Note 163 — {122} CHAPTER VII
Reading edition
Coluber obsoletus, Say.—Body black above, beneath whitish, with large subquadrate black spots, which are confluent, and pale bluish towards the tail; throat and neck pure white; sides between the scales with red marks.
Description. Body black, anterior half with a series of continuous, dilated dull-red large circles, formed upon the skin between the scales, on the side; on many of the scales, are white marginal dashes near their bases: these scales are placed in groups each side of the vertebræ of the anterior moiety of the body; scales bipunctured at tip; beneath flat, so as to produce an angle or carnia each side; white slightly tinged with yellowish red, irrorate with black points, and spotted with large oblong quadrate marks, which gradually become more continuous, confluent and plumbeous towards the tail, occupying nearly the whole surface; head beneath and throat pure white; posterior canthus of the eye two-scaled; iris blackish; pupil deep-blued black, enclosed by a silvery line.
One specimen, Pl. 228 — Sc. 67 ?
Another specimen Pl. 233 — Sc. 84
Another specimen Pl. 228 — Sc. 84
Total length — 4 feet 115⁄8 inches.
Tail length 4 feet 101⁄8 inches.
The lateral red marks are not perceptible, unless the skin be dilated so as to separate the scales; and the small white marginal lines on the bases of some of the scales are observable only on close inspection. It varies in being nearly or quite destitute of spots on the anterior portion of the body beneath, but the posterior half of the inferior surface still remains blackish. The whole animal bears strong resemblance to C. constrictor; but the scales are decidedly smaller, and the number of its plates and scales approach it still more closely to that uncertain species C. ovivorus. It is not an uncommon species on the Missouri from the vicinity of Isle au Vache to Council Bluff.
Penis terminated by a hemisphere, covered with compressed, white spines, which are reflected at tip; the series interrupted on the posterior side of the member by a canal; it is much dilated, dark reddish brown, abruptly contracted at base from the exterior side, and with a prominent tubercle on the middle of the inner side: length one inch and a quarter, width about seven-sixteenths of an inch.—James.