TARBOPHIS FALLAX
Head-Shields.—Rostral nearly as deep as broad, just visible from above. Internasals much shorter than the prefrontals. Frontal very narrow, twice to twice and a half as long as broad, its width in the middle not more than half that of the supraocular, widening in front and extending beyond the supraoculars to join the preoculars, longer than its distance from the end of snout, as long as or a little longer than the parietals. Two loreals. One preocular, the upper portion of which is much enlarged, and encroaches upon the area occupied in other snakes by the prefrontal and the supraocular; two (rarely three) postoculars. Temporals 2 + 3 or 4. Upper labials eight (rarely nine), fourth and fifth (or fifth and sixth) entering the eye. Four or five lower labials in contact with the anterior chin-shields, which are as long as or shorter than the posterior.
Scales with single apical pits, in seventeen or nineteen rows, longitudinally grooved in the adult, less distinctly in the young. Ventral shields 160 to 189; anal divided; subcaudals 68 to 102.
Fig. 30
Coloration.—The young is elegantly marked with dark brown and yellowish-white on a pale brown ground. On the head, the principal dark markings usually are an oblique band on the posterior half of the supraocular shield, and another, or a large spot, on the parietal, sometimes produced backwards, and forming with its fellow a Λ-shaped band, separated from a large occipital blotch by a yellowish space; anterior half of the frontal shield and shields on the snout edged with dark brown; a dark streak, sometimes broken up into small spots, on the temporal region; yellow spots on the pre- and post-oculars; lips brown, with large, yellow, black-edged spots, or yellow with brown spots; chin with three brown longitudinal streaks. Back with a vertebral series of large roundish dark spots or narrow cross-bars; small spots on the sides, these sometimes forming longitudinal series or accompanied by yellowish streaks or dots; these markings often confluent into three longitudinal streaks on the tail. Belly pale brownish, greyish, or reddish, with numerous pale spots, sometimes with a dark brown line on each side. The adult is greyish, reddish-brown, or olive above. Some specimens preserve more or less the markings of the young, and the dark dorsal markings ([Plate XI].) may be edged with yellowish and ocellar in appearance (var. insignitus, Geoffroy); the belly is yellowish, with small dark spots which usually form longitudinal series, and may be confluent into streaks. A variety common in Dalmatia (neumayeri, Fitzinger) is brown or olive above, without spots, sides with a bluish-grey lateral band, the scales on which are edged with black, the belly uniform yellow. Other specimens are brown or reddish, with light edges to the scales on the sides, or with yellowish lateral lines, or dark olive or dark brown above and black on the sides, each scale with a yellowish central spot; in the last-mentioned the second third of the back may be almost entirely black, and the belly dark olive-grey in the middle and yellowish on the sides. Iris brown, with a golden or coppery circle round the pupil.
Size.—This handsome snake grows to a length of 61⁄2 feet. Specimens 5 to 6 feet long are not uncommon.
Distribution.—Mediterranean coast of France and Western Liguria, Spain and Portugal, Sicily, Lampedusa, eastern coast of the Adriatic, Greece and eastern islands of the Mediterranean, Mediterranean coast of Asia and Sinaitic Peninsula, eastwards to the Caucasus and Persia, North Africa from Egypt to Rio de Oro. It is not known to occur above 2,300 feet altitude in Europe.