368 EEPOET OF NATIONAL MUSEUM, 1890. 



A specimen from Guayaquil, Ecuador, however, (No. 54961, Dr. Des- 

 truge) labeled by M. Lawrence " riefferi var. jacunda" on the other hand, 

 differs decidedly from all more northern examples, including those from 

 Colombia, in the very much lighter color of the tail-coverts, tail, ami 

 abdomen, the latter being very nearly white, instead of brownish gray 

 or grayish brown. 



Like the allied Buff-bellied Humming Bird, Rieffer's Humming Bird 

 was first taken within the Uuiied States by Dr. J. C. Merrill, U. S. 

 Army, who examined a living specimen brought to him by a soldier at 

 Fort Brown, but which subsequently escaped. Fortunately, however, 

 Dr. Merrill had taken u careful description of the bird while in his pos- 

 session, so there can be no question as to the correct identification of 

 the species. 



But little has been recorded of the habits of this species, the follow- 

 ing, from Gould's monograph, being all that I have been able to find : 



Mr. Bridges found it feeding on a Malvaceous plant near the Boqueti, at an eleva- 

 tion of 4,000 feet ; Mr. Salvin met with it at Cobau in November, and also near 

 Bezbal, and remarked that it was far from common at Coban, and that all the speci- 

 mens he procured appeared to be males ; and Mr. Fraser noticed it feeding from the 

 bark of a large tree in the forest of Babahoyo in Ecuador, and states that when he 

 arrived in Esmeraldas in October it was by no means uncommon, feeding morning 

 and evening arouud the eaves of the house ; in November it was very scarce, and in 

 December not to be seen. 



Genus BASILINNA Boik. 



Baxilinna Boie, Isis, 1831, 546. Type, Trochilus leucot.s Vieill. 

 Helioposdica Gould, Mon. Troch., pt. xv, 1858. Type, Trochilus melanotis Swains., 

 = T. leucotis Vieill. 



Generic characters. — Similar to Ariiazilia, but bill broader, and 

 more denuded at the base, the frontal apex being considerably posterior 

 to the mental apex, and sexes very different in coloration. 



This genus is so closely related to Amazilia that the sexual difference 

 in coloration is the most obvious difference. Only two species are 

 known, their diagnostic characters being as follows : 



Common Characters. — Above metallic green, darker or duller on 

 top of head ; tail mainly chestnut or blackish, the middle feathers, 

 however, with more or less green; a broad and very conspicuous white 

 stripe behind eye, with a black, dusky, or brownish one immediately 

 beneath it, across ear-coverts. Adult males with forehead and chin 

 black or deep blue, the throat and upper part of chest brilliant metallic 

 green. Adult females with top of head dull brownish (sometimes tinged 

 with green), and lower parts pale cinnamon (with or without greeu spots 

 on throat) or dull grayish white with sides green. 



a 1 . Tail mainly chestnut; posterior lower parts pale cinnamon. Aduttnlale: Fore- 

 head and chin opaque black, or dull blue-black ; middle tail-feathers chestnut 

 centrally, metallic green exteriorly, the rest without dusky subterminal bar 

 or spot. Adult female: Lower parts pale cinnamon, with or without greeu 

 spots on throat; middle tail-feathers entirely green, the rest marked by a 

 more or less distinct subterminal spot of dusky. Hal). Southern portion of 

 Lower California. B. xantusi (L\wr.). Xantus'a Humming Bird. (Page 369.) 



