NORTHERN THREE-TOED WOODPECKER. 
427 
gonal ; the tongue is somewhat shorter than that of other spe- 
cies of the genus ; the bristly feathers at the base of the bill 
are very thick and long, a provision which nature has made 
for most arctic birds ; in this they measure half an inch, and are 
blackish, white at base, somewhat mixed with reddish white ; 
the irides are bluish black ; the whole head and neck above 
and on the sides, back, rump, scapulars, smaller wing and tail- 
coverts, constituting the whole upper surface of the bird, of an 
uniform, deep, glossy black, changing somewhat to green and 
purple, according to the incidence of light ; the feathers of the 
front are tipped with white, producing elegant dots of that 
colour (which perhaps disappear with age) ; the crown of the 
head is ornamented with a beautiful oblong spot one inch in 
length, and more than half an inch broad, of a bright silky golden 
yellow, faintly tinged with orange, and the feathers in this 
place very fine, and somewhat rigid ; they are black at their 
base, and marked with white at the limits of the two colours ; 
the base of the plumage elsewhere is uniformly plumbeous 
ash : each side, from the corner of the mouth, arises a broad 
white line, forming a white space before the eye, prolonged 
on the neck ; beneath this there is a black one, which, passing 
from the base of the lower mandible, joins the mass of black 
of the body ; a tuft of setaceous white feathers advances far 
upon the bill beneath ; the throat, breast, middle of the belly, 
and tips of the under tail- coverts, are pure white; the sides 
of the breast, flanks broadly, and base of the tail-coverts, 
and even of some of the belly feathers, are thickly waved 
with lines of black and white, as well as the femoral and short 
tarsal feathers : in very old birds, as the one represented in 
the plate, these parts are considerably less undulated, being 
of a much purer white ; the wings are five inches long, reach- 
ing two-thirds the length of the tail ; the spurious feather is 
exceedingly short, the first primary hardly longer than the 
seventh ; and the four following subequal and longest ; the 
smaller wing-coverts, as mentioned, glossy black ; all the other 
upper coverts, as well as the quills, are of a dull black, the 
