Vol. XVIII"] OsGOOH, New North American Birds. I7Q 



igoi J ' -^ 



rather than ashj, feathers of the back having hardly ever any trace of 

 the black central markings often shown by migratoria. Remiges dark 

 olive brown, lighter and browner than in viigraforia. Throat white, 

 streaked with black, the streaks fewer, smaller, and less intensely black 

 than in migratoria. Breast, sides, axillars, and most of the under wing- 

 coverts light reddish brown of a slightly deeper shade than 'tawny 

 ochraceous' of Ridgway, whereas in migratoria these parts range from 

 Ridgway's 'cinnamon-rufous ' nearly to his 'burnt sienna.' Feathers of 

 the belly partly of the color of the breast, partly white. Flanks, legs and 

 under tail-coverts white, mixed with gray. 



"The differences between the females of the two forms are so closely 

 parallel to those of the males that a description of theni is unnecessary." 



The measurements given show the southern form to be considerably 

 smaller than the northern. 



Geographical range. — " Probably all the Robins breeding in the Caro- 

 linas and Georgia, outside of the mountain region of these States, will 

 prove to belong to the new form, while those that pass the summer among 

 the mountains, and in the low country of the adjacent region to the north 

 may be expected to be variously intermediate between it and true migra- 

 toria." 



NEW SUBSPECIES OF NORTH AMERICAN BIRDS. 



BY WILFRED H. OSGOOD. 



In identifying birds collected while working in the interests of 

 the Biological Survey, on the coast of British Columbia and 

 Alaska during the past season, comparisons have been made 

 which have led to the discovery of several well marked unde- 

 scribed subspecies. Several of these which do not come within 

 the scope of special reports now in preparation are here described. 

 For the freedom of the Biological Survey and the National 

 Museum collections, and for generous criticism, I am indebted to 

 Dr. C. Hart Merriam and Mr. Robert Ridgway. For the loan of 

 specimens I thank Mr. Joseph Grinnell and Mr. F. H. Fowler of 

 palo Alto, California. 



