April, 1919] Subspecies of Passerculus Rostratits 353 



Passerculus rostratus halophilus (McGregor). 



Ammodramus halophilus McGregor, Auk, XV, No. 3, July, 1898, p. 265 (Abreo- 

 jos Point, Lower California). 



Chars, subsp. — Similar to Passerculus rostratus guttatus, but upper 

 surface duller, darker, and more greenish (less purely grayish) , the dark 

 streaks on pileum and interscapulum less sharply defined; sides of the 

 head, including particularly the supraloral region, more suffused with 

 yellowish; streaks on lower parts heavier, more blackish, and without 

 brownish edgings. 



Measurements * — Maleif wing, 66.80-70.61 (average, 69.09) mm.; 

 tail, 42.93-52.32 (50.29); exposed culmen, 12.70-12.95 (12.62); height 

 of bill at base, 6.35-7.62 (6.60); tarsus, 20.32-22.01 (21.59); middle 

 toe without claw, 15.49-17.02 (16.00). 



Female:J wing, 63.50-69.60 (average, 64.77) mm.; tail, 45.21-51.05 

 (47.50^; exposed culmen, 12.19-13.21 (12.70); height of bill at base, 

 6.10-6.86 (6.35); tar.sus, 20.32-22.35 (21.34); middle toe without claw, 

 14.48-16.76 (15.75). 



Type locality: — Abreojos Point, central western Lower 

 California. 



Geographic distribution: — The southern half of the western 

 coast of Lower California. Breeds at Abreojos Point, central 

 western Low^er California and probably also at San Juanico 

 Bay somewhat farther south. Winters south to Cape San 

 Lucas. 



Remarks. — This race differs from Passerculus rostratus 

 rostratus so very strongly in its darker, more greenish upper 

 surface and in its slenderer bill that no special comparison is 

 necessary. A careful examination of the type series and also 

 of winter birds from the Cape San Lucas region, and their 

 comparison with both Passerculus rostratus rostratus and 

 Passerculus rostratus guttatus show that Passerculus rostratus 

 halophilus is an excellent subspecies. The three races of this 

 species may be readily distinguished by the color of the upper 

 surface alone, since Passerculus rostratus rostratus is a brownish 

 bird, Passerculus rostratus guttatus a grayish form, and Passer- 

 culus rostratus halophilus decidedly greenish. Mr. William 

 Brewster's objections! to the recognition of Passerculus rostratus 

 halophilus have been fully met by the acquisition of a good 

 series of breeding examples of Passerculus rostratus guttatus, 



* Taken from Ridgway, Bull. U. S. Nat. Mus., No. 50, part I, 1901, p. 202. 



t Nine specimens, from Lower California. 



X Twelve specimens, from Lower California. 



I Bull. Mus. Comp. Zool., XLI, No. 1, September, 1902, pp. 139-140. 



