NATURAL SCIENCES OF PHILADELPHIA. Gl 



With the general habitus of Uria proper, but of much more delicate build, 

 different ])attern of coloration, and very small size. Bill small, slender, much 

 shorter than the head, not longer than the tarsus, greatly compressed, acutely 

 tipped ; culmen gently curved, its ridge sharj), rictus nearly straight, gonys 

 straight ; tomial edge of upper mandible greatly inflected towards the base, 

 notched near the tip. Is'asal lossffi small and shallow, nearly filled with 

 feathers, which mostly cover the extremely minute oval nostrils. Wings of 

 ordinary length, very narrow, pointed, falcate, the secondaries extremely short. 

 Tail of ordinary length, almost square, the feathers obtusely rounded. Feet 

 very small, short, slender, and weak ; tarsus scarcely compressed, variable in 

 length, never longer than the middle toe without its claw (except in brachyp- 

 terus f) Outer and middle toes equal in length ; the claw of the former much 

 smaller than that of the latter ; the inner very short, its claw not reaching 

 the base of the middle claw. Claws small, weak, moderately curved, very 

 acute. 



The genus which comprises the Murrelets — to coin an English word, needed 

 for the Brachyrhainphi, — is a very natural and strongly marked one. It comes 

 nearest to Una proper, from which, however, it is sufficiently distinguished, as 

 will be seen by the above diagnosis. It contains four or five species, all inhab- 

 itants of the North Pacific, and more particularly of the west coast of North 

 America. These may readily be diagnosticated as follows : — 



Species : — (5.) 



I. Tarsus much shorter than the middle toe without its claw. 



Upper parts blackish and chestnut, lower parts blackish 



and white 1. marmoratus. 



Upper parts cinereous and white, lower parts pure 



white 2. Wrangelii. 



II. Tarsus just as long as the middle toe without its claw. 



Under surface of wings white 3. hypoleucus. 



Under surface of wings dusky 4. Craveri. 



III. Tarsus longer than the middle toe without its claw, (teste 



Brandt) b.brachypterus f 



Bkachyrhamphus marmoratus, (Gni.) Brandt. 



Coli/mhus marmoratus^ Graelin, Syst. Nat. i, 1758, p. 583, No. 12, Based on the 



marbled guillemot, Pennant,* Arct. Zool. ii, p. 517, pi. 22, and Latham, Syn. 



vi, p. 33ti, pi. 96. Donndorff, Beytr. Zool. ii, pt. i, 1794, p. 870. 

 Uria marmorata, Latham, Ind. Orn. ii, 1790, p. 799. Stephens, Shaw's Gen. 



Zool. xii, 1824, p. 249. Bonaparte, Synopsis, 1828, p. 423. 

 Bruchyrhamphus [Apobapton) marmoratus, Brandt, Bull. Acad. St. Petersburg, 



ii, 1837, p. 346. Cassin, Birds N. A. 1858, p. 915; in part. Description 



of supposed adult is that of B. Wrangeli. 

 Brachyrhamphus marmoratus, Gray, Genera Birds, iii, 1849, p. 614. Cooper and 



Suckley, Nat Hist. Wash. Terr. 1860, p. 286, in part. Not the description 



of supposed adult, which is that of B. Wranyeli. 

 Anobapton ( Brachyrhamphus) marmoratus, Bonaparte, Tabl. Comp. Pelagiens, 



Comptes Rendns, 1856, xlii, p. 774. 

 Cepph :s pcrdix, Pallas, Zoog. R.-A. ii, 1811, p. 351, pi. 80. 

 Uria Towmendii, Audubon, Orn. Biogr. v, 1839, p. 251, pi. 430; octavo ed. vii, 



1844, pi: 475. The figure of the supposed young is the adult ; that of sup- 

 posed adult may be really B. Wranyelii. 



* "With a black bill ; crown dusky; throat, breast, and belly mottled with black and 

 white ; iMck and sides very glossy, and marbled with Black and rust-color; wings dusky ; 

 greater coverts edged With wliile; tail black ; legs yellow; webs black. Length 1) inches." ■ 

 Pennant, 1. c. From Prince William Sound. Of this species, VielUot, tNouv. Diet, xiv, 

 1817, p. 36,) not exhibiting great sagacity, remarks, that it is " une jeuue guillemot grylle, 

 qui commence k prendre lu livree de I'adultel" 



1868.] 



