736 PODICEPS DOMINICUS, ST. DOMINGO GEEBE. 



PODICEPS (TACHYBAPTES) I30MIXICUS, Linn. 

 St. Oomingo Grebe. 



Colymbus dominicus, L:^-^•., Svft. Nat. i, 1766, 223 (C. fluviatilis dominicensis, Briss., vi, 

 64, pi. 5, f. 2).— Gm., Svst. Kat. i, 17S8, 593. 



Fodiceps dominicus, Lath., Ind. Orn. ii, 1790, 71^5.— Spix, Av. Brae. pi. 101.— Bd., lies. 

 B. Surs-. li, 1859, pt. ii, Birds, 28 ; B. N. Am. 1860, pi. 99, f. 1 (no text, and not 

 in ed. of 18i8).— ScL., P. Z. S. Ic57. 207.— Lawe., Ann. Lye. N. Y. vii, 1861, 334 

 (Panama).— SCL. & Salv., Exot. Orn. i, 1869, 190.— Eeinii., Vid. Med. 1870, 

 17 (Brazil). 



Fodiceps (Sijlbeocyclus) dominicus, Geay, Hand-list, iii, 1871, 94, No. 10768. 



Sylbcocxjclus dominicm (Bp. ?) COUKS, Pr. Phila. Acad. 1862, 232. 



Tachybaptes dominions, Coues. 



Sah.— Warmer parts of America. West Indies. North to tbo Eio Grande. Califor- 

 nia (Gambel). 



Adult— Form as aljove described nnder head of the subgenns. Crown and occiput 

 deep glossy steel-blue. Sides of head and neck all arouud dark ashy-gr.ay, darkest 

 behind, where tinged with bluish. Chin varied with ashy and white. Upper parts 

 brownish-black, with glcssy-greenish reflections. Primaries chocolate-brown, the 

 greater portion of the inner vanes of all, and nearly all of the inner four or five, to- 

 gether with all the secondaries, pure while. Under parts silky-white, thickly mottled 

 with dusky. Upper mandible dusky, the lower mostly yellowish. 



Dimensions.— Length, about 9.50 ; wing, 3.60 ; bill along culmen, 0.70 ; along gape, 1 ; 

 tarsus, 1.25 ; middle toe, 1.75. 



This small Grebe, the ouly North American* representative of the group, has only 

 lately been ascertained to reach our southern border. It requires comparison with no 

 other of our couutry, its small size alone being diagnostic. Without a series of speoi- 

 imens I cannot present the changes of plumage. 



Genus PODILTMBUS, Less. 



< Cohjmbus, Linn., Syst. Nat. i, 17G6, 223 (not type). 



< Fodiceps, Lath., lud. Orn. ii, 1790 (not type). 



:= Fodilymbus, Lkss., Tr. Orn. i, 1831, £95 (P. enrolinensit. Lath.). 

 = Sylhcocyclus, Bp., Saggio, 1834 (same type intended). 

 ^ Bydroka, NUTT., Man. ii, 1834, 259 (type carolinensis). 



Char. Bill shorter than head, stoutest in the family, compressed, with obtuse and 

 hooked tip ; culmen about straight to the nostrils, thence declinato-convex ; gonys 

 regularly convex without decided angle ; commissure slightly sinuate at basfl, then 

 straight, then much deflected. Upper mandible covered with soft skin to the nostrils, 

 between which are two fossa;, the anterior shallow, oblong, the other deep, triangular, 

 separated from the bare loral space by an intervening ridge. Nostrils broadly oval, 

 far anterior. No crests or ruffs, but shafts of frontal feathers prolonged into bristles. 

 Eyelids peculiarly thickened. Outer three or four pftmaries abruptly sinuate near the 

 end. Tarsus much abbreviated, comparatively stout, about three-fourths as long as 

 middle toe and claw. Middle and outer toes nearly equal. Basal semipalm.ation of 

 toes more extensive than in Fodiceps. Lobe of hind toe moderate. 



The essential characters of this genus lie in the stout hooked bill, broad anterior 

 nostrils, absence of crest or ruff, bristly forehead, great emargination of primaries, and 

 extensive semipalmation of the toes. The genus Dasypiilus of Swaiuson (Classif. B. 

 ii, 1837, 369), which has been referred here, agrees very well as to the characters as- 

 signed, hut P. poliocephalns is given as type. In any event the name is a synonym, 

 being anticipated in publication. Eydroka is based upon carolinensis, but is antedated. 

 Sylbeocyclus, Bp., was meant for this genus, but, it seems, was by a blunder given over 

 head of F. minor. 



There is apparently but a single good species of this genus, although several are 

 indicated by authors. The P. aniarct'cus of Lesson (with which P. hreriroslris, Gisay, 

 Gen. of B. iii, 1849, pi. 172, is synonyiiious), from South America, is a recognizable race 

 which may be defined as follows : 



PODILYMBUS PODICEPS var. ANTARCTICDS {Less.) Coues. 



Nos. 15663, 15664, Mus. Smiths. Inst., Chili, U. S. Astron. Exped. : Size, coloration, 

 and general appearance of P. podiceps. Bill not shorter than m this species, but stouter 



*P. minor is given l)y Nuttall as inhabiting this country, but the evidence is alto- 

 gether unsatisfactory. 



