354: MONOGRAPHS OF NORTB AMERICAN RODENTIA. 



hut refer to one specimen as having the margin of the car hrown. These 

 and other slight discrepancies arc noted by Baird, who, in 1857, doubtfully 

 referred the Lepus texianus of Waterhouse to L. callotis, bul left the L. texi- 

 (iiius of Audubon and Bachman in his list of those his material did not allow 

 him to satisfactorily discuss. 



It will be noticed that in the descriptions accompanying the above-cited 

 names the black spot at the tip of the ear, which is so constant in specimens 

 from the United States, is not mentioned except in Waterhouse's description 

 of his "Lcpus texianus!", and that the other features of coloration apply 

 strictly to the Mexican specimens, and in less degree to those from Texas, 

 but not at all to specimens from the Territories of Arizona, Nevada, Utah, 

 Oregon, and Wyoming. Professor Baird very distinctly referred to the differ- 

 ences presented by specimens from the northward as compared with those 

 from Texas and Mexico, and thought it possible the form from the more 

 northern localities in the United States might prove to be a distinct species, 

 at the same time calling attention to the complete gradation by easy stages 

 from the one extreme to the other. Although this gradation is unquestionable 

 the constancy of the very considerable differences between the northern and 

 southern forms seems to warrant their differentiation as geographical races. 

 Waterhouse's description clearly refers to the northern type, which he 

 describes as having the fur "long and soft, the general hue of the animal 

 pale, inclining to ashy-gray, but strongly mottled with black and brownish- 

 white", "the ears with a large black patch at the apex externally", etc., and 

 hence his name, notwithstanding its unfortunate geographical allusion, is 

 unquestionably applicable to the northern type, while Texas specimens, espe- 

 cially those from near the Mexican border, present an intermediate phase 

 more strongly resembling the southern than the northern type. 



Lepus callotis finds its nearest ally in L. californicus, but differs from it 

 so considerably in color and in other respects (as will be pointed out under 

 the head of L. californicus) as to be readily distinguishable from it. From 

 L. campestris, which agrees with it quite nearly in size, and also resembles 

 it considerably in color, it is easily separable, as already shown in the discus- 

 sion of that species ; L. campestris differing from L. callotis in its shorter ears, 

 in wanting the black on the tail, and in becoming white in winter. 



Geographical distribution. — The habitat of Lepus callotis var. texianus 

 may be given as extending from Southeastern Oregon southward to Mexico, 

 and from the Sierra Nevada Mountains eastward to near the eastern border 



