1877.] 151 [Barrows. 



I am much indebted to Prof. Alpheus Hyatt for assistance and 

 suggestions during the preparation of this paper, and especially to 

 Mr. J. A. Allen, of the Museum of Comparative Zoology, for his 

 kind review and criticism of the whole. 



Dr. Coues's definition of the Family Alcidce (Monograph of the 

 Alcidce, Proc. Phil. Ac. Nat. Sci., 1868, p. 14) is so brief, concise, 

 and satisfactory, that I give it entire. With this exception the de- 

 scriptions are all my own. 



Descriptions of Genera and Species. 



Family ALCIDCE. 



" Three-toed, short-winged, short-tailed Natatores with lateral 

 nostrils." — Coues. 



Genus Fratercula Brisson. 



Bill much compressed, upper mandible never free from irregular- 

 ities in the adult; usually more or less grooved on the sides, bending 

 over the lower at tip; culmen very convex; nostrils linear, situated 

 in the basal half of bill, and opening just above the commissure, 

 entirely free from feathers and separated from those of the face by a 

 narrow, horny ridge or ribbon, from which the feathers seem to have 

 receded, leaving the marks of their insertion in the shape of small 

 dots which are more or less distinct in the different species, and 

 especially on the posterior side of the ridge. This horny belt runs 

 from the commissure to the culmen on both sides. Tarsus partly 

 scutellate in front. Inner claw very sharp and much curved (evi- 

 dent, but not so marked in F. monocerata). Tail squarish, of sixteen 

 feathers. Wings as usual. Total length thirteen to sixteen inches. 



1. Fratercula cirrhata. 



Alca cirrhata Pallas, 1769. Lunda cirrhata Pallas, 1811. Mormon 

 (Lundd) cirrhata Bonap., Cassin. Mormon cirrhata Aud. Fratercula 

 cirrhata Stephens, Vieillot, Gray. 



Largest of the genus; bill very much compressed, three-fourths as 

 high at base as long; lower mandible without vertical grooves, but 

 with a longitudinal one beginning near the base close to the gonys, 

 and extending forward half an inch or more parallel to the lower 

 edge of the mandible, and then ending abruptly. Upper mandible 

 with three vertical, curved grooves with their concave sides toward 

 the point of the bill. An accessory corneous piece of about an inch 

 in length and somewhat the shape of a date " stone," extends along 



