78 



the case. In fact a very young bird, not yet full-grown, no. 117, 

 670 in the Museum of Comparative Zoology, has no cinnamon- 

 rufous patch whatever, and since Bourcier does not mention such 

 a patch at all, we suspect that he had a young bird. Also in the 

 series of fifteen specimens from Costa Rica, examined by us, there 

 is none, young or adult, with any green or bronze on the chest such 

 as Bourcier described by the words "gris-noir bronze," whereas in 

 the southern form the dark-gray chest is strongly mixed with green. 



The Darien bird, Threnetes ruckeri darienensis Bangs and Bar- 

 bour, has much paler gray under parts than true ruckeri, and the 

 middle portions of the tail-feathers are not purplish. The upper 

 parts, however, are dark green as in the bird from Esmeraldas, — 

 in other words, it is an intermediate form. A bird from the Carib- 

 bean coast of Panama in the Museum of Comparative Zoology at 

 Cambridge and, according to Chapman (Bull. Amer. Mus. Nat. 

 Hist., vol. 36, 1917, p. 279), birds from the Canal Zone, are also 

 intermediate but much nearer the Costa Rican than the Darien 

 form. 



We have used the generic term Threnetes instead of Hetero- 

 glaucis, because the characters of the latter appear to be of sub- 

 generic rather than of generic value. The four subspecies of 

 Rucker's Hermit are thus: 



1. Threnetes ruckeri ruckeri (Bourcier), Proc. Zool. Soc. London, 

 1847, p. 46. (No type locality stated — we select Esmeraldas, 

 northwestern Ecuador.) 



Range : western Ecuador and western Colombia. 



2. Threnetes ruckeri darienensis Bangs and Barbour, Bull. Mus. 

 Comp. Zool., vol. 65, no. 6, 1922, p. 204 (Mt. Sapo, eastern 

 Panama). 



Range : eastern Panama to State of Santander and Santa Marta, 

 Colombia. 



3. Threnetes ruckeri venezuelensis Cory, Field Mus. Publ., no. 

 167, ornith ser., vol. 1, no. 7, 1913, p. 286 (Orope Zulia, Venezuela). 

 Not seen by us. 



Range: western Venezuela. 



4. Threnetes ruckeri ventosus Bangs and Penard. (Type locality: 

 Pozo Azul, western Costa Rica.) 



Range: Costa Rica, north to Nicaragua (to Guatemala?); south 

 to Canal Zone of Panama where not typical, approaching T. r. 

 darienensis. 



