° s ' RlDGWAY, Geographical Variation in Sialia mexicana. 1^9 



variation in this sex, affecting chiefly the blue color, which varies 

 from light cobalt or azure to very nearly a verditer hue, with a 

 decided greenish tinge to the edges of the rectrices ; the distinct- 

 ness of blue tinge to color of pileum and hind-neck, and the color 

 of the back, which is always distinctly browner than adjacent 

 parts, and, strange to say, sometimes more distinctly brown in 

 coast specimens than those from the interior. 



3. Sialia mexicana anabelae Anthony. 



San Pedro Bluebird. 



Sialia mexicana anabelce Anthony, Proc. Cal. Ac. Sci. 2d ser. II, Oct. 

 18S9, 79 (San Pedro Martir Mts., Lower Cal.) ; Zoe, IV, No. 3, 

 1893, 2 47 ( m text, under S. mexicana) . — A. O. U. Comm. Auk, 

 Jan. 1S90, 66. 



Geographical Range. — San Pedro Martir Mountains, Lower Cali- 

 fornia (resident) . 



Subsp. Char. — Differing from true 5. mexicana in shorter wing, the 

 tail averaging a little longer; lighter blue above ; lower parts with much 

 more blue ; the chestnut color often confined to a patch on each side of the 

 breast. Differing from S. in. occidentalis in longer wing and tail, larger 

 bill, and less extent of the chestnut color, both above and below, that of 

 upper parts never extensive, and usually nearly, often quite, wanting, that 

 of under parts usually confined to a patch on each side of breast. Females 

 to be distinguished from those of 5. m. occidentalis only (?) by stouter bill. 



Adult male in spring (type, coll. A. W. Anthony, San Pedro Martir 

 Mts., Lower California, May 6, 1SS9) : Upper parts entirely rich smalt- 

 blue, inclining to ultramarine in certain lights, without even a trace of 

 blue on back or scapulars; greater part of inner webs of tertials and tips 

 of all the remiges (broadly) dull black ; shafts of remiges and rectrices 

 glossy black. Lower parts rich blue (intermediate between smalt and 

 ultramarine), nearly as intense anteriorly as color of upper parts, but 

 fading to light grayish blue on belly, which becomes lighter, scarcely 

 bluish, gray centrally; under tail-coverts campanula-blue. A patch of 

 chestnut on each side of breast, separated by a bright blue space about 

 0.S0 of an inch wide. Bill, legs, and feet deep black. Total length 

 (skin), 6.20; wing, 4.32 ; tail, 2.90 1 ; exposed culmen, 0.47; tarsus, 0.75; 

 middle toe, 0.55. 



1 Average and extreme measurements of wing and tail of 41 adult males are as 

 follows : Wing : Average, 4.29 ; longest, 4.48 ; shortest, 4.10. 



