BLACK SWIFT. 621 



in the same manner, and exhibit other points of mntual re- 

 semblance ; as do the Terns more especially, which, on account 

 of their form and buoyant flight, have received the vulgar ap- 

 pellation of Sea Swallows. 



The want of walking feet might be supposed to be somewhat 

 inconvenient on many occasions. Thus, when the bird has its 

 nest to make, it must gather straws and feathers. But so 

 great is its dexterity on wing that it picks them up with ease 

 as it skims along. The nest is placed in the crevice of a wall 

 or rock, in a steeple or tower, in holes under the eaves, or in 

 some such place, at as great a height as possible, and is com- 

 posed of twigs, straws, and feathers, being bulky, but shallow, 

 and not neatly arranged. The eggs are two or three, of an 

 elongated form, pure white, their average length one inch, 

 their greatest breadth seven and a half twelfths. They are 

 deposited from the beginning to the middle of June, and the 

 young are abroad by the end of July. Only one brood is reared 

 in the season. The Swifts take their departure from the mid- 

 dle to the end of August, thus residing with us only about 

 three months and a half. 



As the insects on which they live are generally very small, 

 they do not swallow each as it is caught, but collect a number 

 previous to the act of deglutition, for at whatever period they 

 are shot, one generally finds insects in their mouths. When 

 collecting food for their young, they do not return to the nest 

 so frequently as the Swallows, but accumulate a considerable 

 quantity at a time. I have never found any particles of gravel 

 or sand in their gizzards, of which the hard cuticular lining is 

 of a reddish-brown colour, as in most birds that feed on insects, 

 such as Wagtails, Pipits, and Warblers. The insects on which 

 they feed are various species of Coleoptera, Ephemerre, Phrj'- 

 ganeae, and occasionally LibelluLne and Muscre. 



White seems to be the first who observed that Swifts copu- 

 late on wing. " If any person,"" he says, " would watch these 

 birds of a fine morning in May, as they are sailing round at a 

 great height from the ground, he would see every now and 

 then, one drop on the back of another, and both of them sink 

 down together for many fathoms with a loud piercing shriek. 



