16 LIFE HISTORIES OP NORTH AMERICAN BIRDS. 



cation lasts through the summer months, two and occasionally three broods being 

 raised in a season. While the first set of eggs laid by such species as rear more 

 than one brood in a season is usually larger in number than subsequent ones, 

 it seems to me that with the Road-runner the reverse is the case. 



During the month of April, 1872, I found several nests, none of which 

 contained more than three eggs, all well incubated when found; similar small 

 sets were found during the first half of May, while in June and July the sets 

 numbered from four to six eggs, the latter the largest sets observed by me in 

 Arizona. The following explanation may account for this : 



In southern Arizona, during the spring months, insects and reptiles, which 

 form the bulk of the food of these birds, are rather scarce, while in June, as 

 soon as the rains commence, and later through the summer, suitable food is far 

 more abundant and a larger family can be much more readily cared for, and I 

 am of the opinion that these birds know this and act accordingly. Occasionally 

 a larger number of eggs is found, however, and Lieut. H. C. Benson, Fourth 

 Cavalry, United States Army, writes me that he saw a nest of this species, near 

 Fort Huachuca, containing six young birds, all of different sizes, and two eggs; 

 the largest of the young was about ready to leave the nest, and the smallest 

 only a day or two old. 



Their nesting sites are quite variable. In southern Arizona the majority 

 of nests found by me were placed in low mesquite trees or thick bushes, and in 

 different species of cacti, such as the prickly pear, cholla, and others. Occasion- 

 ally one of their nests is placed on top of a mesquite stump, surrounded by 

 green sprouts, or in a hackberry or barberry bush. I found one nest in a palo 

 verde tree, and another in a willow thicket ; in the latter case the birds did not 

 build their own nest, but appropriated one of the Crissal Thrasher, Harporhjn- 

 chus crissalis. Mr. F. H. Fowler writes me from Fort Bowie that he saw a nest 

 near there, placed in the hollow of a dead stump. 



In Texas the Roadrunner sometimes nests in ebony bushes, and in Cali- 

 fornia it has been known to use the nest of the California Jay, Aplielocoma 

 calif ornica, in oak trees, sometimes fully 16 feet from the ground. Usually the 

 nests are placed from 3 to 8 feet from the ground, and only in rare instances 

 higher. Sometimes they are found in quite open situations, but generally they 

 are well concealed from view. 



A typical nest of the Road-runner may be described as a rather flat and 

 shallow but compactly built structure, abqut 12 inches in diameter and varying- 

 in thickness from 4 to 6 inches, with but little depression interiorly. The 

 ground work consists of sticks from 5 to 10 inches long, lined more or less 

 regularly with finer material of the same kind and finished off with dry grasses. 

 Occasionally bits of dry cow or horse dung', a few feathers, the inner bark of 

 the cottonwood, dry mesquite- seed pods, bits of snake skin, and small grass 

 roots are used, and now and then no lining is found, the eggs lying on a simple 

 platform of twigs. 



The number of eggs to a set varies in different localities from two to nine, 

 and occasionally as many as twelve have been found in a nest, possibly the 



