40 Mr. D. G. Elliot on the Trochilidse. 



its whole extent, passing from the head -waters of the affluents 

 of this mighty river into the vicinity of Bogota. T. ni- 

 tidifrons has been given as a native of Venezuela ; but the 

 locality from which the few known specimens came has not 

 been ascertained, and it can be deemed only a conjecture 

 that this country is its habitat. Trinidad, besides the species 

 named, also contains the bird I have called in this paper T. 

 nigricauda, which apparently ranges along the coast to Bahia ; 

 but its precise continental dispersion I do not know. From 

 British Guiana Mr. Gould obtained the bird named by him 

 T. maculicauda ; and from some part of the same country was 

 received T. compsa ; but the precise range of both is un- 

 known. From Cayenne comes the bird I have named pro- 

 visionally T. nitidicauda ; but how far it is distributed, or in 

 what precise direction, I am unable to say. Brazil, the last 

 country that claims our attention for the birds of this genus, 

 is the habitat, besides those already mentioned, of T. tephro- 

 cephalus, which inhabits the delta of the Amazons ; and, lastly, 

 T. brevirostris is found in the province of Minas Geraes and 

 the vicinity of Rio Janeiro. 



In reviewing the various species, I have followed the ar- 

 rangement given in the analytical table; and commencing 

 with the group having a white throat and breast, the first 

 species that presents itself is 



1. Thaumatias chionopectus, 



Ornismya albirostris, Lesson, Hist. Nat. Ois.-Mouch. p. 212, 

 pi. 78. 



Thaumatias chionopectus, Gould, Mon. Troch. v. pi. 293; id, 

 Intr. Mon. Troch. 8vo ed. p. 152. 



Hah. Trinidad, Cayenne, Guiana, Venezuela [Goering). 



Lesson undoubtedly had this species before him when he 

 described his Ornismya albirostris (/. c); but why he stated the 

 mandible to hewhite it is difficult to explain. The supposition of 

 Mr. Gould that Lesson described from a made-up specimen, 

 with the head and body of Thaumatias leucogaster and the tail 

 of T. chionopectus, might be correct, if the species were rare ; 

 but as Lesson state? that it " n'est pas rare dans les collec- 



