Cope, Trans. Am. Phil. Soc., XIV, p. 15, 1869. Cope, Geol. Surv. Ohio, II, pt. II, p. 403, pl. xxxvii, fig. 1, 1875. Type: Specimen No. 8004 G, American Museum of Natural History. Horizon and locality: Linton, Ohio, Coal Measures. (Plate 20, fig. 4.) This species is represented by a single individual which is quite distinct from other members of the genus. The specimen has been spread over a surface of the coal, and exhibits ventral armature, dorsal region with ribs, and anterior and posterior limbs. Skull and caudal region not present. The ventral armature is arranged in parallel lines directed obliquely forwards and continuous on the median line, forming there a chevron. The individual elements are oat-shaped, and acuminate at both ends. They are moderately imbricate in an antero-posterior section. On the pectoral region between the fore limbs the series of scutellæ assume different directions, forming chevrons directed backwards, and forming with those of the belly a complete =X=. The humerus, ulna, and radius are rather stout, and of a size relative to the body, as in common types of existing lizards; the ulna and radius separate. The carpus is cartilaginous; the digits are 5 well-developed fingers having phalanges in the following numbers, commencing on the inside: 3, 4, 5, 6, 5. The last phalanx of the second is obscured, and it is not positive that the number is as given; it is more probable that it was 4 than 3. The outer toe was more slender than the others; the distal phalanges of all the toes are stout, as in modern Caudata. The ribs are long and curved as in reptiles, and judging by their distances the vertebræ are short; the latter are not well-defined, but there is no indication of prominent spines of any kind. The pelvic bones and portions of the hind limbs are present, but so obscured and confused as not to be easily made out. Enough remains to show that the hind limbs were longer than the fore. Thirteen ribs on one side and twelve on the other are preserved, with short ribs in the sacral region. The specimen is very indistinct and it is difficult for one to be sure of all the characters described by Cope. Measurements of the Type of Sauropleura digitata Cope. mm. Length of specimen 115 Greatest width 80 Diameter of ventral scute .75 Length of rib 15 Width of rib 1 Length of humerus 20 Length of radius 10 Length of ulna 9 Length of metacarpal 4 Length of fourth digit of hand 22 Length of interclavicle 20 Width of interclavicle 11