184 BIRD GALLERY. 
No. 128. BLACK-HEADED or LAUGHING GULL. 
(Larus ridibundus.) 
The dark brown hood, from which this species derives its somewhat 
inappropriate name, is assumed in spring, but disappears after the 
autumn moult. It is a common resident on the coasts of the British 
Islands during the colder months of the year, but in spring resorts to 
its breeding-places, where it congregates in large numbers. These “ gul- 
leries,”’ as they are called, are formed in marshy localities, or on inland 
lakes,and some, like that on Scoulton Mere in Norfolk, have been used for 
centuries. The nest is made of sedge, flags, ete., and placed on clumps 
of rushes or on the ground. Three or occasionally four eggs, varying 
greatly in colour and markings, are laid towards the end of April, and 
in many places are regularly collected for the market. This Gull is a 
useful friend to the farmer, feeding for the greater part of the year on 
grubs and other noxious insects. 
Inverness-shire, May. 
Presented by Lord Lovat. 
No. 129. IVORY GULL. (lagophila eburnea.) 
This Arctic species is an occasional wanderer to the coasts of the 
British Islands. About thirty-five examples have been recorded and of 
these rather more than half appear to have been adults. Two is the 
full number of eggs laid. 
Cape Mary Harmsworth, Franz-Josef Land, 7th of August. 
Presented by F. G. Jackson, Esq. 
No. 130. COMMON TERN. (Sterna fluviatilis.) 
This well-known “ Sea-Swallow ” reaches our coasts towards the end 
of April and returns to the south between August and October. Its 
numerous breeding-stations are scattered along the coasts of the British 
Islands, as well as on inland freshwater lochs. The food consists 
principally of small fish, sand-eels, shrimps, and other crustacea, and, like 
the Arctic Tern, it may constantly be seen plunging headlong into the 
sea in pursuit of its prey. The eggs, which vary greatly in colour and 
markings, are two or three in number, and are deposited in a shallow 
depression in the sand or among shingle, dry seaweed, and short 
herbage ; many pairs of birds sometimes nesting within a small area. 
Kent, June. 
Presented by Colonel Willoughby Verner. 
