506 



BIRDS OF THE REPUBLIC OF PANAMA PART 4 



other races. There seems no justification for the retention of a sepa- 

 rate species, D. plumbea, for the isolated gray-breasted populations. 



The female type specimen of Diglossa baritula veraguensis is not 

 nearly so distinct as Griscom ( Amer. Mus. Novit. no. 280, p. 16) made 

 it out to be and could possibly be a missexed juvenile male, being very 

 similar in appearance to an immature male from Irazu, Costa Rica, in 

 the American Museum collections ( 102322) . As far as the male plum- 

 age is concerned, a specimen from the Talamanca Cordillera (AMNH 

 no. 811902) has the pileum as well demarcated as in veraguensis. The 

 series of 5 specimens of veraguensis is quite inadequate for determining 

 geographic differentiation in a form as variable as this and it is not rec- 

 ognized here. This population is known only from the vicinity of Chitra 

 (1500 m), Veraguas, where Rex R. Benson collected 2 adult males, 2 

 immature males, and an adult female during January and February of 

 1926. The birds were breeding at the time of Benson's visit. 



The most distinctive attribute of the genus Diglossa is the structure 

 of the bill; the mandible is upturned and the premaxilla is hooked at 

 the tip, which projects beyond the mandible. The flower-piercer in- 

 serts its sharp mandible into the corolla of tubular flowers while the 



Figure 39. — Slaty Flower-piercer, Mielero Picaflor, Diglossa baritula plumbea, 



male. 



