The impression of the larger animal (No. 803, Yale University Museum), which is probably an adult, presents the following elements: the entire skull, both humeri, impressions of posterior and anterior ventral armature, portions of the alimentary canal, one femur, portions of a fibula and tibia, and the entire impression of the tail, on which, as in _Micrerpeton caudatum_, there occur two definite dark lines, one beginning at the tip of the tail and running obliquely along the tail to where the impression is broken at the anal region; the other beginning at a distance of 4.5 mm. from the tip and running almost parallel with the median line. These two lines undoubtedly represent the lateral-line system. The skull is especially noted for its shortness and the great posterior width, as well as for the almost entire absence of the tympanic notch. The pineal foramen is located on a line with the posterior border of the orbits. The eyes themselves are narrow and acuminate at each end, with a pronounced convexity inwards and a flattening on the outer margin. They are located on the very border of the skull, but relatively more posterior than in _Micrerpeton_. No sclerotic plates are evident. The median suture can be indistinctly observed running the entire length of the skull. The sutures bounding the outside of the f rentals and the squamosals are partially evident, but not satisfactorily preserved. The mandible is represented by a mold which in wax impression shows short, stumpy teeth. Posterior to the skull at a distance of a millimeter there are two sharp impressions which may represent the anterior edges of the interclavicle or they may be branchial elements. They are distinctly curved, however, and probably represent portions of the interclavicle. A wax impression does not show a discrete structure, but the boundaries of some larger element. No other remains of the pectoral girdle can be discerned. The humeri are short and relatively thick. Wax impressions show them to have had truncate or slightly concave ends, thus indicating the absence or slight development of the endochondrium. No other elements of the arm are preserved. The impression of an elongate femur and the heads of the tibia and fibula of the left side are preserved. The ventral armature is preserved in two small patches, and these show the chevron-shaped rods to have been very fine much more delicate than in _Micrerpeton_. The body impression is very instructive and interesting, both in showing the form of the body and because in it are preserved the larger portions of the alimentary canal. The form of the body can best be discerned by reference to the figures (plate 3, figs. 1 and 2; plate 5, fig. 1).