A few turn south-west to the Missouri and Mississippi.

The landscapes here remind one more of the middle part of the United States.

The climate is severe in winter but very warm and dry in summer.

In the extreme south, within the basin of the upper Missouri, the "prickly pear" (_Opuntia_) cactus grows in sheltered places, and suggests affinities with distant Colorado and California.
These great plains and river courses of the middle West were, until about fifty years ago, one of the world's great natural parks or zoological gardens.

Large numbers of wapiti deer, of the smaller Virginian deer,[4] and of the prongbuck "antelope"[5] thronged the grassy flats, and elk browsed on the foliage of the thickets along the river banks.