THE HUMMING BIRDS. 333 



found it to be a " common summer resident in the Catalina Mountains, 

 where it breeds very commonly. Arrives early in March, and is abun- 

 dant by the last of that month. By the last of April the birds are 

 mated and begin breeding; and I have found nests with fresh eggs 

 late in July and early in August. By the 10th of October they have 

 all left the region in question." He found it to be of uncommon occur- 

 rence above an altitude of 7,000 feet, but it was common and breeding 

 at Fort Lowell, " which is north of Tucson and lies at about the same 

 altitude," though about the latter place Mr. Herbert Brown regards it 

 as rare, and has not found it breeding. 



The black-chinned Humming Bird has not yet been found as far to 

 the eastward in the Rocky Mountain district as Selasphorus platycercus 

 and S. rufus, the Uintah Mountains, Utah, being the easternmost limit 

 recorded. In these mountains the present writer found it rather com- 

 mon in July, 1869, while it was also fairly common in the Wahsatch 

 Mountains and in the vicinity of Salt Lake City. 



It habits are essentially the same as those of the Ruby-throat. 



Gernis CALYPTE Gouid. 



Calypte Gould, Iutrod. Troch. Oct. ed. 1861, 87. Type, Oniismya costw Bourc. 

 Leucaria Mulsant, Cat. des Ois. Mouch. 1875, 29. Type, Omismya costw Bourc. 



Generic Characters. — Adult males with the top of the head bril- 

 liantly metallic (red, purple, or violet), like the gorget, with its elon- 

 gated lateral ruff-like extensions, and the tail emarginated or slightly 

 forked, with the outer pair of feathers abruptly narrower than the 

 rest (except in C. helenw), and destitute of white or rufous markings; 

 adult females with outer tail-feathers decidedly narrower than the 

 next, but with broad rounded end, and without any rufous. 



In this genus, or subgenus, the primaries are nearly intermediate in 

 form between those of Trochilus and those of Selasphorus, though much 

 more like the former. The males are very easily distinguished by the 

 characters given above from those of both the other genera mentioned ; 

 but the females are so much like those of the species of Trochilus in 

 both form and coloration that size alone is the easiest way to distin- 

 guish them — that of C. costce being smaller, while that of C. anna is 

 larger than the female of either species of Trochilus. From the females 

 of any species of Selasphorus, as well as from that of Atthis, those of 

 Calypte may be distinguished by the entire absence of any rufous on 

 the tail. 



Of the known species, two belong to California and northwestern Mex- 

 ico and one to Cuba, the latter being aberrant in some parts of its 

 structure as well as coloration, and perhaps entitled to subgeneric if 

 not generic separation. It is the smallest of all Humming Birds, being 

 considerably less than the Vervain Humming Bird of Jamaica and Hayti 

 {Mellisuga minima), which hitherto has enjoyed the distinction of being 

 least among birds. 



