402 Field Museum of Natural History — Zoology, Vol. IX. 



Knot. 



Upper tail coverts. 



Length, 10.60; wing, 6.70; tarsus, 1.25; bill, 1.30. 



The Knot occurs sparingly in Illinois and Wisconsin during the 

 migrations. Nelson gives it as a regular migrant, but not common. 

 Kumlien and Hollister say : "Thirty years ago a rather common mi- 

 grant in May and June and more sparing in Autumn. Of late years 

 decidedly rare at any season." (Birds of Wisconsin, 1903, p. 45.) 



Genus ARQUATELLA Baird. 



113. Arquatella maritima (Brunn.). 



Purple Sandpiper. 



Tringa maritima Briinn., A. O. U. Check List, 1895, p. 87. 



Distr.: Northern portions of northern hemisphere; in North 

 America chiefly in the northeastern portion, breeding in high latitudes 

 and migrating south in winter to the middle Atlantic states and the 

 Great Lakes; accidental in Florida. 



Adult in summer: Top of head, dark gray; back, blackish, the 

 feathers edged with grayish white; rump and upper tail coverts, 

 black or brownish black; a small black spot in front of the eye; 

 breast, grayish, having the appearance of being spotted with black, 

 which black spotting also appears on the sides of the body. This 

 is caused by the feathers of the breast being dark at the base, tipped 

 with white, and on the sides of the body the feathers are white with 

 black spots near the tips; axillars, white. 



Adult in winter: Similar, but lacking the black spots on the breast 

 and sides, which are replaced by pale gray; bill, yellowish at base. 



Length, 9.25; wing, 5; tarsus, .92; bill, 1.30. 



This species is a rare straggler in Illinois and Wisconsin. 



Nelson records a specimen taken on the Lake shore near Chicago, 



