372 FIELD MUSEUM OF NATURAL HISTORY ZOOLOGY, VOL. IX. 



Length, 16 inches; wing, 6.50; tail, 2.40; tarsus, 1.85; bill, 2.30. 



The Green Heron is a common summer resident in Illinois and Wis- 

 consin and breeds throughout both states in suitable localities. 

 Nidification commences in May. The nest is a mass of small twigs 

 placed in a bush or low tree near water. The eggs are 4 to 6, pale 

 blue or greenish blue, and measure 1.50 x 1.15 inches. An admirable 

 article on the breeding of this species in Wisconsin is given by Mrs. 

 Irene G. Wheelock in The Auk, Vol. XXIII, 1906, p. 432, to which 

 those interested are referred. 



Genus NYCTICORAX Forster. 

 88. Nycticorax nycticorax naevius (Booo.). 

 BLACK-CROWNED NIGHT HERON. 



Local name: Quawk. 



Distr.: Whole of America, from Ontario and Manitoba south to 

 the West Indies and South America to the Falkland Islands. 



Adult: Crown, head, back, and scapulars, greenish black; fore- 

 head, lores, most of the neck and under parts, white or ashy white; 

 wings and tail, gray; legs and feet, yellow; two or three very long 

 occipital plumes, white in the breeding season. 



Adult. 



Black-crowned Night Heron. 



Immature. 



