46 



of elongated filiform feathers about the head. Their absence, however, is 

 not to be regarded as a specific character, since it cannot be positively 

 aflirmed that the specimen is fully adult. 



The affinities of the species are clearly with S. tetraculus, which it resem- 

 bles in the small simple compressed bill. But it is unnecessary to compare 

 the two and point out the differences. A glance at the dimensions will alone 

 suffice to show specific distinction. There is no other bird in the family that 

 .S. Cassini in the least resembles. 



SiMORHTNCHCS MiCROCEROS, [Brandt,) Coues. 

 ? Alca pvffmiea, Gmelin, S. N. i, pt. ii, 1788, p. 555, No. 12 ; and of the older 



authors. 13ased on the Pigmy Auk of Pennant. Not identifiable. 

 Siviorhynchus pygmoRus^ Schlegel, Urinatores Mus. Pays-Bas, 1867, livr. ix, p. 

 23. Identifies A- pygmaa Gm. as Phaleris microceros Brandt or P. nodirostra 

 Bonap., and Lfria pusilla Pall, as young of the same. 

 Phaleris microceros, Brandt, Bull. Acad. St. Petersb. ii, 1837, p. 346. 

 Phaleris {Ciceronia) microceros, Cassin, B. N. A. 1858, p. 908. 

 Ciceronia microceros, Reichenbach. 



Phaleris nodirostra, Bonaparte, Comp. and Geog. List, 1838, p. 66. Equals 

 microceros Brandt. Audubon, Orn. Biog. v, 1839, p. 101, pi. 402. Audu- 

 bon, B. Amer. vii, 1844, pi. 468. Gray, Genera Birds, iii, 1849, p. 644. 

 Ciceronia nodirostris, Bonaparte, Consp. Gav. Comptes Rend., 1856, xlii. p. 774. 

 "?Phaleris corniculata, Eschscholtz," (Gray.) Doubtful citation. Perhaps 

 Fratercula corniculata ? or Cerorhina monocerata ? 



Asiatic and American coasts of North Pacific; Kamtschatka ; Kurile 

 Islands ; Plover Bay ; Sitka ; Japan. Numerous specimens in the Mus. Acad., 

 Philadelphia, and Mus. Smiths. Inst., from various localiiies. Not known to 

 occur as far south as Washington Territory, U. S., though found in the 

 Japan Sea. 



Smallest of the Auks with the ex- 

 ception of S. pusillus. Bill very short, 

 not half as long as the head, stout, 

 deep, wide, little compressed, obtuse 

 at the tip ; its width at base nearly 

 equalling its heighth at the same 

 point, and but little less than the 

 length of culmen. A small but con- 

 spicuous globular tubercle arising 

 from base of culmen, beyond which 

 the culmen is strongly arched, very 

 regularly convex, rapidly descending, 

 its tip not very acute, obsoletely 

 notched on the tomia, very slightly 

 overhanging the tip of under mandi- 

 Fig. n.-Sr«.orAyncft«s mrcrocem, (Brandt), ble. Commissure almost straight its 

 Nat. size. whole length, the extremity very 



slightlv ascending. Gonys short, rapidly ascending, very slightly convex. 

 Nosinls in a short but wide and deep fossa, placed rather higher up above 

 the commissure than in some species ; narrowly linear, not reached by the 

 frontal feathers. Frontal feathers extending to the node on the culmen, 

 then retreating obliquely backwards as they descend along the sides of the 

 upper mandible ; feathers on side of lower mandible extending farther than on 

 upper mandible. Proportions of wings, tail, legs and feet as m other species 



of the genus. , , . , , ,. . , • i- „ 



Adidl.—l'ovch^&A and lores conspicuously marked with delicate hair lines 

 of white, produced by numerous short, stiff, but very slender white setaceous 

 feathers scattered thickly thereover ; a few of which filaments, more elon- 

 gated and thread-like than the frontal ones, stretch adown the sides of the head 



