PODICIPIDA. — CXXIV. 215 
Famity CXXIV. PODICIPIDAN. (Tue Greses.) 
Bill slender, or stout; lores naked ; head often with crests, ruffs 
or ear tufts in the breeding season. Under plumage dense, lustrous, 
mostly white. Wings very short; tail rudimentary, without dis- 
tinct quills. eet four-toed, lobate, the toes webbed at base; toes 
flattened, provided with flat claws resembling human nails; tarsus 
scutellate, compressed. Genera 2; species about 20; in all parts 
of the world, chiefly about fresh waters; nest usually a floating 
mat of rushes. 
a. Bill slender, straight, rather acute; its length more than twice its depth 
at base ; head in breeding season with conspicuous crests or ruff. 
b. Neck nearly as long as body. . . . « . « . A®CHMOPHORUs, 318. 
6b. Neck much shorter than body. . . . . - « » CoLymBus, 319. 
aa. Billstout, somewhat hooked; its length not te twice its greatest depth; 
HO Tull nor crest. ss) e 6 ts ee ss ® o 6, PODILYMBUS, 320. 
318. ZACHMOPHORUS Coues. (aixun, spear; Pdpos, bearing.) 
626. 4a. occidentalis (Lawrence). WESTERN GREBE. Slate- 
color ; satin-white below. L. 26. W.8. B. 23. Minn. to Mexico 
and W. 
319. COLYMBUS Linnzus. (kddvpfos, diver.) 
a. Bill about as longas head. (Colymbus.) 
627. C. holbolli (Reinhardt). RrEp-NEcKED GreBe. Upper 
parts brown; front and sides of neck brownish red; head ashy 
gray, its top blackish; crests and ruffs not large; below silvery, 
the feathers gray within. L.18. W. 8 B. 2. N. Am. U.S. 
in winter. (To the Danish naturalist, C. Holboll.) 
aa. Bill much shorter than head. (Dytes Kaup.) 
628. C.auritus L. HornepGrese. Dark brown; head glossy 
black in @; a buffy patch above and behind eye; fore-neck, 
breast and sides brownish red ; bill compressed, deeper than wide 
at base, black, tipped with yellow; ruffs very large, in dense tufts. 
L.14. W.6. B. 3%. N.U.S.and N. (£u.) (Lat., having 
large ears.) 
629. C. nigricollis (Brehm). EArEpD Grebe. Crest of ¢ in 
the form of a fan-shaped patch; head, throat and breast black in 
d; bill depressed, wider than deep at base. L. 13. W. 51. 
Northern regions, the American var. californicus Heermann (W. 
U.S., E. to Ill.), with inner webs of inner quills dusky. (£u.) 
(Lat., niger, black ; collum, neck.) 
320. PODILYMBUS Lesson. (Podiceps-Colymbus.) 
630. P. podiceps (L.). DiepApperR. Dan-cuick. HELL-DIVER. 
Water WitcH. PIED-BILLED GREBE. Chiefly brownish gray ; 
silvery ash below, spotted with dusky ; chin and throat black; bill 
