ALPINE SWIFT. 301 



again met with an accessible nest. Indeed this was the only instance in 

 which we obserred 0. melba breeding not in large colonies." 



The eggs of the Alpine Swift are deposited late in May, and are usually 

 two or three in number, but it is said that four or even five sometimes 

 occur. They are elongated, and the small end is almost as blunt as the 

 large end. They are pure white in colour, and vary from 1-3 to 1-3 inch 

 in length, and from -8 to -72 inch in breadth. The eggs of this bird 

 occasionally have more gloss on them than is usual with those of the 

 Common Swift j but, as a rule, they are without poHsh, Their size easily 

 prevents them being confused with those of the Common Swift. 



The young are fed assiduously by their parents. The food is collected 

 in a mass in the mouth, so that a considerable amount is obtained ere the 

 old birds convey it to their young ; and it is said they thus collect all their 

 food into a little round ball before swallowing it. The young are some- 

 times fed on the wing by their parents. Like other Swifts and Swallows, 

 the present species is much infested by parasites. The Alpine Swift only 

 breeds once in the year, and disappears from its European haunts during 

 September. It passes Gibraltar on migration from late in August to 

 early in October ; but has been sometimes met with there as late as 

 November and as early as February. 



The male Alpine Swift iu breeding-plumage has the general colour of 

 the upper parts, the flants, the under tail-coverts, and a broad band 

 across the breast hair-brown, the feathers of the upper parts having a 

 faint purplish tinge, especially on the back and tail. The throat and belly 

 are pure white ; and the lores very dark brown, almost black. Most of 

 the brown feathers have indistinct narrow pale margins. Bill black j feet 

 and claws black ; irides dark brown. The female does not differ in colour 

 from the male. Birds of the year are similar to their parents ; but the 

 feathers have more conspicuous pale margins, and the pale feathers of the 

 underparts have dark shaft-lines. Nestlings are said to be covered with 

 grey down. After the autumn moult the colour of the plumage is much 

 darker and richer, and the pale margins are more conspicuous ; and after 

 the spring moult there is more iridescent gloss on the feathers. The ex- 

 tent to which this species sometimes bleaches during the summer is most 

 remarkable. I have an example from Switzerland in which most of the 

 dark parts of the plumage are the colour of sand and extremely abraded j 

 many of the feathers of the underparts have already been changed, and 

 the wing-coverts are apparently just commencing to be so. The autumn 

 moult has usually only just begun when the birds leave us, but the spring 

 moult is completed before they again arrive in Europe. The Alpine 

 Swift is subject, like most other birds, to the same climatic variation 

 of colour which is found in the Common Swift, some examples from arid 

 localities being very pale. 



