XANTUS'S GNATCATCHER 373 



[It is] widely spread and decidedly common. There was no association and no 

 region where the presence of a pair of these little scolds could not be expected. 

 They were most plentiful west of Jos6 Maria Canon. They seemed equally at 

 home in the thickest brush and on the most open plains. Yet we found only five 

 occupied nests and were able to save but one set of eggs. 



The nests are cups, rather thin and quite deep. They are so extremely neat 

 and trim and blend so well into the background that it is difficult to see them, the 

 first time. They are usually placed in the center of some sage-like bush about 

 three feet from the ground. They rest on both a lateral and a horizontal branch. 

 One exceptional site was the heart of a mistletoe in a mesquite, well hidden by the 

 parasite, at a height of twelve feet. 



Fresh eggs are most numerous about the middle of May, and the season is ex- 

 ceptionally short. The number in a clutch, within our limited experience, was 

 three. 



There is a set of three eggs in the Doe collection, taken by Mr. 

 Bancroft, near San Ignacio Lagoon, on June 5, 1932; the nest was three 

 feet above the ground, well concealed near the upper center of a tall 

 shrub, back in the hinterland and well away from the lagoon. 



The eggs are evidently indistinguishable from those of the northern 

 forms. The measurements of 6 eggs average 15.2 by 11.5 millimeters; 

 the eggs showing the four extremes measure 15.5 by 11.5, 14.8 by 11.9, 

 and 15.0 by 11.0 millimeters. 



POLIOPTILA MELANURA ABBREVIATA Grinnell 



XANTUS'S GNATCATCHER 

 HABITS 



This local race of the Cape district of Lower California remained for 

 long unrecognized as distinct from the other races of the species. 

 It remained for Dr. Joseph Grinnell (1926) to describe and name it. 

 He says of it: "In general character similar to Polioptila melanura 

 melanura (see Ridgway, 1904, p. 731, under Polioptila plumbed) of 

 southeastern California and southern Arizona, but (in both sexes) 

 tail decidedly shorter, bill somewhat larger, leaden hue of dorsum 

 slightly deeper, and lower surface slightly more imbued with gray, 

 not so clearly white." 



Of its range he says: "So far as now definitely known, only the 

 southern end of the Lower Californian peninsula, from San Jose del 

 Cabo and Cape San Lucas north to La Paz." 



Earlier writers referred the birds of the Cape region to plumbea, 

 now known as melanura, but William Brewster (1902) remarks: 

 "All my Lower California specimens seem to have shorter tails than 

 the birds which inhabit Arizona and Texas." Evidently all his birds 

 came from the Cape region, where Mr. Frazar regarded it as rather 

 rare. 



J. Stuart Rowley writes to me: "I met with these birds in the Cape 



