The dress described by Lewis is worn by Lemhi Shoshone, the tribe that Sacagawea was born into, circa 1788.
Cpt. Lewis, August 20, 1805--the robe woarn by the Sho-sho-nees is the same in both sexes and is loosly thrown about their shoulders, and the sides at pleasure either hanging loose or drawn together with the hands; sometimes if the weather is cold they confine it with a girdel arround the waist; they are generally about the size of a 2 1/2 point blanket for grown persons and reach as low as the middle of the leg. this robe forms a garment in the day and constitutes their only covering at night. with these people the robe is formed most commonly of the skins of Antelope, Bighorn, or deer, dressed with the hair on, tho' they prefer the buffaloe when they can procure them. I have also observed some robes among them of beaver, moonox [likely used for woodchuck, but in this case a relative, the yellow-bellied marmot], and small wolves. the summer robers of both sexes are also frequently made of the Elk's skin dressed without the hair. The shirt of the men is really a commodious and decent garment. it [is] roomy and reaches nearly half way the thye, there is no collar, the apperture being sufficiently large to admit the head and is left square at top, or most frequently, both before and behind terminate[s] in the tails of the animals of which they are made and which foald outwards being frequently left entire, or somtimes cut into a fring[e] on the edges and ornimented with the quills of the Porcupine. the sides of the shirt are sewed, deeply fringed, and ornamented in a similar manner from the bottom upwards, within six or eight inches of the sleve from whence it is left open as well as the sleve on it's under side to the elbow nearly. from the elbow the sleve fits the arm tight as low as the wrist and is not ornimented with a fringe as the side and under parts of the sleve are above the elbow. the sholder straps are wide and on them is generally displayed the taste of the manufacterer in a variety of figures wrought with the quills of the porcupine of several colours; beads when they have them are also displayed on this part. the tail of the shirt is left in the form which the fore legs and neck give it with the addition of a slight fringe. the hair is usually left on the tail, & near the hoofs of the animal; part of the hoof is also retained to the skin and is split into a fring by way of ornament. these shirts are generally made of deer's, Antelope's Bighorn's, or Elk's skins dressed without the hair. the Elk skin is less used for this purpose than either of the others. their only thread used on this or any other occasion is the sinews taken from the back and loins of the deer Elk buffaloe &c. their legings are most usually formed of the skins of the Antelope dressed without the hair. in the men they are very long and full each leging being formed of a skin nearly entire. the legs, tail and neck are also left on these, and the tail woarn upwards, and the neck deeply fringed ond ornimented with porcupine qu[i]lls drags or trails on the ground behind the heel. the skin is sewn in such manner as to fit the leg and thye closely; the upper part being left open a sufficient distance to permit the legs of the skin to be dra[w]n underneath a girdle both before and behind, and the wide part of the skin to cover the buttock and lap before in such a manner that the breechcloth is unnecessary. they are much more decent in concealing those parts than any nation on the Missouri the sides of the leginhs are also deeply fringed and ornimented. sometimes this part is ornimented with little fassicles of the hair of an enemy whom they have slain in battle. The tippet of the snake Indians is the most eligant peice if Indian dress I ever saw. the neck or collar of this is formed of a strip of dressed Otter skin with the fur. it is about four or five inches wide and is cut out of the back of the skin the nose and eyes forming on extremity and the tail the other. beginning a little behind the ear of the animal at one edge of this collar and proceeding towards the tail, they attatch from one to two hundred and fifty little roles of Ermin skin formed in the following manner. the skin is first dressed with the fur on it and a narrow strip is cut out of the back of the skin reaching from the nose and imbracing the tail. this is sewed arround a small cord of the silk-grass twisted for the purpose and regularly tapering in such manner as to give it a just proportion to the tail which is to form the lower extremity of the stran[d]. thus arranged they are confined at the upper point in little bundles of two, three, or more as the disign may be to make them more full; these are then attatched to the collars as before mentioned, and to conceal the connection of this part which would otherwise have a course appearance they attatch a broad fringe of the Ermin skin to the collar overlaying that part. little bundles of fine fringe of the same materials is fastened to the extremity of the tails in order to show their black extremities to greater advantage. the center of the otterskin collar is also ornamented with the shells of the perl oister. the collar is confined aro[u]nd the neck and the little roles of Ermin skin about the size of a large quill covers the s[h]olders and body nearly to the waist and has the appearance of a short cloak and is really handsome. these they esteem very highly, and give or dispose of only on important occasions. the ermin whic[h] is known to the traiders of the N.W. by the name of the white weasel is the genuine ermine, and might no doubt be turned to great advantage by those people if they would encourage the Indians to take them. they are no doubt extreemly plenty, and readily taken, from the number of these tippets which I have seen among these people and the great number of skins employed in the construction of each tippet. scarcely any of them have employed less than one hundred of these skins in their formation.