INTRODUCTION. Ivii 



feature so conspicuously marked as in the members of the succeeding genus Chdyhira ; there it is carried to its 

 maximum, and is rendered so much the more apparent from the striking contrast of the snow-white-plumed under 

 tail-coverts with the dark or black colouring of the tail-feathers. These birds form a very natural section of the 

 TrochiUd^. Venezuela, New Granada, and Panama may be regarded as their head quarters,— two of the species, 

 C. Buffoni and C. ccerideog aster, being frequently sent in collections from Bogota. 



Although the sexes of this genus of birds are very differently coloured, the females have the plumed under tail- 

 coverts as well as the males. 



Genus Chalybura, Rekhenh, 



102. Chalybura Buffoni. 



Hypuroptila Buffoni . . . . , . , . . . . ' , , Vol, 11. PI. 89. 



Chalybura Buffoni, Reichenb. Aufz. der Col. p. 10 ; Cab. et Hein. Mus. Hein. Theil iii. p. 20. 

 Agyrtria Buffonii, Reichenb. Troch. Enum. p. 7, pi. 766. figs. 4773-74. 

 Habitat. Venezuela and New Granada. 



103. Chalybura urochrysia, Gould. 



Hypuroptila urochi-ysia, Gould .*;........ Vol. II. PL 90. 



Habitat. Panama. 



104. Chalybura c^ruleogastra, Gould. 



Hypuroptila ceeruleogaster, Gould ........... VolII. PL 91. 



Cyanochloris coeruleiventris, Reichenb. Aufz. der Col. p. 10. 



Agyrtria coeruleiventris, Reichenb. Troch. Enum. p. 7, pi. 77. figs. 4775-76. 



Chalybura caeruleiventris, Cab. et Hein. Mus. Hein. Theil iii. p. 20. 



Habitat. Ncav Granada. 



105. Chalybura? Isaur^, Gould. 



Hypuroptila Isaurce, Gould in Proc. of Zool. Soc. part xxix. p. 198. 



Habitat. The Bocca del Toro in Costa Rica. 



Head, all the upper surface, wing- coverts, flanks, and abdomen coppery bronze, inclining to purple on the 

 lower part of the back and upper tail-coverts ; wings purplish-brown ; tail very dark bronze, inclining to purple ; 

 throat and breast grass-green ; under tail-coverts white; upper mandible black; under mandible fleshy, with a 

 black tip ; tarsi yellow or flesh-colour. 



Total length 4|- inches ; bill 1-V ; wing 2-|- ; tail If ; tarsi 4-. 



The specimen from which the above description was taken is somewhat immature ; it is, however, sufficiently 

 advanced to show that it would have, when adult, a fine green breast ; but whether the green colour would extend 

 over the abdomen, I am unable to say. It is nearly equal in size to the C. urochrysia, C. Buffoni, and C cceruleigastra ; 

 but it has a shorter wing and a more rounded tail than either of those species, and the under tail-coverts, thouo-h 

 white, are less plume-like in form. It is just possible that it may be necessary to separate this bird into a new 

 genus when we see it in its fully adult state ; but it appears at present to be most nearly allied to the members of 

 the genus in which I have provisionally placed it. I received this bird from M. Edouard Verreaux, of Paris, many 

 years ago, and I have never seen another. 



The name of Isaurce was suggested to me by my late highly valued friend the Prince Charles Lucien Bonaparte, 

 who wished thus to convey a compliment to Madame la Baronne de Lafresnaye, the niece of Montbeillard, the able 

 coadjutor of the celebrated Buffon. 



Genus Iol^ema, Gould, 



(^lov, viola, et Xatiios, gula.) 

 Generic characters. 

 Male. — Bill considerably longer than the head and slightly arched; wings long and curved; primaries rigid, of 

 moderate length, and forked ; tarsi clothed ; feet rather small ; hind toe shorter than the middle toe ; nails short and 

 curved. 



This genus was proposed for the Trochilus Schreibersii of Loddiges ; and of this form Mr. G. N. Lawrence, of 



Q 



