38 



PROCEEDINGS OP THE ACADEMY OP 



of Temminck, PL Color. 200, which is Alca camlschatica Lepechin Bona- 

 parte, Synopsis, 1828, p. 426.— Id. Compt. and Geog. List. 1838, p 66. 

 Vigors, Zool. Voy. Bloss., 1839, Orn. p. 33. Gray, Gen. B., iii. 1849, p. 638. 

 PhahriH {Simorhynchus) cristaldla. Cassin, Baird's B. N. A. 1858, p. 906. 

 Tylorhaniphus cristalellus, Brandt, Bull. Acad. St. Petersb. ii, 1867 p. 348. 

 Pknleris superciliata, Audubon, Orn. Biog. pi. 402 ; oct. ed. pi. 437. Not 

 Mormon sujierciliosa Licht., nor Phaleris superciliosa Bonap.,which refer to 

 Alca camlschatica Lepechin. 



Asiatic and American coasts and islands of the North Pacific, to Behrino-'s 

 Straits ; perhaps into the Arctic Ocean.. Kamlschatka and Behrino-'s Straits, 

 (Mus. Acad. Phila.) Japan, and north-west coast of America, (Mus. Smiths. 

 Inst.) Not known to occur on the American coast so far south as Washing- 

 ton Territory, U. S. 



Bill surpassing that of all other spe- 

 cies of the genus in the extent and di- 

 versity of the irregularities of its sur- 

 face and contour; these irregularities 

 chiefly centered in the base and com- 

 missural edges, and produced by the 

 addition of a supernumerary corneous 

 element to the base of the upper man- 

 dible just at the angle of the rictus, as 

 well as the expjtnsion and projection 

 upwards and outwards of the sides of 

 the lower mandible towards and at its 

 base. Bill, except in the length of its 

 unfeathered commissure, rather short 

 and wide, the length of culmen scarcely 

 surpassing the width of bill at its 

 base. Upper mandible with the cul- 

 men short and regularly very convex 

 from base to tip, which latter is rather acute, and slightly overhangs the 

 lower mandible : its tomial edge extremely sinuate and irregular, lightly 

 notched just behind the tip, at the base widened and somewhat everted, for 

 the reception of the cutting edge of the lower mandible ; lower mandible not 

 nearly' so deep as the upper, somewhat ascending towards the tip, which 

 latter is slender and acute ; the gonys short, perfectly straight, moderately 

 ascending, the sides of the lower mandible elongated, everted, their tomial 

 edge elevated and dilated at the base, posteriorly corresponding in contour to 

 the antero-inferior outline of the supernumerary piece. The latter is a sub- 

 circular or subquadrate corneous plate, slightly concavo-convex, wedged in 

 between the bases of the tomial edges of the two mandibles, and forming the 

 angle of the rictus ; in color and texture it resembles the rest of the bill, of 

 which it is a true component element. Nasal fossae small and inconspicuous, 

 not deeply furrowed, filled in by corneous substance like the rest of the 

 upper mandible; the nostrils small, short, linear-oblong, placed close by 

 the tomial edge of the mandible, overhung by an arched and much dilated 

 corneous scale. Feathers extending on culmen to a point op])osite the angle 

 of the gonys, thence descending perpendicularly along the sides of the bill, 

 just past but not touching the posterior extremity of the nostrils ; thence fol- 

 lowing the sinuosities of the commissural edge of the upper mandible to the 

 supernumerary piece, and around the border of the latter,* but not encroaching 

 upon it. Interramal space of lower mandible densely feathered; but no 

 feathers encroach upon the sides of the lower mandible, contrary to the usual 

 rule in this group. 



* This supernumerary corneous element is not attached by its whole surface to thesub- 

 cumbent bone; but a part of its upper border is free and projects a little away from the 

 sliull. The fossa down behind this free raised border is fully feathered. 



[Jan. 



Fig. 1 .—Simorhynchus cristatellus, (Pallas.) 

 Nat. size. 



