GULL. NATATORES. LARUS. 489 
any of the other species by the whiteness of the middle part 
of its primary quills. 
PLATE 92° Represents this bird of the natural size, and in 
the summer or nuptial plumage. 
Head, chin, and throat, dark hair-brown. At the poste- General 
rior angle of the eye is a spot of white. Eyelids and cy ‘ 
bill deep crimson-red, the latter measuring one inch and summer 
two-eighths from the forehead to the tip. Mantle, sca- Plumage. 
pulars, and lesser wing-coverts pale pearl-grey. Outer 
border of the wings, greater coverts, rump, and tail, 
pure white. First quill-feather having the lower part 
of the cuter web, the tip, and outer margin of the inner 
web, black; the rest of it white. The three next quills 
have the greater part of their outer webs white; their 
ends (except the extreme point, which is white) and 
half their inner webs, black, passing into blackish-grey 
near the bases of the feathers. ‘The remainder of the 
quills are pearl-grey, marked with black, as in the pre- 
ceding. Under plumage white, having, in some speci- 
mens, a slight rosy tint. Legs and toes deep arterial 
blood-red. 
In winter, or after casting the hair-brown hood, the head Winter 
and throat are of a pure white, except a small spot of os 
blackish-grey at the anterior angle of each eye, and an- 
other of the same colour upon the auriculars. The bill 
and legs also lose a little of the intensity of hue that 
distinguishes them in summer. 
The young of the year, previous to the autumnal moult, Young. 
have the head and occiput of a yellowish-brown, and the 
auriculars and space behind the eyes white. Lower 
part of the neck and under plumage white, with a faint 
blush of pink. Mantle, scapulars, and lesser wing-co- 
verts broccoli-brown, the feathers being edged with pale 
yellowish-brown. Lower part of the back, and basal 
part of the tail, white, with a broad bar of clove-brown 
