° 1915 J Bangs, Dichromatic Herons and Hawks. 48o 



dish Egret of America, Dichromanassa rufescens (Gml.) whose white 

 phase has been named D. pealei (Bp.). In some places, especially 

 in some of the Bahamas, this species presents a mixed plumage, 

 partly white and partly blue, called by Maynard Ardea ruja mutata. 

 The Reef Heron, Dcmigretta sacra (Gml.) of the coasts and islands 

 of the Indian and Pacific Oceans; and the Little Blue Heron, 

 Florida ccerulea (Linn.). In this latter species the white dress is 

 usually a sign of immaturity, and is changed, for a blue one as the 

 bird becomes fully adult. But this is not always the case. I have 

 myself seen birds breeding in the white plumage, and fancy that 

 such individuals retain the white dress throughout life. 



Albinism, melanism and erythrism are of course but manifes- 

 tations of an abnormal condition of pigmentation, and as such are 

 directly inherited. Thus, miscolored forms of this kind may appear 

 to have geographic limitations, similar to those of real subspecies. 



All these facts being perfectly well known, and all other Herons 

 showing dichromatism having been finally treated as such by orni- 

 thologists, it seems to me extraordinary that the Great White Heron 

 of Florida should still be dealt with as though it were a species. 



There is an accumulation of evidence now, both printed and on 

 the labels of museum specimens, to show that Ardea occidentalis 

 Aud. and Ardea herodias ivardi Ridg. breed together freely. We 

 also have an intermediate form in Ardea wurdemanni Baird, that 

 is very variable, sometimes shading toward the blue phase, some- 

 times toward the white phase. All three are of exactly the same 

 size and proportions, and show no specific characters except color, 

 which I consider has no real significance in such a case. 



In Cuba and the Isle of Pines a Great White Heron also occurs, 

 associated with birds in normal plumage, — Ardea rcpens Bangs and 

 Zappey. This form can be separated from the Great White Heron 

 of Florida b} r its lesser dimensions. In size and proportions it 

 exactly agrees with the Great Blue Heron of the West Indies, the 

 white phase of which I unhesitatingly pronounce it to be. 



I should therefore propose to change the standing of some of the 

 American Herons as follows — 



Ixobrychus neoxenus (Cory) must become a synonym of 



IXOBRYCHUS EXILIS (Gml.). 



