New Birds from Western Mexico. 7 



orbits, pale creamy drab, shading abruptly into the purplish iridescence 

 which overlies remainder of crown and back of neck. This purplish 

 iridescence on the neck ends abruptly just in front of shoulders, and is 

 bordered by a narrow band of feathers tipped with greenish iridescence. 

 Entire dorsal surface, including wings and middle pair of tail feathers, 

 brown with an olive wash, except on tail and upper tail coverts. Throat 

 distinctly whitish ; remainder of lower side of neck and thence back over 

 chest delicate creamy lilac; abdomen and under tail coverts white with 

 a pale wash of buffy brown on edges of some of the feathers. Flanks dull 

 buffy brown ; tail feathers, except middle pair, blackish tipped with 

 white this tipping broadest on outer pair of feathers ; under wing coverts 

 and axillars pale cinnamon. Dimensions of type : wing, 152 ; tail, 109 ; 

 culmen, 18.5 ; tarsus, 33. 



Averages of Leptotila fulviventris brachyptera. (^ (5 specimens) : wing, 

 147.8; tail, 108.8; culmen, 16; tarsus, 31.3. $ (3 specimens): wing, 

 144.3; tail, 104.6; culmen, 15.6; tarsus, 30.6. 



Averages of L. capitalis. $ (5 specimens): wing, 152.5; tail, 110.6; 

 culmen, 17.9; tarsus, 322. $ (3 specimens): wing, 151.6; tail, 107; 

 culmen, 18.8; tarsus, 30.6. 



This species can be distinguished at once from its nearest mainland 

 relatives, P. fulviventris and P. fulviventris brachyptera, by its paler colors 

 and larger bill. Stragglers of typical brachyptera occur on the islands, as 

 shown by a specimen obtained there by Col. Grayson, now in the Na 

 tional Museum. This specimen is identical with the mainland bird and 

 shows no sign of approach to the insular species. 



Buteo borealis fumosus subsp. nov. Tres Marias Red-tailed Hawk. 



Type No. 156714, U. S. Nat. Mus., Biological Survey Coll., ad. tf, 

 Maria Madre Island, Mexico, May 6, 1897. Collected by E. W. Nelson 

 and E. A. Goldman. 



Description. Entire head and neck nearly uniform smoky brown, with 

 scarcely a trace of lighter markings on throat or chin. Back and wings 

 blackish brown ; breast and remainder of lower surface, except neck, 

 heavily marked with dull rusty, smoky brown, and dull whitish or buffy ; 

 no sign of lighter area on breast ; the markings on ventral surface are in 

 the form of indistinct barrings which are most clearly defined on the 

 tibia. Dimensions of type : wing, 375 ; tail, 206; culmen, 26; tarsus, 81. 



Averages of Buteo b. socorroensis. tf (2 specimens) : wing, 387.5; tail, 

 207.5; culmen, 25; tarsus, 80. 9 U specimen): wing, 425; tail, 221; 

 culmen, 30 ; tarsus, 86. 



Averages of B. borealis fumosus. $ (3 specimens) : wing, 373.3 ; tail, 

 207.3; culmen, 26; tarsus, 81.3. $ (1 specimen) : wing, 412; tail, 214; 

 culmen, 30 ; tarsus, 84.. 



The Tres Marias form is darker and more uniformly marked below, 

 and lacks the lighter areas on throat and breast that are found in B. 

 borealis socorroensis. On the dorsal surface fumosus is readily distinguish 

 able from socorroensis by the uniformly smoky brown head and neck, the 



