304 THE ZOOLOGIST. 



the earliest, excepting the adult Cnckoo {Cuculus canorus) to take 

 their departure.* 



Subfam. Cypselin^. 



Distinguished by the very peculiar structure of the digits, 

 each of which consists of but a single phalanx additional to the 

 unguinal phalanx, as is the case with the hind toe only of other 

 birds. The majority of the foregoing generalizations refer more 

 especially (so far as yet known) to the present subfamily, and 

 particularly to the genus Cypsclm. The species present no 

 sexual diversitj' of plumage, which is commonly sooty-black or 

 brown, with faint-coloured glosses, often relieved with white on 

 the throat, belly, and in several forming a band above the tail. 



A. With more robust feet, the representative of the hind toe 

 rotating forw'ards, and not completely opposable to the 

 other toes. 



Genus Cypselus, Illiger (Ordinary Swifts). 



These have a square or generally a forked tail, with no ten- 

 dency to be spinous ; the toes are sliort, and the tarsi are always 

 feathered above. About eighteen species are known, some of 

 which occur in most parts of the world ; two visiting Europe in 

 summer, but none N. America ; one only has been observed in 

 Australia. 



C. melba; Hirundo melha, L. ; H. alpina, Scopoli; Il.gularis, 

 Stephens; C. alpinus, Tem. ; C. gutturalis, Vieillot. — Length 

 about 8| in. ; of middle tail-feathers 2j in., the outermost f or f 

 in. longer ; wing from bend 9 in. General colour brown, with 

 white throat and belly ; a reddish-purple gloss on the back. 



Inhabits the Nilgiris, and Central India : also Africa ; and 

 chief!}' the high mountains of S. Europe, visiting rarely the 

 British Islands. Mr. Jerdon " first observed it on the road 

 between Madura and Pallamcottah, when an innumerable flock 

 passed over camp from the range of eastern ghats, travelling 

 towards the east coast. It was almost midday in the month of 



* Very rare individTial exceptions have been known to occur, but, from 

 special causes, as a late brood of young ; yet it is stated that they will some- 

 times leave a brood of unfledged j'oung to perish, so strong is the migrative 

 impulse. 



