1852.] 177 Crotalus LUCIFER, B. and G. Head subcircular or elliptical, nearly one inch and a quarter in length, covered on the vertex with very small and polygonal scales, elliptical and slightly carinated on the occipital region. One large supra orbital scutella obliquely striated. Eyes proportionally small, ten large anterior orbital plates ; the upper one, which is the longest, is polygonal, whilst the lower one is triangular. The rostral plate is rather small, pointed above, higher than broad and pentagonal in form. The general color is reddish brown above, deeper along the dorsal line than on the sides, yellowish beneath. For two-thirds of the length there exists on the back a series of subcircular white rings lined internally with a narrow, black line. There are on the sides a series of irregular blotches which extend to the belly. The posterior third of the body is alternately semi-annulated above with black and yellow, the yellow, however, being much narrower than the black. From Oregon and California. Emys marmorata, B. and G. The shape of the shell seen from above is regu-larly elliptical, slightly concave anteriorly, with a small notch behind. It is rather depressed and provided with a slight dorsal keel. Ventral shield rounded in front, openly concave behind. The tail is very slender and tapering. The posterior nails are stouter than the anterior ones and very much arched. The color is yellowish brown marbled with black. The largest specimen under examination measures four inches in length from the tip of the snout to the end of the tail ; the shell itself being only two inches and three-eighths in length and a little over two inches in width. From Puget Sound. The Committee on Dr. Hallowell's descriptions of new ReptileS; re-ported in favor of publication in tlie Proceedings. Descnpttdns of neio Species of Reptiles inhabiting North America. By Edward Hallowell, M. D. Tropidonotus rhombifer. Sp. Char. Head elongated, depressed, slightly swollen at the temples ; a series of dark colored rhomboid spots upon the back, presenting the form of triangles, their apices posteriorly and anteriorly touching each other; a row of dark colored transverse bars upon the sides, uniting with the lateral inferior extremities of the rhomboid spots upon the back ; a series of dark colored bands upon the tail ; abdomen wnd under part of tail more or less maculated ; scuta very strongly carinated: 25 rows of carinated scales; abdominal scuta 142; sub-caudal 70. Dimensions. Length of head l^^ inches (Fr.) ; greatest breadth posteriorly 10 lines; length of body 2 ft. ; of tail 6^ inches ; total length 2 ft. 8 inches. Habitat. Arkansas river and its tributaries, near the northern boundary of the Creek Nation ; found abundantly on the borders of streams. Dr. Wood-house observed one with many young on one of the sand banks of the Arkansas river. Tropidonotus transversus. Sp. Char. Head large, swollen at the temples, convex posteriorly, flattened between the orbits, depressed in front ; a series of subquadrate dark colored blotches, thirty-six or thirty-seven in number, along the back ; a transverse row of oblong bars along the sides, their upper margins alternating with the inferior margins of the dorsal blotches; scales strongly carinated, 23 rows; abdominal scuta 144; sub-caudal 78. Dimensions. Length of head 12 lines; greatest breadth 7; length of body 1 ft. (Fr.) 5 inches 7 lines ; length of tail 6 inches; total length 2 ft. Habitat. Creek boundary, found near the banks of the Arkansas and its tri-butaries.