ALUIDyE — THE AUKS — CEPPHUS. 497 



Comparative proportions. 

 Length of the bill to the nostrils, 

 Length of wing, 

 Length of tarsus, 

 Length of middle toe, with claw, 

 Length of the claw, 

 Length of the rectrices, 

 (Pallas, 1. c, translation.) 



According to Von Schrenck ("Reis. Ainurl." I. 18(50, p. 497), there is some variation in the 

 amount of the white on the head, especially around the base of the bill, where in some specimens 

 there is scarcely any trace whatever of this color. The single example in the National Museum 

 collection (a head from Japan, collected by Dr. W. Stiinpson) agrees exactly with Pallas's descrip- 

 tion, as above, in having the feathers all round the base of tin' bill distinctly white. The measure- 

 ments of this specimen are as follows : Culmen, 1.70 ; commissure, 2.10; gonys, .80; side of 

 mandible to malar apex, 1.55 ; depth at base, .50 ; width, .38. This head is of a dull grayish-fuligi- 

 nous, darker on the pileum and lower pari of neck, and becoming dull white at the base of the bill 

 all round), as well as around the eve-, and thence backward, as an ill-defined streak, along the 

 upper edge of the aurieulars. The under side of the head, as well as the greater extent of the 

 lateral portions, is dull smoky grayish, this color fading rather gradually into the white, which is 

 abruptly defined only above the eyes, where the dusky color of the crown forms a marked contrast. 



I can find no mention of the living presence of this species either on any por- 

 tion of the American coast or in the Aleutian Islands ; nor is there any evidence 

 that it has a claim to be retained in the avi-fauna of North America. Its habits — ■ 

 in regard to which I have no notes — are probably nearly identical with those of 

 C. grylle. and C. columba. This bird is not uncommon in the summer in Yezo, Japan 

 (Swinhoe, " Ibis," 1875). 



Cepphus Motzfeldi. 



MOTZFELD'S GUILLEMOT. 



Vria Motzfd&i, Benicken, Isis, Aug. 1824, 889. 



Cepphus Motzfeldi, Stejn. Pr. U. S. Nat. Mils. 1881. 



Vria unicolor, Faber, Isis, Sept. 18-21, 981. — Brehm, Isis, 1826, 9S8 ; Handb. Fog. Deutschl. 



1831, 985. — Schleg. Rev. Crit. 1844, 106. — Bp. Compt. Rend. XLH. 1850, 774 ; Cat. Parzud. 



1SS6, 12. 

 Grylle carbo, Bp. Cat. Met. Ucc. Eur. 1842, 82 (not of Pall. 1826). 

 " Una carbo (Brit. Mus. ex Iceland)," Newt. Ibis, 1865, 518 (part). 

 Aka grylle, Schleg. Mus. P.-B. Urinat. 1867, 20 (part). 

 Una grylle, Kuml. Bull. U. S. Nat. Mus. No. 15, p. 104 (part). 



Hab. High North Atlantic (west shores of Cumberland Sound, Greenland, and Iceland). 



Sp. Char. Similar to C. carbo, but without any white or light grayish about the head. Adult : 

 Entire plumage uniform sooty black or dark sooty brown, the abdomen somewhat more grayish. 

 '• Bill black, very compressed, with very prominent gonydeal protuberance, bent tip, and feathered 

 as far as above the nostrils" (Benicken, /. c, translation). Total length, 16 inches 9 lines (Ham- 

 burg measure) ; culmen, 1 inch 9 lines ; bill from angle of mouth, 2 inches 3 lines ; from nostril, 

 1 inch ; tarsus, 1 inch 6 lines. Feet yellowish brown (in dried skin), the webs whitish. 



This bird, which evidently is a distinct, but little known, species, was first described by 

 Benicken from a specimen received by him in 1820 from Greenland. A month afterward the same 

 specimen was re-described by Faber as Uria unicolor, under the supposition that it had not yet 

 received a name. To his description be adds the information that the owner of the bird-rookery on 

 Draugoe, Iceland, had occasionally observed a pair of uniformly dusky Guillemots breeding on the 

 rocks at that place. A specimen similar to Benicken's type was received at the Leyden Museum 

 from Greenland, and is mentioned by Sehlegel in his "Revue critique," as cited above. A third 

 vol. II. — 63 



