Chapter XIX: Introduction (18)

Female (based on no. 26153): See measurements and plates 37-39. As
described in _Mustela frenata frenata_ except that: Weight, 3.6
grams; basilar length, 44.5; zygomatic breadth less than distance
between condylar foramen and M1, or than between anterior palatine
foramen and anterior margin of tympanic bulla; tympanic bulla as
far posterior to foramen ovale as width of 4 or 5 upper incisors;
height of tympanic bulla not more than distance from its anterior
margin to foramen ovale; length of tympanic bulla more than length
of lower molar and premolar tooth-row or than length of rostrum.

The skull of the female is 43 per cent lighter than that of the
male.

Comparison of the skull with those of _M. f. perotae_, _goldmani_ and _neomexicana_ has been made in the accounts of those subspecies. As compared with that of _frenata_ the main difference is the less inflated tympanic bulla, the height of which is approximately equal to, rather than decidedly more than, distance from its anterior margin to foramen ovale.

_Remarks._--The first specimen known to have been preserved is the alcoholic in the British Museum of Natural History, taken in September, 1891, on the Río Santiago in Jalisco, by D. A. C. Buller. The other known specimens of this white-faced weasel are divided between the American Museum and the United States National Museum. The two referred specimens from Jalisco were the last of several helpful ones collected in México and Central America by J. H. Batty, and these two were taken less than three months before Batty's tragic death in Chiapas (see Allen, J. A., 1906:191). The five specimens from Michoacán were taken by Nelson or Nelson and Goldman together. Merriam had only three of these when he named the subspecies and remarked (1896:29) that "This form is the poorest subspecies described in the present paper." Although the form is not strongly marked, the two additional specimens from Michoacán and better comparative material than Merriam had confirm several of the differential characters ascribed to it by him and indicate the existence of still other characters.

_M. f. leucoparia_ occurs in the Sonoran and Transition life-zones. No. 27258 from Los Masos, and no. 26153 from Artenkiki (see specimens examined for other spellings) approach true _frenata_ in coloration. Each of these specimens has a few white hairs between the ears and the white patch between the eyes is confluent on one side only with the lateral white bands on the side of the head. No. 27258 from Los Masos has a dark spot at each angle of the mouth. The 7 other specimens are relatively uniform in coloration. Each has the white spot between the eyes confluent on both sides with the extensive white areas on each side of the face. None has a dark spot at either angle of the mouth. Of these 7 specimens, the type specimen and three others have white hairs forming a median line between the ears and a fifth specimen has a white spot behind each ear.

_M. f. leucoparia_ is most like _M. f. frenata_. Unlike _frenata_, _leucoparia_ has tympanic bullae that are less inflated, narrower and less projected, at their anterior margins, from the cranium. In these characters _leucoparia_ is intermediate between _M. f. frenata_ and _M. f. goldmani_. The latter subspecies has the least inflated, narrowest and least projecting tympanic bullae of the three. The black color of the head extends, on the average, farther posteriorly than in _M. f. frenata_ but not so far as in _M. f. goldmani_. The general color, too, is intermediate between that of _M. f. frenata_ and that of the much darker _M. f. goldmani_. The white facial markings are more extensive than in either _M. f. frenata_ or _M. f. goldmani_. This applies to both the white area between the eyes and the one on each side of the head between the ear and eye. _M. f. neomexicana_, whose range possibly meets that of _M. f. leucoparia_, also has more extensive white facial markings than _M. f. frenata_ but less extensive markings than _M. f. leucoparia_.

On the basis of skulls alone, specimens of _frenata_ from Tlalpam and those of _leucoparia_ from Los Reyes can hardly be distinguished. This fact, and the circumstance that the specimens from the northern part of the range of _leucoparia_ closely resemble _frenata_ in color, constitute sufficient evidence for regarding the two as only subspecifically distinct. The female, no. 26153 from Artenkiki, as mentioned above, approaches true _frenata_ in coloration. On this account it is not to be regarded as typical and it was because no other skulls of adult females were available that this one was used for comparison with females of allied races.

_M. f. leucoparia_ is, then, a subspecies of the large, temperate-zone group and is unique in possessing the maximum extent of white facial markings.

None of the seven skulls shows signs of having had the frontal sinuses infested with parasites.

_Specimens examined._--Total number, 8, all from México.
Localities are listed by states from north to south. Specimens
from Michoacán are in the United States National Museum; one from
Río Santiago is in the British Museum of Natural History; all
others are in the American Museum of Natural History.

=Nayarit.= Tepic, 1.

=Jalisco.= Río Santiago, 1; Los Masos, 1; "Artenkiki" (J. A.
Allen, 1906, p. 238, writes "Artenkikil" and, on p. 259,
"Artenkiki."), 1.

=Michoacán.= Zamora, 1; Los Reyes, 1; Pátzcuaro, 3.

=Mustela frenata perotae= Hall

Long-tailed Weasel

Plates 36, 37 and 38

_Mustela frenata perotae_ Hall, Carnegie Instit. Washington Publ.
473:100, November 20, 1936.

_Putorius frenatus_, Merriam, N. Amer. Fauna, 11: pl. 3, fig. 2,
June 30, 1896.

_Type._--Female, adult, skull and skin; no. 54278, U. S. Nat.
Mus., Biol. Surv. Coll.; 12,500 feet, Cofre de Perote, Veracruz,
México; May 26, 1893; obtained by E. W. Nelson; original no. 4864.

The skull (plates, 37-39) lacks the right zygomatic arch. Left p2
is missing. The skin is fairly well made and in good condition
except that the extreme tip of the tail has been broken off and
there are two holes in the right hind leg. The underparts show the
beginning of a spring molt.

_Range._--From 7500 (?) feet (Perote) to 13,500 feet
(Popocatépetl), Upper Sonoran, Transition and Boreal life-zones of
mountains along Puebla-México boundary, eastward to western
central Veracruz and south into Oaxaca. See figure 29 on page 221.

_Characters for ready recognition._--Differs from _M. f. frenata_,
its nearest relative, in extension from head of blackish onto
anterior fourth of neck; restriction of color of underparts (least
width of same less than 37 per cent of greatest width of color of
upper parts), height of tympanic bulla less than distance from its
anterior margin to foramen ovale; from _M. f. macrophonius_ and
_M. f. goldmani_ in presence of, rather than absence of, color of
underparts on hind feet; upper parts (black) Brussels Brown rather
than Argus Brown or darker; from _M. f. tropicalis_ in larger size
(adult female with total length more than 400, basilar length more
than 40, weight of skull more than 3 grams); postorbital breadth
less than combined length of upper premolars; m1 more than 5.4
long; from _M. f. leucoparia_ in white facial markings so
restricted that spot between eyes is not confluent with white
stripe in front of ear, or, if so, narrowly (less than 4 wide)
confluent; color of upper parts extending onto antipalmar face of
forefoot, least width of color of underparts not more than 40 per
cent of greatest width of color of upper parts; height of tympanic
bulla not more than three-fifths distance from its anterior margin
to foramen ovale.

_Description._--_Size._--Male: A nontypical specimen from Cerro
San Felipe, Oaxaca, measures: Total length, 500; length of tail,
205; length of hind foot, 52.

Female: The type specimen, measures: Total length, 418; length of
tail, 160; length of hind foot, 45.

In this male the tail is 70, and in the female, 62 per cent as
long as the head and body. In each the hind foot is longer than
the basal length.

The differences in external measurements between these two
specimens, representing the two sexes, are: Total length, 82;
length of tail, 45; length of hind foot, 7.

_Externals._--As described in _Mustela frenata frenata_.

_Color_ (based on type specimen).--Color and color pattern as
described in _Mustela frenata frenata_ except that: blackish of
sides and top of head extends one-fourth of way back to shoulders
from ears; throat and breast as well as chin white; remainder of
underparts near (16´ _c_) Ochraceous-Buff; least width of color of
underparts equals 36 per cent of greatest width of color of upper
parts; black tip of tail equal to 28 per cent of length of
tail-vertebrae.

_Skull and teeth._--Male (based on a referred specimen from Cerro
San Felipe which certainly is nontypical): See measurements. As
described in _Mustela frenata frenata_ except that: Weight, 4.9
grams; basilar length, 49.2; postorbital breadth more than
distance between posterior borders of P4 and P2; tympanic bulla as
far posterior to foramen ovale as width of 5 upper incisors;
height of tympanic bulla less than distance from its anterior
margin to foramen ovale; zygomatic breadth less than distance
between condylar foramen and M1 or than between anterior palatine
foramen and anterior margin of tympanic bulla.

Female (based on type specimen, an adult): See measurements and
plates 37-39. As described in _Mustela frenata frenata_ except
that: Weight 3.4 grams; basilar length, 43.5; zygomatic breadth
less than distance between condylar foramen and M1 or than between
anterior palatine foramen and anterior margin of tympanic bulla;
postorbital breadth less than width of basioccipital measured from
medial margin of one foramen lacerum posterior to its opposite;
tympanic bulla as far posterior to foramen ovale as width of 5 or
6 upper incisors; height of tympanic bulla one-half to
three-fifths 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 is 33 per cent lighter than that of the
nontypical (and smaller than average) male from Cerro San Felipe.

Comparison of the skull with that of _M. f. tropicalis_ is made in the account of that subspecies. Compared with the skull of _M. f._ _macrophonius_, that of the female of _perotae_ is more flattened, has the longitudinal dorsal outline distinctly concave rather than flat just behind the postorbital processes, and much wider tympanic bullae. Accordingly, the basioccipital is slightly narrower in _perotae_. The more marked postorbital constriction of the type specimen of _perotae_ possibly is due to its relatively greater age. As compared with the skull of _M. f. leucoparia_, that of the female of _perotae_ has less inflated tympanic bullae, the height of each being half as great as distance from its anterior margin to foramen ovale, whereas, in _leucoparia_ (as represented by no. 26153) the two distances are equal. As compared with that of _M. f. frenata_, the skull of the female of _perotae_ differs mainly in the lesser inflation of the tympanic bullae and their relative position. The height of each bulla is in _perotae_ only half as much as, but in _frenata_ more than, the distance from its anterior margin to foramen ovale. The anterior margin of the bulla is much less projected from the floor of the braincase in _perotae_. The squamosal anterior to each bulla is convex ventrally in _perotae_ but flat or concave ventrally in _frenata_.

_Remarks._--The type specimen and a juvenal female from the town of Perote were taken in the spring of 1893 by E. W. Nelson. Of these two, the type specimen was mentioned and figured by Merriam (1898:30, fig. 16 [= fig. 15], pl. 3, fig. 2) as _Putorius frenatus_. The referred nontypical specimen from Cerro San Felipe, Oaxaca, was referred by Merriam (op. cit.:29) to _Putorius frenatus goldmani_ with the comment that it was intermediate ". . . both in coloration and cranial characters, between typical _frenatus_ and _goldmani_;. . . ." No other published references to this subspecies, or specimens of it, have been seen. In 1941 and 1942, W. B. Davis and associates took four specimens along the boundary between the states of Puebla and México.

Although the specimen from Cerro San Felipe, Oaxaca, is referred to _Mustela frenata perotae_, to the description of which it answers best, that specimen, on account of its structural characters and geographic position relative to adjacent races, is in reality an intergrade between several of the adjacent races. Some of its intermediate characters are pointed out in the discussion of _M. f. goldmani_. In the specimens from 45 and 55 kilometers ESE of México (city) the black color of the top of the head does not extend so far behind the ears as in the holotype of _M. f. perotae_ and in this feature the two specimens show intergradation between the two subspecies, _perotae_ and _frenata_.

The type specimen taken on May 26, is acquiring new hair on the belly and lower sides which appears to be the result of a normal molt.

As would be expected from its geographic position, _M. f. perotae_ resembles _M. f. frenata_ of northern México and the high mountain forms of southern México more than it does the lowland tropical forms. This is true as regards size of entire animal, proportions of its parts, and size, general angularity and major proportions of its skull. The marked postorbital constriction, convex supralacrymal face of rostrum, width of tympanic bullae and angularity of the braincase place it nearest _M. f. frenata_ as does also the color and color pattern. The ventrally convex squamosal anterior to each tympanic bulla and the slight degree of projection from the cranium of the anterior margin of each tympanic bulla are intermediate in degree between the condition in _M. f. macrophonius_ and that in _M. f. frenata_. Thus _M. f. perotae_ combines several characters of _M. f. frenata_ on the one hand with some of _M. f. macrophonius_ on the other and in some features, for instance in the size, shape and degree of inflation of the tympanic bullae, presents intermediate stages of development.

On the eastern plain below the high mountain, Cofre de Perote, there ranges the similarly colored, smaller, tropical weasel, _Mustela frenata tropicalis_. Between _M. f. perotae_ and _M. f. tropicalis_ there is marked differentiation in the skulls with much less differentiation in coloration. The differences in typical skulls of the two subspecies are so pronounced that one would, at first glance, hardly believe it possible for direct intergradation to occur between them on the sides of this mountain. Merriam (1896:30) thought that it did not. The two skulls figured by him (_op. cit._:31) are a topotype of _M. f. tropicalis_ from Jico and the one which now is the type specimen of _M. f. perotae_. They show the great difference in size and proportions and are females of comparable ages, not of different ages as I suspected before examining the skulls. However, despite this marked difference in the skulls, there is some, although not conclusive, evidence of intergradation furnished by a young female from Xuchil, Veracruz. This specimen is described in connection with _M. f. tropicalis_ (see p. 366).

None of the seven skulls shows marked deformity of the interorbital region, but two of the three adults appear to have had these parts infested with nematodes.

_Specimens examined._--Total number, 7, all from México, listed by
localities from north to south. Specimens from Veracruz and Oaxaca
in the United States National Museum; remainder in Texas
Cooperative Research Collection.

=México=: Monte Río Frío, 45 Km. ESE México City, 1; 55 Km. ESE
México City, 1; N slope Mt. Popocatépetl, 13,555 ft., 1.

=Puebla.= Río Otlati, 8700 ft., 1.

=Veracruz.= Cofre de Perote, 12,500 ft., 1; Perote, 1.

=Oaxaca.= Cerro San Felipe, 10,000 ft., 1.

=Mustela frenata goldmani= (Merriam)

Long-tailed Weasel

Plates 1, 24, 25, 26 and 30

_Putorius frenatus goldmani_ Merriam, N. Amer. Fauna, 11:28, June
30, 1896; Elliot, Proc. Biol. Soc. Washington, 18:236, December
9, 1905.

_Mustela frenata goldmani_, Miller, U. S. Nat. Mus. Bull., 79:100,
December 31, 1912; Hall, Carnegie Instit. Washington Publ.
473:109, November 20, 1936.

_Type._--Male, adult, skull and skin; no. 77519, U. S. Nat. Mus.,
Biol. Surv. Coll.; Pinabete, Chiapas, México; February 10, 1896;
obtained by E. A. Goldman (on attached label collectors recorded
as Nelson and Goldman); original no. 9279.

The skull (plates 24 and 30) has the rostrum badly injured. All
the right, and part of the left nasal, the upper part of the right
maxilla, the postorbital process and intervening area of frontals
are missing. Each zygomatic arch is broken but the parts are
present and attached to the skull. The frontal and interorbital
regions are greatly malformed owing to parasites that infested the
sinuses. Right I2 and I3, right and left i3, and the medial parts
of the paraconid and protoconid of right m1 are missing. The light
facial markings are less extensive than in any of the referred
specimens. These markings consist of a separate spot between the
eyes and a white line, confluent with the color of the underparts,
on each side of the head, that extends from the base of the ear to
above the eye. The dark color of the underparts is represented at
the angles of the mouth by a spot on the left side and a similar
dark area, confluent with the dark color of the face, on the right
side. The large size, characters of the skull, and scrotal pouch
on the skin prove the specimen to be a male as stated on the
label.

_Range._--Two thousand five hundred feet (El Cipres, Guatemala) to
9500 feet (near Tecpám, Guatemala), Upper Tropical Life-zone of
mountains and western coasts of southern México, Guatemala and
Salvador. See figure 29 on page 221.

_Characters for ready recognition_ (characters based on
males).--Differs from _M. f. nicaraguae_ and _M. f. perda_ by
larger size (total length of adult males more than 489), least
width of color of underparts not less than 26 per cent of greatest
width of color of upper parts, weight of skull of adult male more
than 5 grams; from _M. f. macrophonius_ by smaller size (total
length of adult males less than 540), skull of male with basilar
length less than 52.5 and weight less than 6 grams; from _M. f.
perotae_ (typical specimens of same sex not available) by darker
color of upper parts which are Argus Brown or darker rather than
Brussels Brown; nonextension of color of underparts onto hind
feet; from _M. f. leucoparia_ in least width of color of
underparts not more than 37 per cent of greatest width of color of
upper parts; color of underparts not extended onto hind feet;
black tip of tail two-fifths rather than one-fourth as long as
tail-vertebrae; height of tympanic bulla less than four-fifths
distance from its anterior margin to foramen ovale.

_Description._--_Size._--Male: Four adults yield average and
extreme measurements as follows: Total length, 508 (500-512);
length of tail, 196 (185-207); length of hind foot, 55.5 (54-58).
Tail averages 63 (59-67) per cent as long as head and body. Length
of hind foot more than basal length.

Female: Typical specimen unknown.

_Externals._--Longest facial vibrissae black and reaching beyond
ear; carpal vibrissae wholly or in part of same color as upper
parts and reaching as far as hypothenar pad; hairiness of
foot-soles distinctly less than that shown in figure 20 on page
60.

_Color._--Spot between eyes, band, confluent with color of
underparts, on each side of head extending anterodorsally anterior
to each ear and posterior third of each upper lip, white;
remainder of sides and top of head and neck posteriorly to or
slightly behind shoulders, black; dark spots at angles of mouth
usually absent; tip of tail black; remainder of upper parts Argus
Brown or near (_n_) Argus Brown; chin, throat and breast white;
remainder of underparts near (16' _c_) Ochraceous-Buff; color of
underparts extending distally on posterior sides of forelegs onto
medial toes and on hind legs to points between knees and heels.
Least width of color of underparts, in five adult males, averaging
28 (extremes 26-33) per cent of greatest width of color of upper
parts; black tip of tail, in four adult males, averaging 40 per
cent of length of tail-vertebrae.

_Skull and teeth._--Male (based on five adults): See measurements
and plates 24-26, 30; weight, 5.4 (5.3-5.5) grams; basilar length,
49.9 (49.6-51.3); zygomatic breadth (except in no. 12523 from
Salvador) more than or equal to distance between condylar foramen
and M1 or 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 median
margin of one foramen lacerum posterior to its opposite;
interorbital breadth 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 length of P4; anterior margin of tympanic bulla as far
posterior to foramen ovale as width of five 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 shorter than or equal to length
of rostrum; anterior margin of masseteric fossa immediately behind
m2.

Female: Typical skull unknown.

Comparison of male skull with that of _M. f. perda_ made in discussion of that form. Comparison with that of _M. f. nicaraguae_ shows similar differences, some of which are more pronounced. For example, squamosals anterior to tympanic bullae more convex ventrally and these bullae project less from braincase than in _M. f. perda_; thus the difference in these features is greater between _goldmani_ and _nicaraguae_ than between _goldmani_ and _perda_.

As compared with the skull of the male of _M. f. macrophonius_, each one of the skulls of the adult males of _M. f. goldmani_ is smaller in every measurement taken, with two exceptions. The width of the tympanic bullae was more in three specimens of _M. f. goldmani_ as was also the depth of the same in three specimens. Relative to the basilar length all but two of these measurements average less in _goldmani_; the exceptions are the zygomatic breadth and depth of the skull at the anterior margin of the tympanic bullae which average more. Relative to the basilar length, the orbitonasal length and depth of the skull at the posterior margin of M1 are less in each skull of _goldmani_. Thus, excepting the width and height of the tympanic bullae and the relative zygomatic breadth and relative depth of the braincase posteriorly, the skull of _goldmani_ is shorter and relatively as well as actually narrower and lighter throughout.

As compared with the skull of the male of _M. f. leucoparia_, that of _M. f. goldmani_ averages a trifle shorter and no skull of _goldmani_ equals that of _leucoparia_ in actual or relative zygomatic and mastoid breadths or length or height of tympanic bullae. In depth, the skull of _goldmani_ averages actually and relatively greater. Its teeth are smaller. The squamosal anterior to each tympanic bulla is convex ventrally whereas it is concave ventrally in _leucoparia_ as in _frenata_.

_Remarks._--When Merriam (1896:28) named this subspecies, he had only one specimen but he called attention to the more important diagnostic characters, which additional specimens show pertain to the race as a whole.

_M. f. goldmani_ in typical form occurs in high mountains of the Upper Tropical Life-zone and is most closely related to _M. f. frenata_ and _M. f. macrophonius_. The altitude at which the two specimens were taken, twenty miles southeast of Teopisca in Chiapas, is not known. Merriam (1896:28) states that the type specimen was obtained at "about 8200 feet." The specimen taken by Stirton in Salvador comes from 8000 feet and the one obtained by Barber in Guatemala from 9500 feet. The specimen from Dueñas, the skin alone of a young animal, is not instructive.

As regards size, _goldmani_ is larger than the immediately adjacent subspecies from the Lower Tropical Life-zone but is smaller than _M. f. leucoparia_ or _macrophonius_. As compared with _M. f. frenata_, _goldmani_ is longer, has an actually as well as relatively shorter tail, and a much longer hind foot.

The most outstanding difference in externals from _frenata_ is the naked foot soles.

Molting probably takes place twice each year although actual proof of this is lacking. In number 133254 from twenty miles southeast of Teopisca, taken on May 12, the molt is well advanced. Another specimen from the same place still retains the winter coat.

In color, _goldmani_ is much darker than _frenata_, has less extensive white facial markings, longer black tip on tail, more restricted color of underparts, and lacks the extension of color of the underparts onto the hind feet.

Of the adult males from the high mountains, the type specimen from Chiapas is lightest, and the one from Salvador is darkest. This progressively darker color to the southward probably is geographic variation.

In total length and relative and actual length of tail, the specimen from Salvador is the smallest of the five adult males from the higher mountains. In addition to its darker color and smaller size, no. 12523 from Salvador shows certain distinctive cranial characters. The zygomatic breadth is less than, rather than more than, or equal to, the distance between the condylar foramen and M1 or than that between the anterior palatine foramen and the anterior margin of the tympanic bulla. This difference appears to be correlated with geographic position, since no. 15953 from Guatemala has the three distances about equal and therefore is intermediate in this respect between the specimen from Salvador and those from Chiapas, in which the zygomatic breadth is greater than the other two measurements. Also in the greater depth of the skull and smaller size of the teeth, this specimen from Salvador approaches the subspecies of the Lower Tropical Life-zone. It has, however, the longest, highest and widest tympanic bullae of any of the five specimens. The amount of ventral convexity of the squamosal in front of each tympanic bulla appears not to be greater than in the other specimens.

As indicative of intergradation with _perotae_, _leucoparia_ and possibly _frenata_, there is the specimen from Cerro San Felipe, Oaxaca. The degree of restriction of the color of the underparts is intermediate between that of _goldmani_ and _leucoparia_. The same is true as regards the amount of projection from the braincase of the anterior margins of the tympanic bullae. The squamosal immediately anterior to each tympanic bulla is flat instead of ventrally convex as in _goldmani_ or ventrally concave as in _leucoparia_ and _frenata_. In accordance with the custom adopted in this paper of referring every specimen to some one subspecies, this specimen from Cerro San Felipe is referred to _Mustela frenata perotae_, to the description of which it most nearly answers.

Possibly _goldmani_, as here constituted, is a composite form. The specimens from the high mountains closely resemble one another. However, a specimen, no. 68541 from "Finca El Cipres," Guatemala, which place Mr. G. Goodwin tells me is at an elevation of 2500 feet, approximately 5 miles north of Retalhuleu, has a basilar length of 47.3 and is correspondingly small in other parts. This suggests the existence of a small, lowland race on the western side of the central divide corresponding to _perda_ and _tropicalis_ on the eastern side. From only a few miles away, at San Sebastian, there is available, the adult skull of a still smaller animal. This skull only, no. 41026, in the Berlin Zoological Museum, has a basilar length of 46.1, zygomatic breadth of 27.4, and other cranial measurements notably smaller than those of specimens from the high mountains. A skin-only, no. 12038, collection of Donald R. Dickey, from La Cebia, altitude 2150 feet, near the city of San Salvador, seemingly represents an animal smaller than typical _goldmani_. This specimen from La Cebia has the light color of the underparts extended distally on the hind legs to the tips of the toes as in _M. f. tropicalis_. However, the upper parts are darker and resemble those of _M. f. goldmani_. A fourth specimen from only 3500 feet elevation, on the south side of Volcano Tajumulco, Guatemala, no. 41768, Field Museum of Natural History, a subadult male, measures only 490 in total length and has the least color of the underparts so restricted as to amount to only 22 per cent of the greatest width of the color of the upper parts. Both these features are suggestive of the lowland races.

These four specimens indicate that the lowland population on the western side of the divide is smaller than the mountain population. The juvenile from Carolina and a young male from Finca Cipres, however, both closely resemble individuals of _goldmani_ from the higher mountains. All these animals here are referred to _goldmani_. More specimens may reveal an amount and a pattern of geographic variation in weasels of this region that will require application of another subspecific name.

The female, no. 68540, from Puebla agrees remarkably well with the skull of the female, no. 132528, of _macrophonius_. Differences displayed by the specimen from Puebla are its slightly narrower braincase and longer space between the foramen ovale and anterior end of the tympanic bulla. Considering the far eastern location of Puebla (just north of Río Motagua, at 89° W, according to a sketch map provided by Mr. G. G. Goodwin), this specimen might be expected to show some approach to the small lowland races. Actually, however, it displays the characters of _goldmani_ better than does the subadult female from Volcano San Lucas, which is nearer the metropolis of _goldmani_, and I assume at a higher elevation than Puebla.

Concerning this weasel Merriam (1896:29) says: "Mr. E. W. Nelson writes me that this fine weasel is found sparingly in the forest about Pinabete, Chiapas, at an altitude of 7000 to 8000 feet (2100 to 2500 meters). The type specimen was shot in the afternoon while hunting on a heavily wooded hill slope. It was heard making long, slow leaps over the dry, crisp leaves. Coming to a log, it stood up and rested its fore feet on the log, in which position it was shot by Mr. Goldman."

The specimen taken by R. A. Stirton in Salvador comes from an elevation of 8000 feet in the rain forest of the Upper Tropical Life-zone. Mr. Stirton tells me that one morning on visiting his traps set for small rodents, he found in one the partly eaten remains of a _Heteromys_. Leaving these remains as found he placed a steel trap beside them and on the following morning found the male weasel in the trap.

At least three of the ten specimens had the frontal sinuses infested with parasites.

_Specimens examined._--Total number, 15, listed by localities from
north to south, and unless otherwise indicated in the American
Museum of Natural History.

=México=: _Chiapas_: 20 mi. SE Teopisca, 2[91]; Pinabete, 1[91].

=Guatemala=: Puebla, 1; Finca Porvenir, 3500 ft., S slope Volcan
Tajumulco, 1[60]; Sierra [=? Cerro] Santa Elena, 9500 ft. (near
Tecpám), 1[60]; Carolina, 1; Volcano San Lucas, 1; "Finca El
Cipres," 1; "Finca Cipres," 2500 ft., 1; Finca San Isidro, San
Sebastión, Dept. Retalhuleu, 1[4]; Dueñas, 1[7]; no locality more
definite than Guatemala, 1[7].

=El Salvador=: Los Esesmiles, 8000 ft., Chalatenango, 1[59]; La
Cebia, 2150 ft., near San Salvador, 1[59].

=Mustela frenata macrophonius= (Elliot)

Long-tailed Weasel

Plates 24, 25, 26, 30, 37, 38 and 39

_Putorius macrophonius_ Elliot, Proc. Biol. Soc. Washington,
18:235, December 9, 1905.

_Mustela macrophonius_, Miller, U. S. Nat. Mus. Bull., 79:100,
December 31, 1912.

_Mustela frenata macrophonius_, Hall, Carnegie Instit. Washington
Publ. 473:109, November 20, 1936.

_Type._--Male, adult, skull and skin; no. 14063, Field Mus. Nat.
Hist.; Achotal, Veracruz, México; January 15, 1904; obtained by
Edmund Heller and Charles M. Barber; original no. 3424.

The skull (plates 24-26, 30) is complete and unbroken. Excepting
right P2, which has been aborted or broken away, all the teeth are
present. The skin is well made and in good condition. As shown by
the scrotal pouch, the specimen is a male.

_Range._--Tropical Life-zone, probably into Boreal life-zones, of
mountains along eastern border of southern Veracruz. See figure 29
on page 221.

_Characters for ready recognition._--Differs from _M. frenata
frenata_ and _M. f. perotae_ and _M. f. leucoparia_ in lacking
color of underparts on hind feet and in larger skull (skulls of
adult males with basilar length more than 52.5); from _M. f.
goldmani_ by larger size of skull (see above) and entire animal
and wider tympanic bullae; from _M. f. tropicalis_ and _M. f.
perda_ by larger size (total length of adult males more than 510),
postorbital breadth amounting to less than combined length of
upper premolars.

_Description._--_Size._--Male: External measurements of the type
specimen, an adult, are: Total length, 598; length of tail, 246;
length of hind foot, 59. Tail 70 per cent as long as body; length
of hind foot more than basal length.

Female: The skin, without field collector's measurements, of an
adult female from Pérez, Veracruz, shows this sex to be
correspondingly large. Because the skin is understuffed and
because the hind feet are skinned out, reliable measurements can
not be obtained from the dried skin.

_Externals._--As described in _Mustela frenata goldmani_ except
that all carpal vibrissae are of same color as upper parts and
that hairiness of foot-soles is halfway between that shown in
figures 20 and 21.

_Color._--As in darkest individuals of _M. f. goldmani_, thus,
color of upper parts on posterior part of back near (_n_) Argus
Brown. Color of underparts near (12) Mikado Orange in a juvenile,
extending distally on posterior sides of forelegs onto inner toes
and on hind legs to points between knees and heels. Least width of
color of underparts 28 per cent of greatest width of color of
upper parts. Black tip of tail 34 per cent of length of
tail-vertebrae.

_Skull and teeth._--Male (based on type specimen): See
measurements and plates 24-26, 30. As described in _Mustela
frenata frenata_ except that: Weight, 6.9 grams; basilar length,
54.1; zygomatic breadth less than distance between condylar
foramen and M1 or that between anterior palatine foramen and
anterior margin of tympanic bulla; interorbital breadth less than
distance between foramen opticum and anterior margin of tympanic
bulla; anterior margin of tympanic bulla as far posterior to
foramen ovale as width of 4 to 6 upper incisors; height of
tympanic bulla less than distance from its anterior margin to
foramen ovale; anterior margin of masseteric fossa below posterior
half of m2.

Female (based on no. 132528): See measurements and plates 37-39.
As described in _Mustela frenata frenata_ except that: Weight, 3.6
grams; basilar length, 43.5; zygomatic breadth less than distance
between condylar foramen and M1 and more or less than (in the
single specimen, equal to) that between anterior palatine foramen
and anterior margin of tympanic bulla; least width of palate more
or less than (about equal to) outside length of P4; tympanic bulla
as far posterior to foramen ovale as width of 4 or 5 upper
incisors; height of tympanic bulla less than distance from its
anterior margin to foramen ovale.

The skull of the female is 48 per cent lighter than that of the
male.

Comparison of the skull with that of _M. f. goldmani_ is made in the account of that subspecies. Similar differences probably exist between males of _perotae_ and _macrophonius_. As compared with skulls of males of _M. f. tropicalis_ and _perda_, the skull of the male of _macrophonius_ is larger in every measurement taken. The postorbital constriction is less, rather than more, than the combined length of the upper premolars. Relative to the basilar length, the following measurements are less than in any specimen of _tropicalis_ or _perda_: length of tooth-rows; orbitonasal length; depth of skull at posterior border of upper molars; and depth of skull at anterior margin of basioccipital.

_Remarks._--This large weasel appears to have escaped the notice of naturalists until the spring of 1903 when J. Friesser obtained an adult female and juvenal male at Pérez for the collection of the United States Bureau of Biological Survey. These specimens were tentatively referred to _Mustela tropicalis_. In the following January, Edmund Heller and Charles M. Barber obtained the adult male that was made the type specimen by Elliot who did not see, or if he did, did not mention, the specimens from Pérez. He did, however, refer a young female from Xuchil, Veracruz, to his _Putorius macrophonius_. This young female is here referred to _Mustela frenata tropicalis_.

The extent of the geographic range of this subspecies is not well known.

_Mustela frenata macrophonius_ and _M. f. texensis_ are the largest American weasels. The basilar length in the type specimen is greater by one-tenth of a millimeter than in the type specimen of _M. f. texensis_. The other cranial measurements taken are greater in _M. f. texensis_. The skull of the female from Pérez is one of the largest skulls examined of that sex. The juvenal male has teeth as large as those of the type specimen and the skull is the largest for its age of any seen. Although the skin of the female is understuffed and hence does not provide reliable measurements, it shows that the female is also large.

The white bands in front of the ears are confluent with the white patch between the eyes on one side only in one specimen. It is the juvenal male. These bands are not confluent with the color of the underparts on either side in the female and on one side only in the adult male. None of the specimens has a white patch between the ears. The dark spot at each angle of the mouth is present only in the juvenile where it occurs on each side. Of the three specimens, the juvenile is the darkest and the adult male the lightest. The white facial markings are most extensive in the juvenal male and the least extensive in the adult female.

_M. f. macrophonius_ most closely resembles _M. f. goldmani_ but in the relatively flattened braincase, deep constriction of the postorbital region and general angularity of the skull approaches _M. f. perotae_ and _M. f. frenata_.

Only one of the three skulls, that of the female, shows evidence of infestation of the frontal sinuses by parasites, and this did not result in malformation of the interorbital region.

_Specimens examined._--Total number, 3, all from México, listed by
localities from north to south.

=Veracruz.= Achotal, 1 (Field Mus. Nat. Hist.); Pérez, 2 (U. S.
Nat. Mus.).

=Mustela frenata tropicalis= (Merriam)

Long-tailed Weasel

Plates 25, 26, 27, 30, 37, 38 and 39

_Putorius tropicalis_ Merriam, N. Amer. Fauna, 11:30, pl. 3, figs.
5, 5a, 6, 6a, text fig. 16, June 30, 1896; Merriam, Proc. Biol.
Soc. Washington, 15:68, March 22, 1902.

_Putorius frenatus_, Merriam, N. Amer. Fauna, 11:27, June 30, 1896.

_Mustela tropicalis tropicalis_, Miller, U. S. Nat. Mus. Bull.,
79:100, December 31, 1912; Allen, Bull. Amer. Mus. Nat. Hist.,
35:99, April 28, 1916.

_Mustela frenata tropicalis_, Hall, Carnegie Instit. Washington
Publ. 473:109, November 20, 1936.

_Type._--Male, adult, skull and skin; no. 54994, U. S. Nat. Mus.,
Biol. Surv. Coll.; Jico, Veracruz, México; July 9, 1893; obtained
by E. W. Nelson; original no. 5195.

The skull (plates 25-27, 30) is complete. All the upper incisors,
except the second and third on the left side, are missing. The
right upper canine is broken. The skin is well made and in good
condition.

_Range._--Up to 5000 feet (as now known) in Tropical Life-zone of
Veracruz, México. See figure 29 on page 221.

_Characters for ready recognition._--Differs from _M. f. frenata_
and _M. f. perotae_ in least width of color of underparts not
exceeding 36 per cent of greatest width of color of upper parts
and in postorbital breadth exceeding length of upper molar and
premolar tooth-rows; from _M. f. macrophonius_ and _M. f. perda_
in least width of color of underparts averaging more than 29 per
cent of greatest width of color of upper parts; and from _M. f.
perda_ by longer tympanic bullae which in males are more than
14.9; and from _M. f. macrophonius_ by lesser basilar length (not
more than 48) and in postorbital breadth exceeding length of upper
molar and premolar tooth-row.

_Description._--_Size._--Male: The type specimen and no.
12764/11058, a subadult, from Jalapa, Veracruz, measure,
respectively, as follows: Total length, 444, 442; length of tail,
175, 160; length of hind foot, 50, 47. The tail is 65 and 57 per
cent as long as the head and body. The hind foot is more or less
than (approximately equal to) the basilar length.

Female: Merriam (1896:31) gives the measurements of a female
topotype (probably no. 54993, U. S. Nat. Mus., which has no
measurements written on the attached label) as: Total length, 333;
length of tail, 121; length of hind foot, 37. The length of the
tail amounts to 57 per cent of the length of the body. The length
of the hind foot of no. 54993, U. S. Nat. Mus. is the same as the
basal length.

The differences in external measurements between the male and the
female topotypes are: Total length, 111; length of tail, 54;
length of hind foot, 13.

_Externals._--As described in _Mustela frenata frenata_ except
that carpal vibrissae do not reach apical pad of fifth digit and
hairiness of foot soles is less.

_Color._--As described in _M. f. frenata_ except that: Blackish of
head extends half way or more from ears to shoulders; upper parts
near (14) Brussels Brown or slightly faded tone 2 of Maroon of
Oberthür and Dauthenay, pl. 341; underparts of juvenal pelage near
(_a_) Ochraceous-Buff. Least width of color of underparts
averaging (in three specimens from Jico and one from Jalapa) 34
(extremes 30-37) per cent of greatest width of color of
underparts. Black tip of tail, in two male topotypes, 57.5 (55 and
60) mm. long; thus longer than hind foot and in each individual
comprising 34 per cent of length of tail-vertebrae.

As compared with _M. f. frenata_: White facial markings slightly
less extensive; blackish (not black) of head extending onto neck;
upper parts slightly darker; ventral side of tail noticeably
darker; color of underparts more restricted, averaging
approximately one-third rather than nearly one-half width color of
upper parts; black tip of tail one-third rather than one-fourth
length of tail and much longer than hind foot. Similar differences
of lesser amount exist between _perotae_ and _tropicalis_. _M. f.
perda_, _macrophonius_ and _goldmani_ bear the opposite relation
to _tropicalis_. That is to say, in the latter: White facial
markings slightly more extensive; blackish of head less extended
over neck; upper parts markedly lighter; color of underparts less
restricted and black tip of tail shorter.

_Skull and teeth._--Male (based on type specimen and a subadult,
no. 11058, from Jalapa): See measurements and plates 25-27, 30. As
described in _Mustela frenata perda_ except that: Weight 4.7 (4.6
and 4.7) grams; basilar length 46.7 (45.5 and 47.8); zygomatic
breadth more or less than distance between condylar foramen and M1
or than between anterior palatine foramen and anterior margin of
tympanic bulla; least width of palate more than length of P4;
anterior margin of tympanic bulla as far posterior to foramen
ovale as width of 4 (including I3) upper incisors; anterior margin
of masseteric fossa below middle of m2 or posterior to that tooth.

Female (based on no. 54993 and no. 1060): See measurements and
plates 37-39. As described in _Mustela frenata perda_ except that:
Weight (of 54993) 2.2 grams; basilar length, 37.5 (36.0-39.0);
zygomatic breadth more or less than distance between anterior
palatine foramen and anterior margin of tympanic bulla; least
width of palate more than greatest length of P4; height of
tympanic bulla equal to one-third to three-fourths of distance
from its anterior margin to foramen ovale.

The skull of the adult female is 53 per cent lighter than that of
the type specimen, a male.

Comparison of the skulls of males and females with those of _M. f. perda_, the nearest relative, has been made in the discussion of that subspecies. Some of the features that readily distinguish skulls of _M. f. tropicalis_ from those of _M. f. frenata_, _perotae_ and _macrophonius_ are as follows: Weight less than 4.8 grams; basilar length less than 48; postorbital breadth more than length of upper M-Pm tooth-row. The skulls of male _frenata_, _perotae_ and _macrophonius_ are much larger, heavier, and are decidedly more angular with more constricted postorbital region the least width of which is less than the length of the upper premolars. In _frenata_ the anterior margins of the tympanic bullae are protruded much farther from the braincase. The skull of the female of _M. f. tropicalis_ is smaller, weighing less than 3 grams; basilar length less than 41; postorbital breadth more than length of upper molar and premolar tooth-row.

_Remarks._--This subspecies was originally described by Merriam as a full species. Later he described _Putorius tropicalis perdus_ as another subspecies. Allen (1916) placed _P. t. perdus_ in synonymy but named _Mustela tropicalis nicaraguae_ as new. In the present paper all three forms are recognized but are regarded as only subspecifically distinct from the other bridled weasels of México and Central America.

The limits of the geographic range of _tropicalis_ are fairly well known on the south and west but the only specimen available from the tropical coastal region north of Jico, is a young female from a point 50 miles south of Victoria. Thus, how far north along the coast it ranges toward Matamoros, where _M. f. frenata_ occurs, is not known. The three specimens from Jico, a young female from Jalapa and another adult collected by J. Potts and labeled as coming from México City, are assumed to be typical. The latter specimen certainly came from an elevation lower than that of México City because _M. f. frenata_ occurs there. Although the female from Jalapa, agrees well with specimens from Jico, a male, no. 12764/11058, from Jalapa, has a relatively broader skull, as in _perda_, although the tympanic bullae are short as in _tropicalis_. The resemblances to _perda_ in features of coloration are: slightly darker upper parts, and the termination just below the knees of the color of the underparts. There are three specimens labeled as from Orizaba that indicate intergradation with _perotae_ as does also the coloration of the juvenal female from 5 kilometers north of Jalapa. The specimens labeled as from Orizaba are old, poorly-prepared skins, only two of which have partial skulls. The size and coloration of the skins suggest _perotae_ as do also the partial skulls in some respects although the skulls show greater resemblance to those of _tropicalis_.

The topotype, female, no. 54993, was figured by Merriam (1896, fig. 16, p. 31) along with that of what now is the type specimen of _M. f. perotae_. Merriam called attention to the great difference in size between the skulls of the two sexes of _M. f. tropicalis_ and compared the condition to that found in _noveboracensis_. Although the skull of the female from Jico is fully adult, it probably is exceptionally small.

The young female from Xuchil is indistinguishable in coloration from the juvenal female of _M. f. perotae_ from Perote, but in size of skull and size of teeth is intermediate between the female of tropicalis from Jalapa and the females from Cofre de Perote.

There is then, indication of intergradation with _M. f. perotae_ as well as with _M. f. perda_. _M. f. tropicalis_ differs from _M. f. perotae_ and _M. f. frenata_ in about the same way that _M. f. perda_ differs from _M. f. goldmani_ and _M. f. macrophonius_. _M. f. tropicalis_ and _perda_ each is smaller and more intensely colored than _goldmani_ and _macrophonius_, and inhabits the lowland to the east of their highland relative.

At least five of the nine skulls have the frontal sinuses infested by parasites.

_Specimens examined._--Total number, 13, all from México, listed
by localities from north to south. Unless otherwise indicated
specimens are in the collection of the United States National
Museum.

=Tamaulipas.= 50 mi. S Victoria, 1[71]. Near? México City, 1.

=Veracruz.= Jico, 3; 5 km. N Jalapa, 1[90]; Jalapa, 2 (1[2],
1[75]); Xuchil, 1[60]; Orizaba, 4 (2[75], 1[4]).

=Mustela frenata perda= (Merriam)

Long-tailed Weasel

Plates 25, 26, 27, 30, 37, 38 and 39

_Putorius tropicalis perdus_ Merriam, Proc. Biol. Soc. Washington,
15:67, March 22, 1902.

_Putorius (Gale) brasiliensis frenatus_, Coues, Fur-bearing
animals, p. 142, 1877 (part).

_Mustela tropicalis perda_, Miller, U. S. Nat. Mus. Bull., 79:100,
December 31, 1912.

_Mustela tropicalis tropicalis_, Allen, Bull. Amer. Mus. Nat.
Hist., 35:99, April 28, 1916.

_Mustela frenata perda_, Hall, Carnegie Instit. Washington Publ.
473:109, November 20, 1936.

_Type._--Male, subadult, skull and skin; no. 100041, U. S. Nat.
Mus., Biol. Surv. Coll.; Teapa, Tabasco, México; March 31, 1900;
obtained by E. W. Nelson and E. A. Goldman; original no., 14074.

The skull (plates 25-27, 30) is unbroken and all the teeth are
present and entire. The skin is well made and in good condition.

_Range._--Fifty feet (Chichén Itzá) to 4000 feet (San Vicente) in
Lower Tropical Life-zone south from southern Veracruz through
southern México into Guatemala. See figure 29 on page 221.

_Characters for ready recognition._--Differs from _M. f.
nicaraguae_ in lesser extent of color of underparts (not more than
22 per cent of greatest extent of color of upper parts), black tip
of tail more than 38 per cent of length of tail, and broader skull
(in adult males, mastoid breadth more than 23.9 and zygomatic
breadth more than 27.4); from _M. f. tropicalis_ in more
restricted color of underparts (least width of color of underparts
less than 28 per cent of greatest width of color of upper parts)
and shorter tympanic bullae, which in males are less than 15; from
_M. f. goldmani_ by total length not exceeding 489, least width of
color of underparts not exceeding 24 per cent of greatest width of
color of upper parts, weight of adult skull less than 5 grams and
basilar length less than 48.5.

_Description._--_Size._--Male: The type specimen and another
subadult from San Vicente, Chiapas, measure, respectively, as
follows: Total length, 473 and 443; length of tail, 184 and 169;
length of hind foot, 51 and 51.5. The tail is 62 and 64 per cent
as long as the head and body. The length of the hind foot is
greater than the basal length.

Female: Estimates made from the dried skin of no. 218036 are:
Total length, 375; length of tail, 140; length of hind foot, 40.
The hind foot of no. 65422 from Catemaco also measures 40.

The average differences in external measurements of the two sexes
are: Total length, 83; length of tail, 37; length of hind foot,
11.

_Externals._--As described in _Mustela frenata goldmani_ except
that hairiness of foot soles is slightly less.

_Color._--As described in _Mustela frenata goldmani_ except that:
back near (_n_) Argus Brown or Carbon Brown, tone 3, of Oberthür
and Dauthenay, pl. 342; underparts Ochraceous-Buff. Least width of
color of underparts, in four specimens, averaging 20 (extremes
18-22) per cent of greatest width of color of upper parts; black
tip of tail, in two subadult males, averaging 48 (extremes 46-49)
per cent of length of tail-vertebrae.

_Skull and teeth._--Male (based on type specimen and subadult no.
132997 from San Vicente): See measurements and plates 25-27, 30;
weight 4.4 grams (same for each); basilar length 45.7 (45.3 and
46.1); 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
(approximately equal to) length of upper premolars and greater
than width of basioccipital measured from medial margin of one
foramen lacerum posterior to its opposite; interorbital breadth
less than distance between foramen opticum and anterior margin of
tympanic bulla; breadth of rostrum not greater 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 4-1/2 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 or shorter than rostrum;
anterior margin of masseteric fossa below middle of m2.

Female (based on two subadults, nos. 65422 and 218036): See
measurements and plates 36-39; weight, 2.4 (2.3-2.5) grams;
basilar length, 40.5 (40.4-40.6); 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 than length of upper premolars or than
width of basioccipital measured from medial margin of one foramen
lacerum posterior to its opposite; least width of palate more than
outside length of P4 and less than inside length of same; anterior
margin of tympanic bulla as far posterior to foramen ovale as
width of 5 or 6 upper incisors; height of tympanic bulla equal to
one-third to one-half 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 (about equal to)
length of rostrum.

The skull of the female averages 48 per cent lighter than that of
the male.