LARINA. GAYIA. 
239 
tacea, insects, and worms. They are of vagrant habits, 
shifting from place to place according to the abundance 
of food. They walk well, wade into shallows, swim with 
ease, floating most buoyantly ; have a light, wavering, mo- 
derately rapid flight, hover over the water, pat it with their 
feet in stooping, and with up-stretched quivering wings, 
pick up their food. They nestle, often in multitudes, on 
islands and headlands, form a bulky nest, aild lay from 
two to five oval large eggs, of a dull colour, spotted with 
dusky. The young are clothed with close variegated 
down, and can soon walk, but generally remain near the 
nest until fledged, when they always differ in colour from 
the adult birds. The species are all closely allied, but 
may be divided into several genera. The number found 
in Britain is thirteen. 
■GENUS CXLIX. GAYIA. MEW. 
The “ Sea-Mews,” or “ Smaller Gulls,” have a consider- 
able affinity to the Terns. They are birds of rather small 
size, with the body rather light ; the neck moderate, the head 
rather large, broadly ovate. Bill rather long or moderate, 
slender, much compressed, slightly decurved at the end, 
acute ; upper mandible with the nasal sinus rather long, 
narrow, and feathered, the edges very thin, inclinate, the 
tip narow, rather acute, slightly prolonged, with a faint sinus 
on the margins ; lower mandible very much compressed, with 
the intercrural space very long and extremely narrow, the 
commissure forming a slight angle with the dorsal line, 
which is nearly straight, the edges very thin, the tip rather 
acute. Mouth of moderate width ; tongue fleshy, slender, 
tapering ; oesophagus very wide, its walls extremely thin ; 
stomach rather small, oblong, moderately muscular, with 
large tendons, and thick horny epithelium, with very pro- 
minent longitudinal rugae ; intestine of moderate length, and 
very narrow ; coeca extremely small, cylindrical. Nostrils 
linear-oblong. Eyes rather small; eyelids feathered, with 
bare crenulate margins. Aperture of ear of moderate size. 
Legs of moderate length, rather slender ; tibia bare for one - 
