_Head-Shields._--Rostral broader than deep, just visible from above. Internasals shorter than the prefrontals. Frontal much broader than the supraocular, once and one-fourth to once and a half as long as broad, as long as its distance from the end of the snout, shorter than the parietals. Nasal divided or semidivided. Loreal twice and a half to thrice as long as deep, entering the eye below the preocular, which is in contact with the frontal. Two (rarely three) postoculars. Temporals small, scale-like, 2 or 3 + 3 or 4. Upper labials eight (rarely seven or nine), third, fourth, and fifth (rarely fourth and fifth, or fourth, fifth, and sixth) entering the eye. Three or four lower labials in contact with the anterior chin-shields; posterior chin-shields very small and widely separated from each other by scales. _Scales_ with single or paired apical pits, in nineteen or twenty-one rows, usually nineteen in European specimens. Ventral shields 186 to 222; anal divided; subcaudals 48 to 73. _Coloration._--Greyish above, with 40 to 57 brown or black spots or bars on the body; a lateral series of smaller spots or vertical bars, alternating with the dorsals; the first spot, on the nape, elongate, usually with one or three linear processes in front, extending on the head (Plate XI.); usually a dark streak on each side of the head, from the eye to the angle of the mouth. Lower parts whitish, speckled, spotted, or marbled with grey or brown. Iris brown, with a golden circle round the pupil. _Size._--This species grows to a length of 2 feet 10 inches. _Distribution._--From Istria and Dalmatia to Greece, the Archipelago, Constantinople, Asia Minor, Cyprus, and Northern Syria; 2,600 feet appears to be its altitudinal limit. _Habits._--Although to a certain extent crepuscular or nocturnal, the Cat-snake is often seen hunting in the daytime, its food consisting almost exclusively of lizards, rarely of small mammals. Its movements are rather slow. The names Katzenschlange and _Ailurophis_, translated Cat-snake, probably originated from the way in which this snake stalks its prey, and suddenly pounces upon it. According to Eiffe, the poison causes the death of a _Lacerta vivipara_ in one minute, and P. de Grijs observed the larger _Lacerta agilis_ to die in two or three minutes. As a rule even fresh-caught specimens allow themselves to be handled without attempting to bite; some specimens, on the other hand, are very savage. Stony localities, old walls, and ruins, are the favourite abodes of this snake, which does well in captivity. _Reproduction._--Seven or eight eggs are laid in July; they measure about 1-1/4 inches in length and 1/2 inch in width. 20. TARBOPHIS IBERUS, Eichwald The Caucasian Cat-Snake