52 BIRDS OF ILLINOIS. 



the neck and jugulum indistinctly streaked with grayish, the sides, flanks, and crissum 

 sometimes sparsely streaked. Young: Back and scapulars black, the feathers broadly 

 bordered with rusty ochraceous, this becoming paler, or even white, on the ends of some of 

 the feathers; lesser and middle- wing coverts bordered with buff; rump plain brownish 

 slate; upper tail-coverts darker, tipped with rusty; crown light rusty, streaked with black. 

 Head and neck (except crown and throat) dull dingy buff indistinctly streaked with dusky; 

 remaining lower parts, including throat, white, the breast and belly with numerous irreg- 

 ularly cordate spots of black, the flanks, crissum, and lining of the wing immaculate. "Bill 

 and feet black ; iris dark brown." (Audubon.) 



Total length about 8.50 inches; wing, 4.60-4.95; culmen, 1.40-1.75 tarsus, 1.00-1.15: middle 

 toe, .70-.80. 



There is a considerable amount of individual variation in this 

 species, especially noticeable in the extent and continuity of the 

 black abdominal area, the distinctness of the black markings 

 above, and the depth of the rufous tint; not unfrequently the 

 latter is mixed with grayish. In the winter plumage some ex- 

 amples have the sides and crissum narrowly streaked, while in 

 others these parts are immaculate. 



The Red-backed Sandpiper is an abundant species during the 

 spring and fall migrations. Mr. Nelson records it as "a very 

 abundant migrant" in Cook county, and says that it "arrives 

 in full breeding plumage the last of May, and is found about 

 muddy pools and flats near the Lake until the 5th of June. 

 Returning in winter dress during September it remains well into 

 October. At this season it is generally found in small parties, 

 while in spring the flocks often contain hundreds of individuals." 



Genus EREUNETES Illiger. 



Ereunetes Illiger, Prodromus, 1811, 262. Type, E. petriftcatus Illig.,= Tringa inisilla 

 Linn. 



Chae. Size small; anterior toes webbed at the base; a well-developed hind toe. Bill 

 about as long as or a little longer than the head, straight, somewhat expanded at the end, 

 about as long as the tarsus; middle toe more than half as long as the tarsus; bare portion 

 of tibia nearly equal to the middle toe. 



The bill of Ereunetes is quite stout and considerably expanded, 

 by which it is really distinguished from Tringa mvrmtilla inde- 

 pendently of the semipalmated feet. The tarsus and middle toe 

 are about equal; the tibia denuded anteriorly for about two 

 thirds the length of tarsus. The basal membrane of toes is 

 more scalloped out interiorly than exteriorly; the notch exter- 

 nally not quite as deep as to the first joint, although the 



