2306 TUBE-NOSED BIRDS, DIVING BIRDS, PENGUINS 



of considerable length, and the head is of a uniform smoky brown. It is replaced 

 in the Pacific by a somewhat larger form, known as the Californian guillemot. Both 

 in the Atlantic and Pacific there are also certain guillemots, like the one in the fore- 

 ground of the cut, characterized by the presence of a white streak extending back- 

 ward from the eye, and a white ring round the eye itself. Formerly regarded as 

 indicating a distinct species, these ringed guillemots, as they are commonly called, 

 are now generally considered to be merely sports. Pallas' s guillemot, of Behring 

 Sea and other parts of the North Pacific is the largest representative of the second 

 modification of the group, in which the beak is much shorter and deeper than in the 

 preceding, while the nape of the neck and back of the head are black like the back. 

 A portion of the base of the cutting edge of the mandible is light colored. Finally, 

 we have the so-called Briinnich's or polar guillemot {U. bruennichi), of the North 

 Atlantic and Arctic Oceans, in which the size is smaller, and the whole of the cut- 

 ting edge of the upper mandible yellowish white. Mr. Seebohm considers, however, 

 that Briinnich's guillemot is so inseparably connected by the Californian form with 

 the common guillemot, as to render it impossible to regard them as more than varie- 

 ties of a single species. Whatever diversity of opinion may obtain as to the dis- 

 tinctness of the above-mentioned forms from the common guillemot, there can be 

 none as to that of the black guillemot ( U. grylle), which is referred, indeed, by some 

 writers to a separate genus. It is a smaller bird than the common guillemot, from 

 which it is at once distinguished by the whole of the under parts being black in the 

 summer dress, the beak being relatively short. Typically an inhabitant of the North 

 Atlantic, it is represented in the circumpolar seas by a variety distinguished by the 

 larger size of the conspicuous white patch on the wings. In the North Pacific it is 

 replaced by the pigeon guillemot (U. columba), characterized by the under surface 

 of the wing being gray, instead of smoky white. The typical form of this species 

 has a large white wing patch; but there are two varieties (carbo and motzfeldi}, sev- 

 erally distinguished by the presence or absence of white on the head, in which the 

 wing is uniformly black on the outer side. 



All the guillemots are very similar in their mode of life, being essentially 

 oceanic birds, which only visit the rocks during the breeding season, and are only 

 found inland when driven there by stress of weather; while they are markedly soci- 

 able and gregarious. Their food consists of fish, supplemented by various crusta- 

 ceans, the common species being especially partial to the fry of herrings and pilchards, 

 which are captured at night in the open sea. Rapid, though heavy and labored in 

 its flight, the common guillemot is enabled to reach the summits of almost inaccess- 

 ible cliffs for the purpose of breeding, where, as in the Fame islands and at Flam- 

 borough, it congregates in myriads. On the ledges of the precipitous cliffs near 

 Bempton another noted breeding place the guillemots, are sometimes so densely 

 crowded together as to remind one of a swarm of bees. The breeding season in 

 Britain commences in May and lasts till August; and while the other species agree 

 with the rest of the family in laying but a single egg, the black guillemot deposits 

 two. The eggs may be laid either on the bare ledges of rock or in fissures; and 

 while at times several may be found together, at other times they lie singly. In 

 coloration, guillemot's eggs are remarkable for their extraordinary variability. 



