620 
SWALLOW TRIBE. 
parts of Georgia. They are now commonly seen towards 
evening, in pairs, sailing round in sweeping circles, high 
in the air, occasionally descending lower to capture fly- 
ing insects, chiefly of the larger kind, such as wasps, 
beetles, and moths. About the middle of May, or later, 
the female selects some open spot in the woods, the cor- 
ner of a corn-field, or dry gravelly knoll, on which to de- 
posit her eggs, which are only 2, and committed to the 
bare ground, where, however, from the similarity of their 
tint with the soil, they are, in fact, more secure from ob- 
servation than if placed in a nest. They are nearly oval, 
of a muddy bluish-white, marked all over with touches of 
an umber color. Here the male and his mate reside dur- 
ing the period of incubation, roosting at a distance from 
each other on the ground, or in the neighbouring trees ; 
and in consequence of the particular formation of their 
feet, like the rest of the genus, they roost or sit lengthwise 
on the branch. During the progress of incubation, the 
male is seen frequently, for some hours before nightfall, 
playing about in the air over the favorite spot, mounting 
in wide circles, occasionally propelled by alternate quick 
and slow vibrations of the wings, until at times he nearly 
ascends beyond the reach of sight, and is only known by 
his sharp and sudden squeak, which greatly resembles 
the flying shriek of the towering Swift. At other times 
he is seen suddenly to precipitate himself downwards for 
60 or 80 feet, and wheeling up again as rapidly ; at which 
instant a hollow whirr, like the rapid turning of a spin- 
ning-wheel, or a strong blowing into the bung-hole of an 
empty hogshead, is heard, and supposed to be produced 
by the action of the air in the open mouth of the bird. 
He then again mounts as before, playing about in his 
ascent, and giving out his harsh squeak, till in a few 
moments, the hovering is renewed as before ; and at this 
