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BRITISH BIRDS, 
THE BLACK-BILLED AUK. 
(Alca Pica, Lin . — Le Petit Pingouin, Buff.) 
These birds weigh from sixteen to twenty ounces, 
and measure in length from fifteen to sixteen inches, 
and in breadth from twenty-four to twenty-eight. The 
bill is black, ' compressed, and slightly ridged and fur- 
rowed on the sides, but more or less so in different sub- 
jects, and some of them have a white line across each 
mandible, while others have the bill nearly quite plain 
and smooth ; an obscure white line extends from the 
upper mandible to the eye, behind which are a mixture 
of dark brown and dirty white feathers, obscurely di- 
vided to the hinder part of the head ; the inside of the 
mouth is yellow; irides hazel; the upper part of the 
head, and a streak below each eye, are black, as are 
also the whole of the upper parts of its silky plumage, 
including the wings and the tail, excepting the tips and 
