MAMMALS OF MINNESOTA. 265 
is no perceptible ridge outside the hollow. This feature is 
- doubtless due to the pawing of buffaloes in former years while 
rubbing upon the boulders, the dust loosened in this manner be- 
ing blown away by the winds. Mr. Pierre Bottineau, a very ex- 
perienced and observing voyageur and guide, still living at Red 
Lake Falls, attributes the polished surface of such projecting 
boulders, and of the ledges of rockin Pipestone and Rock coun- 
ties to rasping by the hair and horns of buffaloes in this way; 
which seems more probable, than that this polishing was 
done by wind-blown particles of sand and dust. (See Geol. Nat. 
Hist. Surv. Minn., vol.*i, pp. 68, 66 and 541; 1884). Catlin’s 
descriptions make it certain that the polished rock-surfaces in 
the vicinity of the Pipestone quarry were much more noticeable 
in his time thannow.” Similar observations and explanations are 
recorded by Dr. George M. Dawson in the region of the Bow 
and Belly rivers east of the Rocky mountains in British America, 
where he states that ‘‘all the larger boulders of the district are 
surrounded by a shallow saucerlike depression, caused by the 
pawing of the buffalo, and their angles are worn quite smooth 
and glossy by the rubbing of these animals uponthem.” (Rep. 
Prog. Geol. Surv. Canada, 1882-84, p. 149c.) 
Mr. Upham also writes, ‘‘ another notable feature ascribed 
to buffaloes is the very rough surface often found on areas of 
slightly moist land in the Red river valley, the ground being 
indented by many hollows and holes five to twenty feet across, 
and one to five feet deep, with steep sides. These are com- 
monly called ‘buffalo-wallows’.” This propensity to wallow 
and roll in the mire reminds one of the buffalo proper of warm 
regions, and is not found in the animals of the genus Bos. 
Allen says, ‘‘their especial delight is to roll in the mud, or in 
‘wallowing’ as it is called, from which exercise they arise 
looking more like an animated mass of mud than their former 
selves. The object of these peculiar ablutions is doubtless to 
cool their heated bodies and to free themselves from trouble- 
some insects. When not finding a muddy pool ready at hand, 
an old bull proceeds to prepare one. Finding in the low parts 
of the prairies, says Catlin, a little stagnant water amongst the 
grass, and the ground underneath soft and saturated with 
moisture, an old bull lowers himself upon one knee, plunges 
his horns into the ground, throwing up the earth and soon 
making an excavation into which the water trickles, forming 
for him in a short time a cool and comfortable bath, in which 
he wallows ‘like a hog in the mire.’ In this ‘delectable lava’ 
Alif( 
