LARINJE. CETOSPARACTES. 
251 
and disappear in October. They nestle in vast numbers on 
high maritime cliffs, generally such as are frequented by auks, 
guillemots, and other sea-birds. These breeding-places are 
much more numerous in Scotland than in England. The 
nests, which are generally placed on the lower parts of the 
cliffs, are bulky, formed of grass and sea-weeds, and contain 
two or three eggs, of a broadly oval form, two inches and a 
twelfth in length, an inch and a half in breadth, pale yellow- 
ish-grey, greenish-white, or light olive-green, spotted and 
dotted all over with dark-brown and pale purplish-grey. The 
cry of this bird is clear and rather sharp, resembling the syl- 
lables Kittida , or Kittiweea. It feeds on small fishes, which 
it picks from the water, hovering with elevated wings, as well 
as occasionally Crustacea and small shellfish. It walks little, 
and not with ease, owing to the shortness of its legs ; but has 
an easy and buoyant flight. 
Annet. Tarrock. 
Larus Kissa, and tridactylus, Linn. Syst. Nat. i. 224.— 
Larus tridactylus, Lath. Ind. Ornith. ii. 817. — Larus tridac- 
tylus, Tcmm. Man. d’Ornith. ii. 274. — BIssa tridactyla, Kitti- 
wake, MacGillivray, Brit. Birds, v. 
GENUS CLII. CETOSPARACTES. WHALE-BIRD. 
The “ Ivory Gull” is the only known species of this ge- 
nus, which is distinguished by the short robust bill, very 
short rough tarsi, and crenated interdigital membranes. 
Body moderate ; neck of ordinary length ; head rather 
large, ovato-oblong, anteriorly narrowed. Bill shortish, 
robust, compressed, straight ; upper mandible with the dor- 
sal line somewhat concave at first, then arcuato-declinate, 
the ridge broadly convex, the lateral sinus rather short, wide, 
and feathered ; the nostrils medio-basal, linear-oblong, wider 
anteriorly, covered above and behind with a sloping, thin- 
edged plate, the edges thin, direct, the tip obtuse, very 
slightly prolonged ; lower mandible narrower, compressed, 
with the intercrural space rather long and narrow, the low T er 
outline of the crura straight, forming a very slight promi- 
nence at the commissure, the dorsal line ascending and almost 
straight, the edges thin and somewhat inflected, the tip 
narrow’, rather obtuse ; the gape-line commencing beneath 
the eyes. Legs very short ; tibia bare to a small extent ; 
tarsus very short, little compressed, covered anteriorly with 
