NO. 35 ^^-^ MAMMALS — -HOLLISTKK 3 



from St. Mary's Lake, Montana, is clearly referable to M. sihila, 

 which thus rang^es along the eastern Rockies to the United States 

 boundary, 



RANGIFER FORTIDENS, sp. nov. 

 Type from head of Moose Pass branch of the Smoky River, 

 Alberta (north-east of Mount Robson). Cat. no. 1745^35. U. S. 

 National Museum. Adult male, skin and skull. Collected July 29, 

 191 1, by. N. Hollister and C. D. Walcott, Jr. Orig-inal no. 3826. 



Characters. — Largest of the caribou, exceeding in measurements 

 the largest specimens of Rangifer oshorni and R. montanus. Colora- 

 tion very dark, no whitish on underparts of body. Teeth conspicu- 

 ously larger than in other species. Antlers stout and heavily pal- 

 mated ; not so long and slender as in osborni; main beam nearly 

 straight. Females normally without antlers. 



Color of type. — Head blackish-brown ; neck grayish-brown, with a 

 small white throat-mane. Shoulders and body deep brownish-black ; 

 a stripe of the old pelage on belly shows the long faded brown hair 

 of the winter coat ; the new coat coming in here is almost as dark as 

 the back. Legs blackish-brown ; feet broadly white around hoofs. 

 Rump patch small, white ; tail like back above, bordered with white, 

 a continuation of the rump patch. Five topotypes, four younger 

 bulls and one cow, show the new coat, which is replacing the faded 

 winter pelage, to vary from clove brown to clear black . 



Skull and teeth.— Sknll largest in size, general proportions much as 

 in osborni, but larger, more massive, and with rostrum and palate 

 actually and relatively much broader, and nasals proportionally 

 longer. Exceeds the largest skulls of montanus from the Selkirk 

 and Gold Ranges in every measurement. Teeth conspicuously larger 

 than in any other species; each tooth longer and much heavier. 

 Upper premolars and the mandibular teeth especially large. Pos- 

 terior external cusp of pm^ and pm^ separated from remainder of 

 crown-pattern of respective teeth by a deep and broad valley, 

 widening at the exterior edge; the cusp ridge standing almost at 

 right angles with longitudinal axis of tooth, the crown-pattern con- 

 necting with tooth immediately behind rather than pattern of crown 

 of tooth of which it is a part. Compared with corresponding teeth 

 of other caribou this character is very conspicuous. In the last 

 premolars of other species, the posterior external cusp lies close 

 to and parallel with the diagonal ridge connecting the posterior 

 internal cusp with the main outer cusp, from which it is separated 

 by a narrow and shallow sulcus. Incisors of the " woodland " type 



