40 
Mr. D. G. Elliot on the Trocliilidse. 
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. 
Hab. Trinidad, Cayenne, Guiana, Venezuela [Goering). 
Lesson undoubtedly had this species before him when he 
described his Ornismya albirostris {L <?.); but why he stated the 
mandible to hewhite it is difflcult 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 states that it fflest pas rare dans les collec- 
