118 BIEDS OF ILLINOIS. 



sharply defined; the streaks of the breast indistinct grayish-dusky, suffused with pale 

 fulvous, those of the back more strongly tinged with rusty. The two stripes on the 

 pileum dull grayish-dusky, instead of deep black. 



There is a slight average difference in proportions between birds of this species from 

 the Atlantic coast district and those from the country westward of the Alleghanies, but 

 the difference is scarcely sufficient to warrant their separation as races. The average 

 measurements of specimens from the two regions are as follows: 



Atlantic coast specimens (true M. varia}. Male: Wing. 2.72-2.88 (average 2.78); tail, 1.92-2.20 

 (2.07); culmen, .45-. 50 (.48); bill from nostril, .32-. 40 (.37); tarsus, .60-. 68 (.65); middle 

 toe, .50-. 58 (.54). Female: 2.70; 2 .-2.05 (2.0J); .45-. 48 (.46); .36-. 38 (.37); .C8-.70 (.69); .50. 



Mississippi Valley specimens (M. varia borealis). Male: Wing, 2.70-2.90(2.80); tail, 2. -2. 24 

 (2.09); culmen, .40-. 48 (.44); bill from nostril. .30-. 38 (.32); tarsus, .62-. 65 (.63); middle 

 toe, .49-. 58 (.52). Female: 2.60-2.75(2.65); 1.92-2. (1.96); .40-. 45 (.42); .32; .66; .50-. 56 (.53) 



The above figures are based upon the careful measurement of 9 adult males and 2 

 adult females from each region, and, while they show that the difference is not abso- 

 lutely constant, they show that the eastern bird averages decidedly larger (except in 

 length of wing and tail), the difference being especially noticeable in the greater length 

 of bill and feet. 



The longer-billed form winters in Florida and the West Indies, the other in Mexico. 



This sprightly and pretty little bird is very common in dry woods, 

 where it may be seen ascending or descending the trunks of trees 

 lin the manner of a creeper or nuthatch. Its nest is built upon the 

 ground, imbedded among dry leaves, and as a rule so artfully con- 

 cealed as to be discovered only by accident. 



GENUS PROTONOTARIA BAIRD. 



Protonotaria BAIRD, Birds N. Am. 1858, 239. Type, Motacilla citrea BODD. 



GEN. CHAR. Bill longer than the middle toe and claw, distinctly notched, all the out- 

 lines nearly straight. Wings much longer than the rather short, rounded tail. Tarsus 

 decidedly longer than the middle toe and claw. Lower tail-coverts reaching nearly to 

 the end of the tail (on account of the shortness of the latter). 



This genus is most closely related to the genera Helinaia and 

 Helmitheros, especially the former, but may be immediately distin- 

 guished by the distinctly notched bill, and brilliant colors, there 

 being in the latter respect much resemblance to the Helminihophilee, 

 particularly H. pinus. The single known species is one of the largest, 

 and in some respects the finest, of the warblers, and is very peculiar 

 in its habits, frequenting wooded swamps or the willow-grown bor- 

 ders of ponds in the bottom lands, and nesting in holes of stumps 

 or dead trees, like the Titmice. 



