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BIRDS OF THE REPUBLIC OF PANAMA PART 4 



tanagers. Ordinarily, only 1 Wilson's Warbler was in each band, but 

 occasionally there were 2 or 3. They were noisy, constantly giving a 

 chip-chip-chip-chip or tsip-tsip-tsip. 



WILSONIA PUSILLA PILEOLATA (Pallas) 



Motacilla pileolata Pallas, 1811, Zoogr. Rosso-Asiat., 1, p. 497. (Kodiak Island, 

 Alaska.) 



Characters. — Forehead light cadmium; upper surface paler green. 



Measurements— Males (10 from Chiriqui), wing 55.0-61.0 (57.1), 

 tail 47.8-52.0 (50.0), culmen from base 9.7-11.3 (10.7), tarsus 172- 

 19.9 (18.3) mm. 



Females (10 from Chiriqui), wing 55.0-59.4 (56.0), tail 45.8-48.6 

 (47.5), culmen from base 9.2-11.4 ( 10.2) , tarsus 16.8-18.8 (18.0) mm. 



Winter visitor from the north, breeding in the Rockies and most of 

 western Canada and northwestern United States. Abundant in the 

 highlands of western Chiriqui, less numerous farther east. Monniche 

 (Blake, Fieldiana: Zool., vol. 36, no. 5, 1958, p. 560) collected this race 

 on the Volcan de Chiriqui between 1560 and 2700 m. W. W. Brown, 

 Jr., found it at Boquete as low as 1200 m (Bangs, Proc. New England 

 Zool. Club, vol. 3, 1902, p. 61) ; I have seen the species there from 1260 

 to 2610 m. Monniche collected specimens of this race from September 

 17 to May 16. Griscom (Bull. Mus. Comp. Zool. 78, 1935, p. 369) 

 considered this race fairly common in Veraguas and listed it from the 

 Canal Zone. 



WILSONIA PUSILLA CHRYSEOLA Ridgway 



Wilsonia pusilla chryseola Ridgway, 1902, Bull. U.S. Nat. Mus., 50, pt. 2, pp. 705, 

 714. (Red Bluff, California.) 



Characters. — Upper surface suffused with yellow, lighter than any 

 other race. 



Measurements. — Males (10 from North America, taken in April and 

 May), wing 52.0-58.5 (55.0), tail 44.1-49.9 (48.2), culmen from base 

 9.6-11.9 (10.5), tarsus 15.9-19.9 (17.2) mm. 



Females (10 from North America, taken in May), wing 50.8-55.5 

 (52.8), tail 44.5-49.9 (47.1), culmen from base 9.7-11.3 (10.8), tarsus 

 17.3-19.0 (18.2) mm. 



Winter visitor from the north, breeding in the Pacific coast region of 

 the United States and Canada. Rare in the highlands of western Chiri- 

 qui. I know of only 4 specimens of this well-marked race that have 

 been taken in Panama. Arce collected a male on the southern slope of 



