This genus, with certain modifications in the above definition, is made to embrace about twenty-five species from South-Western Asia and Sind and North and Central America. One of the species inhabiting Asia extends into a very small part of Europe. 16. CONTIA MODESTA, Martin The Dwarf Snake _Form._--Moderately slender. Head small, quite flat above; snout obtuse, feebly prominent. Length of tail four to five times in the total length. _Head-Shields._--Rostral a little broader than deep, visible from above. Suture between the internasals as long as or a little shorter than that between the prefrontals. Frontal once and a half to once and two-thirds as long as broad, as long as or longer than its distance from the end of the snout, shorter than the parietals, as broad as or a little broader than the supraocular, widely separated from the preocular. Nostril in the middle or upper part of the nasal. Loreal square or longer than deep. One (rarely two) pre- and two (rarely one) postoculars. Temporals 1 + 2; parietal sometimes nearly touching the fifth upper labial. Upper labials seven, third and fourth entering the eye. Four (rarely five) lower labials in contact with the anterior chin-shield; posterior chin-shields smaller than the anterior, and separated from each other by one or two rows of scales. [Illustration: FIG. 29 (after Sordelli)] _Scales_ with a single apical pit, in seventeen rows. Ventral shields 150 to 191; anal divided; subcaudals 53 to 78. _Coloration._--Not unlike that of a young _Zamenis gemonensis_. Greyish-olive above, uniform or each scale lighter in the centre. The greater part of the upper surface of the head behind the snout, together with the nape, black in the young, with a yellow cross-bar or a pair of yellow spots between the eyes, the bar sometimes confluent with the yellow postoculars, and a horseshoe-shaped band of the same colour on the temples and across the occiput (Plate X.); the black of the nape again edged with yellow behind. More or less distinct traces of these markings are preserved in adult specimens. Upper lip yellowish, with black spots or bars on the sutures between the shields. Lower parts uniform white or yellowish. In the var. _semimaculata_, Boettger, from Chios, small dark spots are scattered over the upper parts of the anterior half of the body. _Size._--This snake rarely reaches a length of 19 inches. It is the smallest Colubrid of Europe. _Distribution._--The Caucasus up to about 5,000 feet, Asia Minor, Chios, Cyprus, Syria, Mesopotamia, and North-Western Persia. The northern slope of the Caucasus appears to be the only part of Europe included in its habitat. The British Museum possesses two specimens labelled as from Constantinople, but the presence of this species in European Turkey requires confirmation.