106 NATURAL HISTORY IBirds. 



Otherwise be excellent ; but these are invincible obstacles to 

 their being used to these purposes, as no method has yet been 

 hit upon to clear them from the smell and dampness. 



The taist6 build in holes of the earth ; like the rest lays but 

 one egg. 



These birds are found in the winter-time almost wholly gray, 

 and others spotted about the head, neck, and back, with that 

 colour ; but whether they change colour in winter, and put 

 on this as the dress of the season, or if it is the last year's 

 brood not yet arrived at their proper colours, I am uncertain ; 

 one thing I am certain of, that I have seen them of both co- 

 lours late in the winter, and early in the spring, so that, in 

 my opinion, the change is not universal, or perhaps it is but 

 in the hardest winters where this happens in general *. 



Before I dismiss this genus, I must take notice of one par- 

 ticular which I have often observed, and no doubt has been 

 so by others before now, and this is, that all these birds make 

 use of their wings below water in the same manner as a swim- 

 mer uses his arms, the strokes of which answer to those of his 

 legs ; just so the auk, the puffin, the guillemotes, and no doubt 

 the divers use their wings, the strokes of which exactly cor- 

 respond with those of their feet, and by this means make vast 



* The following particular makes me imagine it the young brood that are thus 

 coloured : The legs and feet of the speckled individuals are of a dirty brown, 

 whereas the old birds have these uniformly a very deep orange ; and I believe it is 

 yet unobserved, that birds having once acquired their growth and colours, ever 

 change these of their bare parts. 



