454 ALCADM. 



a small indentation or notch in the edge on each side. Nostrils basal 

 lateral, concave, pierced longitudinally, partly closed by membrane, which 

 is also partly covered with feathers. Feet short, placed behind the centre 

 of gravity in the body; legs slender, feet with only three toes, all in 

 front, entirely webbed. Wings short, first quill-feather the longest. 

 Tail short. 



THE birds of this genus, and of the Alcadae in general, 

 bear considerable resemblance to the Divers, both in form 

 and habits ; they are oceanic birds that can swim and dive 

 well, and in this way obtain small fishes of various sorts, 

 or still smaller Crustacea, as food. 



The Common Guillemot is one of the best known of 

 the species, and may be seen in the tide-way of the open 

 sea all round our coast at any season ; but as their numbers 

 are there dispersed over an extensive surface, these birds 

 are best observed during their breeding-season, when they 

 assemble by hundreds, or thousands more frequently, on 

 many of the most extensive and highest rocks and cliffs 

 that bound our sea-girt islands. 



About the beginning of May the Common Guillemots, 

 with many other species of birds, frequenting rocks at that 

 season, to be hereafter described, converge to particular 

 points, where, from the numbers that congregate, and the 

 bustle apparent among them, confusion of interests and 

 localities might be expected ; but on the contrary, it will 

 be found that the Guillemots occupy one station, or line 

 of ledges on the rock ; the Razorbills another ; the Puffins 

 a third ; Kittiwake Gulls a fourth ; whilst the most inac- 

 cessible pinnacles seem to be left for the use of the Lesser 

 Black -backed and the Herring Gulls. Two distinct species 

 scarcely ever breed close by the side of each other. 



The Common Guillemot lays only a single egg, but this 

 is of large size, and very variable in colour, scarcely two 

 being found precisely alike, but generally of a fine bluish- 

 green, more or less blotched and streaked with dark red- 



