59 2 Bulletin American Museum of Natural History. [Vol. XIX, 



sometimes uniting to form an indistinct band; tail basally above col- 

 ored like rump, the upper surface with the hairs dark brown basally 

 and tipped with white, the dusky basal portion showing through and 

 giving the whole upper surface of the tail a grizzled white and brown 

 effect; edges and lower surface clear white; posterior border of rump 

 with a heavy fringe or ruff of white. 



' The above is about the average coloration of the series, but quite a 

 number of the specimens have the gray brown of the upper parts 

 paler, with a faint buffy tinge, decidedly apparent on the throat, lower 

 edge of flanks, and whole pectoral region. In such specimens the 

 upper surface of the tail is deep ochraceous, almost to the base of the 

 hairs, the basal third of the hairs being yellowish brown. The fringe 

 bordering the rump is mixed yellow and white, and the light inner 

 surface of the limbs is also more or less suffused with buffy. Between 

 these extremes there is every stage of gradation, which is especially 

 striking in respect to the upper surface of the tail. In only a small 

 portion of the specimens is the upper surface of the tail either dusky 

 gray or yellowish, varying from the former through a faint tinge or 

 mixture of yellow hairs to wholly yellow, deepening in some to orange 

 ochraceous ; nearly two thirds- of the specimens have the dorsal aspect 

 of the tail more or less conspicuously yellow. 



Measurements. An adult male, 1 total length, 1574; head and body, 

 1371; tail vertebrae, 216; ear, from crown, 190, from notch, 160. Five 

 males, mostly middle-aged: Total length, 1460 (12371574); head 

 and body, 1253 (1031-1371); tail vertebras, 221 (215-229); ear from 

 crown, 189 (178-198); ear from notch, 161 (152-168). Seven adult 

 females: Total length, 1294 (1210-1371); head and body, 1081 (1007- 

 1168); tail vertebras, 208 (203-228); ear from crown, 176 (165-185); 

 ear from notch, 157 (146165). 



Skull. The skull is relatively much shorter and broader than in 

 O. virginianus, with very much shorter and broader nasals, and very 

 much smaller antorbital vacuities, but with the lachrymal pit shallow 

 and imperforate, not deep and perforate as in O. couesi. Compared 

 with O. couesi, the antorbital vacuities are nearly one half smaller; the 

 nasals are very much broader and less arched, with their greatest ex- 

 pansion generally at their posterior third instead of at the middle as 

 in O. couesi; the walls of the posterior nares are more extended pos- 

 teriorly and the narial opening is more vertical; the basisphenoid is 

 more cuneate, through its greater expansion posteriorly; the dentition 

 is very much heavier; the antlers bend more sharply outward and the 

 outward curvature is nearer the skull. 



The type skull, of a fine middle-aged, four-pronged buck, measures 



1 The measurements of the type are not recorded in the C9llector's field catalogue. 

 Also the measurements of the hind foot are not available, having been taken from the 

 metatarsal instead of the tarsal joint. 



