﻿Field and Forest 



A MONTHLY JOURNAL 



DEVOTED TO THE NATURAL SCIENCES. 



Vol. II.— SEPTEMBER, 1876.— No* 3. 



"Sexual, Individual and Geographical Variation" 

 in the Genus Leucosticte. 



In the Bulletin of the Geological and Geographical Survey of the 

 Territories, No. 2, (May 11, 1875,) I published a " Monograph of the 

 Genus Leucosticte, or Gray-crowned Purple Finches," based on more 

 than four hundred specimens, which had been brought together for 

 that especial purpose, a larger number by at least three hundred than 

 any author had previousiy been able to examine at one time, these 

 birds having been among the very rarest in the North American Avi- 

 fauna. This series embodied the material requisite for a comprehen- 

 sive study of the subject, which was found to be fully illustrated in the 

 special points of " sexual, individual and geographical variation," 

 rendering of easy definition the forms represented. Many of the de- 

 ductions, under these several heads, however, are questioned by Mr. 

 J. A. Allen, in a paper entitled " Sexual, Individual and Geographical 

 Variation in Leucosticte tephrocotis." 1 [Bulletin of the Geological 

 and Geographical Survey of the Territories, Vol. II, No. 4, pp. 345- 

 350. Washington: Government Printing Office, July 1, 1876.] 



" Some very positive remarks " regarding sexual differences in par- 



1 Under this name Mr. Allen would include, as expressions of climatic or individual 

 variation, all the forms which are usually recognized as distinct species, or, at least, 

 " geographical races," — five in number — certain assumed " laws " of climatic varia- 

 tion being cited to explain the differentiation of the forms in question to supposed 

 varietal rank. It has been clearly demonstrated, however, [see pages 58 and 59 of< 

 my monograph]- that instead of in any way confirming this theory, the facts prove 

 the case of this genus to be a notable exception to the " laws " which it is endeavored 

 thus to bring into requisition. Taking as the only available, and, withal very reason- 



