LIST OF SPECIES. l5 



[Case 26.] 

 TOPAZA. " Kings." 



The character of the tail, in which two feathers are elongate and 

 cross each other, distinguishes the "King" Humming-hirds, which well 

 deserve their appellation, for there are scarcely any other members of 

 the family which surpass them in brilliancy of plumage. The common 

 species, T.pella, is found in Guiana and the island of Trinidad, extend- 

 ing into Brazil and up the Amazon, being replaced on the Rio Negro 

 by T. pyra. 



[Case 27.] 



^THURUS. " Long-tailed Hummistg-bieb." 



This singular bird has the last tail-feather but one produced to a 

 great length, and a remarkable black crest on the head. The female 

 is very different, neither does the j'Oung male possess the graceful 

 elongated tail-feathers of the old bird. Only one species known 

 (-^. jpolytmus), which is confined to Jamaica. 



[Case 28.] 

 THALURANIA. " Wood-Nymphs." 



The members of the present genus do not show any striking charac- 

 teristic ; they possess moderate-sized wings and tail, a bill of moderate 

 length and slightly curved, forked tail, and tarsi clothed with feathers. 

 In the males the prevailing colour is green or blue, with a metallic 

 colouring on the crown or throat. The females are duller in colour. 

 Eleven species are known, extending from Northern Brazil, through 

 Guiana and Venezuela, to Ecuador, and thence, ranging northwards, 

 through Central America as far as Costa Rica and the Tres Marias 

 Islands. 



[Case 29.] 

 MICROCH^RA. " Snow-caps." 



One of the most remarkable forms, differing entirely from other 

 Humming-birds in the style of coloration. They are of diminutive 

 size, blackish, with pure- white crowns. Two species only are known, 

 from Central America. 



[Case 30.] 

 TROCHILUS. " CoLiBRis." 



Tail-feathers not so much pointed as in the preceding genus ; winf s 

 short ; the colour of the plumage not very brilliant, except on the throat. 

 Two species are known — one of them, the TrocJiilus coluhris, in- 

 habiting North America during the summer, and migrating in winter 

 to Central America and the West- India islands. It extends very far 

 north, and is replaced in California and Mexico by an allied species, 

 T. olexandri. 



