12 LIFE HISTOEIBS OF NORTH AMERICAN BIRDS. 



Lieut. H. C. Benson, Fourth Cavalry, U. S. Army, found the Masked Bob 

 Wliite fairly abundant near Campos and Bacuachi, Sonora, securing a number 

 of specimens in the summer of 1886, and he writes me that they only 

 frequented cultivated fields there, where wheat and barley had been raised. 

 He also found another species of Partridge associated with these birds near 

 Campos, which probably crosses our border also. This Partridge was recently 

 described by Mr. R. Ridgway, in Forest and Stream of March 3, 1887, and 

 named ^^ CaUipepla elegans bensoni," in honor of its discoverer. 



Nothing positive has been known about the nest and eggs of the Masked 

 Bob White till the present season, though one of their nests containing six eggs 

 was found some years ago. They were allowed to remain in hope of seeing 

 the number increased, and Avhen visited at another time they had hatched. 

 The nest as described to Mr. Brown was a shallow excavation alongside a tuft 

 of grass. The eggs were white and unspotted. In the spring of 1890 Mr. 

 Brown succeeded in obtaining one of these eggs cut from the oviduct of the 

 female, as well as a set of eleven eggs said to belong to this species. These 

 eggs were found early in May in a similar situation ixi the vicinity of Arivaca. 

 The egg of the Masked Bob White is white, unspotted, subpyriform in shape, 

 and their average measurement is 31 by 25 millimetres. 



Since the foregoing was written, Mr. Otho C. Poling writes me from Fort 

 Huachuca, Arizona, as follows: "I first met with the Masked Bob White on 

 May 24, 1890, in a series of low foothills extending off to the northwest of the 

 Huachuca Moiintains, and ending in a somewhat higher range of hills called 

 the Canella Range, being the northwestern termination of tlie Huachucas. 

 Most of these hills are thickly grown up Avith juniper, cedar, manzanita, stunted 

 oaks, pines, and with a heavy growth of grass. While riding along one of 

 these grassy ridges I flushed what I supposed was a "Fool Quail," Cyrtonyx 

 montesumcB. I at once staked my horse, and on shooting the bird I found it to 

 be a male of the Masked Quail. I continued the search and had spent a half 

 hour or more, when, as I passed within 2 feet of a mescal plant. Agave ameri- 

 cana, I suddenly flushed the female from underneath it. . I first shot her and 

 then expected to find the nest; but after searching for several hours and failing, 

 I gave it up. The female contained an egg which was fully developed and 

 would probably have been laid within half an hour. I searched for the nest 

 of this species on the two succeeding days as well, but made no further discov- 

 eries. The single egg of Colinus ridgivayi obtained by me is pure white and 

 measures 31 by 24 millimetres. 



"The Canella Range is about 25 miles north of the Mexican border. Two 

 more specimens of the Masked Quail, both females, were shot about June 10, 

 in the Huachuca Mountains, near the middle of the range, at an elevation of 

 about 6,000 feet. The birds were found in a canon about 15 miles north of the 

 border, on the northeastern slope of the range." 



From the foregoing it would appear that the Masked Bob White is confined 

 to a narrow strip of country along our southwestern border, and is nowhere as 



