_Plectrophanes_, MEYER, “Taschenbuch, 1810.” Agassiz. (Type, _Emberiza
nivalis_.)
_Centrophanes_, KAUP, “Entw. Gesch. Europ. Thierwelt, 1829.” Agassiz.
(Type, _E. lapponica_.)
GEN. CHAR. Bill variable; conical; the lower mandible higher than the
upper; the sides of both mandibles (in the typical species) guarded by
a closely applied brush of stiffened bristly feathers directed
forwards, and in the upper jaw concealing the nostrils; the outlines
of the bill nearly straight, or slightly curved; the lower jaw
considerably broader at the base than the upper, and wider than the
gonys is long. Tarsi considerably longer than the middle toe; the
lateral toes nearly equal (the inner claw largest), and reaching to
the base of the middle claw. The hinder claw very long, moderately
curved and acute, considerably longer than its toe; the toe and claw
together reaching to the middle of the middle claw, or beyond its tip.
Wings very long and much pointed, reaching nearly to the end of the
tail; the first quill longest; the others rapidly graduated; the
tertiaries a little longer than the secondaries. Tail moderate, about
two thirds as long as the wings; nearly even, or slightly emarginated.
[Line drawing: _Plectrophanes nivalis._
19632]
The species of this genus are essentially boreal and cosmopolitan,
although America possesses four species not found, like her two
others, in the Old World. They are all ground-birds, collecting in
large flocks, in autumn and winter, on prairies and plains, some of
the species passing far to the southward. There is much variation in
the color, and in the details of structure of bill and feet. In _P.
nivalis_ alone is the fringe of bristly feathers along the side of the
bill very distinct. The gonys also is exceptionally short, being less
than half the length of the culmen.
[Illustration: _Plectrophanes nivalis._]
The females are less strongly marked than the males, lacking the
distinct patches of black (which, however, are nearly always faintly
indicated), and other characters, and are streaked like the
_Spizellinæ_.
Species and Varieties.
A. Prevailing color white.
1. P. nivalis. ♂. Back, scapulars, ends of tertials, alula,
terminal half of primaries and the middle tail-feathers, deep
black; otherwise pure white. ♀. The black replaced by grayish
with black spots; crown grayish spotted with black. Young
considerably tinged with ochraceous. _Hab._ Circumpolar
regions; south in winter into the United States.
B. Above brown, spotted with black. ♂. Crown black.
_a._ Six to ten middle tail-feathers almost wholly black; the
rest without black ends. ♂ with a nuchal collar of rufous or
buff, and without rufous on the wings.
2. P. lapponicus. ♂. Head, all round, and jugulum, deep
black; a post-ocular stripe, running downward behind the
black jugular patch, and entire lower parts from the jugulum,
white. Nuchal collar chestnut-rufous. ♀ with the black areas
merely indicated by a dusky clouding, and merely a tinge of
rufous round the nape. _Hab._ Circumpolar regions; south in
winter into the United States.
3. P. pictus. ♂. Head above and laterally deep black,
bordered anteriorly and below with white; a post-ocular
stripe, and an ovate auricular spot of the same. Nuchal
collar and entire lower surface bright buff. ♀. Pale
grayish-buff, darker above; above distinctly, and on the
jugulum obsoletely, streaked with black. _Hab._ Interior
plains of North America, north to Arctic Ocean.
4. P. ornatus. ♂ Head above, and whole breast and abdomen,
black; a superciliary stripe, side of head, chin, throat,
anal region and crissum, white; nuchal collar rufous. ♀
hardly distinguishable from that of _P. pictus_.
_a._ Lesser wing-coverts brownish-gray; black feathers of
breast, etc., without rufous edges. _Hab._ Interior plains
of United States … var. _ornatus_.
_b._ Lesser wing-coverts black; black feathers of breast,
etc., with rufous edges. _Hab._ Southern plains of North
America, and table-land of Mexico … var. _melanomus_.
_b._ Only two middle tail-feathers almost wholly black; the
rest with black ends. ♂ without a nuchal collar of rufous or
buff, and with rufous on the wings.
5. P. maccowni. ♂. Crown, and a broad crescent on the
jugulum, black; rest of head and neck ashy, approaching white
on the throat and over the eye; beneath white, above
grayish-brown, streaked with black; middle wing-coverts
rufous. ♀. Above yellowish-umber, beneath yellowish-white;
thickly streaked above, unstreaked beneath. No rufous on
wings, and no black on head or jugulum. _Hab._ Plains, from
Texas, northward.
There seems to be no special reason for subdividing this genus,
although this has been done,—_P. nivalis_ being alone retained in
_Plectrophanes_; _P. maccowni_ forming the type and sole member of the
genus _Rhyncophanes_ (Baird, 1858), and the rest coming under
_Centrophanes_ (Kaup). The characters upon which these are based are
very trivial, being mainly the varying degree of size of the bill and
length of the hind claw. In this latter respect there is too much
individual variation in the same species to admit of this being
available as a specific, much less as a subgeneric character, while
the size of the bill is not of more than specific importance.
Plectrophanes nivalis, MEYER.