96 BULLETIN 135, UNITED STATES NATIONAL MUSEUM 



nest, the surrounding branches and the ground under it, were pro- 

 fusely whitewashed with the excrement of the young, as is generally 

 the case with all of the herons. 



The other nest illustrated the last chapter in the development of 

 the young, which were nearly ready to fly. It was 20 feet above 

 the water on the outer end of a leaning red mangrove and the two 

 large white birds in it could be plainly seen from the ground; when 

 I climbed the tree one of them stood up in the nest and posed grace- 

 fully for his picture. They were practically fully grown and fully 

 feathered, pure white all over and lacking only the crest plumes and 

 the plumelike feathers on the back of adult birds, which I believe 

 are not acquired until the second nuptial season. 



On March 27, 1908, I found, on Clive Key, in this same region, a 

 nest of the great white heron placed within 3 feet of the ground on 

 a low branch of a black mangrove near the center of the island; it 

 contained three small youngcovered with white down. I was informed 

 by the resident plume hunters that the great white herons raise two 

 broods each season, one in January and one in April, but I am more 

 inclined to think that the breeding season is prolonged over a period 

 of fom* or five months and that only one brood is raised by each 

 pail'. We found a number of empty nests that showed signs of recent 

 occupancy and saw plenty of immature birds on the wing in March. 

 Ernest G. Holt found young birds as large as adults and nearly ready 

 to fly on December 28, 1923; these eggs must have been laid in 

 October. 



Eggs. — The eggs of the great white heron are not readily distinguish- 

 able from those of the Ward heron in size or color; they are of the 

 usual heron's egg color, pale bluish green, or "pale olivine." The 

 measurements of 40 eggs average 61.1 by 42.4 millimeters; the eggs 

 showing the four extremes measure 71 by 47, 66.5 by 48.8, 51.7 by 

 35.5, and 52.7 by 34.2 millimeters. 



Plumages. — The young great white heron is clothed like the young 

 great blue heron, except that its down and plumage is wholly white 

 at all ages. The sequence of plumages and molts is also the same 

 in both species. The plumage of the head, neck and body is acquired 

 in about that order; these parts are fully feathered by the time the 

 bird is two-thirds grown and before the wings are fully developed. 

 Young birds remain in the nest until full}^ grown and by this time 

 the wings are complete. The juvenal plumage, which is entirely 

 devoid of plumes on the head, breast, and back is worn for about a 

 year. During the second fall, when the young bird is over a year 

 old, a plumage is apparently assumed which is much like the adults 

 at that season; but the fully adult plumage is probably not acquired 

 until the following spring or fall, at 2 years of age, or later. Adults 

 have a complete molt in summer and fall and a partial molt, which 



