CHAPTER IX. 
BIG-HORN AND ROCKY MOUNTAIN SHEEP. 
Tue big-horn and Rocky Mountain sheep are to the Con- 
tinent of North America what the ibex and chamois are to 
Europe. However, there is no great similarity of appear- 
ance between these representatives of the Eastern and West- 
ern world, although the differences are no greater than 
can be found between races of sheep and goats. From 
what I have said, the reader will be prepared to learn that 
both these interesting animals are inhabitants of mountain 
districts, searching for their food and enjoying their gam- 
bols upon the verge of the precipitous sierras, where mor- 
tals’ tread dare not touch, where the slightest false step, 
the slightest hesitation, would hurl them down to inevita- 
ble destruction. 
The elevation of the situations they select for their rest- 
ing-places is doubtless governed by temperature: thus they 
ascend to greater altitudes in summer than in winter; at 
the sume time, if compelled through alarm, they will un- 
hesitatingly retire into regions covered with perpetual 
snow, and nature seems to have so well provided for such 
occasions that they appear to do so without suffering in- 
convenience. From my own experience, I have formed the 
conclusion that both the above animals are partially noc- 
turnal; by this I do not wish it to be understood that they 
wander about when it is impenetrably dark, but that when 
starlight or moonlight occurs, they avail themselves of its 
use to descend from their mountain fastnesses into the 
valleys beneath in search of favorite food, a performance 
