In a recent post, we talked about fur hats, and one of the references called out wolf fur being used.
A reply to that suggested that "wolf" may mean "coyote" fur.

Here are some references about coyotes, or wolves. The word coyote, doesn't appear in any of the original journals that I have read through. The oldest source that uses the word is Ruxton, who wrote in 1848 and 1851.
The older sources refer to them as prairie or medicine wolves.

From Ruxton:

Passing a large plain, in the midst of which stood a lone poplar, wolves were continually crossing
the road, both the coyote and the large grey variety

I one day killed an old buck which was so poor that I left the carcase on the ground untouched.
Six coyotes, or small prairie wolves, were my attendants that day, and of course, before I had left
the deer twenty paces, had commenced their work of destruction

Besides the buffalo wolf, there
are four distinct varieties common to the plains, and all more or less attendant upon the buffalo.
These are, the black, the [Pg 90]gray, the brown, and last and least the coyote, or cayeute of the
mountaineers, the “wach-unka-mănet,” or “medicine wolf ” of the Indians, who hold the latter
animal in reverential awe. This little wolf, whose fur is of great thickness and beauty, is of diminutive
size, but wonderfully sagacious, making up by cunning what it wants in physical strength.

From Russell:

THE WOLF
Of this Species of animals there are several kinds as the Buffaloe Wolf the Big Prarie Wolf and
the small prarie or Medicine Wolf. The Buffaloe wolf is from 2 to 3 ft high and from 4 to 5 ft long
from the tip of the nose to the insertion of the tail its hair is long coarse and shaggy Its color
varies from a dark gray to a snowy whiteness. They are not ferocious towards man and will run
at sight of him. The big Prarie wolf is 2 ft high and 3 1/2 ft long; its hair is long and shaggy: its
color is a dirty grey often inclining to a brown or brindle. The least kind is little Prarie or Medicine
Wolf: its size is somewhat larger than the red fox: its color is brownish grey and its species
something between the Big Wolf and the Fox. The Indians are very superstitious about this animal
when it comes near a Village and barks they say there is people near Some pretend to distinguish
between its warning the approach of friends and enemies and in the latter case I have often seen
them secure their horses and prepare themselves to fight. I have often seen this prophecy tolerably
accurately fulfilled and again I have as often seen it fail but a supperstitious Indian will always
account for the failure The habits of these three kinds of wolves are similar Their rutting season is
in March, the female brings forth from 2 to 6 at a birth

Approaching the Buffalo Under the Disguise of a Wolf, Alfred Jacob Miller