Capt. Lewis, May 17, 1805 --..Capt. Clark narrowly escaped being bitten by a rattlesnake in the course of his walk, the party killed one this evening at our encampment, which he informed me was similar to that he had seen ; this snake is smaller than those common to the middle Atlantic States, being about 2 feet 6 inches long; it is of a yellowish brown colour on the back and sides, variagated with one row of oval spots of a dark brown colour lying transversely over the back from the neck to the tail, and two other rows of small circular spots of the same colour which garnis the sides along the edge of the scuta. it's bely contains 176 [s]cuta on the belly and 17 on the tale..
Capt. Clark, May 17, 1805-- ..I was nearly treading on a small fierce rattle snake different from any I had ever seen &.one man [of] the party killed another of the same kind..
Capt. Lewis, June 15, 1805 --..when I awoke from my sleep today I found a large rattlesnake coiled on the leaning trunk of a tree under the shade of which I had been lying at the distance of about ten feet from him. I killed the snake and found that he had 176 scuta on the abdomen and 17 half formed scuta on the tale ; it was of the same kinde which I had frequently seen before ; they do not differ in their colours from the rattle-snake common to the middle atlantic states, but considerably in the form and figures of those colours..