next to be considered. A fourth series of twelve specimens, from the 

 Adirondack region of New York, ranges from 5.20 to 5.08, with an aver- 

 age of 5.40. Only three specimens range above 5.50, while four fall 

 below 5.30. A fifth series of five skulls, from European localities, 

 ranges from 5.50 to 5.70, with an average of 5.58. 



In the Alaskan series, the width ranges from 2.90 to 3,32, averaging 

 3.20; in the Mackenzie Eiver district series, from 2.87 to 3.28, averag- 

 ing 3.02 ; in the "macrwnfs" series, from 2.70 to 3.20, averaging 2.90; in 

 the Adirondack series, the width ranges from 2.'fo to 2.95, averaging 

 2.80; in the European series, from 3.05 to 3.15, averaging 3.08. Hence — 



Average width. 



Alaskan series 



Mackenzie River District series 



" Macrivrus " series 



Adirondack series 



European series 



3. 20, or 0. 535 of length. 

 3. 02, or 0. 521 of length- 

 2. 90, or 0. 504 of length. 

 2. 80, or 0. 518 of length. 

 3. 08, or 0. 552 of length. 



It thus appears that in the American specimens there is not only a 

 well-marked southward decrease in size, but also a decrease in the rela- 

 tive breadth of the skull, through the greater elongation of the facial 

 portion ; also that the relative breadth is quite appreciably greater in 

 the European form, as noticed long since by Professor Baird.* 



While the European Vulpes vulgaris may be considered as subspecifi- 

 cally distinct from the American {Vulpes vulgaris snhsi^.f ulvus), through 

 its wider skull, less pointed and shorter muzzle, harsher and more reddish 

 fur, etc., the dilferent so-called American " species " or " varieties" {ful- 

 vus, '■^ decussatus'\ ^^argentatus^', and ^^ macriirus") do not have the same 

 claim to subspecific recognition. The Foxes of the colder regions, it is true, 

 have a fuller and softer pelage, a greater tendency to melanism, shorter 

 muzzles, and are larger, yet these differences are so inconstant, especially 

 the differences of color, and so insensibly intergrade, that any attempt 

 at their subspecific recognition seems impracticable, the most diverse 

 varieties in color occurring at the same localities and even among indi- 

 viduals of the same litter.f 



*Mam. N. Amer., pp. 126, 130. 



tOn this point see Bulletin Mas. Comp. Zo6l., vol. i, pp. 159, 1^30. 



