--From _Dipodomys ordii priscus_, _D. o. terrosus_
differs as follows: Size larger in all measurements taken, except
for length of hind feet, which is less; color darker in all
pigmented areas; skull larger in all parts measured except width
of interparietal, which is less; auditory bullae more inflated
ventrally; zygomatic processes of maxillae wider; rostrum deeper
and shorter.
From _Dipodomys ordii richardsoni_, _D. o. terrosus_ differs as
follows: Size larger; color darker in all pigmented areas; ventral
stripe of tail extending farther distally; skull larger except in
width across auditory bullae, which is the same.
For comparison with _Dipodomys ordii luteolus_ see account of that
subspecies.
_Remarks._--As noted in the comparisons, _D. o. terrosus_ is larger and
darker than _D. o. priscus_, _D. o. luteolus_ or _D. o. richardsoni_,
its closest geographic neighbors, and does not resemble any of them, but
rather resembles _D. o. longipes_ and _D. o. evexus_ in size and
appearance, both of which are distantly removed geographically.
Like other subspecies of the species _D. ordii_, _D. o. terrosus_
prefers sandy soils to those of any other type. Two miles east and 1
mile south of Forsyth, Montana, animals were trapped on lenses of sandy
soil. These lenses alternated with areas of black loam of similar size.
It was noteworthy that burrows were found only in the areas of sandy
soil, although paths used by the rats when foraging did extend onto and
several crossed the lenses of black loam. We were not permitted to
excavate any of these burrows, but conversation with farmers of the
immediate vicinity indicated that the burrows were not deep. An
eight-inch disc would frequently plow out nests and food caches. It was
said that each of several caches contained as much as a peck of wheat.
Intergradation was noted in animals from 23 miles southwest of Newcastle
and Arvada, Wyoming. In animals from both localities the pterygoid
fossae are more as in _D. o. luteolus_ but referable to _D. o.
terrosus_. The specimens from Arvada, although immature, possessed
cranial characters which were intermediate between those of _D. o.
terrosus_ and _D. o. luteolus_ but the specimens are referable to the
former.
_Specimens examined._--Total, 74, distributed as follows:
=Montana=: _Petroleum County_: 24 mi. N Roundup, 8 mi. SW
Flatwillow, 2 (UM). _Garfield County_: Jordan, 10 (1 UM; 2 MVZ; 7
AMNH). _Dawson County_: Glendive, 9 (USNM). _Musselshell County_:
Harvey Ranch, Melstone, 3 (MVZ). _Rosebud County_: Yellowstone
River, 5 mi. W Forsyth, 2750 ft., 7 (MVZ); 2 mi. E and 1 mi. S
Forsyth, 2600 ft., 8 (KU). _Custer County_: Miles City, 1 (USBS).
_Yellowstone County_: Billings, 2 (1 USBS; 1 MVZ). _Big Horn
County_: Fort Custer, 1 (USBS); Crow Agency, 1 (USBS). _Powder
River County_: Powderville, 4 (USBS). _Carter County_: Medicine
Rocks, 15 mi. N Ekalaka, 2 (USBS); Medicine Rocks, 14 mi. N
Ekalaka, 2 (USBS); Clark's Fork, 1 (USBS).
=Wyoming=: _Big Horn County_: Dry Creek, 10 mi. W Germania, 1
(USBS); 3 mi. E Germania, 1 (USBS); Greybull, 2 (USBS); Bighorn
Basin, 1 (USBS). _Sheridan County_: Arvada, 8 (USBS). _Campbell
County_: Little Powder River, 1 (USBS). _Weston County_:
Newcastle, 2 (USBS); 23 mi. SW Newcastle, 4 (USBS). _Fremont
County_: Wilson's Ranch, Sheep Creek, S base Owl Creek Mountains,
1 (USBS).
_Additional records._--=Canada= (Anderson, 1946:131): _Alberta_:
near Medicine Hat, 1; _Saskatchewan_: near Shackleton, 45-50 mi.
NW Swift Current, 1; near Tompkins, 50 mi. W Swift Current, 1.
=Dipodomys ordii fremonti= Durrant and Setzer
_Dipodomys ordii fremonti_ Durrant and Setzer, Bull. Univ. Utah, 35
(no. 26):21, June 30, 1945.
_Type._--Female, no. 15661, Carnegie Museum, Pittsburgh,
Pennsylvania; Torrey, 7000 ft., Wayne County, Utah; obtained on
July 19, 1938, by W. F. and F. H. Wood, original no. 1562.
_Range._--Known only from the type locality.
_Diagnosis._--Size small (see measurements). Color dark, entire
dorsal surface Cinnamon-Buff, purest on sides, flanks and cheeks;
upper parts strongly suffused with black; arietiform markings,
pinnae of ears, plantar surfaces of hind feet, dorsal and ventral
stripes of tail, brownish. Skull small; upper incisors long;
rostrum deep; jugal bowed laterally; diastema long; upper
molariform tooth-row long.
_Comparisons._--From _Dipodomys ordii panguitchensis_, _D. o.
fremonti_ differs in: Color lighter in all pigmented areas,
particularly ears which are light brown in _D. o. fremonti_ and
black in _D. o. panguitchensis_; skull larger in all measurements
taken; upper incisors longer; rostrum deeper; auditory bullae
deeper; jugal bowed laterally rather than straight; diastema
longer.
From _Dipodomys ordii cupidineus_, _longipes_, _nexilis_,
_uintensis_ and _sanrafaeli_, _D. o. fremonti_ can readily be
distinguished by its smaller size and generally darker color.
_Remarks._--This subspecies of _Dipodomys ordii_ inhabits the upper
reaches of the Fremont River in west-central Wayne County, Utah.
_D. o. fremonti_ appears to be isolated and is known only from the
type locality. _D. o. fremonti_ is so remarkably different from any
other subspecies of _Dipodomys ordii_ that a long period of isolation
from the ancestral stock (which probably gave rise also to _Dipodomys
ordii utahensis_ and _Dipodomys ordii panguitchensis_) is indicated.
Although intergradation is not known to occur with other kinds,
differentiation has not progressed far enough for these animals to be
recognized as a distinct species.
The subspecies closest, geographically, to _D. o. fremonti_ is _D. o.
cupidineus_ from which _D. o. fremonti_ differs more than from any of
the other named forms.
_Specimens examined._--Total, 9, from Utah, as follows: _Wayne
County_: Torrey, 7000 ft., 9 (CM).
=Dipodomys ordii uintensis= Durrant and Setzer
_Dipodomys ordii uintensis_ Durrant and Setzer, Bull. Univ. Utah,
35 (no. 26):27, June 30, 1945.
_Perodipus longipes_, Allen, Bull. Amer. Mus. Nat. Hist., 8:246,
November 1896 (part--the part from Uncompahgre Indian Reservation,
Utah).
_Dipodomys ordii luteolus_, Moore, Journ. Mamm., 11:88, February,
1930 (part--the part from Vernal, Utah).
_Type._--Male, adult, no. 11634, Carnegie Museum, Pittsburgh,
Pennsylvania; Red Creek, 6,700 ft., 2 mi. N Fruitland, Duchesne
County, Utah; obtained on August 15, 1936, by J. K. and M. T.
Doutt, original no. 3433.
_Range._--Uinta basin of the White, Green and Duchesne river
drainage in northeastern Utah; marginal occurrences are: 2 mi. N
Fruitland, 10 mi. S Ouray, Vernal.
_Diagnosis._--Size large (see measurements); hind foot short.
Color dark; entire dorsal surface, near (_c_) Cinnamon-Buff,
purest on sides and flanks, with moderate 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; frontomaxillary suture convex mediad;
lacrimal process large; styloid process projects, on ventral
surface of tympanic bulla, beyond middle of external auditory
meatus; nasals flared distally.
_Comparisons._--From _Dipodomys ordii priscus_, _D. o. uintensis_
differs in: Hind foot shorter; color darker; styloid process
projects on ventral part of tympanic bulla well anterior to middle
of external auditory meatus as opposed to projecting to middle;
depth of foramen magnum, expressed in percentage of width across
posterior margin of occipital condyles, greater (86 per cent in
_D. o. uintensis_ and 81 per cent in _D. o. priscus_);
frontomaxillary suture convex mediad as opposed to nearly
straight; lacrimal processes larger; nasals more flared distally.
From _Dipodomys ordii nexilis_, _D. o. uintensis_ differs as
follows: Size smaller; color lighter; interorbital breadth greater;
frontomaxillary suture convex mediad as opposed to concave;
lacrimal processes larger; nasals more flared distally; narrower
across auditory bullae; basal length greater; zygomatic arches
bowed laterad as opposed to relatively straight.
From _Dipodomys ordii longipes_, _D. o. uintensis_ differs as
follows: Size smaller; color darker; auditory bullae wider, longer
and deeper; frontomaxillary suture convex mediad as opposed to
nearly straight; greatest breadth across auditory bullae less.
For comparison with _Dipodomys ordii sanrafaeli_ see account of
that subspecies.
_Remarks._--This large, rather dark race inhabits the desert valleys
of the White, Green and Duchesne rivers in northeastern Utah. The
race nearest geographically, as well as morphologically, is _Dipodomys
ordii priscus_. Intergradation occurs with the latter subspecies
at Vernal, Uintah County, in cranial measurements and in color.
On the basis of color alone _D. o. uintensis_ can be distinguished from
_D. o. sanrafaeli_, the geographic race to the south. Specimens from
Jensen are intermediate in color and cranial measurements between
_Dipodomys ordii nexilis_ and _D. o. uintensis_ but are referable to the
latter.
_Specimens examined._--Total, 40, all from Utah, distributed as
follows: _Duchesne County_: Red Creek, 6700 ft., 2 mi. N Fruitland,
4 (CM); 10 mi. S Myton, 1 (UU); 20 mi. S Myton, 1 (RH). _Uintah
County_: Vernal, 1 (BYU); 20 mi. E Ouray, 5 (CM); Junction Green
and White rivers, 4800 ft., 2 mi. S Ouray, 5 (CM); Pariette Bench,
5000 ft., 8 mi. S Ouray, 8 (CM); Desert Springs, 10 mi. S Ouray, 4
(CM); Pariette Bench, 12 mi. S Ouray, 2 (CM); Jensen, 5 (BYU); E
side Green River, 3 mi. S Jensen, 4 (CM).
=Dipodomys ordii sanrafaeli= Durrant and Setzer
_Dipodomys ordii sanrafaeli_ Durrant and Setzer, Bull. Univ. Utah,
35 (no. 26):26, June 30, 1945.
_Dipodomys ordii longipes_, Stanford, Journ. Mamm., 12:360,
November, 1931 (part--the part from King's Ranch, Utah).
_Type._--Female, adult, no. 4612, Museum of Zoology, University of
Utah; 1-1/2 mi. N Price, 5567 ft., Carbon County, Utah; obtained
on June 5, 1940, by Ross Hardy and H. Higgins, original no. 1901.
_Range._--East-central Utah, east into west-central Colorado.
Marginal occurrences are: in Utah, 12 mi. E Price, 1-1/2 mi. N
Price, Notom, King's Ranch, 12 mi. SW Green River, 16 mi. NW Moab;
in Colorado, State Line and Grand Junction.
_Diagnosis._--Size large (see measurements). Color dark, entire
dorsal surface 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-black. Skull large;
pterygoid fossae ovoid; lacrimal processes small; width across
maxillary arches relatively great; auditory bullae well inflated;
diastema short.
_Comparisons._--From _Dipodomys ordii longipes_, _D. o.
sanrafaeli_ differs as follows: Size smaller; color lighter, more
cinnamon, pinnae of ears lighter; skull smaller; auditory bullae
smaller; pterygoid fossae ovoid rather than round; wider across
occipital condyles; narrower across zygomatic processes of
maxillae.
From _Dipodomys ordii cupidineus_, _D. o. sanrafaeli_ can be
recognized by its larger size, lighter color and larger skull.
For comparisons with _Dipodomys ordii nexilis_, _Dipodomys ordii
priscus_ and _Dipodomys ordii uintensis_ see accounts of those
subspecies.
_Remarks._--Intergradation between _Dipodomys ordii cupidineus_ and _D.
o. sanrafaeli_ is noted in the intermediate size of body in a single
specimen from Notom. Intergradation in color and cranial characters
occurs between _Dipodomys ordii nexilis_ and _D. o. sanrafaeli_ in
specimens from 16 miles northwest of Moab. All these specimens, however,
are referable to _D. o. sanrafaeli_.
Animals from that part of the range of _D. o. sanrafaeli_ west of the
Green River are typical while those to the east of the river are all
intergrades. Animals from 16 miles northwest of Moab, Utah, and from
three localities in Colorado, even though intergrades with _D. o.
nexilis_, are all referable to _D. o. sanrafaeli_. It appears that the
Green River does not act as a complete barrier in this area since in the
winter it occasionally freezes over, thus allowing the animals to cross.
It is thought that kangaroo rats do not hibernate but remain more or
less active throughout the winter. Man-made conveniences, such as
bridges, might also serve as means of dispersal, permitting these
animals to cross otherwise prohibitive barriers. Where there are no
bridges across the Green River, farther to the south, the rats
apparently do not cross the river; steep, rocky canyon-walls and the
lack of ice on the water in winter lessen the chances of small mammals
crossing from one side to the other.
_Specimens examined._--Total, 30, distributed as follows:
=Utah=: _Carbon County_: 12 mi. NE Price, 2 (CM); 3 mi. NE Price,
1 (RH); 1-1/2 mi. N Price, 2 (1 RH; 1 UU); Wellington, 1 (RH).
_Emery County_: "San Rafael, 21 mi. out," 1 (USAC); 12 mi. SW
Green River, 2 (CM). _Grand County_: 1 mi. E Green River, 1 (MVZ);
16 mi. NW Moab, 2 (CM). _Wayne County_: Notom, 1 (BYU). _Garfield
County_: King's Ranch, 4800 ft., 3 (2 UU; 1 USAC).
=Colorado=: _Mesa County_: State Line, 11 (MVZ); Fruita, 1 (USBS);
Grand Junction, 2 (USBS).
=Dipodomys ordii panguitchensis= Hardy
_Dipodomys ordii panguitchensis_ Hardy, Proc. Biol. Soc.
Washington, 55:90, June 25, 1942.
_Type._--Male, adult, no. 4375, Museum of Zoology, University of
Utah; one mile south of Panguitch, 6666 ft., Garfield County,
Utah; obtained on August 31, 1940, by Ross Hardy, original no.
2151.
_Range._--Known only from the type locality.
_Diagnosis._--Size small (see measurements). Color dark, entire
dorsal surface near Olive-Brown, purest on sides and flanks, upper
parts strongly suffused with black; cheeks white; arietiform
markings, pinnae of ears, plantar surfaces of hind feet, dorsal
and ventral stripes of tail which are wider than white lateral
stripes, blackish. Skull small; rostrum relatively short and wide;
interorbital region wide; interparietal region wide; foramen
magnum elongate dorsoventrally; pterygoid fossae ovoid.
_Comparisons._--From _Dipodomys ordii utahensis_, which it closely
resembles, _D. o. panguitchensis_ differs in: Size larger; color
darker; interparietal region wider; foramen magnum elongate
dorsoventrally as opposed to nearly round; pterygoid fossae ovoid
as opposed to nearly round.
This subspecies can be distinguished from _Dipodomys ordii
fetosus_, _Dipodomys ordii celeripes_ and _Dipodomys ordii
cupidineus_ by its darker color and generally larger size.
For comparisons with _Dipodomys ordii cinderensis_ and _Dipodomys
ordii fremonti_ see accounts of those subspecies.
_Remarks._--This geographic race inhabits the upper reaches of
the Sevier River Valley in the vicinity of Panguitch, Utah. Natural
barriers to kangaroo rats, such as the Cedar Mountains to the west,
high plateau country to the south, the Paunsaugunt Plateau to the
east and the narrow canyons of the Sevier River to the north prevent
these animals from extending their range or from coming into physical
contact with any adjacent geographic races. This isolation has resulted
in a fairly stable population. Some animals, however, show characters,
such as the width of the rostrum, and the shape and length of the
nasals which are intermediate between those of topotypes of _D. o.
utahensis_ and the type series of _D. o. panguitchensis_.
_Specimens examined._--Total, 3, all from Utah, distributed as
follows: _Garfield County_: 1 mi. S Panguitch, 6666 ft., 3 (2 RH; 1
UU).
=Dipodomys ordii monoensis= (Grinnell)
_Perodipus monoensis_ Grinnell, Univ. California Publ. Zool.,
21:46, March 29, 1919.
_Dipodomys ordii monoensis_, Grinnell, Journ. Mamm., 2:96, May 2,
1921.
_Type._--Female, adult, no. 27002, Museum of Vertebrate Zoology,
University of California; Pellisier Ranch, 5 mi. N Benton Station,
5600 ft., Mono County, California; obtained on September 21, 1917,
by J. Dixon, original no. 6384.
_Range._--Northeastern Inyo and Mono counties, California, north
to southern Pershing County and east to eastern Nye County,
Nevada; marginal occurrences are: in California, 5 mi. N Benton
Station and Deep Spring Valley; in Nevada, Arlemont, 2 mi. NW
Palmetto, 1 mi. N Beatty, 5 mi. W White Rock Spring, Big Creek at
Quinn Canyon Mts., 2-1/2 mi. S Lock's Ranch, 2 mi. S Millett P.
O., 13-1/2 mi. NW Goldfield, Fingerrock Wash, Eastgate, 1/2 mi. NE
Toulon, 21 mi. W and 2 mi. N Lovelock, 1/2 mi. S Pyramid Lake,
West Walker River in Smith's Valley, and 10 mi. S Yerington.
_Diagnosis._--Size medium (see measurements). Color pale, entire
dorsal surface (_c_) between Pinkish Buff and Cinnamon-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 medium in size;
rostrum relatively long and narrow; nasals relatively short;
interorbital region narrow; interparietal region relatively wide;
lacrimal processes small; auditory bullae relatively small;
pterygoid fossae circular; zygomatic arches robust and relatively
straight; foramen magnum nearly circular.
_Comparisons._--From _Dipodomys ordii columbianus_, _D. o.
monoensis_ differs as follows: Size larger; color lighter; skull
larger; rostrum longer and narrower; interorbital region narrower;
breadth across auditory bullae less; lacrimal processes larger;
braincase less vaulted; auditory bullae more inflated ventrally;
pterygoid fossae smaller; zygomatic arches more robust; cutting
edge of upper incisors wider.
From _Dipodomys ordii fetosus_, _D. o. monoensis_ differs in: Hind
foot shorter; color lighter; skull smaller; rostrum shorter and
narrower; interorbital width less; interparietal region larger;
lacrimal processes smaller; auditory bullae less inflated.
For comparison with _Dipodomys ordii inaquosus_ see account of
that subspecies.
_Remarks._--This subspecies retains all of its diagnostic characters
throughout nearly all parts of its geographic range. Intergradation
occurs in animals from the southern end of Pyramid Lake, Big Smoky
Valley and near Toquima Peak, Nevada; these animals, although typical of
_D. o. monoensis_ in coloration, resemble _D. o. columbianus_ cranially.
Three-way intergradation between _D. o. columbianus_, _D. o. fetosus_
and _D. o. monoensis_ is noted in animals from east-central Nye County,
Nevada. These animals resemble _D. o. monoensis_ in size, _D. o.
fetosus_ in color and resemble _D. o. columbianus_ in certain cranial
features. These animals are referred to _D. o. monoensis_. Animals from
Toulon, Nevada, in the inflation of the auditory bullae, the vault of
the braincase, the color and the total length show intergradation with
_D. o. inaquosus_ but are referable to _D. o. monoensis_.
_Specimens examined._--Total, 264, distributed as follows:
=California=: _Mono County_: Pellisier Ranch, 5 mi. N Benton
Station, 17 (7 DRD; 10 MVZ); Benton, 5639 ft., 2 (1 LACM; 1 MVZ);
Taylor Ranch, 2 mi. S Benton Station, 5300 ft., 2 (MVZ). _Inyo
County_: Deep Springs Valley, 1 (LACM).
=Nevada=: _Washoe County_: 1/2 mi. S Pyramid Lake, 3950 ft., 1
(MVZ); 1-1/2 mi. N Wadsworth, 4100 ft., 2 (MVZ). _Pershing
County_: 21 mi. W and 2 mi. N Lovelock, 4000 ft., 2 (MVZ); 3-1/4
mi. NNE Toulon, 3900 ft., 1 (MVZ); 3 mi. NNE Toulon, 3900 ft., 6
(MVZ); 1/2 mi. NE Toulon, 1 (MVZ); Toulon, 3930 ft., 5 (MVZ).
_Churchill County_: Truckee Canal, 2 mi. SW Hazen, 4000 ft., 1
(MVZ); 1 mi. NW Soda Lake, 4000 ft., 2 (MVZ); 1 mi. S Soda Lake,
4000 ft., 1 (MVZ); 5 mi. W Fallon, 1 (MVZ); 4 mi. W Fallon, 4000
ft., 3 (MVZ); 1 mi. W Mountain Well, 5350 ft., 3 (MVZ); Eastgate,
4400 ft., 13 (MVZ). _Lyon County_: 6 mi. N Fernley, 1 (MVZ); 1 mi.
SE Wadsworth, 4200 ft., 7 (MVZ); 3/4 mi. N Fernley Underpass,
Fernley, 1 (MVZ); 1/2 mi. N Fernley Underpass, Fernley, 1 (MVZ);
Wilson Canyon, 8 mi. NE Wellington, 4700 ft., 1 (MVZ); West Walker
River, Smith's Valley, 4700 ft., 4 (MVZ); 10 mi. S Yerington,
Mason Valley, 4500 ft., 6 (MVZ). _Mineral County_: 8 mi. SE
Schurz, 4100 ft., 18 (MVZ); Fingerrock Wash, Stewart Valley, 5400
ft., 4 (MVZ); Cat Creek, 4 mi. W Hawthorne, 4500 ft., 1 (MVZ);
Huntoon Valley, 5700 ft., 1 (MVZ). _Nye County_: 2 mi. S Millett
P. O., 5500 ft., 1 (MVZ); 4 mi. SE Millett P. O., 5500 ft., 11
(MVZ); 5 mi. SE Millett P. O., 5500 ft., 5 (MVZ); 4 mi. S Millett
P. O., 5500 ft., 2 (MVZ); Millman Ranch, Moore Creek, 6400 ft., 19
mi. SE Millett P. O., 9 (MVZ); Meadow Creek Ranger Station,
Toquima Mts., 2 (MVZ); Monitor Valley, 9 mi. E Toquima Mts., 7000
ft., 19 (MVZ); Fish Spring Valley, 1/2 mi. N Fish Lake, 6500 ft.,
2 (MVZ); Railroad Valley, 2-1/2 mi. S Lock's Ranch, 5000 ft., 5
(MVZ); Hot Creek Valley 3-1/2 mi. E Hot Creek, 5650 ft., 1 (MVZ);
Hot Creek Valley, 4/5 mi. S Hot Creek, 5900 ft., 1 (MVZ); 5-1/2
mi. NE San Antonio, 5700 ft., 1 (MVZ); San Antonio, 5400 ft., 2
(MVZ); 9 mi. W and 3 mi. S Tybo, 6200 ft., 2 (MVZ); Ralston
Valley, 15-1/2 mi. NE Tonopah, 5800 ft., 2 (MVZ); Railroad Valley,
2-1/2 mi. S Lock's Ranch, 5000 ft., 5 (MVZ); Hot Creek Valley
Creek, 5800 ft., 1 (MVZ); Ralston Valley, 34 mi. E and 1 mi. N
Tonopah, 5650 ft., 2 (MVZ); Old Mill, N end Reveille Valley, 6200
ft., 6 (MVZ); 1-1/2 mi. S Silverbow, Kawich Mountains, 1 (MVZ); 5
7/10 mi. SE Kawich, 2 (MVZ); 5 mi. W White Rock Spring, 6950 ft.,
Belted Range, 2 (MVZ); 1 mi. N Beatty, 1 (DRD). _Esmeralda
County_: 13-1/2 mi. NW Goldfield, 4850 ft., 3 (MVZ); 7 mi. N
Arlemont, 5500 ft., 6 (MVZ); Arlemont, 11 (MVZ); Mouth Palmetto
Wash, 7 (DRD); 2 mi. NW Palmetto, 7 (DRD); 1 mi. NW Palmetto, 1
(DRD); Palmetto, 7 (DRD); 1 mi. SE Palmetto, 7 (DRD); Pigeon
Spring, 6400 ft., 1 (MVZ); Indian Spring, Mt. Magruder, 20 (DRD).
=Dipodomys ordii ordii= Woodhouse
_D(ipodomys) ordii_ Woodhouse, Proc. Acad. Nat. Sci. Philadelphia,
6:224, 1853.
_Dipodomys phillipsi ordi_, Coues and Allen, Monogr. North
American Rodentia, p. 541, 1877 (part--the part from El Paso,
Texas).
_Dipodops ordii_, Merriam, N. Amer. Fauna, 4:42, October, 1890
(part--the part from El Paso, Texas).
_Cricetodipus ordii_, Trouessart, Catalogus Mammalium, 1:581,
1897.
_Perodipus ordi_, Elliot, Field Columbian Museum, Zool. Ser.,
2:238, 1901.
_Perodipus montanus richardsoni_, Bailey, N. Amer. Fauna, 25:144,
October, 1905 (part--the part from Carlsbad, New Mexico).
_Perodipus ordii_, Goldman, Proc. Biol. Soc. Washington, 30:113,
May 23, 1917.
_Type._--None designated. Species characterized from specimens
obtained by Dr. Woodhouse at El Paso, Texas.
_Range._--Southeastern Arizona, southern New Mexico, western Texas
and north-central Mexico; marginal occurrences are: in Arizona, 20
mi. NE Calva, Oracle and Calabasas; in Sonora, Nogales; in
Chihuahua, Casas Grandes, Corralitos and Santa Rosalia; in Texas,
16 mi. E Van Horn and 30 mi. N Van Horn; in New Mexico, 40 mi. N
Roswell, 40 mi. SE Corona and Mangos Valley.
_Diagnosis._--Size small (see measurements). Color dark, entire
dorsal surface (16'') between Pinkish Cinnamon and Cinnamon-Buff,
purest on sides and flanks, upper parts suffused with black;
arietiform markings, pinnae of ears, plantar surfaces of hind
feet, dorsal and ventral stripes of tail, brownish-black. Skull of
medium size; rostrum narrow and relatively long; braincase
flattened; auditory bullae but slightly inflated; zygomatic arches
slender and straight; upper incisors short and narrow.
_Comparisons._--From _Dipodomys ordii richardsoni_, _D. o. ordii_
differs as follows: Size smaller; color somewhat lighter; dorsal
and ventral stripes of tail brownish instead of blackish; skull
smaller in all measurements taken.
From _Dipodomys ordii montanus_, _D. o. ordii_ differs in: Size
smaller; color lighter; skull narrower across bullae and rostrum;
wider interorbitally; all other measurements taken the same, thus
imparting to the skull, in dorsal view, a longer, narrower
appearance.
From _Dipodomys ordii chapmani_, _D. o. ordii_ differs in: Size
smaller; color lighter; skull smaller; zygomatic arches narrower
at suture of jugal and zygomatic process of maxillary; rostrum
narrower; upper incisors smaller; nasals shorter; least
interorbital width less.
For comparisons with _Dipodomys ordii sennetti_ and _Dipodomys
ordii compactus_ see accounts of those subspecies.
_Remarks._--Intergradation occurs with _Dipodomys ordii chapmani_,
_Dipodomys ordii longipes_, _Dipodomys ordii medius_ and _Dipodomys
ordii attenuatus_. Only along the Rio Grande near El Paso,
Texas, are individuals of a population uniform. On the periphery of
the range, specimens from a given locality may resemble _D. o. ordii_
or _D. o. longipes_ or may be intermediate between these two subspecies.
Animals from the Organ Mountains near Globe Springs, 20 miles
north of Cliff, New Mexico, and those labeled with reference to Van
Horn, Texas, on the average are darker, have a wider expanse across
the auditory bullae, a wider interorbital region and, in most specimens,
more distally flared nasals than the norm of other populations.
This deviation from the normal is interpreted not as intergradation
with any other subspecies but rather as individual
variation in a given population.
Specimens from 40 miles southeast of Corona and 10 miles northeast
of Socorro, New Mexico, show intergradation between _D. o.
ordii_ and _D. o. montanus_ in size of body, configuration of nasals and
cranial size. For a discussion of intergradation with _D. o. longipes_,
_D. o. medius_ and _D. o. chapmani_ see the remarks in the accounts of
those subspecies.
Specimens from Cananea and Santa Cruz, Sonora, Casas Grandes Viejo,
Chihuahua City and Colonia Diaz, Chihuahua, are not typical of _D. o.
ordii_ but rather show the influence of some race probably to the
southeast that is as yet unknown. In a series of nine specimens from
near Casas Grandes Viejo, Chihuahua, four individuals are typically _D.
o. ordii_, four resemble an apparently undescribed form and one specimen
is intermediate between _D. o. ordii_ and the unnamed subspecies. This
unnamed race differs from _D. o. ordii_ in having darker pelage, darker
dorsal stripe on tail, larger body, wider interorbital region, longer
skull, greater breadth across the bullae, less vaulted braincase, more
robust zygomatic arches and the foramen magnum more deeply notched on
both the dorsal and ventral rims. It seems that these animals mentioned
above should be referred to _D. o. ordii_ at least until such time as
material becomes available from eastern Chihuahua, northern Coahuila and
northeastern Durango.
_Specimens examined._--Total, 451, distributed as follows:
=Arizona=: _Gila County_: Rice, 2 (USBS). _Maricopa County_:
Marinette, 8 (CAS). _Pinal County_: Oracle, 4 (USBS). _Graham
County_: 20 mi. NE Calva, 5 (USBS); Fort Grant, 11 (7 USBS; 4
MVZ). _Pima County_: Ft. Lowell, 3 (DRD); 11-1/2 mi. S Tucson, 1
(MVZ); Continental, 20 (8 USBS; 12 DRD); La Osa, 11 (USNM);
Babiquivari Mountains 10 mi. N International Boundary, 1 (DRD).
_Santa Cruz County_: 2 mi. S Tumacacori Mission, 1 (DRD); 7 mi. N
Patagonia, 4500 ft., 12 (CAS); 3 mi. N Patagonia, 1 (CAS);
Calabasas, 7 (6 USBS; 1 USNM). _Cochise County_: 8 mi. W Bowie, 1
(LACM); Wilcox, 4163 ft., 25 (12 USBS; 5 UM; 4 MVZ; 4 USNM); 12
mi. SE Dos Cabezos, 2 (UM); 1 mi. WSW Chiricahua National
Monument, 5000 ft., 1 (MVZ); Portal, 4500 ft., 2 (USBS); Fairbank,
8 (3 AMNH; 5 CNHM); Mouth Pinery Canyon, 4 (USBS).
=New Mexico=: _Torrance County_: Gran Quivira, Mesa Jumanes, 6
(USBS). _Catron County_: Mangos Valley, 3 (USBS); Alma, 3 (USBS);
Pleasanton, 7 (USBS). _Socorro County_: Gallina Mountains, 1
(USBS); 10 mi. NE Socorro, 2 (USBS); 3 mi. N Socorro, 3 (MVZ);
Socorro, 1 (USBS); Range, 2 mi. SW Socorro, 4700 ft., 2 (MVZ);
Lava Mesa; S Clyde, 4300 ft., 1 (MVZ); Dry Creek, 3 (USBS); San
Augustine Plain, 12 mi. N Monica Springs, 2 (USBS). _Lincoln
County_: Guyo Canyon, 40 mi. SE Corona, 1 (USBS); 4 mi. W
Carrizozo, 2 (UM). _Grant County_: Gila, 5 (USBS); Cactus Flat, 20
mi. N Cliff, 3 (USBS); Cliff, Gila River, 4470 ft., 1 (USBS);
Silver City, 2 (USBS); Redrock, 2 (USBS); 9 mi. N Faywood, 2
(USBS); Hachita, 1 (USBS); Dog Spring, 11 (USNM); Deer Creek,
Culberson Ranch, 2 (USBS). _Sierra County_: Fairview, 6500 ft., 1
(USBS); Cuchillo, 4700 ft., 3 (USBS); Lake Valley, 5000 ft., 3
(USBS). _Otero County_: Tularosa, 5 (USBS); 10 mi. SW Tularosa, 2
(CNHM); Quartz Sands, SW Tularosa, 2 (MVZ); White Sands, 12 mi. W
Alamogordo, 1 (MVZ); 2 mi. S Alamogordo, 2 (UM); 3 mi. S
Alamogordo, 1 (UM); 5 mi. S Alamogordo, 1 (UM); 9 mi. SW
Alamogordo, 1 (UM); 12 mi. SW Alamogordo, 2 (UM); 15 mi. SW
Alamogordo, 1 (LACM); White Sands, 18 mi. SW Alamogordo, 7 (MVZ);
19 mi. SW Alamogordo, 3 (UM); White Sands National Monument, 24
(13 CNHM; 11 LACM); 1/2 mi. SW Escondido, 4000 ft., 2 (MVZ);
Jarilla, 1 (USBS). _Hidalgo County_: 10 mi. NW Lordsburg, 6
(LACM); 4 mi. NW San Luis Pass, 5200 ft., Animas Valley, 5 (MVZ).
_Luna County_: Deming, 11 (USBS). _Dona Ana County_: Garfield, 4
(USBS); 6 to 8 mi. NE Las Cruces, 1 (CAS); 15 mi. W Las Cruces, 1
(LACM); 11 mi. W Las Cruces, 2 (CAS); Las Cruces, 3 (USBS); Organ
Mountains, near Globe Springs, 2 (USBS); Coe's Ranch, El Paso
Road, 35 mi. N El Paso, Texas, 2 (USBS); 1/4 mi. N Strauss, 2
(CAS); 1 mi. E Strauss, 4100 ft., 7 (MVZ); 35 mi. W El Paso,
Texas, 2 (USNM); 20 mi. W El Paso, Texas, 1 (USNM); 10 mi. W El
Paso, Texas, 1 (USNM); Mexican Boundary, near monument 5, Lat. 31°
47'; Long. 30° 15', 13 (USNM). _Eddy County_: 3 mi. NW Carlsbad, 7
(MVZ); 2 mi. E Carlsbad, 1 (KU); Eddy, 10 (USBS).
=Texas=: _El Paso County_: 3 mi. NE City Limits, El Paso, 3764
ft., 15 (12 MVZ; 3 TCWC); El Paso, 3 (USBS); near El Paso, 7
(USNM). _Hudspeth County_: 1 mi. NW old Fort Hancock, 3900 ft., 3
(MVZ); Fort Hancock, 4 (USNM); 4 mi. NW Sierra Blanca, 1 (LACM).
_Culberson County_: 35 mi. N Van Horn, 5 (TCWC); 30 mi. N Van
Horn, 1 (TCWC); 16 mi. E Van Horn, 3 (TCWC); 16 mi. SE Van Horn, 5
(TCWC); Kent, 1 (USBS). _Reeves County_: 5 mi. E Toyahvale, 1
(USBS). _Jeff Davis County_: 14-1/2 mi. S Fort Davis, 2 (UM).
_Presidio County_: 10 mi. NE Marfa, 1 (UM).
=Sonora=: Nogales, 2 (USNM); Santa Cruz, 4 (USNM); 5 mi. N
Cananea, 4750 ft., 4 (MVZ); Alamo Wash, 35 mi. NW Magdalena, 5
(DRD); Sonora, 2 (AMNH).
=Chihuahua=: 4.3 mi. W Casas Grandes Viejo, 5000 ft., 8 (MVZ); 1.5
mi. W Casas Grandes Viejo, 1 (MVZ); Casas Grandes, 2 (USBS);
Gallego, 1 (USBS); Colonia Diaz, 6 (USBS); Las Trincheras, 9 mi. S
by road Boquillos de Condios, 4 (MVZ); Santa Rosalia, 6 (USBS);
Chihuahua, 7 (USBS); 5 mi. SE Chihuahua, 5250 ft., 4 (MVZ);
Corallitos, 4 (1 USBS; 3 MVZ).
=Dipodomys ordii luteolus= (Goldman)
_Perodipus ordii luteolus_ Goldman, Proc. Biol. Soc. Washington,
30:112, May 23, 1917.
_Dipodomys phillipsi ordi_, Coues and Allen, Monogr. of N. Amer.
Rodentia, p. 541, August, 1877 (part--the part from Niobrara
River, Nebraska).
_Perodipus montanus richardsoni_, Cary, N. Amer. Fauna, 33:141,
August 17, 1911 (part--the part from Sterling, Colorado).
_Dipodomys ordii luteolus_, Grinnell, Journ. Mamm., 2:96, May 2,
1921.
_Type._--Male, adult, no. 160408, U. S. Nat. Mus. Biol. Surv.
Coll.; Casper, Natrona County, Wyoming; obtained on September 2,
1909, by Merritt Cary, original no. 1690.
_Range._--Southeastern Wyoming, northeastern Colorado,
northwestern half of Nebraska and southwestern South Dakota;
marginal occurrences are: in Wyoming, Casper, Sun and Ft. Steele;
in Colorado, Loveland, Hugo and Akron; in Nebraska, Birdwood
Creek, Neligh and Valentine; in South Dakota, Batesland and
Buffalo Gap.
_Diagnosis._--Size medium (see measurements). Color light, entire
dorsal surface between Light Ochraceous-Buff and Ochraceous-Buff,
purest on sides and flanks; upper parts but lightly washed with
black; arietiform markings, plantar surfaces of hind feet, pinnae
of ears and dorsal and ventral stripes of tail, blackish. Skull
medium in size; jugal weak; braincase slightly inflated; nasals
slightly flared distally.
_Comparisons._--From _Dipodomys ordii terrosus_, _D. o. luteolus_
differs as follows: Size smaller, except that tail and ear are
longer; color lighter in all pigmented areas; skull smaller in
every measurement taken; auditory bullae less inflated; zygomatic
processes of maxillae smaller; cutting edge of upper incisors
narrower; zygomatic arch weaker.
From _Dipodomys ordii priscus_, _D. o. luteolus_ differs in: Size
larger except hind foot which is shorter; dorsal and ventral
stripes of tail, plantar surfaces of hind feet, arietiform
markings and pinnae of ears, in most specimens, darker; auditory
bullae less inflated; nasals shorter; rostrum wider; total length
of skull shorter; zygomatic arch weaker; foramen magnum more
ovate.
From _Dipodomys ordii evexus_, _D. o. luteolus_ differs as
follows: Hind foot longer; color lighter in all pigmented areas;
auditory bullae more inflated; pterygoid fossae more expanded
laterally; width across maxillary arches less; interorbital region
narrower; zygomatic arch weaker; external auditory meatus almost
round as opposed to ovoid.
Comparison with _Dipodomys ordii richardsoni_ is made in account
of that subspecies.
_Remarks._--_Dipodomys ordii luteolus_ resembles _D. o. priscus_ in
size and color but can readily be told from it and _D. o. richardsoni_
when specimens from the central portions of the ranges of the subspecies
are compared. At and near the periphery of the range, especially
in that part which adjoins the range of _D. o. richardsoni_,
intergradation occurs. Specimens from Kennedy, Perch and Neligh,
Nebraska, approach _D. o. richardsoni_ in the shape of the pterygoid
fossae and nasal bones, but in all other characters they resemble
_D. o. luteolus_ to which subspecies they are here referred. Specimens
from Loveland and 20 miles east of Avalo, Colorado, show intergradation
with _D. o. richardsoni_ in the width of the rostrum and size of the
zygomatic arch but are referable to _D. o. luteolus_.
No specimens here referred to _D. o. luteolus_ were found to intergrade
with _D. o. priscus_.
_Specimens examined._--Total, 250, distributed as follows:
=South Dakota=: _Perkins County_: 9 mi. N Bison, 8 (MVZ). _Meade
County_: Smithsville, 2 (USBS). _Jackson County_: 20 mi. SSE
Phillip, in Haakon County, 1 (MVZ). _Custer County_: Elk Mountain,
1 (MHS); Buffalo Gap, 2 (USNM). _Bennett County_: Big Spring
Canyon, Batesland, 7 (CNHM); Rosebud Indian Agency, 1 (USBS).
=Wyoming=: _Fremont County_: 2-1/2 mi. W Shoshoni, 80 (KU);
Granite Mountain, 1 (UM). _Natrona County_: 1 mi. NE Casper, 19
(KU); Casper, 7 (USBS); Sun, 8 (USBS). _Converse County_: Douglas,
2 (USBS). _Niobrara County_: Van Tassel Creek, 1 (CM). _Carbon
County_: Fort Steele, 1 (USBS). _Goshen County_: Rawhide Butte, 1
(USBS).
=Nebraska=: _Sioux County_: Warbonnet Canyon, 6 (MHS); Glen, 1
(MHS); Agate, 3 (1 UM; 2 CNHM); Jim Creek, 1 (MHS). _Box Butte
County_: 16 mi. NE Alliance, 4 (UM). _Sheridan County_: 12 mi. S
Gordon, 3 (MVZ); 5 mi. N Antioch, 4 (UM); 4 mi. N Antioch, 3 (UM).
_Cherry County_: Valentine, 9 (6 USBS; 2 USNM; 1 NU); 15 mi. E
Gordon, 1 (CNHM); Niobrara River, 3 (USBS); 18 mi. NW Kennedy, 3
(2 USBS; 1 MHS); Valentine Lake Refuge, 1 (NU); Kennedy, 10 (3
MVZ; 5 USBS; 2 USNM); 30 mi. S Wood Lake, 4 (CNHM); Cherry, 7
(NU); near Clark's Canyon, 7 (USBS). _Rock County_: Perch, 12 (10
AMNH; 2 CNHM). _Antelope County_: Neligh, 8 (1 USBS; 7 MHS).
_Scotts Bluff County_: Mitchell, 1 (MHS). _Hooker County_: Kelso,
5 (UM). _Thomas County_: Halsey, 1 (MHS); Dismal River, 2 (USBS).
_Custer County_: 1 mi. NW Gavin, 6 (2 MVZ; 4 UM); Gavin, 3 (UM); 8
mi. NW Anselmo, 1 (UM); 7 mi. NW Anselmo, 1 (UM). _Lincoln
County_: Birdwood Creek, 2 (USBS); Brady, 4 (NU); Hackberry Lake,
13 (UM).
=Colorado=: _Larimer County_: Loveland, 8 (USBS). _Weld County_:
20 mi. E Avalo, 3 (USBS); 8 mi. E Pawnee Buttes, 1 (USBS);
Greeley, 1 (USBS). _Morgan County_: 30 mi. S Fort Morgan, 1 (UM).
_Logan County_: Sterling, 8 (USBS). _Adams County_: Barr Lake, 4
(CMNH); 6 mi. E and 1 mi. N Denver, 1 (CMNH); 3 mi. NE Fitzsimons,
1 (CMNH). _Washington County_: Akron, 2 (UM). _Lincoln County_:
Limon, 1 (USBS); Hugo, 1 (USBS). _El Paso County_: Colorado
Springs, 2 (MVZ).
=Dipodomys ordii extractus= new subspecies
_Type._--Male, adult, no. 76562, Museum of Vertebrate Zoology,
University of California; 1 mi. E Samalayuca, 4500 ft., Chihuahua,
Mexico; obtained on May 15, 1937, by William B. Richardson,
original no. 2148.
_Range._--Known only from the type locality.
_Diagnosis._--Size medium (see measurements). Color pale, entire
dorsal surface Pinkish Buff, purest on sides and flanks, dorsal
surface but slightly suffused with black; pinnae of ears, plantar
surfaces of hind feet, dorsal and ventral stripes of tail
light-brownish. Skull medium in size; nasals long; rostrum
relatively as well as actually wide; least interorbital breadth
wide; auditory bullae relatively little inflated; braincase but
slightly vaulted; external auditory meatus ovoid; zygomatic arches
relatively robust and but slightly bowed laterad; pterygoid fossae
subcircular; lacrimal processes small; foramen magnum deeply
notched on dorsal border.
_Comparisons._--From _Dipodomys ordii ordii_, _D. o. extractus_
differs as follows: Size larger; color lighter; arietiform marks
absent in _D. o. extractus_ but pronounced in _D. o. ordii_; skull
larger; rostrum wider; nasals longer; re inflated laterally;
braincase less vaulted; pterygoid fossae subcircular as opposed to
circular; foramen magnum more deeply evaginated dorsally and
ventrally.
[Illustration: FIG. 25. Known occurrences and probable geographic range
of the subspecies of _Dipodomys ordii_ in the northeastern fourth of the
range of the species.
1. _D. o. richardsoni_ 8. _D. o. terrosus_ 18. _D. o. montanus_
2. _D. o. oklahomae_ 10. _D. o. uintensis_ 24. _D. o. priscus_
5. _D. o. evexus_ 11. _D. o. sanrafaeli_ 31. _D. o. longipes_
6. _D. o. medius_ 15. _D. o. luteolus_ 33. _D. o. nexilis_ ]
From _Dipodomys ordii obscurus_, _D. o. extractus_ differs as
follows: Size larger; color lighter; skull larger in all respects,
notably in least interorbital width, greatest length of skull and
breadth across auditory bullae; zygomatic arches less robust and
straight as opposed to robust and bowed laterally; pterygoid fossae
subcircular as opposed to circular; auditory bullae more inflated
ventrally.
From _Dipodomys ordii idoneus_, _D. o. extractus_ differs in: Size
larger; color lighter; skull larger in all measurements taken
except least interorbital width and breadth across maxillary
arches which are smaller; nasals longer and narrower; braincase
less vaulted; zygomatic arches less robust and more nearly
straight; auditory bullae less inflated ventrally.
_Remarks._--This subspecies of _Dipodomys ordii_ is the palest of
any of the known races from Mexico. It inhabits an area of light-colored
sandy soil at the type locality.
The only subspecies with which _D. o. extractus_ really needs comparison
is _Dipodomys ordii ordii_ from which it differs as described above. The
series which is herein described contains two individuals that resemble
_D. o. ordii_ cranially and three that resemble it in color although
they are somewhat paler. One specimen, MVZ no. 76560, is the palest of
any of the series, has a short tail and in these respects resembles the
pale form of _Dipodomys ordii compactus_. It is apparent from the skull
of this latter individual that it is not _D. o. compactus_ but _D. o.
extractus_.
_Dipodomys ordii ordii_ inhabits, in most of its range, dark-colored
soils, whereas _D. o. extractus_ inhabits light-colored soils. Possibly
the differentiation that has occurred is a result of an ecological
separation much as occurs with _Perognathus_ on the white sands and
black lavas of the Tularosa Basin of New Mexico (see Benson,
1933).
_Specimens examined._--Total, 14, all from Chihuahua, as follows: 1
mi. E Samalayuca, 4500 ft., 14 (MVZ).
=Dipodomys ordii chapmani= Mearns
_Dipodomys chapmani_ Mearns, Bull. Amer. Mus. Nat. Hist., 2:291,
February 21, 1890.
_Cricetodipus chapmani_, Trouessart, Catalogus Mammalium, 1:581,
1897.
_Perodipus chapmani_, Elliot, Field Columbian Museum, Zool. Ser.,
2:237, 1901.
_Perodipus ordii chapmani_, Goldman, Proc. Biol. Soc. Washington,
30:113, May 23, 1917.
_Dipodomys ordii chapmani_, Grinnell, Journ. Mamm., 2:96, May 2,
1921.
_Cotypes._--Male, no. 2400, and female, no. 2398, Amer. Mus. Nat.
Hist.; Fort Verde, Yavapai County, Arizona; obtained on January 26,
1887, and October 1, 1885, respectively, by Edgar A. Mearns. (Type
not seen.)
_Range._--Central Arizona from the Grand Canyon of the Colorado
River, southeastward to, and probably beyond, Fort Verde; marginal
occurrences are: lower end Prespect Valley, Kirkland, Prescott,
Camp Verde, Bill Williams Mountain.
_Diagnosis._--Size medium (see measurements). Color dark; entire
dorsal surface between (_10''_) Pinkish Cinnamon and
Cinnamon-Buff, purest on sides and flanks, upper parts strongly
suffused with black; arietiform markings, pinnae of ears, plantar
surfaces of hind feet, dorsal and ventral stripes of tail,
blackish. Skull medium in size; rostrum long and narrow; nasals
long; auditory bullae slightly distended; braincase vaulted.
_Comparisons._--For comparisons with _Dipodomys ordii cupidineus_,
_Dipodomys ordii longipes_ and _Dipodomys ordii ordii_ see
accounts of those subspecies.
_Remarks._--This subspecies of _Dipodomys ordii_ is relatively isolated
from other subspecies of the species. The Colorado River with its deep
canyons is interposed between the ranges of _D. o. chapmani_ and _D. o.
cupidineus_. A high range of mountains separates _D. o. chapmani_ from
the range of _D. o. longipes_. The only race with which _D. o. chapmani_
probably comes into contact is _D. o. ordii_ to the southeast. No
specimens are available from the southeastern part of the range of _D.
o. chapmani_. Animals from the northwestern part of the range of _D. o.
ordii_, without exception, have dark-colored pelage which is
characteristic of _D. o. chapmani_. In the shape of the nasals, vault of
the braincase, interorbital width and auditory bullae, animals from
Rice, Arizona, resemble _D. o. chapmani_, but in other characters
resemble _D. o. ordii_ to which subspecies they are referred. Animals
from 20 miles northeast of Calva, Arizona, are dark-colored and are
intermediate between the dark _D. o. chapmani_ and the pale _D. o.
ordii_ in size of the cranium and body but are referable to _D. o.
ordii_. In the northwestern part of the range of _D. o. chapmani_ the
animals are not typical in that they have a shorter, wider rostrum and a
heavier zygomatic arch than topotypes.
_Specimens examined._--Total, 90, all from Arizona, distributed as
follows: _Mohave County_: lower end Prospect Valley, 4500 ft.,
Grand Canyon, 7 (USBS); Kingman, 9 (LACM). _Coconino County_:
Aubrey Valley, 10 mi. S Pine Spring, 4 (USBS); Bill Williams
Mountain, 1 (USNM). _Yavapai County_: 3 mi. N Fort Whipple, 11
(USBS); Fort Whipple, 4 (2 USBS; 2 USNM); Willow Creek, 4 mi. N
Prescott, 4 (MVZ); 1 mi. W Camp Verde, 1 (MVZ); Camp Verde, 33 (15
USBS; 3 MVZ; 3 AMNH; 9 LACM; 3 DRD); 1/2 mi. S Camp Verde, 4 (MVZ);
Kirkland, 9 (USBS); Turkey Creek, 3 (USBS).
=Dipodomys ordii montanus= Baird
_Dipodomys montanus_ Baird, Proc. Acad. Nat. Sci. Philadelphia,
7:334, April, 1855.
_Perodipus montanus_, Merriam, Proc. Biol. Soc. Washington,
17:140, July 14, 1904.
_Perodipus ordii montanus_, Goldman, Proc. Biol. Soc. Washington,
30:113, May 23, 1917.
_Dipodomys ordii montanus_, Grinnell, Journ. Mamm., 2:96, May 2,
1921.
_Type._--Male, no. 490/1631, U. S. Nat. Mus.; near Fort
Massachusetts, Costilla County, Colorado; obtained in 1853 by F.
Kreutzfeldt (Pacific Railroad Survey).
_Range._--The San Luis Valley of south-central Colorado and
north-central New Mexico; marginal occurrence are: in Colorado, 22
mi. E Mosca, Saguache, Alamosa and Antonito; in New Mexico, 4 mi.
SW Cimmaron.
_Diagnosis._--Size small (see measurements). Color dark, entire
dorsal surface between (_c_) Vinaceous-Buff and Avellaneous,
purest on sides and flanks, upper parts strongly suffused with
black; arietiform markings, pinnae of ears, plantar surfaces of
hind feet and dorsal and ventral stripes of tail, blackish. Skull
small; rostrum slender; interorbital width narrow; auditory bullae
strongly inflated; braincase but slightly vaulted; interparietal
region wide; zygomatic arch bowed laterally.
_Comparisons._--From _Dipodomys ordii richardsoni_, _D. o.
montanus_ differs as follows: Size smaller; color darker in all
pigmented areas; ventral stripe of tail continuous to end of
pencil in all specimens, whereas in _D. o. richardsoni_ the stripe
is incomplete in most specimens. In all specimens the dorsal and
ventral stripes of the tail are darker in _D. o. montanus_; skull
smaller in all measurements taken; jugal straight or nearly so, as
contrasted to bowed laterally; pterygoid fossae shallower and more
ovoid, that is to say, wings of pterygoid flare laterally; ventral
projection of auditory bullae more pronounced; rostrum,
immediately in front of zygomatic process of maxilla, nearly
parallel to median plane along long axis of skull, while in _D. o.
richardsoni_ this union forms a decided obtuse angle; paroccipital
processes smaller; foramen magnum smaller and more ovoid as
opposed to larger and more circular.
From _Dipodomys ordii evexus_, _D. o. montanus_ differs as
follows: Size smaller in all measurements taken except width
across auditory bullae which is greater; color darker, ventral
stripe of tail continuous to end of pencil; least width of
supraoccipital less (2.5 mm. in _D. o. montanus_ and 3.5 mm. in
_D. o. evexus_); extension of premaxillae posterior to nasals
greater; braincase more inflated dorsally; bullae relatively as
well as actually larger and more inflated ventrally; pterygoid
fossae narrower anteroposteriorly and wider laterally than in _D.
o. evexus_; jugal straight or nearly so as contrasted to bowed
laterally; lacrimal processes smaller.
For comparison with _Dipodomys ordii medius_ see account of that
subspecies.
[Illustration: FIG. 26. Known occurrences and probable geographic range
of the subspecies of _Dipodomys ordii_ in the southwestern fourth of the
range of the species.