100 BULLETIN OF THE NUTTALL. 



always described the bird with all the lateral rectrices narrow, and 

 destitute of any notch. 



I have not said anything, in comparing the species, about the 

 color of the back, as I consider this is not altogether a satisfactory 

 character by which to distinguish the birds, though Mr. Henshaw 

 makes it one of his principal ones. Latham, in his original descrip- 

 tion, states that the " crown " was " glossy gi'een," and also that there 

 was a "greenish gloss between the wings." In the first place, the 

 females of both are entirely green in their upper surface, and this is 

 not always pure green, as I have specimens now before me, collected 

 by Boucard at Oaxaca, Mexico, in which the back is a yellowish- 

 bronze, precisely like young males in my collection from California 

 of the other form, collected by Dr. Heermann. Again, I have 

 young males, also collected by Boucard at Oaxaca, which have the 

 back of such a curious reddish-cinnamon that it is difficult to say 

 •what color it exactly is ; and Mr. Henshaw says, in his article 

 (p. 55), that " in California, however, where the aS'. rufus occurs in 

 its typical condition, that is, with an unmixed rufous back, specimens 

 are not uncommonly foimd ivhich exhibit a strong a2)2^roach to the colora- 

 tion of S. alleni " ; although, as he farther says, " they never apppear 

 to pass beyond a certain point.", It is, however, indisputable, that the 

 two species do vary in the amount of green upon their upper sur- 

 face, and also that at times they approach each other in coloration 

 so nearly that, were there no other differences existing, it would be 

 impossible to separate them. For this reason I do not place much 

 reliance upon the amount of green on the back as a specific charac- 

 ter. But there are other differences, I think, not mentioned by Mr. 

 Henshaw, to be observed in the females, by which this sex of the 

 two species can be distinguished. The female of the Mexican * 

 species has the rectrices broad. 



In addition to the superior width of its rectrices, the Mexican 

 bird has the lateral tail-feathers, for more than a third of their 

 length in the central poi'tion, jet black, the base light rufous, and 

 the tips white, so that when the tail is closed, and looked at from 



* I use the terms Mexican and Californian to designate the birds with broad 

 and narrow rectrices respectively, for the term rufous lias been so misapplied that 

 I cannot employ it at present without risk of adding to the confusion. At the 

 same time the bird called alleni is not restricted to California, as I have al- 

 ready shown, but goes as far north at least as Nootka Sound, and may iu winter 

 pass into Lower California, i)erhaps into Mexico. 



