58 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



Genus APHRIZA Audubon. 



Aphrizaa Audubon, Orn. Biog., v, 1839, 249; Synopsis Birds N. Am., 1839, 225. 

 (Type, A. townsendii Auduhon= Tringa virgata Gmelin.) 



Medium sized (wiiig 164-183 mm.), stoutly built Charadrii with 

 plover-like bill, well-developed hallux, partly scutellate acrotarsium 

 reticulate planta tarsi, and emarginate tail. 



Bill shorter than head, plover-like (distmctly constricted subter- 

 minally aiid convex terminally in lateral profile), the maxiUa with a 

 broad cmieate groove extending from base to slightly beyond base of 

 arched terminal portion, its basal half, more or less, occupied by the 

 membraneous nasal fossa, in the lower edge of which is situated the 

 subbasal, longitudmally linear nostril; cuhnen about half as long as 

 middle toe, without claw; depth of bill at base equal to a little more 

 than one-third the length of culmen. Wing long and pointed, the 

 longest primary (outermost) extendmg beyond tips of longest ter- 

 tials. Tail more than one-third as long as wing, trimcate when spread, 

 sUghtly but distmctly emarginate when closed. Tarsus decidedly 

 longer than exposed culmen, the acrotarsium with a single row of 

 rather broad transverse scutella, but those on upper and extreme 

 lower portions broken into rather large hexagonal scales, the tarsus 

 otherwise covered with rather small hexagonal or irregular scales; 

 middle toe decidedly shorter than tarsus, the outer toe decidedly 

 shorter, the inner stiU shorter; hallux well developed though small 

 and slender, about as long as middle phalanx of middle toe; claws 

 smaU, strongly curved; anterior toes fringed with a distmct lateral 

 serrated membrane, the interdigital spaces cleft to the base. 



Coloration. — Upper tail coverts, basal half and tip of tail, broad 

 band across tips of greater wmg-coverts, and most of miderparts of 

 body white; summer adults with head, neck, back, and scapulars 

 streaked and spotted with dusky and whitish, the scapulars with a 

 few irregular markings of cinnamon -inif ous ; v/inter adults with head, 

 neck, chest, and most of upper parts plam dusky grayish bro-wii; 

 young like winter plumage but general color lighter brownish gray, 

 the feathers margined with whitish. 



Range. — -Pacific coast of America, from Alaska to Chile. (^lono- 



typic.) 



APHRIZA VIRGATA (Gmelin). 



SURF BIRD. 



Adults in breeding lilumage (sexes ahke). — Head and neck, all roimd, 

 streaked with blackish and grajash white, the blackish streaks broad- 

 est on pileum, narrov»'est on throat, which, together with chin, is some- 

 times immaculate wliite or only sparsely flecked with dusky, the 

 whitish streaks on pileum sometimes tinged or suffused with grayish 

 buff; scapulars and interscapulars black centrally, more or less 



a From 'A0pos, foam; taw, to live. (Audubon.) 



