BIRDS — ALCIDAE — CERORHINA MONOCERATA. 



905 



CEROKHINA MONOCERATA, (Pallas,) Cassin. 



The Ilorn.billed Guillemot. 



^Ica monocerata, Pallas, Zoog. Rosso-Asiat. II, 1811, 362. 



Phaleris cerorhynclia, Bonap. Zool. Jour. Ill, 1827, 53. 



Cerorhyncha occ'uUntalis, Bosap. Ann. Lye. N. Y. II, 1828, 428. 



Ceratorkyncha occidentalis, Bonap. Comp. List, 1838, 60.— Arc. Orn. Biog. V, 1839, 104 ; pi. 402. 



CInmerina cornuta, Eschsch. Zool. Atlas, III, 1829, 2 ; pi. .\ii. 



" Cerorhina orienialis, Bonap." Brandt, Bull. Acad. St. Petersburg, I, 1837,345. 



Figures. — Eschscholtz, Zool. Atlas, pi. 12. — Add. B. of Am. pi. 402, fig. 5, oct. ed. VII, pi. 471. 



Sp. Ch — Bill rather large, flattened laterally; upper mandible with an upright iiorny appendage at its base, the top or 

 termination of which is freijuently broken or worn off; angle of under mandible very distinct, and having the appearance of 

 being a distinct piece ; wings moderate, pointed ; tail short, rounded ; legs short, robust. Head and entire upper parts dark 

 fuhginous ; lighter and tinged with ashy on the throat and neck in front ; darker and nearly black on the back and rump. A 

 line of long yellowish white feathers over and behind the eye and another from the corner of the mouth. Under parts of body 

 white ; under wing coverts and sides ashy brown ; bill dark orange ; legs light colored. 



Total length about 15 to 15 1 inches ; wing, 7j ; tail, 2j ; bill to gape, 2 inches. 



Hab. — Northwestern and western coasts of America ; northeastern Asia ; Japan, (Com. Perry's Expedition.) 



This bird, though formerly regarded as very rare, and highly prized by naturalists and 

 collectors, is now frequently brought in the collections of expeditions and travellers, and is 

 apparently of quite usual occurrence on the western coast of North America. It is easily 

 distinguished by the short upright horn at the base of the upper mandible, which, in the 

 majority of specimens, is broken or worn oiF at the tip or end, leaving a hollow upright tube, 

 which we have known persons to mistake for this bird's nostril. This upright horn is not, 

 however, present in all specimens, and may be dependent for its growth or greater development 

 on season or sex. In a very fine specimen now before us, obtained by Mr. William Heine in the 

 island of Jesso, during the voyage of the United States Japan Expedition, there is not a vestage 

 of this appendage. This specimen is labelled as a female, and is alluded to by us in our account 

 of the birds collected by the Japan Expedition, in Vol. II of the Report of Commodore Perry. 



The descriptions of this bird by the Prince Bonaparte, which have been relied on by American 

 naturalists, are very defective, and no measurements whatever are given. This circumstance, 

 in connexion with the fact that this bird has been little known to naturalists, has been the cause 

 of some confusion and difficulty in determining this species. Even the Prince Bonaparte himself 

 seems to have retained but an indistinct recollection of it, when he states that his SagmatorJdna 

 lathami is one-third larger. — (Proc. Zool. Soc. London, 1851, p. 202.) The fact is, there is very 

 little difference in the size of the two species, if such they are, though SagmatorJiina appears to 

 be slightly larger, the Prince Bonaparte giving its total length as IG inches in the description, 

 as cited above. Audubon gives the total length of the present bird as 15i inches, which is very 

 nearly the measurement of the skins now before us, though variously distorted. We regard it 

 as by no means impossible that Sagmatorhina is the young of the present species. 



Oct. 15, 1858. 



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