Family 4. Charadriid^:. Plovers. 



Shore-birds of small or medium size, having plump, rounded bodies; shortened necks; long, pointed wings reach- 

 ing to or beyond tip of tail; and, especially, a short bill (usually shorter than head) shaped much like that of a pigeon, 

 i. e., contracted and softened basally, expanded and horny distally; hind toe very small or wanting. Coloration 

 often notably black and white. A notable family, well distributed, of about 75 species — 7 Californian. 



I. Wing over 6.50. 



A. Wing about 8.00; axillars black. 254. Black-bellied Plover. 



B. Wing about 6.85; axillars brownish gray. 255. American Golden Plover. 



II. Wing less than 6.50. 



A. Chest crossed by two black bands. 256. Killdeer. 



B. Chest crossed by a single black band. 



1. Feet partially webbed; bill about .50. 257. Semipalmated Plover. 



2. Feet not webbed; bill about .85. 259. Belding's Plover. 



C. Black confined to sides of chest. 258. Snowy Plover. 



D. No black on chest at any season. 260. Mountain Plover. 



Family 5. Aphrizid^e. Surf-birds. 



Medium-sized Shore-birds having well-developed hallux; bill somewhat pigeon-like, but the upper mandible 

 grooved; the nostril a lengthened slit; scutellation of acrotarsium reduced, the remainder of the tarsal envelope 

 reticulate. A monotypic group ranging along the western coast of the Americas. 



261. Surf-bird. 



Family 6. Arenariid^:. Turnstones. 



Medium-sized Shore-birds having well-developed but small hallux; tarsus with regular scutells both in front 

 and behind; bill compressed, short, sharpened; nostrils slit-like; tail slightly rounded. A wide-ranging, northern 

 family of two species, both Californian. 



I. Chin and throat always white; plumage variegated. 262. Turnstone. 



II. Foreparts, including chin and throat, blackish. 263. Black Turnstone. 



Family 7. H^EMATOPODiDiE. Oyster-catchers. 



Large-sized, sturdy, rock-haunting Shore-birds, having all black, or black-and-white plumage, stout feet and 

 legs, with only 3 toes, and large, exceedingly compressed chisel-shaped beaks adapted to prying. A single genus of a 

 dozen species and subspecies, haunting the tropic and temperate shores of the world. 



I. Plumage all black. 265. Black Oyster-catcher. 



II. Plumage black and white. 264. Frazar's Oyster-catcher. 



Order ii. LARIFORMES. 

 Family 1. Stercorariid^e. Skuas and Jaegers. 



Long-winged and chiefly long-tailed Lari, having extensive cere on maxilla, strongly hooked beak; and claws 

 relatively large, sharp, and strongly curved. A highly specialized, predatory group, enjoying peculiar immunity 

 by reason of close resemblance to milder forms. Chiefly sub-Arctic and sub-Antarctic in distribution, but roving 

 with quarry. Seven species, of which 4 Californian. 



I. Largest and stoutest; wing over 15.00 inches. 



II. Smaller and lighter; wing under 15.00. 



A. Middle pair of rectrices broad throughout, their distal portion 



twisted and tips rounded. 



B. Middle rectrices tapering, sharp-pointed, not twisted. 



1. Central pair of rectrices projecting about 4 inches beyond 



others. 



2. Central rectrices projecting about 8 inches. 



266. South American Skua. 



267. Pomarine Jaeger. 



268. Parasitic Jaeger. 



269. Long-tailed Jaeger. 



Family 2. Larid^e. Gulls. 



Somewhat stoutly proportioned Lari, having moderate wing development; tail usually square; stronger feet, 

 compressed tarsi; bill relatively stout, moderately and broadly, or just perceptibly, hooked, the gonydeal angle empha- 

 sized. A well-distributed group of some 60 species, of which 13 are reported as Californian, although not more than 

 3 as breeders. 



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