NIGHT HA WK. 



I6 5 



about, high in air, pursuing their prey, wasps, flies, beetles, 

 and various other winged insects of the larger sort. About 

 the middle of May the female begins to lay. No previous 

 preparation or construction of a nest is made, though doubt- 

 less the particular spot has been reconnoitred and determined 

 on. This is sometimes in an open space in the woods, fre- 

 quently in a ploughed field, or in the corner of a cornfield. 

 The eggs are placed on the bare ground, in all cases on a dry 

 situation, where the colour of the leaves, ground, stones, or 

 other circumjacent parts of the surface, may resemble the 

 general tint of the eggs, and thereby render them less easy to 

 be discovered. The eggs are most commonly two, rather 

 oblong, equally thick at both ends, of a dirty bluish white, and 

 marked with innumerable touches of dark olive brown. To 

 the immediate neighbourhood of this spot the male and female 

 confine themselves, roosting on the high trees adjoining 

 during the greater part of the day, seldom, however, together, 

 and almost always on separate trees. They also sit length- 

 wise on the branch, fence, or limb on which they roost, and 

 never across, like most other birds : this seems occasioned by 

 the shortness and slender form of their legs and feet, which 

 are not at all calculated to grasp the branch with sufficient 

 firmness to balance their bodies. 



As soon as incubation commences, the male keeps a most 

 vigilant watch around. He is then more frequently seen 

 playing about in the air over the place, even during the day, 

 mounting by several quick vibrations of the wings, then a few 

 slower, uttering all the while a sharp, harsh squeak, till 

 having gained the highest point, he suddenly precipitates 

 himself, head foremost, and with great rapidity, down sixty 

 or eighty feet, wheeling up again as suddenly ; at which 

 instant is heard a loud booming sound, very much resembling 

 that produced by blowing strongly into the bunghole of an 

 empty hogshead, and which is doubtless produced by the 

 sudden expansion of his capacious mouth while he passes 

 through the air, as exhibited in the figure on the plate He 



