GIILLEMOT. NATATORES. URIA. 421 



THE above list of provincial appellations, bestowed upon Periodical 

 the Guillemot in different parts of Britain, is a sufficient visitant 

 proof of its general distribution and frequent occurrence. 

 It is in fact (at least during the summer or breeding season), 

 to be found throughout the whole extent of our coasts, con- 

 gregated in large bodies, wherever the shores offer a precipi- 

 tous rocky barrier, or islands occur, affording fit places for , 

 its reproduction. Such are the ledges and clefts of rocks, 

 where these birds incubate close to each other ; making no 

 nest, but each depositing its large solitary egg upon the bare incubation, 

 and often sloping surface, along which it is secured from roll- &c * 

 ing by its conical shape, being very large at one end, and ta- 

 pering rapidly towards the other ; thus, when disturbed, 

 merely describing a circle within its own length. The egg 

 varies in colour and markings, but the prevailing tint is a 

 fine verdigris-green, blotched with brownish-black. White 

 varieties, without or with few spots, also frequently occur. 

 Incubation lasts for a month, and when the young are first 

 excluded, they are covered with a thick down, of a blackish- 

 grey colour above, and white beneath. This gradually gives 

 place to the regular plumage, and in the course of five or 

 six weeks from the time of hatching, they are capable of 

 taking to the water. During the time they remain upon the 

 rock, the parents supply them plentifully with the young of . 

 the herring, and herring-sprats, which form the principal 

 food of this and other species belonging to the Alcadee. Up- Food. 

 on the Northumbrian coast these Guillemots breed in great 

 numbers on the Fern Islands, a locality that has afforded me 

 ample opportunities of attending to their economy, and watch- 

 ing the changes they undergo. They have here selected the 

 summits of three fine isolated pillars, or masses of whinstane 

 (trap-rock), that rise upwards of thirty feet above the level 

 of the sea. Upon these the eggs are laid as close as possible, 

 merely allowing room for the birds to sit upon them, which 

 they do in an upright position. The appearance they make 

 when thus seated in a dense mass, is curious, and the interest 

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