Part 17
From _richardsonii_, _haidarum_ differs in that skull of the male is actually larger in its anterior part (breadth of rostrum, interorbital breadth and orbitonasal length) but all measurements of other parts average less. In relation to the basilar length, the tympanic bulla is shorter but all other measurements are more. In the skull of the female, which is 23 per cent heavier, the width of the tympanic bulla and anteroposterior extent of the inner lobe of M1 are the same; in all other measurements the female of _haidarum_ is larger, and in relation to the basilar length all measurements are more except the depth of the skull at the anterior margin of the basioccipital and the width of the tympanic bulla, which are less. By actual weight the skull of the male is 25 per cent lighter and the skull of the female 24 per cent heavier than in _richardsonii_. From _fallenda_ and _anguinae_, _haidarum_ differs in that measurements of the skulls of both sexes either average more, or are uniformly more, with two exceptions. These are the lesser length and breadth of the tympanic bulla, in comparison with males of _fallenda_, and the dimensions of M1 which are about the same in all three races concerned. The pre-and interorbital parts are larger in relation to the remainder of the skull. The postorbital breadth is actually a third more than in _fallenda_. In relation to the basilar length, the tympanic bulla is shorter and the braincase deeper than in males of _anguinae_. The skull of the male is 27 per cent heavier than that of _fallenda_ and 58 per cent heavier than that of _anguinae_. The skull of the female is 59 and 50 per cent heavier than those of _fallenda_ and _anguinae_, respectively. Comparison of the skull with those of _alascensis_, _celenda_ and _seclusa_ has been made in the accounts of those subspecies.
_Remarks._--The available specimens of this ermine were obtained by J. H. Keen in 1898, Wilfred H. Osgood and E. A. Lewis in 1900, W. W. Brown in 1914, J. A. Munro in 1917 and 1918, and Allan Brooks in 1920. _M. e. haidarum_ has more claim to full specific status than any other race of ermine because the diagnostic structural features are numerous and individually of relatively great degree. Indeed, individual variation appears not to bridge the gap between any population of _haidarum_ and other subspecies and strong reasons could be advanced for according _haidarum_ the status of a full species. It differs from the subspecies of _erminea_ on the adjoining mainland and adjoining islands to the north and south and agrees with the Arctic races (_arctica_, _polaris_, _semplei_ and _kadiacensis_) in great extent of the color of the underparts, extension of this color onto the underneath side of the tail, long black tip of the tail and general form of the skull including the relatively heavy preorbital region. The color although darker than in the Arctic subspecies, is lighter than in the insular races immediately to the north and south. In combination, the features mentioned could be taken as indication that _haidarum_ is a relict population from a former glacial period. Assuming that it is a relict population, the color may have become slightly darker since that period but the main response appears to have been a decrease in size for this is a much smaller animal than the Arctic ermines. The size is about what would be expected if one were to judge by the slightly larger ermines on the islands of southeastern Alaska to the north and the smaller ermine on Vancouver Island to the south.
The ermines of the islands of southeastern Alaska, excepting possibly the incompletely known _seclusa_, have fewer characters of the Arctic races and more characters of the races of the adjoining mainland. Therefore, a possible inference is that the distinctive characters of ermines of the Alaskan islands developed with the aid of isolation from stocks which reached the islands after the glacial period. _M. e. haidarum_ may have found its way to the Queen Charlotte Islands in the glacial period.
_Specimens examined._--Total number, 17, as follows. Arranged by locality from north to south. Unless otherwise indicated, specimens are in the U. S. National Museum.
=British Columbia.= Queen Charlotte Islands. Masset, 7 (4[74], 1[2], 1[59]); Skidegate, 1; Graham Island, 5 (2[94], 1[77], 1[2]); Cumsheva Inlet, 3; no locality more definite than Queen Charlotte Islands, 1[2].
=Mustela erminea anguinae= Hall
Ermine
Plates 5, 6, 7, 11, 12 and 13
_Mustela cicognanii anguinae_ Hall, Univ. California Publ. Zoöl., 38:417, November 8, 1932.
_Putorius cicognanii_, Baird, Mamm. N. Amer., p. 161, 1858 (part).
_Putorius streatori_, Swarth, Univ. California Publ. Zoöl., 10:102, February 13, 1912.
_Mustela erminea anguinae_ Hall, Journ. Mamm., 26:79, February 27, 1945; Hall, Journ. Mamm., 26:181, July 19, 1945.
_Type._--Male, adult, complete skeleton (no skin); no. 12482, Mus. Vert. Zoöl., French Creek, Vancouver Island, British Columbia; found as a desiccated carcass on May 1, 1910; obtained by Harry S. Swarth.
_Range._--Vancouver Island, British Columbia. See figures 25, 27 pages 95, 149.
_Characters for ready recognition._--Differs from _M. e. haidarum_, in both sexes, in light-colored underparts less than half the width of dark-colored upper parts, proximal two-thirds of under surface of tail colored like upper parts instead of underparts, interorbital breadth less than distance between glenoid fossa and posterior margin of external auditory meatus; from _M. e. fallenda_, in both sexes, anterior margin of tympanic bullae flush with squamosal rather than projecting from floor of braincase, in males by sagittal crest absent, in females by total length more than 238 and tooth-rows about same length as, instead of longer than, tympanic bulla; from _M. e. streatori_, in male, by sagittal crest absent and hind foot ordinarily more than 33.5, in female by hind foot more than 27.5, basilar length more than 30.2; from _M. e. olympica_, in males, by greater average size, hind foot ordinarily more than 33.4 and interorbital breadth ordinarily more than 8.5, in females by larger size, total length more than 235, tail more than 65, hind foot more than 27.5, basilar length more than 30.2.
_Description._--_Size._--Male: Sixteen adults and subadults yield average and extreme measurements as follows: Total length, 272 (261-284) mm.; length of tail, 81 (74-86); length of hind foot, 35.0 (33.5-36).
Female: Five adults and subadults have corresponding measurements as follows: 247 (241-257); 69 (66-73); 30.0 (28.0-32.0).
_Color._--As described in _Mustela erminea streatori_ except that: occasionally white in winter; upper parts about tone 2 of Dark Chocolate of Oberthür and Dauthenay; least width of color of underparts averaging, in 7 adult males, 6 (0-15) per cent of greatest width of color of upper parts. Black tip of tail in same series averaging 37 (26-46) mm. which is 46 (32-54) per cent of length of tail-vertebrae.
_Skull._--Male (based on 13 adults): See measurements and plates 5-7. As described in _Mustela erminea richardsonii_ except that: Weight, 1.2 (1.0-1.3) grams; basilar length, 34.0 (32.5-35.6); length of tooth-rows more or less (usually less) than length of tympanic bulla.
Female (based on 5 adults): See measurements and plates 11-13. As described in _Mustela erminea richardsonii_ except that: Weight 0.9 (0.77-1.06) grams; basilar length, 31.5 (30.9-31.8) grams; length of tooth-rows more or less than (approximately same as) length of tympanic bulla; breadth of rostrum more than 30 per cent of basilar length.
The sexual dimorphism in the skull is slight, the skull of the male being only a third heavier than that of the female. In _fallenda_ of the adjacent mainland to the east the male is three-fourths heavier than the female. In comparison with _fallenda_, males are smaller, averaging less in every cranial and dental measurement taken and by weight are a fifth lighter; sagittal crest absent rather than present; tympanic bullae flush with squamosal rather than projecting below floor of braincase; in relation to basilar length, tympanic bullae smaller, braincase deeper and broader, skull wider interorbitally and across zygomata. Females are larger than in _fallenda_, and with one exception average larger in every cranial and dental measurement taken, being 6 per cent heavier. The one exception mentioned is the lesser actual length of the tympanic bulla in _anguinae_, in which the length of the tooth-rows is about the same as, rather than less than, the length of the tympanic bulla. The postorbital breadth is greater than in _fallenda_ and the anterior edges of the tympanic bullae are flush with the squamosals rather than projecting below the floor of braincase. In relation to the skull as a whole the preorbital and interorbital parts are larger.
In comparison with _streatori_, skulls of males are of about the same size, _anguinae_ being only 9 per cent heavier. The length of the tooth-rows is ordinarily less than, rather than about equal to, the length of the tympanic bulla; sagittal crest wanting rather than present since in _anguinae_ the temporal muscles meet usually only at the posterior end of the braincase instead of all along the midline on its top; tympanic bullae narrower and more nearly flush with squamosal (less protruded from braincase). Relative to the basilar length, the zygomatic breadth is more, the tympanic bullae are narrower, and the braincase is deeper at the anterior end of the basioccipital. The female is 41 per cent heavier than _streatori_, there being no overlap in most cranial and dental measurements. M1, however, is approximately the same size in each subspecies. The tooth-rows and tympanic bulla are of almost equal length whereas in _streatori_ the length of the tooth-rows is less than that of the bulla.
Differences from _olympica_, in males, are: M1 shorter; all other measurements of teeth and parts of skull averaging larger; skull 20 per cent heavier; tooth-rows averaging shorter than tympanic bulla rather than about the same; relative to basilar length, braincase deeper at anterior end of basioccipital and tooth-rows shorter. The skull of the female is 64 per cent heavier, larger in every measurement taken without overlap; temporal ridges meeting, rather than separated, at lambdoidal crest; length of tooth-rows about equal to, rather than shorter than, tympanic bulla; in relation to basilar length, skull deeper, orbitonasal length more, mastoid and zygomatic breadths more, and tympanic bullae shorter.
_Remarks._--References in the literature to this insular race mostly were under the name _streatori_ until 1932 when in the course of the present study the name _anguinae_ was proposed. A few specimens have been taken by nearly every student of small mammals who has collected on Vancouver Island. Arthur Peake and Herbert Laing have probably collected more specimens than any other two zoölogists.
_M. c. anguinae_ is noteworthy for the slight secondary sexual variation in size; the disparity between the two sexes is less than in any other American subspecies of _erminea_. By linear measurement the body of the female is only 7 per cent shorter than in the male (178 versus 191 mm.). Linear measurements and weights of the skulls of the two sexes are further indicative of this approximation in size. By weight the skull of the female is only a fourth lighter than that of the male, or, stated in another way, the male's skull is only a third heavier (1.2 versus 0.9 grams).
No geographic variation has been detected between lots of specimens from different parts of Vancouver Island. The one specimen available from Salt Spring Island presents no obvious differences from selected individuals from Vancouver Island.
The winter pelage is more often brown than white. Of 17 specimens seen in winter pelage or in transition pelage, only 6 are white. These 6 are from Comox, Stamp River, Hilliers, Jeune Landing and Port Alice. Of the 34 specimens in brown pelage, 7 have the dark color of the upper parts meeting on the abdomen. Six of the 34 have brown color on the pectoral region. In two, this is a separate patch but in the other four the dark color is a continuation of the upper parts and extends in front of each foreleg over part of the pectoral region, but the two extensions, one from either side, do not meet on the underparts. The color of the lips was recorded in 22 individuals: one had both the upper and lower-lips white; 7 had the upper lips brown and the lower lips white; in 14 both the upper and lower-lips were brown.
_Specimens examined._--Total number, 40, listed by localities from north to south as follows. Unless otherwise indicated, specimens are in the National Museum of Canada.
=British Columbia.= Vancouver Island: Cape Scott, 4; Shushartie, 1; Quatsino, 1[74]; Jeune Landing, 1[74]; Port Alice, 5[15]; Marble Creek, Quatsino Sound, 1[22]; Port Hardy, 5; Sayward, 2; Bear Lake, 4; Bear River, 1; Comox, 4(3[85]); Stamp River, Alberni, 1[31]; Errington, 1[74]; French Creek, 1[74]; Hilliers, 1[74]; Craigs Crossing, 1[74]; Nanaimo, 2[22]; Cowichan Lake, 1[22]; Duncan, 2[85]; Salt Spring Island, 1[85].
=Mustela erminea fallenda= Hall
Ermine
Plates 5, 6, 7, 11, 12 and 13
_Mustela erminea fallenda_ Hall, Journ. Mamm., 26:79, February 27, 1945; Hall, Journ. Mamm., 26:181, July 19, 1945.
_Putorius streatori_ Merriam, N. Amer. Fauna, 11:13, June 30, 1896 (part-Sumas).
_Type._--Male, adult, skull and skin; no. 7096, Nat. Mus. Canada; Huntingdon, British Columbia; May 21, 1927; obtained by C. H. Young, original no. 317.
The brown summer skin is well made. The skull (plates 5-7) is complete. Right p2 has the crown broken away; otherwise the teeth all are present and entire.
_Range._--On mainland in immediate vicinity of coast from probably opposite Texada Island, British Columbia, south to Lake Whatcom, Washington, and east to Mount Baker Range on International boundary. See figures 25, 27 on pages 95, 149.
_Characters for ready recognition._--Differs from _M. e. haidarum_, in both sexes, in light-colored underparts less than half the width of dark-colored upper parts, proximal two-thirds of under surface of tail colored like upper parts instead of underparts, interorbital breadth less than distance between glenoid fossa and posterior margin of external auditory meatus; from _M. e. richardsonii_ in both sexes, by upper lips brown rather than white, in males hind foot less than 41 and basilar length less than 38.3, in females hind foot less than 29, basilar length less than 31.4 and breadth of rostrum more, instead of less, than 30 per cent of basilar length; from _M. e. invicta_, in both sexes, by upper lips brown (not white); in males by skull averaging shorter (basilar length 35.7 versus 37.0); in females by breadth of rostrum more, instead of less, than 30 per cent of basilar length; from _M. e. anguinae_, in both sexes, by anterior margin of tympanic bulla projecting from floor of braincase rather than flush with squamosal (the difference is slight in females), in males by sagittal crest present, in females by total length less than 238 and tooth-rows longer than, instead of about same length as, tympanic bulla; from _M. e. streatori_, in both sexes, by black tip of tail more than half of length of tail-vertebrae, in males hind foot more than 33.7, tympanic bulla longer than, instead of about same length as, upper tooth-rows; weight of skull more than 1-1/4 grams, in females weight of skull more than 0.7 grams, length of lateral side of P4, 4 mm. or more; from _M. e. olympica_, in males, length of hind foot more than 33, black tip of tail more than 36.5 mm., weight of skull more than 1.2 grams, basilar length more than 33.5, in females length of hind foot more than 25.5, weight of skull more than 0.66 grams, basilar length more than 28.4; from _M. e. gulosa_, in both sexes, by anterior margin of tympanic bulla projecting below floor of braincase rather than flush with squamosal (the difference is slight in females), in males hind foot more than 33.5, weight of skull more than 1-1/4 grams, basilar length more than 33.9, in females by total length more than 222, hind foot longer than 26, weight of skull more than 0.7 grams, basilar length more than 29.
_Description.--Size._--Male: Seven adult topotypes yield average and extreme measurements as follows: Total length, 278 (249-305); length of tail, 77 (69-81); length of hind foot, 36.5 (34-40). A male topotype of unknown age weighed 113 grams.
Female: Two adult topotypes, with actual measurements in parentheses, average as follows: Total length, 232 (228-236); length of tail, 60 (57-62); length of hind foot, 27 (27-27). An adult from Morovitz Guard Station, Wash., weighed 54 grams.
_Color._--Winter pelage rarely white, brown pelage indistinguishable from summer pelage except for slightly more smoky tinge in winter in specimens from some localities; otherwise as described in _Mustela erminea streatori_ except that least width of color of underparts averaging, in seven adult topotypes, 18 (0-37) per cent of greatest width of color of upper parts. Black tip of tail averaging, in same series, 45 (38-52) mm. which is 58 (53-65) per cent of length of tail-vertebrae.
In comparison with _richardsonii_ and _invicta_, _fallenda_ differs in darker color of upper parts and their extension at the expense of the light-colored underparts which are narrower by a half. In correlation with this restriction in area of the light-colored underparts, the upper lips are brown instead of white. In comparison with _anguinae_, _olympica_ and _streatori_, the longer black tip on the tail is the principal difference in color. From _gulosa_, _fallenda_ differs in slightly darker color of upper parts and in narrow underparts, the width of the same being only about a fifth instead of a third of the width of the dark-colored upper parts.
_Skull._--Male (based on 7 adults): See measurements and plates 5-7. As described in _Mustela erminea richardsonii_ except that: Weight, 1.5 (1.3-1.7) grams; basilar length, 35.7 (34.3-38.2).
Female (based on 6 ads.): See measurements and plates 11-13. As described in _Mustela erminea richardsonii_ except that: Weight, 0.85 (0.73-1.0) grams; basilar length, 30.6 (29.4-31.7); breadth of rostrum more than 30 per cent of basilar length.
In comparison with _richardsonii_, skulls of males differ as follows: averaging smaller in every measurement taken with no overlap in several dimensions; 40 per cent lighter; in relation to basilar length, rostrum (orbitonasal length) longer and skull slightly broader interorbitally. Females average smaller in every cranial and dental measurement taken with no overlap in basilar length, length of tooth-rows and length of tympanic bulla; 22 per cent lighter; breadth of rostrum more, rather than less, than 30 per cent of basilar length; in relation to basilar length, pre-and interorbital parts of skull larger, and mastoid breadth more.
Differences from males of _olympica_ are: size larger with no overlap in most measurements; 50 per cent heavier; tympanic bullae longer than upper tooth-rows rather than of about equal length; in relation to basilar length, rostrum shorter, braincase wider and deeper, zygomata more expanded. Females are larger with no overlap in most measurements; 35 per cent heavier; in relation to basilar length, pre-and interorbital regions narrower, braincase deeper and wider across mastoids.
Differences from _streatori_, in males, are: skull averaging larger in every cranial and dental measurement taken; 36 per cent heavier; tympanic bulla longer than, instead of about same length as, upper tooth-rows. In females the inner lobe of M1 is shorter anteroposteriorly; otherwise all measurements of _fallenda_ average larger and it is 33 per cent heavier; rostrum and interorbital region broader in relation to remainder of skull.
In comparison with _gulosa_, skulls of males differ as follows: averaging larger in every measurement taken with no overlap in several dimensions; 50 per cent heavier; tympanic bullae with anterior margins projecting slightly below squamosals rather than flush with same; length of bulla more than, rather than about same as, that of upper tooth-rows. Considering the great difference in size, the relative proportions are remarkably alike. In females, length of inner lobe of M1 about the same; otherwise averaging larger in every measurement taken; 44 per cent lighter; relative to basilar length, tooth-rows longer, skull wider across zygomata and mastoids, rostrum and interorbital regions slightly narrower, skull shallower in plane of last upper molars.
Comparisons with _haidarum_, _invicta_ and _anguinae_ are made in accounts of those subspecies.
_Remarks._--Until the name _fallenda_ was proposed in the course of the present study, most of the specimens of this race were assigned to _streatori_.
Intergradation with _streatori_ is complete as it is also with _invicta_ and _richardsonii_, in other words with each of the subspecies whose ranges meet that of _fallenda_. In color and in size the difference is least between _streatori_ and _fallenda_. As between _fallenda_ and _invicta_ the size is not greatly different and the intergradation in color is gradual. Between _fallenda_ and _richardsonii_ intergradation is somewhat different and to fully appreciate its nature we should remember that the color of _fallenda_ resembles that of the saturate coastal races, _streatori_, _anguinae_ and _olympica_ although the black tip of the tail is longer. In this latter feature and in several cranial details, as well as in greater degree of secondary sexual variation in size, _fallenda_ resembles _richardsonii_. Because the two differ more than do most subspecies of ermine whose ranges meet, some of the intergrades at first inspection appear to be widely different from either parent stock. For example, specimens from Alta Lake, British Columbia, may give this impression because the combination of large size and dark color suggests a kind of ermine different from either _fallenda_ or _richardsonii_. In no instance, however, has there been found in these intergrades any character other than those occurring in one or the other of the two parent races.
Along the coast in the north part of the geographic range assigned to _fallenda_, some specimens nearly typical of _richardsonii_ have been taken so near to the place where fairly typical _fallenda_ was obtained that I have doubted whether there is intergradation in the usual fashion in this area; more specimens will have to be obtained from this coastal area to resolve the doubt one way or the other.