Henshaw on Selasphorus alleni. 11 



crossed by numerous (seven or eight, the number rather indefinite, how- 

 ever) bai-s of black ; these bars becoming broken towards the ends, and 

 gradually obsolete at the bases of the feathers ; the ground-color occasion- 

 ally paler along the posterior edge of the blackish bar. Whole side of the 

 head and entire lower parts white, the sides faintly tinged with buff. A 

 distinct dusky stripe along upper edge of auriculars, below the very con- 

 spicuous and continuous white superciliary stripe. Bill and feet plum- 

 beous-dusky. Wing, 2.30 - 2.45 ; tail, 2.30 - 2.45 ; bill, from nostril, 

 .45 - .48 ; culmen, .75 - .78 ; tarsus, .80 ; middle toe, .50. 



Habitat. Tres Marias Islands, off the western coast of Mexico. 



Types. 37,329, ^ (Jan. 1865), 50,817, and 50,818 (U. S. Nat. Mus. 

 Catal.), Tres Marias ; Col. A. J, Grayson. 



The principal characteristics of this form and the typical one may be 

 contrasted as follows : — 



a. felix. Throat bordered along each side by a wide and conspicuous 

 stripe of black ; whole sides of neck and also auriculars distinctly streaked 

 with black ; entire lower parts, except throat, buff, deepest along sides. 

 Wing, 2.10-2.35 ; tail, 2.25-2.35 ; bill, from nostril, .39 -.42 ; tarsus, 

 .80 -.90 ; middle toe, .50-52.* ifa6., mainland of Western Mexico, from 

 Mazatlan to Oaxaca. 



0. lawrencii. Black markings of cheeks, etc., usually entirely absent, 

 very rarely barely indicated ; lower parts, except sides, pure white. Wing, 

 2.30 - 2.45 ; tail, 2.30 - 2.45 ; bill, from nostril, .45 - .48 ; tarsus, .80 ; 

 middle toe, .50.t Hab., Tres Marias Islands, Western Mexico. 



ADDITIONAL EEMARKS ON SELASPHORUS ALLENI. 



BY H. W. HENSHAW. 



In his remarks ou Selasphorus alleni, in the October number of 

 the Bulletin, Mr. D. G. Elliot attempts to prove that in selecting this, 

 the Green-backed,! or, as he calls it, the Californian form, for naming, 

 I committed an error, this, according to him, being the bird described 

 by Gmelin as the Trochilus rit/us, and hence, as he claims, it was 



* Five specimens measured, all from Mazatlan. 



+ Three specimens measured. 



X In this article, by the Green-backed Hummer will be understood the 

 recently recognized form from California ; the Rufous-backed bird being the 

 old and better known form from Mexico and the West Coast generally. The 

 coloring of the adult males renders these names sufiBciently appropriate. 



