148 Nelson New Squirrels from Mexico and Central America. 



Distribution. Nuevo Leon and Tamaulipas, Mexico. 



Characters. Size and general appearance much like pale specimens of 

 Sciurus carolinensis fuliginosus; forelegs and tops of fore and bind feet 

 grayish white ; tail bushy, black, washed with white above. 1 upper 

 premolar. 



Color. En-tire upper parts, except upper surface of feet and forelegs, 

 finely grizzled with grayish-white, dark fulvous and black ; the fulvous 

 darkest on crown and rump, but differing slightly in shade on rest of 

 upper surface. Sides of body and thighs somewhat grayer than back ; 

 forelegs to body and fore and hind feet grayish-white, the hairs having 

 black bases and whitish tips; a small indistinct patch of fulvous some 

 times present in middle of gray on upper surface of hind foot. Under 

 surface of body pure white. Eyes surrounded by ring of pale fulvous ; 

 ears like top of head except for a pale, dingy-fulvous patch behind base 

 in some specimens. Tail moderately bushy, washed with white on upper 

 surface with black and dark fulvous showing through ; below a broad 

 median band of dark fulvous grizzled with black and bordered on sides 

 by a narrow band of black ; edged externally with white. 



Cranial characters. The skull of this species is most like that of S. ocu 

 latus, from which it differs in smaller size, slightly stouter rostrum, and 

 larger foramen ovale. 



Measurements. Type specimen : Total length 466 ; tail vertebrae 220 ; 

 hind foot 63. Average of five adults : Total length 475 ; tail vertebrae 

 223.8 ; hind foot 62.6. 



Remarks. The little variation in the series before me appears to be 

 purely individual and is produced by the slightly varying intensity of the 

 fulvous. The series examined consists of winter and spring specimens. 

 Its nearest Mexican relative is S. oculatus, from which it is perfectly dis 

 tinct. In size and color it is most like the form of Sciurus carolwensis, 

 found in northern and eastern Texas, but the grayish white feet and 

 absence of second premolar serve to distinguish it at once. The absence 

 of tho second premolar throws it with S. arizonensis and S. oculatus, from 

 which its much smaller size, the grizzled blackish-fulvous upper surface, 

 and grayish white feet distinguish it. The lack of a second premolar and 

 darker and much finer grizzled dorsal surface distinguish it sharply from 

 S. yucatanensis. 



S. alleni is a w r ell-defined species of the Arid Tropical zone and is re 

 stricted to a portion of the Tamaulipan faunal district. 



I take pleasure in dedicating this species to Dr. J. A. Allen, Curator of 

 Mammals in the American Museum of Natural History, New York. 



Sciurus oculatus tolucae subsp. nov. Toluca Squirrel. 



Type from north slope of Volcano of Toluca, Mexico, Mex. No. 55927, 

 $ ad., U. S. Nat. Mus., Biological Survey Coll. Collected Sept. 8, 1893, 

 by E. W. Nelson and E. A. Goldman. Orig. No. 5419. 



Distribution. Pine and fir forests on north slope of Volcano of Toluca, 

 and thence north on adjacent east slope of mountains in State of Mexico 



