436 NATATORES. ALCA. RAZOR-BILL AUK. 



Periodical length as those of the Guillemot, and reaching, when closed, 

 as far as the rump. Like that bird, its flight is rapid, and 

 sustained by very quickly repeated strokes of the pinions, 

 but (unless when making an effort to reach the ledge of rock 

 on which it breeds) always at a low elevation, just clearing 

 even the surface of the water. It is common upon the Eng- 

 lish coast during the summer in its black-headed or nuptial 

 dress, congregating in the same localities, and frequently 

 breeding in company with the Guillemot, which it resembles 

 in general appearance, and also in the change of plumage it 

 undergoes. By many writers, the young as well as the old 

 birds, in the winter clothing, have been described as a dis- 

 tinct species, under the title of Alca Pica; and as MONTAGU 

 decidedly favours this opinion in his Ornithological Diction- 

 ary, doubts are still entertained on the subject, although the 

 subsequent investigations of TEMMINCK, FLEMING, and 

 other distinguished practical ornithologists, have decidedly 

 proved the fallacy of the opinion. The same suppositions 

 that led MONTAGU astray with regard to the Guillemot, ap- 

 pear to have operated in the case of the Razor-bill, viz. that 

 the old birds of both species always retained the black head 

 and neck, and that the English and the southern part of the 

 Scottish coast were the limit of the polar migration of these 

 distinct species; for it is upon these assumptions that his 

 arguments in favour of the separation of each species into 

 two are founded. In the article " Auk, razor-billed," in the 

 Supplement to his Ornithological Dictionary, he also seems 

 to have repeated the mistake that I have previously adverted 

 to under the Guillemot, viz. of describing as a young bird 

 what appears to have been in reality an adult in a state of 

 moult; his description exactly agreeing with specimens I 

 have seen in that state ; and at which period they are some- 

 times unable to fly, from casting their quill-feathers. But it 

 generally happens that, before this change takes place, they 

 have left our shores for more open parts of the ocean, or 

 gone to more southern districts. In winter their place is 



