plastral shields very variable ; suture between gulars and humerals forming a right angle ; axillary and inguinal large. Head moderate ; snout short, rather pointed and prominent ; jaws with denticulated edge, upper not notched mesially ; alveolar surface of upper jaw with the median ridge nearer the inner than the outer border ; bony choanae between the orbits ; the width of the lower jaw at the symphysis is less than the diameter of the orbit. Fore limbs with large transverse scales. Carapace olive, that of young with some black spots, especially on the posterior edge of the first three vertebrals ; an orange vertebral band and a narrow yellow margin ; carapace more uniform in the adult ; plastron orange or red, with black spots, or brown with a yellowish anterior and lateral border to each shield, in one specimen uniform yellow. Head blackish ; jaws and sides of crown orange ; neck with numerous yellow lines on a blackish ground ; linibs dark olive, spotted with yellow.
Length of shell up to nearly 9 inches.
Hab. Ganges and Indus systems.
Family III. PLATYSTERNIDAE.
Shell covered with epidermal shields. Caudal vertebrae mostly opisthocoelous. Neck completely retractile within the shell. Parietal bones widely separated from squamosals ; temporal region completely roofed over. Digits moderately elongate ; phalanges with condyles ; claws four or five.
A single genus and species, remarkable for its large head and long tail.
Genus PLATYSTERNUM,
Gray, P.Z.S. 1831, p. 106.
Plastron moderately large, connected with the carapace by ligament ; a series of inframarginal shields separates the plastral shields from the marginals. Head very large, covered above with an undivided horny shield ; jaws very strong, hooked, without additional alveolar ridges. Digits feebly webbed, all except the outer toe clawed. Tail very long, subcylindrical, compressed at the end, with rings of squarish shields.
A single species.
43. Platysternum megacephalum.
Platyi-ternum megacephalum, Gray, P.Z.S. 1831, p. 107; id. III. Ind. Zool. ii, pi. Ixii ; Giinth. Kept. B. I. p. 43 ; Bouleng. Cat. Chd. &c. p. 46.
Platysternon peguense, Gray, Suppl. Cat. Sh. Rept. i, p. 70 ; Theob. Cat. p. 26.
