GREAT NORTHERN DIVER. 
213 
the tip of the bill to the end of the tail, and four feet six 
inches in breadth ; the bill is strong*, of a glossy black, and 
four inches and three quarters long to the corner of the mouth ; 
the edges of the bill do not fit exactly into each other, and are 
ragged, the lower mandible separates into two branches, which 
are united by a thin elastic membrane, and are easily movable 
horizontally, or receding from each other, so as to form a wider 
gap to facilitate the swallowing of large fish ; tongue, bifid ; 
irides, dark blood red ; the head and half of the length of -the 
neck, are of a deep black with a green gloss, and purple re- 
flections ; this is succeeded by a band consisting of interrupted 
white and black lateral stripes, which encompasses the neck, 
and tapers to a point on its fore part, without joining, — this 
band measures about an inch and a half in its widest part, and, 
to appearance, is not continuous on the back part of the neck, 
being concealed by some thick, overhanging, black feathers, 
but, on separating the latter, the band becomes visible : the 
feathers which form these narrow stripes, are white, streaked 
down their centre with black, and, what is a remarkable pecu- 
liarity, their webs project above the common surface ; below 
this, a broad band of dark glossy green and violet, which is 
blended behind with the plumage of the back ; the lower part 
of the neck, and the sides of the breast, are ribbed in the same 
manner as the band above ; below the chin, a few stripes of 
the same ; the whole of the upper parts are of a deep black, 
slightly glossed with green, and thickly spotted with white, in 
regular transverse or semicircular rows, two spots on the end 
of each feather — those on the upper part of the back, shoul- 
ders, rump, and tail-coverts, small and roundish, those on the 
centre of the back, square and larger ; those on the scapulars 
are the largest, and of an oblong square shape | the wing-fea- 
thers and tail are plain brown black, the latter composed of 
twenty feathers ; the lower parts are pure white, a slight 
dusky line across the vent ; the scapulars descend over the 
wing when closed, and the belly feathers ascend so as to meet 
them, by which means every part of the wing is concealed. 
