CALIFORNIA STRIPED RACER. Coluber lateralis (Hallowell)

Field characters.—Body long and very slender; tail long, tapering to fine point; scales of back all smooth (without ridges or keels), in 17 rows. General coloration above dark brown; a sharply defined light line along each side the whole length of the body. (See fig. 63b.) Under surface of body plain yellow.

Occurrence.—Common resident in Upper Sonoran Zone where recorded from Pleasant Valley east to Smith Creek, 6 miles east of Coulterville. Lives in chaparral country. Climbs into bushes and often into trees.

The California Striped Racer is a long, slender, smooth-bodied snake remarkable for its speed and for its skill in climbing. Superficially it bears somewhat of a resemblance to a garter snake, but the two differ in several important ways. The racer has fewer scales; these, counted in a transverse or diagonal line across the body, never number more than 17 rows, whereas a garter snake always has more than 17 and may have as many as 21 rows. The racer's scales are all smooth, whereas those of the garter snake are ridged or keeled. Both species have a single stripe along each side of body, but that of the racer involves the third and fourth rows of scales, while that on the garter snake is on the second and third rows. The racer never has a light stripe down the middle of the back, whereas this is a frequent (though not invariable) mark in the garter snake. Finally, the habitats of the two are different. The racer prefers dry chaparral and tree-covered areas, whereas the garter snake usually lives about water or in damp meadows.

All the racers are rapacious snakes, and live more or less upon vertebrates; the present species, at the appropriate season, takes toll of nestling birds. The long slender form of body seems to be a correlative of climbing ability, as 'tree' snakes in all parts of the world are of this general form.

In a dry grassy cañon bottom near Coulterville, May 12, 1919, one of these snakes was come upon while it was on the ground; its body rested in a long U-shape and its head was slightly raised. The snake was perfectly motionless, not even running its tongue out and in, as would a garter or gopher snake under similar circumstances. The snake was watched for a minute or more and a photograph was taken. During this time it could not be seen that the animal had moved at all. Then one of the observers changed position and advanced slightly in the direction of the snake, whereupon the latter abruptly vanished down a small hole in the ground, previously unnoticed by us.

While at work in camp at Pleasant Valley on the afternoon of May 27, 1915, our attention was attracted by a disturbance among some Western Chipping Sparrows and Green-backed Goldfinches in the top of a small blue oak. The cause for excitement was found to be a California Striped Racer about 10 feet above the ground in the oak. The snake was at the site of a nest and apparently just about to seize a young bird. The snake was shot by one of our party and then removed from the tree, but the excited birds did not cease their loud chippings for some time afterward.

Among some scattered manzanita bushes on a hillside near the McCarthy ranch, a California Striped Racer was found on June 5, 1915, while it was raiding the brood of a pair of Black-throated Gray Warblers. The snake appeared to have already swallowed one of the nestlings, and another lay on the ground. The female parent was flying about distractedly, uttering notes of concern. At our approach the snake attempted to make off into the brush but was shot.