4l6 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I50 



lower i^eck, breast and sides with slightly elongated spots of dark 

 neutral gray. 



Iris dark brown; bill black; tarsi and feet dull black to blackish 

 olive. 



Measurements (From Ridgway, I.e. pp. 232-233). — Males, wing 

 152-174 (162.7), tail 60-66 (62.2), exposed culmen 31-36.5 (33.9), 

 tarsus 29.5-33.0 (31) mm. 



Females, wing 155-176 (166.3), tail 57-65.5 (62.3), exposed culmen 

 32-38 (36.3), tarsus 29.5-33 (31.5) mm. 



Migrant from the north ; casual in occurrence. 



The knot is another of the sandpipers that nest in the tundras of 

 the far north. In winter and in migration it is found from the eastern 

 and southern coasts of the United States south to the southern tip of 

 South America. 



The only records for Panama are two immature males in winter 

 plumage, taken by Wedel, at Puerto Obaldia, San Bias, September 12 

 and 22, 1934, preserved now in the U. S. National Museum. 



CROCETHIA ALBA (Pallas): Sanderling; Playerito Arenaro 



Trynga (alba) Pallas, in Vroeg, Cat. Rais. Ois. Adumbratiunculae, 1764, p. 7. 

 (Holland.) 



Palest in color of the small sandpipers ; pure white underneath, with 

 a broad white band in the wing that shows in flight. 



Description. — Length, 170 to 180 mm. No hind toe. Winter plum- 

 age, broad forehead and undersurface, including under wing coverts, 

 pure white ; crown and hind neck pale gray, with narrow streaks of 

 dusky ; back darker gray with shaft lines of dusky ; rump and upper 

 tail coverts white at sides, blackish in the center, bordered narrowly 

 with white ; outer tail feathers light brownish gray, central pair 

 dusky, bordered narrowly with white ; lesser wing coverts, primaries, 

 and secondaries dull black; middle and greater coverts brownish 

 black, edged and tipped with white; a broad white mark across pri- 

 maries and secondaries. 



Breeding plumage, basally black above, with the feathers edged 

 with bright cinnamon-bufT and grayish white; side of head, throat, 

 neck, and upper breast light cinnamon-buff, dotted with black. This 

 is the plumage from May to August that, in the main, disappears by 

 the end of September. The majority of migrants found in Panama 

 are in winter dress. 



Measurements (from Ridgway, I.e., pp. 308-309). — Males, wing 

 113-124.5 (119.1), tail 45-55 (50.3), exposed culmen 23-26 (24.7), 

 tarsus 23-25 (23.7) mm. 



