Part 33
The skull (plates 31-33) is complete and unbroken save for a small puncture in the right squamosal. The incisors above and below and M^2 and P^2 on each side are missing. Four canines are preserved separately. Otherwise the teeth are in place. The skin has been taken down from a mount. Some hair has been lost from in front of the ears. Seven mammae are evident and show the animal to have been nursing young. The slightly faded color was mentioned by Mearns in the original description. He says (1891:234): "The memorandum of the colors was made before skinning, the specimen having been subsequently preserved in a solution of alum and salt, which extracted much of the coloring matter."
_Range._--Transition to Hudsonian life-zones of Arizona and extreme western New Mexico, along the Colorado River, and south of the Little Colorado River, from San Francisco Mountain region along Mogollon Plateau to extreme western New Mexico. See figure 29 on page 221.
_Characters for ready recognition._--Differs from _M. f. neomexicana_ by near (14 _n_) Brussels Brown rather than Buckthorn Brown color of upper parts, in absence rather than presence of white frontal spot continuous with color of underparts, in basilar length of less than 44 in males and 39.3 in females; from _M. f. nevadensis_ in that total length averages less than 375 in males and 330 in females, basilar length averaging less than 41 in males and less than 36.7 in females.
_Description._--_Size._--Male: No. 24679/32071, from Springerville, and no. 248993 from the Kaibab Plateau, measure respectively, as follows: Total length, 363, 367; length of tail, 140, 143; length of hind foot, 41.5, 41.0. Tail is 63, and 64 per cent as long as head and body. These males, the only specimens of that sex of which external measurements are available, probably are grading toward _nevadensis_ and therefore are nontypical.
Female: Three specimens, one young from Little Spring, a subadult from Deadmans Flat and the type specimen, measure respectively as follows: Total length, 323, 296, 302; length of tail, 110, 101, 109; length of hind foot, 38, 33, 36. These average, 307, 107, 36. Tail averages 53 per cent as long as head and body.
Differences in external measurements of the two sexes are: Total length, 56; length of tail, 39; hind foot, 5.5.
_Externals._--Longest facial vibrissae black, brown or white (often all three colors in same specimen) and extending beyond ear; carpal vibrissae same color as underparts and extending to apical pad of fifth digit; hairiness of foot soles (in summer pelage) about as shown in figure 19.
_Color._--Winter pelage unknown. Summer pelage with upper parts near (14 n) Brussels Brown or tone 2 of Raw Umber of Oberthür and Dauthenay, Pl. 301, darker on top of head from nose to line connecting posterior margins of ears. Tip of tail always black. Chin and upper lips white. Remainder of underparts Buff Yellow to Straw Yellow and rarely Ochraceous Buff. Color of underparts extends distally on posterior sides of forelegs over toes onto antipalmar faces of feet and wrists, on medial sides of hind legs to ankles and over antiplantar faces of toes, medial third of tarsus, and over proximal fifth to fourth of ventral side of tail. Least width of color of underparts averaging, in 8 specimens, 44 (29-54) per cent of greatest width of color of upper parts. Black tip of tail, in four females averaging 35 (33-38) mm. long. Thus, averaging shorter than hind foot and 32 per cent of length of tail-vertebrae. Three of the eight specimens before me (no. 242671 from 25 mi. SE Flagstaff, not available at time of this accounting) have the dark spot near the angle of the mouth faintly indicated, whereas the other five lack the spots. The color is as in _M. f. nevadensis_.
_Skull and teeth._--Male (based on 55211, 65231, and 248993; see p. 422): See measurements and plates 19-21; weight 2.7 and 3.1 grams; basilar length, 40.4; zygomatic breadth more than distance between condylar foramen and Ml or than between anterior palatine foramen and anterior margin of tympanic bulla; mastoid breadth more than postpalatal length; postorbital breadth less than length of upper premolars and more than width of basioccipital measured from medial margin of one foramen lacerum posterior to its opposite; interorbital breadth more or less than distance between foramen opticum and anterior margin of tympanic bulla; breadth of rostrum less than length of tympanic bulla; least width of palate more or less than medial length of P4; anterior margin of tympanic bulla as far posterior to foramen ovale as width of 3-1/2 (including I3) upper incisors; height of tympanic bulla more than distance from its anterior margin to foramen ovale; length of tympanic bulla more than length of lower molar-premolar tooth-row and longer or shorter than rostrum; anterior margin of masseteric fossa below talonid of m1.
Female (based on the type specimen): See measurements and plates 31-33; weight, 1.6 grams; basilar length, 35.5; zygomatic breadth less than distance between condylar foramen and M1 and more than distance between anterior palatine foramen and anterior margin of tympanic bulla (nearly equal in each instance); postorbital breadth less than length of upper premolars and greater (7.1-8.4) than width of basioccipital measured from medial margin of one foramen lacerum posterior to its opposite; least width of palate equal to inside length of P4; tympanic bulla as far posterior to foramen ovale as width of 3 (including I3) upper incisors; height of tympanic bulla more than distance from its anterior margin to foramen ovale; length of tympanic bulla more than length of lower molar-premolar tooth-row and greater than length of rostrum.
The skull of the female averages 41 per cent lighter than that of the male.
Compared with the skull of _M. f. nevadensis_, that of _arizonensis_ is smaller, less heavily ridged and has more inflated tympanic bullae and a relatively greater mastoid breadth. Comparison with the skull of _M. f. neomexicana_ is made in the account of that subspecies.
_Remarks._--In 1891 Mearns (234-235) named this weasel as a full species on the basis of two individuals taken by him in 1886 and 1887. Since that time only a few additional specimens have been preserved. Only four are adults. Although this material does not permit of a definition of the subspecies as precise as could be wished, still, it clearly shows that the animals from the plateau region of Arizona are recognizably different from those farther north in the Sierra Nevada of California and those of the Rocky Mountains and Great Basin region northward to the Canadian border. These more northern animals have gone by Mearns' name, _arizonensis_, since the date of its proposal until 1939 when the name _nevadensis_ was proposed.
The smaller size, especially of the skull, and the greater inflation of the tympanic bullae are the outstanding characters which distinguish _arizonensis_ from the similarly marked _nevadensis_. The bullae are relatively much inflated throughout but especially so on the posteromedial parts.
Although the three adult males and two subadult females available of this subspecies are smaller in most parts measured than any of the scores of _nevadensis_ of similar age that have been measured, overlap in size probably will be found as additional specimens of _arizonensis_ become available. A young female, no. 18513, coll. D. R. Dickey, from Little Spring, does have certain cranial measurements as large as are found in the minimum-sized _nevadensis_ from farther north.
Intergradation with the two subspecies whose geographic ranges adjoin that of _arizonensis_ is indicated by specimens at hand. One of these is the adult male from 25 miles southeast of Flagstaff, which shows decided approach to _neomexicana_, in color and in possessing white facial markings less well developed than in _neomexicana_. Even better developed white facial markings, with intervening blackish coloration, are displayed by no. 148271, U. S. Nat. Mus., from 8500 feet altitude on Willow Creek, New Mexico. This subadult female shows approach to _neomexicana_ also in larger size of the skull and entire animal. The great inflation of the posterior part of each of its bullae and the dark color of the upper parts are characters of _arizonensis_. The color of the underparts stops at the ankles leaving the hind feet dark colored, in which respect the specimen is unlike either _neomexicana_ or _arizonensis_. If additional specimens showing the same characters as this one be found at other nearby localities they probably should be given recognition as a separate subspecies. For the present it seems best to regard the specimen merely as an intergrade. Although it might, with almost equal propriety, be referred to either _neomexicana_ or _arizonensis_, the specimen is here placed with the latter. The subadult male from Springerville, Arizona, is of larger size than the topotypical male of _arizonensis_ and in this respect shows slight approach to _nevadensis_. The narrower mastoidal breadth and slightly less inflated tympanic bullae of the male from the Kaibab Plateau may reflect merely individual variation or may represent intergradation in these features with _nevadensis_.
The statement made by Merriam (1896:22) that, "The type specimen . . . is an immature female and is of unusually small size. A male obtained by him [Mearns] near the same place is of the normal size, as is another male in the Department collection from Springerville, Ariz., collected by E. W. Nelson," needs correction. The female is not immature. The specimen obtained by Mearns near the same place probably refers to Amer. Mus. No. 2489, from Quaking Asp Settlement, which lacks both the skull and external measurements. As stuffed it is of small size for a male. The male from Springerville, as shown by the external and cranial measurements, is not of normal (_i. e._ average) size, but is smaller than the average for the other populations of similarly colored weasels referred to by Merriam (_op. cit._) as _arizonensis_ but here described under the name _nevadensis_.
None of the skulls shows signs of infestation of the frontal sinuses by parasites.
_Specimens examined._--Total number, 17, arranged alphabetically by states and from north to south by counties in each state. Unless otherwise indicated specimens are in the collection of the United States National Museum.
=Arizona.= _Coconino County_: VT Park, Kaibab Plateau, 1; Deadman Flat, 6400 ft., 1[74]; Little Spring, 1[59]; Government Prairie, near Parks, 1[74]; _Coconino? County_: San Francisco Forest (Yavapai Co., in 1886), 1[2]; 25 mi. SE Flagstaff, 1; Quaking Asp Settlement, 1[2]. _Apache County_: Springerville, 1; North Fork White River, White Mts., 8200 ft., 4[87]; head San Francisco River, Judd Ranch, Alpine, 1[74]; 2 mi. SE Big Lake Knoll, 8700 ft., 24 mi. S Springerville, 1[74]. _Greenlee County_: S end Blue Range, 9000 ft., Prieto Plateau, 1; Beaver Creek, 7000 ft., 1[74].
=New Mexico.= _Grant County_: Mogollon Mts., Willow Creek, 8500 ft., 1.
=Mustela frenata nevadensis= Hall
Long-tailed Weasel
Plates 19, 20, 21, 33, 34, 35 and 39
_Mustela frenata nevadensis_ Hall, Carnegie Instit. Washington Publ. 473:91, November 20, 1936.
_Putorius longicauda_, Coues, Fur-bearing animals, p. 136, 1877 (part); Merriam, N. Amer. Fauna, 5:83, July 30, 1891.
_Putorius (Gale) brasiliensis frenatus_, Coues, Fur-bearing animals, p. 142, 1877 (part).
_Putorius arizonensis_, Merriam, N. Amer. Fauna, 11:22, figs. 13, 14, June 30, 1896 (part); Stephens, Mammals of California, p. 247, 1906.
_Mustela arizonensis_, Grinnell and Swarth, Univ. California Publ. Zoöl., 10:376, October 31, 1913; Whitlow and Hall, Univ. California Publ. Zoöl., 40:247, September 30, 1933.
_Mustela arizonensis arizonensis_, Grinnell, Univ. California Publ. Zoöl., 40:102, September 26, 1933.
_Mustela frenata_, Boyer, Journ. Mamm., 24:99, February 20, 1943.
_Type._--Female, adult, skull and skin; no. 41053, Mus. Vert. Zoöl.; three miles east Baker, White Pine County, Nevada; May 30, 1929; obtained by E. R. Hall and W. C. Russell; original no. 2674, E. R. H.
The skull (plates 33-35) is complete and unbroken. The teeth all are present and entire. The skin is fairly well made. Eight mammae are evident and show the animal to have been nursing young.
_Range._--Altitudinally, 700 feet at Wenatchee, Washington, to the highest parts of the mountains of the western United States; Upper Sonoran Life-zone to Arctic Alpine Life-zone; southern British Columbia in the Cascades and territory west to Monashee Mountains, and Nelson, southward in the Cascades of northern Washington, over western Washington, Idaho, Utah, and Nevada to northeastern Arizona and northern New Mexico; westward from the eastern base of the Rocky Mountains in Colorado to the western base of the Sierra Nevada and Cascades of California and to the Cascades of southern Oregon. See figures 29 and 30 on pages 221 and 314.
_Characters for ready recognition._--Differs from _M. f. oribasus_ by smaller average size, see measurements; from _M. f. longicauda_ by near (14 _n_ to _l_) Brussels Brown rather than near (_h_) Clay Color of the upper parts, and in males by a shallower occiput in which the depth of the skull, exclusive of the sagittal crest, and taken at the anterior border of the basioccipital, amounts to less than 59 per cent of the mastoid breadth; from _M. f. alleni_ by near (14 _n_ to _l_) Brussels Brown rather than near (_h_) Clay Color of upper parts in summer; from _M. f. neomexicana_ by near (14 _n_ to _l_) Brussels Brown rather than Buckthorn Brown color of upper parts, in absence of white frontal spot continuous with color of underparts, in basilar length of less than 46 in males and 40 in females; from _M. f. arizonensis_ by total length averaging more than 375 in males and 330 in females, basilar length averaging more than 41 in males and 36.7 in females; from _M. f. inyoensis_ by absence of white facial markings; from _M. f. pulchra_ by absence of light facial markings, near (14 _n_ to _l_) Brussels Brown rather than near (16 _j_) Buckthorn Brown color of upper parts, and lesser size, hind foot less than 40 in females and basilar length averaging less than 46.0 in males; from _M. f. xanthogenys_ by absence of light facial markings and near (14 _n_ to _l_) Brussels Brown rather than Buckthorn Brown color of upper parts; from _M. f. munda_ by absence of white facial markings, presence of color of underparts on ventral face of proximal third of tail, and hind foot of less than 50 in males; from _M. f. saturata_ by presence of light color of underparts on tail and ankle and in lesser average breadth across mastoid processes of skull (see measurements); from _M. f. oregonensis_ by absence of nasofrontal white patch, presence of light color of underparts on ventral face of tail, and shorter skull, which, relative to its length in males, is deeper through the braincase; from _M. f. washingtoni_ by presence of light color of underparts on ventral face of tail, by skull which in male relative to basilar length is shorter in the preorbital region and wider across the zygomata and mastoid processes, and in female has longer preorbital region and larger bullae (see measurements); from _M. f. altifrontalis_ by lighter colored upper parts which are tones 1 to 3 of Raw Umber, pl. 301, rather than tone 4 of Brownish Drab, pl. 302, of Oberthür and Dauthenay, by Buff-Yellow to Straw Yellow rather than near (14´ _a_ to 16´ _c_) Ochraceous-Buff color of underparts, by least width of color of underparts amounting to more than 37 per cent of greatest width of color of upper parts, by presence of color of underparts on ventral side of tail and on hind leg over ankle, and by lesser depth of skull through frontal region; from _M. f. effera_ by larger size, males averaging 12-1/2 per cent larger in external measurements, 8 per cent larger in linear measurements of skull, and 22 per cent heavier in weight of skull, total length averaging 400 rather than 360, basilar length averaging 43.6 rather than 40.5.
_Description._--_Size._--Male: Twenty-one adults from the southern half of the Sierra Nevada of California yield average and extreme measurements as follows: Total length, 400 (356-428); length of tail, 150 (125-178); length of hind foot, 46.1 (42-50). Tail averages 60 per cent as long as head and body. Length of hind foot averaging more than basal length. Corresponding measurements of twelve adults from extreme southern and southwestern Colorado are as follows: 407 (355-431); 150 (133-170); 46.0 (42-49).
Female: Ten adults from the Sierra Nevada of California yield average and extreme measurements as follows: Total length, 349 (336-362); length of tail, 127 (120-133); length of hind foot, 36.3 (32-39). Tail averages 57 per cent as long as head and body. Length of hind foot less than basal length. Corresponding measurements of ten adults from the Rocky Mountains of central Colorado are as follows: 347 (325-375); 123 (111-141); 40 (32-43).
The average differences in external measurements of the two sexes, in the Sierras of California are: Total length, 51; length of tail, 23; length of hind foot, 9.8. Weight of 7 adult males from California is 267 (226-345) grams. Two adult females from there weigh 148 and 115 grams and 3 from White Pine County, Nevada, 134, 122 and 124, giving an average of 129 grams.
_Externals._--Longest facial vibrissae black, brown or white (often all three colors in same specimen) and extending beyond ear; carpal vibrissae same color as underparts and extending to apical pad of fifth digit; hairiness of foot-soles (in summer pelage) about as shown in figure 19.
_Color._--Upper parts, in summer, near (14 _n_ to _l_) Brussels Brown or tones 1 to 3 of Raw Umber of Oberthür and Dauthenay, pl. 301, darker on top of head from nose to line connecting posterior margins of ears. Chin and upper lips white. Remainder of underparts Buff-Yellow to Straw Yellow and sometimes Ochraceous-Buff especially in young, and in some adults from southern Colorado. In winter, all white, except tip of tail, or upper parts near (_j_) Snuff Brown or lighter than Brussels Brown with a smoked effect, and underparts white. Tip of tail at all times black. Color of underparts extends distally on posterior sides of forelegs over toes onto antipalmar faces of feet and wrists, on medial sides of hind legs to ankles, over antiplantar faces of toes, medial third of tarsus and usually over proximal tenth to three-fourths of ventral side of tail. Least width of color of underparts averaging, in a series of twenty males from the southern half of the Sierra Nevada of California, 59 (37-76) per cent of greatest width of color of upper parts. In seven males from southern Colorado corresponding percentages are 55 (37-71). Black tip of tail in series from Sierra Nevada averaging 50 (40-60) mm. long; thus longer than hind foot and averaging 33-1/3 per cent of length of tail-vertebrae.
_Skull and teeth._--Male (based on 25 adults, from Sierra Nevada of California): See measurements and plates 19-21; weight, 3.7 (2.9-4.9) grams; basilar length, 43.6 (40.6-46.1); zygomatic breadth more than distance between condylar foramen and M1 (save in four instances) and more than distance between anterior palatine foramen and anterior margin of tympanic bulla (save in two specimens); mastoid breadth more (80 per cent of specimens) or less (20 per cent) than postpalatal length; postorbital breadth less than length of upper premolars and more or less than width of basioccipital measured from medial margin of one foramen lacerum posterior to its opposite; interorbital breadth more or less than distance between foramen opticum and anterior margin of tympanic bulla; breadth of rostrum less than length of tympanic bulla; least width of palate less than medial length of P4 (except in two specimens); anterior margin of tympanic bulla as far posterior to foramen ovale as width of 3 to 5 upper incisors; height of tympanic bulla more than distance from its anterior margin to foramen ovale; length of tympanic bulla more than length of lower molar and premolar tooth-row and longer or shorter than rostrum; anterior margin of masseteric fossa not carried farther forward than point directly below hypoconid of m1.
Female (based on ten adults from Sierra Nevada of California): See measurements and plates 33-35; weight, 2.2 (1.8-2.4) grams; basilar length, 38.2 (36.7-39.5); zygomatic breadth more (except in one specimen) than distance between condylar foramen and M1 and more (save in two specimens) than distance between anterior palatine foramen and anterior margin of tympanic bulla; postorbital breadth less than length of upper premolars and less than (except in one specimen) width of basioccipital measured from medial margin of one foramen lacerum posterior to its opposite; least width of palate more or less than either outside or inside length of P4 but generally less than inside length; tympanic bulla as far posterior to foramen ovale as width of 3 to 5-1/2 upper incisors; height of tympanic bulla more or less (usually more) than distance from its anterior margin to foramen ovale; length of tympanic bulla more than length of lower molar and premolar tooth-row and more or less than length of rostrum.
The skull of the female averages 41 per cent lighter than that of the average male.