164 SWALLOW. 
merely observing that, by way of Asia, a connection appears to be 
established near Lake Baikal with the North American Swallow, 
fT. erythrogaster of Boddaert, better known as A. horreorum. The 
latter, although found in Greenland, does not cross the Atlantic to 
Britain, nor has our bird been observed further west than about 180 
miles beyond the Azores. In Egypt. there is a resident subspecies, 
HZ. savignit, with the under parts nearly as ruddy as the throat. 
The nest was, no doubt, originally built in caves, and even now 
these are sometimes resorted to, but at the present day it is usually 
placed about human habitations or buildings of some kind ; often it 
is in chimneys, though almost any ledge or projection will serve ; 
while exceptionally it has been found in forked boughs of trees, and 
in even more remarkable sites. Mud, with a mixture of short straws, 
and a lining of fine grasses and feathers, is the material employed, 
and the structure has generally the shape of half a saucer ; the eggs, 
laid from May 18th onwards, and usually 4-6 in number, are white, 
blotched and speckled with several shades of grey and brown: 
measurements ‘82 by 54 in. Two broods are produced in the season, 
but I have known even three hatched by the same pair of (marked) 
birds, although I believe that the last brood, still in the nest on 
October 23rd, was not reared. To the extreme south of Europe the 
Swallow returns by the end of January, and below Seville I found 
many nestlings by April 16th. With us large flocks collect together 
in autumn, prior to their departure for the south, and are then 
conspicuous on roofs, trees and telegraph-wires, especially in the 
vicinity of water. The food consists mainly of gnats and crane-flies 
in spring, with small beetles in summer. The soft, low twittering 
song can hardly be described ; the alarm-note may be syllabled as 
Seet-afeet, feet-a-Ffeetit. 
The adult male in spring has the forehead and throat dark chest- 
nut ; crown, upper parts and pectoral band deep metallic blue ; 
quills dark bluish-green ; tail-feathers bottle-green, with white patches 
on the inner webs of all except the central pair, the long outside 
streamers often two inches longer than the next ; belly and under 
wing-coverts buff; under tail-coverts pale chestnut ; bill, legs and feet 
black, and very small. Length 7°5 in.; wing 4’9 in. The female 
has the tail shorter, the forehead less chestnut, and the under parts 
whiter. The young are duller in colour ; the frontlet and throat are 
pale chestnut, and the spots on the tail are tinged withrufous. The 
moult takes place in winter, and I noticed that the birds which were 
breeding in the south of Spain in April had not then attained the 
warm buff tint on the under parts, which I observed later. 
