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



General plumage, white; the wings and tail, more or less black; 

 head and upper neck, bare in adult, feathered in immature birds. 



Mycteria americana. 

 Wood Ibis. 



See No. 78. 



Suborder HERODII. 

 HERONS, EGRETS, BITTERNS, ETC. 



Family ARDEID^. Herons and Bitterns. 



Special Characters: In the true Herons there are three pairs of 

 thick tracts of concealed feathers known as powder down tracts, 

 one on the lower back, one on the belly, and one on the breast. The 

 Bitterns lack the down patch on the breast, having only two. Bill, 

 straight, stout, and sharp pointed, having a groove on the side of the 

 upper mandible; lores, with bare space variable in size; tail, short, 

 usually 12 feathers in the Herons and 10 in the Bitterns; hind toe, 

 on level with the front ones ; inner side of middle toe nail, with distinct 

 comb-like edge. 



Tail feathers, 10; two pairs of powder down tracts (concealed 

 feathers ) . Subfamily Botaurince. 



Bitterns. 



Tail feathers (usually), 12; three pairs of powder down tracts. 



Subfamily Ardeinoe. 

 Herons. 



* GROUP 1. Wing, less than 6 inches long. 



Least Bittern. 



