Long-tailed Weasel
Plates 16, 17, 18, 31, 32 and 33
Putorius Noveboracensis Emmons, Quadrupeds of Massachusetts, p. 45, 1840.
Mustela fusca DeKay, Zool. of New York, Pt. 1, Mammalia, p. 34, 1842.
Putorius fuscus Audubon and Bachman, Journ. Acad. Nat. Sci. Philadelphia, 8 (Pt. 2):288, 1842; Audubon and Bachman, Vivip. quadrupeds of N. Amer., 3:234, pl. 148, 1853 (pl. 1848).
Putorius noveboracensis, DeKay, Zool. of New York, Pt. 1, Mammalia, p. 34, 1842; Baird, Mamm. N. Amer., p. 166, 1858; Merriam, N. Amer. Fauna, 11:16, pl. 4, figs. 1, 1a, 2, 2a, pl. 5, figs. 3, 3a, text figs. 4-6, 30, June 30, 1896; Bangs, Proc. Biol. Soc. Washington, 10:13, pl. 1, figs. 2, 2a, pl. 2, figs. 2, 2a, and pl. 3, figs. 3, 3a, February 25, 1896; Cory, Mamm. Illinois and Wisconsin, p. 366, plates, 1912.
Putorius erminea, Audubon and Bachman, Vivip. quadrupeds of N. Amer., 2:56, pl. 59, 1851.
Putorius agilis Audubon and Bachman, Vivip. quadrupeds of N. Amer., 3:184, pl. 140, 1853.
Putorius richardsonii, Baird, Mamm. N. Amer., p. 164, 1858 (part).
Putorius (Gale) erminea, Coues, Fur-bearing animals, p. 109, 1877 (part).
Putorius noveboracensis notius Bangs, Proc. New England Zool. Club, 1:53, June 9, 1899. Type from Weaverville, Buncombe County, North Carolina.
Mustela noveboracensis noveboracensis, Miller, U. S. Nat. Mus. Bull., 79:97, December 12, 1912; Soper, Journ. Mamm., 4:251, November 1, 1923.
Mustela cicognanii, Henninger, Journ. Mamm., 2:239, November 29, 1921; Seton, Lives of game animals, 2:584, 1929 (part, Ohio); Hamilton, Amer. Midland Nat., 14:290, July, 1933 (part, Ohio); Lyon, Amer. Midland Nat., 17:109, January, 1936 (part, Ohio).
Mustela noveboracensis, Jackson, Journ. Mamm., 3:15, February 8, 1922.
Mustela frenata noveboracensis, Hall, Carnegie Instit. Washington Publ., 473:104, November 20, 1936; Hall, Amer. Midland Nat., 18:304, March, 1937.
Type.—Williamstown, Berkshire County, Massachusetts. Type specimen not known to be in existence.
Range.—Altitudinally, sea level to highest parts of mountains of eastern United States; Canadian Life-zone of Ontario and Quebec southward through eastern United States in Canadian, Transition and Upper Austral life-zones to and including upper edge of Lower Austral Life-zone in the Carolinas and northern parts of Georgia, Alabama, and Mississippi; westward from the Atlantic Coast to St. Croix and Mississippi rivers. See figure [29] on page [221].
Characters for ready recognition.—Differs: From M. f. olivacea, in males, by width of tympanic bulla which is less than rather than more than 8.5 mm., and in adult females by total length which is less than rather than more than 345 mm. and by mastoid breadth which is less than rather than more than distance between articular faces of exoccipital condyle and glenoid fossa; from M. f. occisor by a number of average differences including smaller size, relatively shorter tail and relatively narrower skull (see measurements); from M. f. spadix by least width of color of underparts amounting to less than 41 per cent of greatest width of color of upper parts, absence of color of underparts on ankles and feet, adults with hind foot less than 50 in males and 40 in females, orbitonasal length less than 15.5 in males and 13.5 in females, length of tooth-rows less than 18.0 in males and 15.7 in females, mastoid breadth less than 25.5 in males and 22.0 in females; from M. f. primulina in males by interorbital breadth averaging more than 24 per cent of basilar length, orbitonasal length averaging more than 34 per cent of basilar length or 64 per cent of mastoid breadth, tympanic bullae less inflated anteromedially, than posteromedially, and in females by orbitonasal length amounting to more than two-thirds of mastoid breadth, by zygomatic breadth averaging less than 21, and by anterolateral margin of tympanic bullae not projecting below squamosal; from M. f. arthuri in males, by zygomatic breadth more than distance between anterior palatine foramen and anterior margin of tympanic bulla and by convex dorsal outline of skull in longitudinal axis.
Description.—Size.—Male and Female:
| Locality | Number of specimens averaged | Total length | Length of tail | Per cent of body- length | Length of hind foot |
| Massachusetts | 8 ad. ♂ | 415 (390-432) | 146 (127-159) | 54% | 46.0 (41.0-48.0) |
| 4 ad. ♀ | 311 (298-321) | 104 (95-114) | 50% | 33.9 (31.5-37.0) | |
| Liberty Hill, Conn. | 10 ad. ♂ | 411 (379-438) | 141 (124-155) | 52% | 47.1 (43.0-51.5) |
| 6 ad. and sad. ♀ | 318 (303-338) | 105 (80-123) | 49% | 33.0 (31.7-36.0) | |
| Beaver Dam, Wisc. | 10 ad. ♂ | 407 (372-431) | 130 (113-143) | 47% | 46.0 (42.0-50.0) |
| 4 ad. ♀ | 326 (303-338) | 99 (86-108) | 43% | 35.6 (34.6-38.0) | |
| Washtenaw Co., Mich. | 10 ad. ♂ | 371 (350-405) | 130 (115-140) | 54% | 45.0 (40.0-50.0) |
| 10 ad. ♀ | 306 (290-335) | 97 (90-120) | 46% | 34.0 (30.0-40.0) |
The length of the hind foot averages more than the basal length in males whereas the reverse is true in females. The tail, relative to the length of the body, is longer in males than in females. The average differences in external measurements of the two sexes in Massachusetts, are: total length, 104; length of tail, 42; length of hind foot, 12.1. In Michigan, where the males are smaller, corresponding differences are only, 65, 33, and 11. Weight of 19 adult males from New York (Hamilton, 1933:294), 225 (196-267) grams and in 13 adult females, 102 (72-126) grams. Weights of 2 adults from Michigan are: ♂ 258; ♀ 101 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 as shown in figure [19].
Color.—Upper parts, in summer, Vandyke Brown or darker than tone 4 of Burnt Umber of Oberthür and Dauthenay, pl. 304. Sometimes approaching tone 2 of Warm Sepia of Oberthür and Dauthenay, pl. 305. Underparts, in summer, ranging from white through Napthalene Yellow (Peterboro, N. Y.), Pale Orange Yellow (eastern Mass.), near Primuline Yellow (unusual specimen from Leelanau Co., Mich.) to near (c) Deep Chrome (no. 19053, U. S. Nat. Mus., Roan Mts., N. C.) In winter, all white except tip of tail, or upper parts near (12" 1) Rood's Brown and tone 2 of Raw Umber of Oberthür and Dauthenay, pl. 301, with underparts white or sometimes tinged with yellowish. Tip of tail at all times black. Upper parts of uniform color except for occasional slight darkening of nose. Color of underparts extends distally on posterior sides of forelegs to foot and sometimes over upper sides of toes and on medial sides of hind limbs only to knees. Least width of color of underparts averaging, in a series of twenty-two males, mostly in full winter pelage, from Liberty Hill, Connecticut, 21 (11-40) per cent of greatest width of color of underparts. In eleven females from the same place, corresponding percentages are 20 (14-29). Black tip of tail in same series of males, most of which are in full winter pelage, 70 (60-75) mm. long; thus longer than hind foot and averaging 50 per cent of length of tail-vertebrae.
Skull and teeth.—Male (based on ten adults from Massachusetts): See measurements and plates [16]-[18]; weight, 3.6 (3.3-4.4) grams; basilar length, 44.6 (43.3-46.0); zygomatic breadth less than distance between condylar foramen and M1 or than between anterior palatine foramen and anterior margin of tympanic bulla; mastoid breadth less than postpalatal length; postorbital breadth more or less than length of upper premolars and greater than width of basioccipital measured from medial margin of one foramen lacerum posterior to its opposite; interorbital breadth more or less (usually more) 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 length of P4; anterior margin of tympanic bulla as far posterior to foramen ovale as width of 3 to 6 upper incisors; height of tympanic bulla more or less 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 behind or directly below posterior fourth of m1.
Female (based on five adults from Mass.): See measurements and plates [31]-[33]; weight, 1.7 (1.2-2.1) grams; basilar length, 36.5 (35.2-38.1); zygomatic breadth less than distance between condylar foramen and M1 or than between anterior palatine foramen and anterior margin of tympanic bulla; postorbital breadth more or less than length of upper premolars and more than width of basioccipital measured from medial margin of one foramen lacerum posterior to its opposite; least width of palate more or less (usually less) than greatest length of P4; tympanic bulla as far posterior to foramen ovale as width of 4 to 5-1/2 upper incisors; height of tympanic bulla less 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 than rostrum.
The skull of the female averages 53 per cent lighter than that of the average male.
Comparisons of the skull with those of M. f. olivacea, M. f. spadix, M. f. primulina, and M. f. arthuri, are made in the accounts of those subspecies. As compared with that of M. f. occisor the skull of adult male noveboracensis, is of smaller average size with relatively (to basilar length of Hensel) lesser mastoid and zygomatic breadths. In addition to the zygomatic arches of noveboracensis being less widely bowed outward they seem to be more rounded posteriorly. Comparisons of subadult females indicate that these differences exist in the females as well as in the adult males.
Remarks.—The earliest of the post-Linnaean references to this weasel mostly were under the specific name erminea in the belief that the American animal was the same as the larger of the two common species of weasel in the Old World. The name noveboracensis, now in use for this subspecies, was applied in 1840 and since that time the males usually have borne that name; the females, because they are smaller, were more frequently confused with some other species. Audubon and Bachman in 1853 even proposed the name agilis for the female in the mistaken belief that it was a species distinct from the male. After 1896, when Bangs correctly classified the weasels of the eastern United States, the males have been correctly identified and the females, except by a few authors, likewise have been correctly named. Because many early American naturalists did their first collecting of mammals in the geographic range of noveboracensis, the person who examines labels of specimens of this subspecies can find data written in the hand of Spencer Fullerton Baird, Theodore Roosevelt, and other naturalists famous for their work as scientists or accomplishments otherwise. The material is more nearly adequate than is that of many other subspecies and the number of specimens is exceeded—and only slightly—by that of the subspecies nevadensis, which like noveboracensis has a relatively large geographic range.