268 



HIRTTNDlNIDyE. 



The Swallows resemble each other closely in structure, and the 

 only point in which they vary is the shape of the tail. As the 

 shape of the tail is, however, different in almost every species, it 

 cannot very well be utilized as a generic character. The Indian 

 Swallows may be divided into four genera by characters which are 

 of considerable value, such as the feathered or bare condition of 

 the leg, the colour of the plumage and of the tail, the mode of 

 nidification, and the colour of the eggs. 



Key to the Genera. 



a. Tarsus and toes feathered CHELIDON, p. 268. 



b. Tarsus and toes bare. 



a' . Upper plumage brown and without 

 gloss. 



a". Tail-feathers uniform COTILE, p. 271. 



b". Tail-feathers with white spots .... PTYONOPROGNE, p. 273. 

 b'. Upper plumage, or the greater portion 



of it, black and highly glossy HIRUNDO, p. 276. 



Genus CHELIDON, Forster, 1817. 



The genus Chelidon contains the Martins, which are distinguished 

 from all the other birds of this group by their feathered tarsus and 



4-^,. mu _ _n j.1 _ _ _JI_L_ ._ j 



toes. The rump in all the species is white, and forms a conspi- 

 cuous feature of the Martins when flying. The shape of the tail 

 varies in the different species, C. urbica having the tail somewhat 

 deeply forked, and C. nepalensis having it quite square. 



The Martins build nests of mud lined with feathers, and lay four 

 to six pure white eggs. 



Figs. 73, 74, 75. Foot, head, and bill of C. urbica. 

 Key to the Species. 



a. Under tail-coverts white. 



a'. The longer upper tail-coverts black. 

 a". Lower plumage pure white ; fork 

 of tail half to three-quarters inch 



deep 



b" . Lower plumage pale grey ; fork of 



tail one-quarter inch, or less, deep . . 



b' . The longer upper tail-coverts white . . 



b. Under tail-coverts black 



C. urbica, p. 269. 



C. kashmiriensis, p. 269. 



C. lay opus, p. 270. 

 C. nepalensis, p 



271. 



