TROCHILUS ensipennis, 

 Blue Sickle-winged Humming Bird. 



Generic Character. — See I'l. 82. 



Specific Character. 



T. (div, ciirvirostrie) aureo-viridis, mentojuguloque cceruleo-violaceis ; 

 rectricibus paribus ; alls falcatis, i-emigiim primorum scapis dila- 

 fato-compressis. 



Curved-bill Humming Bird, golden green ; chin and fore part of 

 the throat violet-blue ; tail even ; wings falcated, greater quills 

 with the shafts dilated and compressed. 



I HAVE already offered some observations on the remark- 

 able construction in the wings of T. falcatus, figured at 

 pi. 83 ; and the bird nove before us is another unrecorded 

 species, possessing exactly the same formation. I was at 

 first inclined to believe this bird was the male of the T. 

 latipemiis, (or POiseau Moiiche a larges tui/aux of Buffon), 

 from the under plumage in that species being uniform grey, 

 a common indication of the female Humming Birds ; but 

 a further comparison of the two has proved this supposition 

 to be erroneous. They differ, not only in colour, but in 

 their bills; in that of T. latipennis, the curvature is so slight, 

 that it maybe almost called straight; whereas in this, the 

 curve is very apparent. I have little doubt future obser- 

 vations will show, that these singular quill-feathers, now 

 known to exist in three species of this family, are pecuUar 

 only to the male birds. 



This extremely rare bird is in my own collection, and is 

 not improbably unique; the figure is strictly of the natural 

 size ; the plumage, above and below, is a uniform deep 

 green, with a metallic reflection; halfway down, the throat 

 is dark violet blue; tail even, and very broad, the middle 

 feathers obscure green, the next pair raven or bluish- 

 black, and the others white, with a black base. 



The progress which has been made towards ascertaining 

 the geographic distribution of animals, leaves no doubt that 

 this bird is an inhabitant of either the Continent or Islands of 

 South America ; but of what particular country is unknown. 



PI. 107. 



