206 OBSERVATIONS ON THE CHANGES OF 



minate mixture of all colours, engaged in incubation and providing for 

 their families. A blue male may be seen mating with a white female, 

 a blue female choosing for her companion a white male. Birds strangely 

 spotted, some with white, others with blue trains sweeping through 

 the air, rising in hundreds ov^er your head, and presenting so many va- 

 riations in plumage, that the young ornithologist is tempted to believe 

 that he has a half dozen new species to describe. In Augusta regular 

 moult commences, and before the old birds leave Carolina, in autumn, 

 they have acquired their blue colour; thus attaining their full plumage 

 in less than two years. 



Ardea rufescens^ Reddish Egret. This Heron, which I have had in 

 a state of domestication, in its changes of plumage, and the period in 

 which these changes are effected (as far as an imperfect experiment 

 was made), seems to partake strongly of the character of the last men- 

 tioned species. 



The various and opposite changes which our species of Grus and 

 Ardea undergo, from the young to the adult state, is striking and won- 

 derful. In all of them there is no perceptible difference in the plu- 

 mage of the sexes of each species, except in the least Bittern (Ardea 

 exilis), where it is very striking. In the Ardea herodias, A. minor, 

 A. Ludoviciana, A. virescens and A. exilis, no very striking mutations 

 take place, from the young to the adult. The Ardea occidenialis 

 (great White Heron of Audubon), A. alba and A. candidissima are 

 white in all stages of growth, and at all seasons. The Grus Americana 

 and Ardea nydicorax are ash or brown, when in the first year of 

 their existence, and then the former becomes white, and the latter 

 greenish black and white ; whilst, on the other hand, the Ardea cseru- 

 lea and Ardea rufescens are white when young, and blue or rufous 

 when in full plumage. 



Plotus anhinga, Black Bellied Darter. I discovered several nests 

 of this rare and singular species in the immediate vicinity of each other, 

 in one of the dark and gloomy morasses of Carolina in June last. No 

 naturalist has heretofore spoken as having seen its nest, except Mr Ab- 

 bot, in his letter to Mr Ord, who describes the eggs as blue, and the 

 nest containing six young and two eggs. I have sometimes thought 

 that my excellent old friend mistook some heron's nest for tliat of this 



