Horned Rattlesnake

Crotalus cerastes, (Hallowell)

Colouration: Pale brown, yellow, or pinkish, with a series of dull blotches, generally separated by white interspaces. On the sides are irregular rows of small black or brown spots. Most specimens have several black bars on the tail.
Dimensions: The maximum length is about thirty inches. Following are the measurements of a rather small specimen, from the Colorado Desert:
Distribution: Desert areas of Arizona, southern Nevada, southwestern Utah and eastern California.
Habits: In its methods of progression this very interesting snake differs from every other North American serpent. The remarkable fashion in which it loops its way over the desert sands is an exact reproduction of the motions displayed by the several species of vipers that inhabit the borders of the African and Arabian deserts.

While this is one of the smallest species of Crotalus, it is the most distinct, owing to the horn-like process over each eye, which is really an elongation of the upper eye-shield (supraocular). The body is stout, with strongly keeled scales--the three central rows of scales having highly-raised keels, of tubercular formation.

Total Length . . . . . 17 1/2 inches.

Tail, exclusive of rattle . . . . . 1 1/2 inches.

Greatest Diameter . . . . . 3/4 inches.

Width of Head . . . . . 3/4 inches.

Length of Head . . . . . 13/16 inches.

Number of segments of rattle, five, including the original "button"--each of the segments successively larger, denoting a steadily increasing growth.

When progressing in a very leisurely manner the Horned Rattlesnake glides almost in a straight line, as do all Rattlesnakes--very slowly, with head slightly raised and horizontal. It is when the creature quickens its gait that the movements become complicated and altogether unlike those of a serpent. The progression is by a series of large loops of the body thrown forward; one loop follows another with perfect symmetry of alternation, while the snake moves off at a sharply oblique angle to the direction in which the head is pointing and with such a degree of agility that the spectacle is not only grotesque, but bewildering. It in no way resembles a crawl; it is a walking movement.

Here we see Nature's admirable provision to enable a heavy-bodied snake to progress at some speed over desert sands. That this is the only fashion in which a thick-bodied snake could display agility on soft soil is well illustrated by the fact that these singular movements have been adopted by the vipers of the African deserts and again, far removed from them, by our one species of rattlesnake that inhabits the desert proper.