Type: Specimen No. 6699, U. S. National Museum.
Horizon and locality: Coal Measures of Washington County, Kansas.
The species is represented in the collections of the U. S. National Museum by a fragment of the skull, with portions of two ribs (Cat. No. 6699, Vert. Pal. U. S. Nat. Mus.) and the larger part of the left ramus of the mandible (Cat. No. 6680, Vert. Pal. U. S. Nat. Mus.). The mandible was preserved in a large block of coal which contained the impression of the back portion of the mandible from which the bone had been weathered. It was possible to remove the bone and make a plaster cast of the impression. This shows in a very satisfactory manner all of the characters of the external surface.
Skull.—Only a portion of the left maxilla, with 14 teeth, and a part of the nasal are preserved. The skull seems to have been laterally crushed and the right side of the skull has been crushed flat under the left. It has not seemed feasible to remove the skull from the matrix.
The teeth are uniform, rather short, bluntly conical, curved backward, and coarsely striate. They are somewhat crowded, the bases being separated from each other by only a fraction of a millimeter.
The maxilla and portion of the nasal are coarsely sculptured with elongate pits and ridges. A portion of the infraorbital lateral-line canal is preserved. It is simply a rounded groove with three short branches. It lies near the middle of the maxilla.
Mandible.—It has been possible to study both sides of the mandible. The left ramus was preserved in the coal, with its inner face exposed. This face is broken by two large oval openings, the internal mandibular foramina. This is the term used by Reynolds for the openings on the inner surface of the alligator jaw. So far as I can ascertain, no other known labyrinthodont mandible displays this character in such a marked degree. Dr. Branson has figured in Anaschisma browni Branson from the Triassic ([49]) of Wyoming the inner surface of the left ramus, on which there are likewise two openings but differently situated. A similarity between the two mandibles is observed in that the suture separating the prearticular and angular touches the posterior edge of the posterior foramen.
Several of the sutures are well preserved and they have been indicated in the drawing ([fig. 42]). The pillar separating the two foramina is cut by the suture separating the angular and prearticular very much as in Anaschisma, with the difference that in the latter form the angular and prearticular are not approximated. I believe I detect the suture as represented separating the anterior end of the angular from the dentary and splenial. I am assured of the portion near the anterior foramen and also of the part near the tip of the ramus. This shows the angular to be a very elongate element, running very nearly the entire length of the mandible, much as in Anaschisma and other labyrinthodont genera. The splenial is a small, slender element located farther forward, where it has been shoved by the large-sized internal mandibular foramina. The prearticular is a rather long, broad element, of which only a portion is preserved. I am not sure as to the location of the suture for the dentary, unless it is represented by the line bounding the roughened area near the teeth. If this is true, the dentary is a large element, since it extends well down upon the outer side of the jaw. The dentary possesses evidences of 26 teeth, a few of which are completely preserved. Most of them are, however, represented either by bases or by impressions in the coal. The teeth are very similar to those of the maxilla, though slightly larger. The characters given for the maxillary teeth will suffice for those of the dentary.
