278 



BIRDS OF THE REPUBLIC OF PANAMA PART 4 



A Blackburnian Warbler killed in a heavy rainstorm at Almirante, 

 Bocas del Toro, on October 13, 1963, weighed 9.41 g and had an esti- 

 mated 1.37 g of fat reserves, which might have enabled the bird to fly 

 another 900 km (Rogers, Bird-Banding, 1965, pp. 115-116). 



[DENDROICA DOMINICA (Linnaeus): Yellow-throated Warbler, 

 Reinita Gargantiamarilla 



Motacilla dominica Linnaeus, 1766, Syst. Nat., ed. 12, 1, p. 334. (Hispaniola.) 



Vagrant. This species is included on the basis of 3 sight reports: a 

 well-marked male that I observed for several minutes on February 3, 

 1958, at Almirante, Bocas del Toro, where it was feeding in a flowering 

 tree with other warblers and orioles; a bird seen by C. Leahy, J. 

 Gwynne, Ridgely, and Eisenmann on February 2, 1973, at Summit 

 Gardens, Canal Zone (Ridgely, 1976, p. 296) (This bird was photo- 

 graphed, but the subspecies was not determinable) ; and a bird seen by 

 J. Baird and R. Forster on Cerro Azul, Province of Panama, on Janu- 

 ary 28, 1978 ( Ridgely, in lift. ) . The white lores and short bill character- 

 istic of D. d. albilora were observed on the last-mentioned bird. D. a. 

 albilora winters rarely south to Costa Rica.] 



DENDROICA PENSYLVANICA (Linnaeus): Chestnut-sided Warbler, 

 Reinita de Lados Castanos 



Motacilla pensylvanica Linnaeus, Syst. Nat., ed. 12, vol. 1, 1766, p. 333. (Phila- 

 delphia, Pennsylvania.) 



Small; upper surface bright yellowish green; undersurface white, 

 with, on male, chestnut stripe on side of breast and sides. 



Description. — Length 106-118 mm. Adult male, crown and back 

 olive-yellow, with some black streaking on back, becoming more ex- 

 tensive in March, when crown becomes bright yellow; rump black with 

 feathers edged olive-yellow; upper tail coverts black, edged gray; wing 

 coverts blackish, with lesser coverts tipped olive-yellow, middle and 

 greater ones tipped white, tinged yellow, forming two bars; remiges 

 blackish, edge of outer web of primaries gray, edge of outer web of 

 secondaries olive-yellow; rectrices blackish with large white patch on 

 inner web of outer two pairs; lores and side of head and neck gray un- 

 til March, when lores, superciliary, and side of face in front of eye be- 

 come black and rest of side of face becomes white; orbital ring white; 

 undersurface white, with chestnut on sides becoming more extensive by 



