512 THE DIVING BIRDS — PTGOPODES. 



which are a rictal plate ami a broad, curved, posteriorly truncate shield covering the lateral hase 

 of the uuindible. Forehead ornamented by an upright recurved tuft of slender feathers, the tips of 



S. cristatellus. 



which overhang the bill ; head farther ornamented by a postocular series of slender white 

 filamentous feathers. Plumage plain — uniform dusky above, gray bek)W. 

 A single species (S. cristatellus) belongs to this genus, as here restricted. 



Simorhynchus cristatellus. 



THE CRESTED AUK. 



Alca crhfnfeUn, Pall. Spio. Zool. V. 17(39, 20, pi. 3 and pi. 5, figs. 7, 8, 9. — Gmel. S. N. I. ii. 



1788, .'35-2, no. 7. 

 Simorhiinclms cristntellux, ''lslvAU\y.y\" \\<^^ XV. Com\^i. Enid. XLII. 1856, 774. — CouES, Pr. Ac. 



Nat. Sci. Philad. 1868, 37 ; Key, 1872, 312 ; Check List, 1873, no. 622 ; ed. 2, 1882, no. 859 ; 



Elliott's Alaska, 1875, 206. — RiDOW. Norn. N. Am. B. 1881, no. 748. 

 Phnlcn's crh/atellus, STF.vuEysi, Gl-u. Zool. XIII. 1825, 47, pi. 5. — Cass, in Baird's B. N. Am. 



1858, 906. — Baiud, Cat. X. Am. 15. 1859, no. 719. 

 Phaleris supcrcili'dn, Aun. Orn. Biog. pi. 402 ; B. Am. YII. 1844, jil. 437 (not Mormon superciliosa, 



LlciiT., = Alca pi/r/mcva, Gal). 

 Uria dubia. Pall. Zoog. P>osso-As. II. 1826, 371, pi. 87 (^ young). 

 Simorhynchus cluhms, Coues, Pr. Ac. N^at. Sci. Pliilail. 1868, 40. 

 Alea fcfrnruJa, Pall. Spic. Zool. V. 1769, 23, pi. 4, and ]il. 5, figs. 10, 11, 12. —Gmel. S. N.I. ii. 



1788, 552, no. 8. 

 Phaleris tctramla, Cass, in Baird's B. N. Am. 1858, 907. — Baird, Cat. N. Am. B. 1859, no. 720. 

 Simorhynchus tetraculus, Coues, Pr. Ac. Nat. Sci. Philad. 1868, 43, fig. 9 ; Key, 1872, 342. 



IIab. Coasts and islands of the North Pacific, from Kadiak and Unalashka through the 

 Aleutian chain to Kamtschatka and Northern Japan ; north to Prybilof Islands. 



Sp. Char. Adult, hreeding-drcss : Basal pf»rtion of the bill covered with complicated super- 

 numerary pieces, the most conspicuous of whicli is a <letaclied semicircular concave plate situated 

 just above the rictus. U]iper ]iarls dusky blackish ; lower parts uniform smoky gray, shading 

 insensibly into the blackisji df the upper parts. On the forehead a curled crest of narrow dusky 

 lirown feathers, curved forward in the gr(;ater part of a circle ; behind the eye, extending thence 

 back over the auriculars, a streak of narrow acicular white feathers. Bill bright orange-red, the 

 end pale horn-color ; iris white ; legs and feet dusky in the dried skin. Adult, in printer (= Alca 

 tetracnla, Pallas) : Similar in plumage, even to the crest and wdiite auricular filaments ; but bill 

 very difierent, owing to the loss of the su]X'rnumerary basal pieces, being much smaller, smooth, 

 and destitute of the rictal shield, the broad expansion of the mandibular rami and nasal shield ; 



