106 BULLETIN 19 7, UNITED STATES NATIONAL MUSEUM 



deep." Measurements of a nest at Tombstone, Ariz., as given in F. C. 

 Willard's notes, are somewhat smaller: Diameter outside 3% inches, 

 inside 21^ inches; depth outside II/2 inches, inside 1 inch. Dr. Ever- 

 mann (1882) remarked that "the cavity in most of them is more nearly 

 the form of an ellipse than a circle. The wall of the nest is generally 

 thicker at one end of the ellipse than elsewhere." 



In parts of central Lower California the breeding season seems to be 

 intermediate between those of the two distinct regions in the United 

 States, as indicated in a report by Grilling Bancroft (1930) : 



These birds are plentiful in Jose Maria Caiion, but they become progressively 

 less so as one travels eastward. They are gregarious to the extent of perhaps 

 a dozen pairs in especially favored spots where the mesquite is at its best and food 

 supply is exceptional. They are absent, locally, from altitudes of over a thousand 

 feet. 



The breeding season opens the middle of April but does not reach its height 

 for another mouth. The season is 6 weeks later than is that of the phalnopepla 

 of the Colorado Desert, but it is slightly in advance of that of the birds of the 

 San Diegan District. In California we expect to find the nests resting against 

 the larger limbs of trees. In the San Ignacio region nearly all were placed in 

 mistletoe or suspended beneath it. That condition, however, is not peculiar to 

 this region, for I have observed the same thing near Ensenada. 



The nests were typical, small and built of fine gray plant down reinforced with 

 tiny twigs and leaves. They were ordinarily placed 8 to 12 feet above the ground, 

 though some were much higher. 



The number of eggs in a set is either two or three, the latter being more com- 

 mon and an exception to the very general rule that the San Ignacio birds lay more 

 sparingly than do their northern counterparts. The variations in the individual 

 eggs, in shape, size, and markings, were pronounced. Some were practically 

 spherical and others extremes of elongation. 



With the laying of the eggs the female begins to assume a more 

 direct responsibility in the nesting operations, though the duty of 

 incubation seems to fall principally to the male, at least during the 

 daylight hours. The birds are rather easily disturbed while on the 

 nest, and they fly about with anxious cries as long as the intruder 

 remains near. 



Eggs. — Mr. Blaisdell (1893) says: "The eggs are two (frequently), 

 three (usually), or four (rarely), in number." While sets of four 

 seem to be exceedingly unusual, the relative frequency of two and three 

 egg sets may be in part a matter of locality. In relating his early ex- 

 periences in Ventura County, Calif., Dr. Evermann (1822) wrote: 



Six of the seven nests contained three eggs each, the other but two. Dr. Cooper 

 and Capt. Bendire, the only naturalists who appear to have found the nest of this 

 species before me, never found more than two eggs in a set. Dr. Cooper found a 

 single nest near Fort Mojave, on April 27. Capt. Bendire, in the season of 1872, 

 found fourteen nests in the vicinity of Tucson, Arizona, and not one contained 

 more than two eggs, "and in three instances the nest contained but a single egg 

 and tlie bird hard setting upon that." * * ♦ He says: "The small number 

 found by me is unquestionably due to the fact that in southern Arizona they raise 



