348 ANIMAL LIFE IN THE YOSEMITE 



seconds and another fully a minute. These notes remind one of the quaver- 

 ing call of the Screech Owl save that they are longer continued, on one 

 key, and uttered in almost the same cadence throughout. 



Each individual nighthawk seemed to have a favorite resting place 

 to which it returned regularly. This was on the gravel, at the side of, 

 and partially shaded by, a lupine or other bush. The male bird of the 

 pair mentioned was seen to return to the neighborhood of such a spot 

 time and time again, and upon flushing him directly and thus ascertaining 

 its exact location, the site was found to be marked by an accumulation 

 of droppings of characteristic form — each a small spiralled mass composed 

 chiefly of finely triturated insect remains. 



Careful scrutiny of the ground within 100 feet of this male bird's 

 'roost' eventually led to the discovery of a 'nest' with two eggs which 

 were being incubated by the female. The latter flushed when the observer 

 was about 50 feet away, and then made off along the ground with a peculiar 

 dragging flight, her wings fluttering and held downwards from the body, 

 almost touching the ground. When she flew off, the male, who had been 

 resting in his favorite spot, set up his crooning trill and continued it 

 with varying loudness for a full minute, until the female alighted upon 

 the gravel some distance away. When she again took wing he joined 

 and followed close in her wake as she flew about. This was at 1 :30 p.m., 

 in the heat of the day. 



The eggs lay 2 millimeters apart, and with their long axes at about 

 30° to each other, evidently just as the body of the female had fitted over 

 them. They were situated on a little sandy area, in a tract generally 

 covered with gravel. When not shielded by the female the eggs were fully 

 exposed to the heat of the sun. The slender branches of a dead weed, 

 300 millimeters away to the southwest, formed the only semblance of a 

 shelter. The bird could flush only to the northeast although she could 

 easily see all about her for a hundred feet or more. The eggs were found 

 (on May 6) to be about one-fourth incubated and one had a slight "stone 

 bruise" which was covered on the inside by hardened albumen. 



As is clearly seen in the illustration (pi. 45&) the coloration of the eggs 

 is strikingly like that of many of the water-rounded pebbles in the vicinity. 

 In all stages, egg, chick, and adult, the color scheme of the Texas Night- 

 hawk is to the last degree protective in character — a feature of evident 

 usefulness to a species which spends all of its life, except when foraging, 

 on tlie open ground. 



