[ Cases 
25, 26.] 
46 BIRD GALLERY. 
come two diminutive forms of Guillemot represented by the Ancient 
Auk (Synthliborhamphus antiquus) (889) and the Marbled Guillemot 
(Brachyrhamphus marmoratus) (898). Of the true Guillemots (Uria) 
two species, the Common Guillemot, Marrot, or Murre (U. troile) (402), 
and the Black Guillemot or Tystie (U. grylle) (400), are British breeding- 
birds ; the Bridled Guillemot (U. troile, var ringvia) (401) being generally 
regarded as merely a variety of the former, though some consider it a 
distinct species. It is not nearly so numerous as the common form and 
always occurs in company with it. The wonderful range of colour and 
markings in the eggs laid by the Common Guillemot is well illustrated in 
the Case exhibited on the right-hand side of the staircase in the Central 
Hall. The set of specimens showing the seasonal changes of plumage 
in the Black Guillemot deserves special notice. Brtinnich’s Guillemot 
(U. lomvia) (408), distinguished chiefly by its stouter bill and by having 
the basal part of the upper mandible naked, occasionally visits our 
coasts as a straggler from the Arctic Ocean. Another regular winter 
visitor to Britain is the Little Auk or Rotche (Alle alle) (404). The 
Razor-Bill (Alcea torda) (405) is chiefly interesting on account of its 
resemblance and probable relationship to the Great Auk, which will be 
found immediately below. The Great Auk or Gare-fowl (Plautus 
impennis) (406) [ Pl. V.] is a bird of quite exceptional interest, being now 
extinct. As may be seen from its diminutive wings it was quite unable 
to fly, and its extermination was due largely, if not entirely, to the agency 
of man. The last colony of this bird inhabited the islands near Iceland 
and was finally exterminated in 1844. Specimens of this bird and its 
eggs are now regarded as great treasures. 
Order XI. LARIFORMES. Goutt- ripe, 
The Gulls, Terns, and Skuas which make up this Order are closely 
allied on the one hand to the Auks and on the other to the Plovers 
which follow, and some zoologists regard these three groups as forming 
but a single Order. Superficially the Gulls bear some resemblance to the 
Petrels, but may readily be distinguished from the latter by their slit- 
like nostrils. From the Plover-tribe they may be recognised by their 
webbed feet, and from the Auks by their long wings and tail and by 
the carriage of the body, which is horizontal instead of nearly vertical. 
The predominating colour in the adult birds is white, with a mantle 
varying in shade from grey to black. The young differ from the adults, 
being usually mottled with brown or black, and the nestlings are 
covered with beautifully patterned down. From one to four eggs are 
laid, usually brown or green heavily blotched and spotted with brown, 
black, and pale hlac. 
