98 



NORTH AMERICAN BIRDS EGGS. 



upon which the three to six eggs are laid. They are a pale greenish blue in 

 color, and measure 1.45 x 1.10. Data. Avery's Island, Louisiana, April 10, 

 1894. 5 eggs on a platform of twigs placed in a willow trea growing on the edge 

 of a pond. Collected by E. A. Mcllhenny. 



20 1 a. Frazar Green Heron. Butorides virescens frazari. 



A darker variety found in Lower California; nesting the same as the common 

 species. 



20 1 b. Anthony Green Heron. Butorides virescens anthonyi. 



A lighter, desert form found in the arid portions of the interior of southwest- 

 ern United States and Mexico. 



NEST AND EGGS OF GREEN HERON. 



202. Black-crowned Night Heron. Nycticorax nycticorax nsevius. 



Range. North America from southern British Provinces, southward; winters 

 along the Gulf coast and beyond. 



A well known bird, often called "quawk" from the sound of its notefrequent- 

 ly heard in the evening. While, in some localities, only a few pairs of these 

 birds are found nesting together, most of them gather together into large colo- 

 nies during the breeding season. In New England they generally select a re- 

 mote pine grove as their breeding grounds. If not disturbed they will return 

 to this same place each year. Their nests are built of sticks and lined with 

 small twigs, and are placed well up towards the tops of the trees. 



