ALCINiE. URIA. 
211 
of small fishes, mollusca, Crustacea, and other marine 
animals. Their flesh is very dark coloured, rank, and 
unpalatable. Seven species rank as British, and of these 
four exist in prodigious numbers in the localities suited 
for them. 
GENUS CXL. URIA. GUILLEMOT. 
The transition from Colymbus to Uria is in some respects 
not great, the bill being very similar in both genera. In 
Uria it is generally shorter than the head, straight, stout, 
compressed, tapering, acute ; the upper mandible with the 
dorsal line slightly arched, the ridge narrow, the sides slop- 
ing, the edges sharp and inflected, the tip a little decurved 
and slightly notched ; the nasal groove broad and feathered ; 
the lower mandible with the angle rather long and narrow, 
the dorsal line ascending and straight, the back very narrow, 
the sides nearly flat, the edges sharp and inflected, the tip 
acute. Mouth rather wide ; palate flat, with five prominent 
lines anteriorly ; tongue slender, trigonal, tapering, pointed ; 
oesophagus wide, its lower part and the proventriculus much 
dilated ; stomach moderately muscular, with a dense, plaited 
epithelium ; intestine long and rather wide ; coeca moderate. 
Nostrils sub-basal, longitudinal, linear. Eyes of moderate 
size. Apertures of ears very small. Head large, ovate ; 
neck short and thick ; body full, rather depressed. Feet 
short, placed far behind ; lower part of tibia bare ; tarsus 
short, stout, compressed, scutellate in front ; hind toe want- 
ing, anterior toes of moderate length, the third longest, the 
fourth little shorter, scutellate, connected by entire webs ; 
claws rather small, arched, compressed, rather acute. Plum- 
age dense, very soft, blended ; wings rather small, narrow, 
acute ; primary quills curved, the first and second longest ; 
tail very short, rounded, of twelve or more feathers. 
The Guillemots assume a nearly erect posture in standing, 
are incapable of walking efficiently, but swim and dive with 
the greatest dexterity. Their flight is low, direct, and ra- 
pid. They breed on rocky headlands and islands, assem- 
bling for that purpose in vast numbers. Most of them lay 
a single, very large, pyriform egg, marked with dusky lines 
