INTRODUCTION. 



cm 



Hemithylaca Edwardi, Cab. et Hein. Mus. Hein. Theil iii. p. 37, note. 

 Habitat. Panama, Costa Rica, and Veragua. 



I have specimens of this bird killed by Mr. Bridges near David, at an elevation of from 8000 to 10,000 feet, 

 according to the label attached. 



355. Erythronota NivEivENTRis, Gould .......,,, Vol. V. PL 319 



Chlorestes niveiventris, Reichenb. Troch. Enum. p. 4, pi. 700. figs. 4566-67. 



Hemithylaca niveiventris, Cab. et Hein Mus. Hein. Theil iii. p. 37. 

 Habitat. Panama and Veragua. 



356, Erythronota elegans, Gould ........... Vol. V. PI. 320. 



Habitat. Unknown. 



This is a very elegant species, and quite distinct from every other known Humming- Bird. In its glittering 

 light-green crown, throat, and chest it looks like a CUorostilbon ; but the form of its tail and some other characters 

 ally it to the Erythronotce^ with which I have provisionally placed it. 



The next natural section is that of Saucerottia, of which I am acquainted with three species distinguished from 

 the ErythronotcB by their larger size, stouter bills, and by their more uniform dark-green colouring. All are 

 confined to a comparatively limited area — namely, Costa Rica, Veragua, Panama, and the northern parts of New 

 Granada. 



Genus Saucerottia, Bonap. 



357. Saucerottia typica, Bonap. 



Erythronota Saucerottei Vol. V. PL 321. 



Habitat. New Granada. 



358. Saucerottia Sophia. 



Erythronota Sophise Vol. V. PL 322. 



Habitat. Costa Rica, Veragua, and New Granada. 



359. Saucerottia Warszewiczi. 



Hemithylaca Warszewiczi, Cab. et Hein. Mus. Hein. Theil iii. p. 38. 



Habitat. Banks of the River Magdalena. 



As the ^S. SophicB differs from the S. typica in the richer blue colouring of its upper and under tail- coverts and 

 tail, so does this species differ from the S. Sophia in having the tail and its coverts both above and beneath of a 

 still richer and more violet blue. It is also of smaller size ; and the green of its under surface is different from 

 that of both, being purer and deeper. The examples in my collection were obtained by M. Warszewicz on the 

 banks of the Magdalena. 



The bird to which M. Bourcier has given the specific name of cyanifrons requii-es separation from the last three 

 species, as much or more than they do from their predecessors the Erythronotfs. M. Cabanis's generic name of 

 Hemithylaca having been apphed to this group as a whole, subsequently to those of Saucerottia and Erythronota, I 

 must either place his name in the rank of a synonym or adopt it for the present species, the only one of this 

 particular form. 



Genus Hemithylaca, Cab, 



360. Hemithylaca cyanifrons. 



Saucerottia cyanifrons ............. Vol. V. PL 323. 



Hemithylaca cyanifrons. Cab. et Hein. Mus. Hein. Theil iii. p. 39. 

 Habitat. New Granada. 



Somewhat allied to the genera Hemithylaca and Erythronota is the isolated form constituting ray genus 

 Eupherusa. The single species known is a native of Central America. Contrary to what occurs among the 

 ErythronotcB, the sexes differ very considerably in their plumage— a fact of which I was not aware when my plate 

 of the species was executed. 



