38 
allen’s naturalist’s library. 
groups of Cypselidm, as, in a work on “British Birds,” only the 
True Swifts concern us directly, the Spine-tailed Swifts very 
little, and the Tree Swifts, which are exclusively tropical, not 
at all. 
THE TRUE SWIFTS. SUB-FAMILY CYPSELINHi:. 
The characters of this Sub-family, as detailed above, are 
the feathered toes, and the presence of only three phalanges 
in the outer and middle toes. 
THE TYPICAL SWIFTS. GENUS MICROPUS. 
Micropus, Meyer undWolf, Taschenb. i. p. 280 (1810). 
Type, M. apus (L.). 
In this genus the toes are very strong, without feathers, and 
all four are directed forwards, the same interval dividing each 
toe from its neighbour. 
The typical Swifts arc principally birds of the Old World. 
Two species only occur in South America, in the Andes of 
Ecuador, Peru, and Bolivia, and these species appear to 
descend to lower levels in winter and to visit Argentina, but 
over the whole of Brazil and Amazonia the genus is unrepre- 
sented, while in North America its place is taken by the Pied 
Swift {Aeronantes). In Europe and Asia the_ Swifts are 
summer visitors, not breeding far north, and leaving for their 
winter quarters very early in the autumn. _ A considerable 
number of resident species are found in Africa, which is also 
the winter home of our two British species. 
I. THE WHITE-BELLIED SWIFT. MICROPUS MELBA. 
Linn. S. N. i. p. 345 (176s)- , 
Cypselus inelba, Macg. Br. B. iii. p. 61 1 (1840) j Dresser, B. 
Eur. iv. p. 603, pi. 269 (1874) ; Newton’s ed. Yarn ii. p. 
372 (1874); B. O. U. List, p. 74 (1883); Seebohm, Br. 
B. ii. p. 297 {1884); Saunders, Man. p. 253 (18S9). 
Aficropus melba, Hartert, Cat. B. xvi. p. 438 (1892). 
Adult Male. — Distinguished by its large size and white abdo- 
men. General colour above mouse-brown, darker on the 
