Capt. Lewis, July 24, 1805--we observed a great number of snakes about the water of a brown uniform colour, some black, and others speckled on the abdomen and striped with black and brownish yellow on the back and sides. the first of these is the largest being about 4 feet long, the second is of that kind mentioned yesterday, and the last is much like the garter snake of our country and about it's size. none of these species are poisonous I examined their teeth and f[o]und them innocent. they all appear to be fond of the water, to which they fly for shelter immediately on being pursued.
Capt. Lewis, March 28, 1806--we saw a great number of snakes on this island; they were about the size and much the form of the common garter snake of the Atlantic coast and like that snake are not poisonous. they have 160 scuta on the abdomen and 71 on the tail. the abdomen near the head, and jaws as high as the eyes, are of bluish white, which as it receedes from the head becomes of a dark brown. the field of the back and sides is black. a narrow stripe of light yellow runs along the center of the back, on each side of this stripe there is a range of small transverse oblong spots of a pale brick red which gradually diminish as they receede from the head and disappear at the commencement of the tail. the puple of the eye is black, with a narrow ring of white bordering it's edge; the ballance of the iris is of a dark yellowish brown.
Capt. Lewis, March 29, 1806--the garter snakes are innumerable & are seen entwined around each other in large bundles of forty or fifty lying about in different directions through the praries.