The range of this genus, embracing eight species, extends from South-Eastern Europe and Africa north of the equator to Central Asia and India.
2. Eryx jaculus, Linnæus
The Javelin Sand-Boa
Form.—Stout. Head small, not distinct from neck; snout projecting beyond the mouth; eye directed upwards and outwards; a feeble mental groove. Tail, ending very obtusely, one-tenth to one-sixteenth of the total length. Anal spurs more or less developed, often absent in the female.
Head-Shields.—Rostral very large and broad, with angular horizontal edge, followed by a pair of internasals and a second row of two or three small shields, the rest of the upper surface of the head covered with scale-like shields, 5 to 8 from eye to eye across the vertex, 7 to 11 round the eye; 9 to 12 upper labials, second or third deepest, separated from the eye by one or two series of scales. Nostril between the internasal and two nasals, the anterior of which sometimes fuses with the former. Two or three series of scales between the nasals and the eye.
Fig. 15 (after Sordelli)
Scales.—Smooth, feebly keeled on the posterior part of the body and on the tail, in 40 to 51 rows. Ventrals narrow, occupying about one-third of the ventral surface, 163 to 200; anal small, entire; subcaudals all or greater part single, 15 to 29.
Coloration.—Pale greyish, reddish, or yellowish-brown above, with brown, purplish-brown, or blackish markings, which may be very irregular or form a single or alternating series of large blotches or cross-bands on the back; the sides with smaller spots; these markings may be confluent and so large as to reduce the ground colour to small yellowish spots; one, two, or three short, dark stripes often present on the nape; a dark streak from the eye to the angle of the mouth; sometimes a dark curved band from eye to eye across the upper surface of the snout. Lower parts yellowish-white, uniform or with small blackish spots.
Size.—21⁄4 feet is the greatest length which this snake is known to attain.