Mammals 27 



macrodon (Twin Lakes) and U. shoshone (Estes Park). Of these 

 four large bears, bairdi is considerably the largest, the basal 

 length of the skull in old males being 348 mm., whereas in the 

 others it is 320 or less. U. macrodon, a species of the higher 

 mountains, is described by Merriam as "peculiar for a grizzly, 

 resembling some of the Alaska brown bears; general body color 

 rich brown, almost reddish brown, darker on hump and lightly 

 washed with pale tipped hairs on upper part of back, head rather 

 uniform brown." The basal length of an old male skull was 

 312 mm., thus a little smaller than planiceps or shoshone. U. 

 planiceps and U. shoshone are known from skulls alone. The 

 former was based on a skull collected by Dr. F. V. Hayden, per- 

 haps in the foothills or along the western edge of the plains. 

 Compared with U. macrodon, the zygomata of planiceps are very 

 much more broadly outstanding and outbowed, and the molar 

 teeth are decidedly smaller. U. shoshone is placed in a different 

 group, with the skull rather high instead of flattened; it extends 

 north into Wyoming. The interorbital breadth of these various 

 bears (old males) is 72 mm. in macrodon, 75 in planiceps, 78 in 

 shoshone and 81 in bairdi. 



It would appear from the above that Colorado is (or was) 

 plentifully supplied with bears, but it is not impossible that 

 others will be detected. There are five kinds known from Wyo- 

 ming, two from New Mexico, two from Arizona, and one each 

 from Utah and Texas, not yet reported from Colorado. The 

 number of available skulls has not been great enough to settle 

 all the problems presented by these bears, so every additional 

 specimen will be of great value and interest. Unfortunately 

 Dr. Merriam does not figure any of the four Colorado species 

 in his revision. 



The family Procyonidae is represented by the raccoon, 

 Procyon lotor of Linnaeus. In Turton's edition of the Systema 

 Naturae (1806) we are informed that it "inhabits northern parts 

 of America, in hollow trees; eats eggs and shell fish; washes its 

 food, and carries it to its mouth with the fore-paws; sense of 

 smell and touch exquisite; memory tenacious; sleeps from 12 at 

 night till 12 in the day; climbs easily; fearful of hog's bristles; 

 brings 2-3 young." Warren notes that it is very fond of corn 

 when it is in milk, and in California raccoons have been known 



