Mr. D. G. Elliot on the Trochilid*. 153 



selves alone to give a specific value, tlien at once an opportu- 

 nity is aftbrded for some new Brehm to flood our publications 

 with descriptions of new species, and greatly add to whatever 

 confusion may already exist ; for the members of no genus of 

 birds afford more ample materials (in the variations above 

 mentioned) for establishing separate forms with microscopical 

 differences than do the variable individuals composing this 

 genus. 



Chlorostilbon angustipennis. 



Trochilus angustipennis, Fraser, P. Z. S. 1840, p. 18. 



Chlorostilbon angustipennis, Gould, Mon. Troch. vol. v. 

 pi. 353; id. Intr. Troch. p. 175, sp. 397. 



Trochilus chrysogaster, Bourc. Rev. Zool. 1843, p. 101. 



Chlorolampis chrysogaster, Cab. & Heine, Mus. Hein. Th. iii. 

 p. 47, sp. 104 (1860). 



Trochilus phceopygus, Tsch. Faun. Peruana, p. 247, sp. 11. 



Prasitis phceopyga, Cab. & Heine, Mus. Hein. p. 49, sp. 108 

 (1860). 



Chlorostilbon assimilis, Lawr. Ann. N. Y. Lye. Nat. Hist, 

 p. 293 (1860). 



Chlorostilbon melanorhynchus , Gould, P. Z. S. 1860, p. 308. 



Chlorostilbon smaragdina, Cab. & Heine, ]\Ius. Hein. p. 48, 

 sp. 106 (1860). 



Chlorostilbon pumilus, Gould, Ann. & Mag. Nat. Hist. 1872, 

 ix. p. 195. 



Hab. Veragua (Arce) ; Panama {McLeannan, Hughes) ; Ve- 

 nezuela; Columbia [Salmon] ; Ecuador [Fraser, Buckley). 



Perhaps no species among this difficult group has given 

 more trouble to ornithologists than the one now under review ; 

 and the causes appear to be the inability of investigators to 

 get together a sufficiently large series to enable them to see 

 how greatly individuals vary from each other, and how little 

 worthy of reliance there is in a difference of size, in either 

 bill, wings, or tail, to justify specimens occupying a dis- 

 tinct specific rank. The species was first described, from a 

 specimen from Bogota, by Fraser, in the ' Proceedings ' of the 

 Zoological Society, as above cited. A few years later Bour- 



