(Plate VIII. fig. D.)
This species has hitherto been confounded by Herpetologists with T. sexlineatus; we have four specimens before us, which show that the characters by which we distinguish this species are constant. It is as slender as the species from the East Indian Archipelago, with the snout produced and with the tail exceedingly long. The arrangement of the head-shields is the same in all the four species, except that T. japonicus has four pairs of chin-shields: one przefrontal, two postfrontals, one vertical, two pairs of occipitals with one or two odd central ones, the anterior occipitals being much smaller than the lateral. The nasal opening is in a single shield, immediately above the first labial; one freenal, one ante orbital, six upper and five lower labials; temples covered with very small keeled scales. The scales on the back are rounded behind; a strong ridge along each of the series of scales. The scales on the throat are similar to, and gradually pass into, those of the belly, the collar being very indistinct; there is a small fold before each shoulder. The ventral shields are sub quadrangular, imbricate, obtusely pointed behind, and arranged in twelve longitudinal and twenty-five transverse series. The scales on the tail are arranged in rings and strongly keeled, the keels forming continuous ridges as on the back and belly. Limbs slender, rather feeble; the anterior do not extend to the end of the snout, nor the posterior to the axil. Claws very feeble. Only one inguinal pore on each side.

Back brownish olive; a dark-brown band runs from the snout, through the eye, above the tympanum, to the loin; this band is separated from the colour of the back by an iridescent lateral stripe.
This species is found in Southern China, and probably also in Cochinchina.

Length of the head 5 lines, of the trunk 18 lines, of the tail 71 inches. The two figures marked 0, on Plate VIII., show the four dorsal series of scales and the single inguinal pore on each side.