ALCIDJi — T!1K AUKS ~ ALCA. 



473 



Alca balthica, BiiiJNN. Oin. lior. 1704, 25, no. 101 (immature, without white line froin bill to eye). 



Alca unisulcala, Biiii.NN. t. c. no. 102 (young). 



Alca (jlacialis, BiiEiiM, Vbg. Deutschl. 1831, 1004. 



Alca islandica, BiUCii.M, t. c. 1005. 



Alca microrliijnchus, I>iiKii.\i, Vogelf. 1855, 410. 



Hab. Coasts and i«lauds of the North Atkntic, down to about latitude \{f in winter. Japan ? 

 {fide Schlegkl). 



A. torda. 



Sp. Char. Adult, in summer : Head, neck, and upper parts black, the head and neck more 

 fuliginous, and changing to soft, velvety snuff-brown on the under portion of the head and fore- 

 neck ; secondaries narrowly tipped with white ; 

 a narrow white line running from the base of 

 the culnien to the eye. Lower parts, including 

 jugulum, axillars, and lining of the wing, im- 

 maculate white. Bill black, botli mandibles 

 crossed about the middle by a white line ; 

 " inside of mouth gandioge-yellow ; iris deep 

 hazel; feet black" (Audubon). Adult, in 

 winter: Whole under portion of the head, fore- 

 neck, and post-auricular region white ; no white 

 line from eye to bill ; bill without basal lam- 

 ina. Otherwise like the summer plumage. 

 Young : Similar to the winter plumage, but 

 bill smaller, perfectly smooth, and without the 

 white bar across the middle portion. 



Total length, about 17.00 inches ; Aving, 

 8.00 to 8.50; tail, 3.50 ; culmen, 1.25; great- 

 est depth of bill, .90 ; tarsu.s, 1.25 ; middle 

 toe, 1.55. 



Summer adult. 



This is a iiortlieni and Arctic species, abniulant tliroiighout the eastern shores of 

 North America from the highest latitudes to Maine in sunuuer and to Xew Jerse}- in 

 VOL. II. — GO 



