342 LIFE HISTORIES OF NORTH AMERICAN BIRDS. 



Its general habits, food, etc., are very similar to the other subspecies of this 

 genus. Mr. F. Stephens writes me: "The Mexican Horned Lark breeds in most 

 of the larger valleys (if not too wet) throughout southern California, from sea 

 level to the pines. Near Riverside they nest in the orchards and vineyards, but 

 in other localities the nesting site is usually away from the brush. A nest con- 

 taining two eggs was found by me in a salt marsh at False Bay, near San Diego, 

 California, which was situated similarly to those of Ammodramus beldingi." 



Mr. Rollo H. Beck writes that this subspecies is a common resident in 

 Santa Clara County, where it breeds in considerable immbers, both in fields 

 adjoining sloughs that connect with San Francisco Bay and in the hills on 

 the eastern side of the valley. Mr. Charles A. Allen reports it as common in 

 Marin County, and several males shot by him near Nicasio on April 29, 1890, 

 sent me for examination, are referable to this subspecies. Nearly all of the eggs 

 of this subspecies in the United States National Museum collection were taken 

 in the vicinity of Santa Cruz, California. A set from the extreme southern 

 limits of its range, taken by Mr. E. W. Nelson near Perote, Vera Cruz, Mexico, 

 is jDrobably referable to this subspecies. This nest, found on June 6, 1893, con- 

 tained only two eggs, in which incubation had commenced; these are somewhat 

 larger than eggs from southei'n California. The nesting habits of the Mexican 

 Horned Lark are quite similar to those of the other subspecies of this genus. 

 Occasionally a nest is found in a perfectly open situation; at other times it is 

 somewhat slieltered by a bunch of grass or weeds: and again it may be placed 

 in cultivated fields, etc. Mr. G. H. Atkinson took a nest containing four fresh 

 eggs near Santa Clara, California, on May 18, 1894, placed beside a row of 

 carrots, and composed entirely of dried grasses; and on June 14 another 

 nest, containing three fresh eggs, was found in a similar situation, probably built 

 by the same pair of birds. Nidification usually begins about the middle of 

 April, and probably two broods are regularly raised in a season, as fresh eggs are 

 frequently found in June. From two to four are laid in a set, generally three. 

 These resemble those of the previously described subspecies in coloration and 

 shape. 



The average measurement of twenty eggs in the United States National 

 Museum collection is 20.69 by 15.37 millimetres, or about 0.82 by 0.60 inch. 

 The largest egg of the series (one of the set from Perote, Vera Cruz, Mexico) 

 measures 23.11 by 15.24 millimetres, or 0.91 by 0.60 inch; the smallest, 19.05 by 

 15.24 miUimetres, or 0.75 by 0.60 inch. 



The type specimen. No. 21028 (PI. 5, Fig. 28), from a set of three eggs. 

 Men-ill collection, was taken near Santa Cruz, California, in April, 1879, and 

 has been selected as showing the ground color rather clearly. 



