1 6 Chapman, The Standing of Ardetta neoxena. \ Un 



While I do not pretend to explain this unusual degree of varia- 

 tion, I can see no reason for making it the basis of a theory 

 that neoxena is a color-phase of exilis. Only three of the fourteen 

 known specimens depart widely from what is evidently the type 

 of coloration, and in every instance these differences are clue 

 to albinism or melanism, not one of the specimens showing 

 any approach to exilis. Nor do the known cases of dichromatism 

 among Herons give us any ground for asserting that neoxena is 

 a dichromatic phase of exilis. Aside from the important differ- 

 ences exhibited by the young and female, a careful compari- 

 son of the adult males shows no substitution of colors such as 

 we find in the phases of Ardea rufescens, Megascops, Fulmarus, or 

 even Stercorarius. This is especially marked in the under parts, 

 which in exilis are essentially all buffy, while neoxena has a chest- 

 nut forneck, a chestnut and black belly, and, in every instance, jet 

 black under tail-coverts. 



It is natural that the variability of neoxena should cause us to 

 regard it with suspicion, but beyond the fact that the two birds 

 are generically related and of the same size, there is not one 

 grain of evidence implicating exilis. This latter bird is repre- 

 sented in our collections by hundreds of specimens not one 

 of which has given reason for believing the species is dichromatic. 



For the loan of specimens of this rare bird I desire to heartily 

 thank Messrs. William Brewster, J. H. Ames, Charles B. Cory, 

 J. H. Fleming, Jas. R. Thurston, and L. W. Watkins. 



BIBLIOGRAPHY. 



1SS6. Cory, Charles B. Description of a New North American Species 



of Ardetta. Auk, III, 2(12. 

 1SS6. Cory, Charles B. More news of Ardetta neoxena. Auk, III, 40S. 

 Gives collector's name and approximate place of capture of the 

 tvpe specimen. 

 1886. Coues, Elliott. Key to North American Birds. Third Edition. 

 Appendix, 888. 



Description of Ardetta neoxena. 

 1SS9. Ridgway, Robert. Manual of North American Birds, 127. 

 Description of Botaurus neoxenus. 



