PODICEPS CALIFOENICUS, AMERICAN EARED GREBE. 733 



I once noticed a singular fact connected with the power these birds 

 liave, iu^couimou with other Grebes, of sinking quietly into the water. 

 By the respiratory process they are able to very materially reduce or 

 enlarge their bulk, with the consequence of displacing a varying bulk 

 of water, and so of changing their specitic gravity. Once holding a, 

 wounded Grebe in my hand, I observed its whole body to swell with a 

 labored inspiration. As the air permeated the interior, a sort of ripple 

 or wave passed gradusdly along, pufting out the belly and raising the 

 plumage as it advanced. ^Yith the exi>iration, the reverse change oc- 

 curred from the opposite direction, and the bird visibly shrunk in dimen- 

 sions, the skin fitting tightly and the feathers lying close. 



PODICEPS AUKITUS var. CALIFOENICUS, (Heerm.) Coues. 



American Eared Grebe. 



a. auritus. 



Colymlus aurilus, LiNX., Syst. Nat. 1766, 222 (partim). — Nauji., Yog. Dentscbl, ix, 1838, 



768, pi. 246. 

 rudicei)S uiiritus, Lath., lud. Oru. ii, 17S0, 781. — Temm., Man. 1815, 469.— Boie, Isis, 



1822, 561.— Steph., Geu. Zool. xiii, 1825, 12.— Keys. & Blas., Wiib. Eur. 1840, 



90.— ScHL., Rev. Crit. 105; M. P.-B. ix, 40.— Macgie., Man. ii, 204.— Gkav, 



Geu. of B. iii, 633 ; autl of European authors generally. 

 Proctojnts aiirUus, Kacp, Sk. Eut. Eur. Tbierw. 1829, 49. 

 Viodytcs auritiin, Reichenbacii. 

 Podktfps et Cohjmhna nigricolUs, Sundevall. 



b. californicns. 



Podicei)8 auritus, Nutt., Man. ii, 1H34, 256 ("\\ ill probably be found iu North Amer- 

 ica").— Aud., Orn. Biog. v, 1839, 108, pi. 404 ; Syn.'l839, 358 ; B. Aui. vii, 1844, 

 322, pi. 482 (described from si)ecie8 said to be North Auiericau). — Bl'., List, 

 1838, 64.— Lawk., B. N. A. 1858, 897.— Maxim., J. f. 0. vii, 18.59, 246 (descrii.tiou). 



Podiceps califonticus, Heeii.m., Pr. Phila. Acad. 1854, 179; P. R. R. Rep. x, 1859, 76, pi. 

 8 (young).- Newi!., P. R. R. Rep. vi, 1857. 110.— Lawr., B. N. A. 1858, h96.— 

 Coop. & Suck., N. H. Wash. Ter. 1860, 282.— Hayd., Rep. 1862, 176.— Stev., 

 U. S. Geo]. Surv. T(!r. 1870, 466 (North Platte).— Elliot, B. N. A. pi. 64.— Coues, 

 Ibis, 1866, 273.— SCL., P. Z. S. 1864, 179 (city of Mexico, in full plumage).— 

 Dress, Ibis, 1866, 46 (Texas, winter).— Salv., Ibis, 1866, 200 (Guatemala^. 



Podicejps (Proctopus) californicns, CouES, Pr. Phila. Acad. 1862, 231, 404.— Coues, itiU 

 1866, 100 (Arizona). 



Podiceps auritus var. calij'o) uicvs, Coues, Key, 1872, 337.— Coues, Am. Nat. Aiii, 1874 (Da- 

 kota).— Hexsiiaw, Am. Nat. viii, 1874, 243 (breeding).— Ridgw., Ann. Lye. N. 

 Y. X, 1874, 392 (Illinois).— Sxow, Am. Nat. viii, 1874, 757 (Kansas). 



Sal). — The typical form from Europe, Asia, and Africa. Yar. calif ornicus from West- 

 ern North AnitMica, from Great Slave Lake to Guatemala. East to Texas, Dakota 

 {('ones, Am. Nat. vii, 1^73, 745), Kansas {Sumv), and Illinois {liidijuaij). Breeds 

 apparently throughout its range. 



Lieutenant Warren's Expedition.— 547G, Fort Berthold; 5477, Snake River. 

 Later Expeditions.— GOtiG:i, North Platte. 



Adult, hreedinf] plumage.— Bill shorter than head, rather stout at base, much depressed, 

 broader than liigh at the nostrils, tip acute, not decnrved, gonys straight, ascending, 

 cnlmcn a little concave basally, nearly straiuht terminally. Tarsus about eiiual to 

 niiddle toe without its claw. Bill eutiicly black. Conspicuous, long auricular tufts, 

 golden-l)ro\vii or tawny, lincly displayed ujion a black ground. Crown, chin, and neck 

 all ronud, lihu'k. All the jiriniaric's entirely chocolate-brown, with usually a wash of 

 dull reddish-brown externally. Seccuularies white, but the bases of all, and a consid- 

 erable jiart of the two outer ones, dusky ; their shafts mostly all dusky. 8i<les deep 

 purplish-brown or wine-red ; this color washed acro.ss the breast, behind the black of the 

 neck, and also across the anal region. I iiiler i)arts silky-white, the abdonii-n grayish. 



i'ouu;/ — Bill sliapfil gent-rally as iu the adult, but smaller, witli less lirm outlines, 

 BO that its distinctive shape is somewhat obscured. Little or no trace of the auiicular 

 tufts. Crown, sidts of head, and neck all around, st)oty -grayish, paler and more ashy 

 ou the foreueck. Upper parts rather lighter and duller colored than iu the adults. 



