io6 
at.i.en’s naturalist’s library. 
•rilE TRUE RAZOR-BILLS. GENUS ALCA. 
AIca, Linn. Syst. Nat. i, p. 210 (1766). 
Type, A. torda, Linn. 
1 he Razor-bills belong to the group of Auks which have a 
sulcated or grooved bill and exposed nostrils, the latter not 
being encroached upon by the feathering of the base of the 
bill, as is the case with many genera of the himily. In the 
case of the Razor-bills the nostrils are exposed, and situated at 
the end of a triangular base on the mandible, but they are not 
separated by_a ridge from the feathers which encroach on the 
base of the bill, though there is a swollen ridge at the base of 
the lower mandible, anterior to the nostril. The Great Auk is 
merely a gigantic form of Razor-bill, with a heavier body and 
feebler wings than its more active congener. Aka torda, so 
that while the latter survives to the present day in thousands 
the Giant Razor-oill, as the “ Great Auk ” ought more jiroperly 
to be called, has succumbed to circumstances and become 
extinct. 
In addition to the characters given above, the Razor-bills 
differ from the Grrat Auk (m/rd, p. in) in the possession of 
fully developed wings, which reach nearly to the end of the 
tail. They have also well-marked grooves on the bill. 
The typical species, A. torda, is the only representative of 
the genus at the present day. 
I. THE RAZOR-BILL. ALCA TORDA. 
Aha torda, Linn. Syst. Nat. i. p. 210 (1766): Dresser B 
Eur. viii. p. 557 , pl- 619 (1877); B.O.U. I.ist. Brit! b! 
p. 205 (1883); Saunders, cd. Yarrell’s Brit. B iv p ss 
(1884); Seebohm, Hist. Brit. B. iii. p. 37., (i 880 ' 
Saunders, Man. Brit. B. p. 679 (1889); Lilford, Col. 
Brit. B. part xii. (1890). 
Vtama 7 ua torda, Linn. ; Macgill. Brit. B. v. p. 346 (1852). 
[Plate CIV.) 
Nestilng.—Covered with dense sandy-brown down, mottled 
with black bases to the feathers ; the crown of the head and 
sides of face and neck more hoary-grey , cheeks and throat 
