THE WHITE-HEADED WOODPECKER. 73 



I consider the White-headed Woodpecker a rather silent and moi'e sedate 

 bird than most of the otlier members of this family, the only note I liave heard 

 it utter being- a sharp, clear "witt-witt" as it ])asses from one tree to another. 

 During- the winter its food consists principally of spiders and insects and their 

 larvse; and in summer, as Mr. Charles A. Allen, of Nicasio, California, informs 

 me, "It feeds its young- on the larg-e black ants with which all tlie dead pines 

 and stumps are covered at tliat time of year." 



Niditication usually begins about the middle of May and continues through 

 June. The sexes relieve each other in the preparation of the nesting site, which 

 is usually located in a dead stub of a pine or fir; one that is parti }^ decayed 

 seems to be preferred as it rarely excavates one in solid, hard wood. The nesting- 

 sites are seldom situated over 15 feet from the ground, and sometimes as low 

 as 2 feet. The enti-ance hole is about IJ inches wide, perfectlj^ circular, and 

 just large enough to admit the bird; the inner cavity gradually widens towards 

 the bottom, and is usually from 8 to 12 inches deep, the eggs lying on a slight 

 layer of fine chips, in which tliey become well embedded as incubation advances. 

 Occasionally a rather peculiar site is selected. Mr. Charles A. Allen found a 

 nest of this species in a j)Ost in one of tlie snow sheds on tlie Central Pacific 

 Railroad, between Blue Canyon and Emigrant Gap, about 40 feet from the 

 entrance of the shed, and some thirty trains passed daily within a few feet of 

 the nest, which contained six eggs when found. Incubation la.sts aboiit fourteen 

 days, and both sexes assist in this, as well as in the care of the young, which are 

 born blind and remain so until about half p-rown. 



The number of eggs to a set varies from three to seven, sets of four being 

 most common. There is only a single set of five in the United States National 

 Museum collection, taken by Mr. L. Belding, at Big Trees, California, on June 

 8, 1879; but Mr. Charles A. Allen writes me that he has found seven eggs in 

 one of their nests. These vary in shape from ovate to short ovate; the shell 

 is 23ure white, fine grained, and only moderately glossy. When fresli juid 

 imblown they are of a delicate pinkish tint and semitranslucent, and the Aolk 

 can be plainly seen; as incubation advances they become more and more 

 opaque. 



The average measurement of forty-one specimens in the United States 

 National Museum collection is 24 by 18.07 millimetres, or about 0.95 by 0.71 

 inch. The largest eg'^ of the sei'ies measures 25.40 by 19.30 millimetres, or 1.00 

 by 0.76 inch; the smallest, 21.84 by 17.78 millimetres, or 0.86 by 0.70 inch. 



The type specimen. No. 19436 (not figured), from a set of four eggs, Ben- 

 dire collection, was taken by the writer, near Camp Harney, Oregon, on May 

 6, 1877. 



