I40 A MONOGRAPH OF THE PHEASANTS 



Several birds have been shot in the native state of Chamba, in the western 

 Himalayas, with no trace of white upon the back. It was then discovered that the 

 description which Latham gave of this pheasant made no mention of the white back, nor 

 was it shown in his coloured plate. Thereupon by a process of logic, sound as far as it 

 went, the old name of impeyanus was stripped from the common white-backed bird and 

 replaced by refulgens. Then ensued a long argument, consuming much valuable 

 printers' ink and paper, pro and con ; whether the chance of Latham's having secured 

 by accident a specimen of the rare Chamba bird, outweighed the possibility of his having 

 erred in observation. I have found two solutions, both adequate : first, Latham himself 

 settles the dispute beyond doubt ; and second, the Chamba bird is nothing but a chance 

 variation or mutation, of no significance from a taxonomic standpoint. 



As to the first point, under the caption of Early History I have quoted the account 

 of the Impeyan Pheasant from Latham's General History, published thirty-six years 

 after his first contribution. Here he gives us the additional information that, " In the 

 drawings of Lord Mountnorris is one of the male, with a large patch of white in the 

 middle of the back, which I have not seen in any other representation of this singularly 

 beautiful species." So there appears little room for doubt that Latham did have a black- 

 backed specimen, if, indeed, he had more than the various sketches which he mentions. 



Now, as to the evidence that the black-backed bird, alias chambanus, alias 

 impeyanus, is no more than a variation, and without standing as a species. The white 

 back in normal adult males presents one of the most variable characters of the plumage, 

 not only in absolute purity or relative abundance of metallic markings, but in actual 

 area. In only six specimens, selected at random from thirty or more, the length of the 

 white patch varies antero-posteriorly from 95 to 155 mm. ; while the distance from the 

 posterior edge of the white zone to the tip of the longest tail-coverts may be as little as 

 63 or as great as 120 mm. 



The occasional occurrence of albinism in adult male Impeyans, both partial, 

 symmetrical and rarely complete, while it may have no direct bearing on the problem 

 under discussion, should be mentioned. 



Coming now to the actual black-backed birds themselves, examination of all the 

 known specimens shows as great variability inter se, as the difference between them and 

 normal male impeyanus. This will be evident from the following tabulation of the 

 characters supposed to be diagnostic of the black-backed birds — 



'* Underparts entirely glossed with metallic golden green." 

 This gloss may be {a) typically like the above description ; 



(p) confined to the breast and irregularly down one side ; 



{c) confined to the throat and upper breast. 

 " Upper tail-coverts chestnut, tipped with golden green." 



(a) typically like above description ; 



[b) an excess of green, with a little basal rufous ; 

 if) as in normal impeyanus. 



" Lower back golden green." 



This whole area impresses one as abnormal, as the metallic 

 tips are so very small that they are completely separated and 



