16 HUMMING-BIRDS. 



[Case 31.] 

 CALYPTE. " Aztecs." 



These beautiful little birds have very pointed tail-feathers, and the 

 colour of the throat is extremely brilliant in the males. The feathers 

 of this luminous throat are also elongated at the sides, forming a kind 

 of shield. Three species exist — C. costce and 0. amice from Mexico and 

 California, and 0. helence from Cuba. 



[Case 31.] 

 SELASPHORUS. " Elame-bearers." 



Also in these Humming-birds the outer tail-feathers are pointed, 

 but the whole tail is very much broader. The throat-feathers are 

 elongated at the side, and form a shield of brilliant colouring as in 

 Galypti. The sound produced by the wings of these birds when in 

 motion has been described as a loud rattling noise, more like the 

 shrill chirrup of a locust than the buzzing of wings. They may often 

 be seen during the early summer to mount forty or fifty yards straight 

 up in the air, poising themselves a moment or two, and then darting 

 down again, repeating the same manoeuvre several times in succession. 

 Sometimes, says Mr. Trippe, a score or more may be seen darting up 

 and down together in this way for half an hour or more. 



Eight species are known, and these range from Yeragua in Central 

 America to Mexico, and thence along western North America to Nootka 

 Sound. 



[Case 32.] 

 STELLULA. " Mexican Satellite." 



Remarkable for its long sickle-shaped wing, which has the first 

 primary stiffened. It has the throat luminous, with the lateral feathers 

 pointed and forming a shield. One species only known, Stelhda cal- 

 liope, from Mexico. 



[Case 32.] 

 ATTHIS and RHODOPIS. " Lucifers." 



The genus Atihis contains two species, A. heloisce, from Mexico, and 

 A. ellioti, from Guatemala. Only two representatives of the genus 

 Rhodopis are known — R. vesper, from Peru (here exhibited), and 

 R. atacamensis, from Chili. 



[Case 33.] 

 HELIACTIN. " Sun-gem." 



One of the most elegant of all the Humming-birds ; distinguished 

 by its brilliant metallic double crest, and Magpie-like long graduated 

 tail. The single species known, H. cornuta, comes from Brazil. 



