Type: Specimen No. 8604 G, American Museum of Natural History.
Horizon and locality: Linton Ohio, Coal Measures. Cope (Geol. Surv. Ohio, vol. II, pt II, p. 388, 1875) says of this form:
"The species is represented by one nearly perfect ramus mandibuli, one dentary bone and one premaxillary, probably not complete.
"The dentary bone appears to have been attached by suture to the articular and angular, as its free margin has very much of the outline of that suture in Amphiuma and lizards. The coronoid process would also seem to be a part of the same bone as in Amphiuma and Menopema, and not composed of the coronoid bone as in lizards. It rises immediately behind the last tooth, and displays no suture.
"The lower portion of the dentary is prolonged into an acute angle. This is separated by a deep and wide concavity from the superior posterior prolongation, which is obtuse, and rises at once into the coronoid process. Teeth on this dentary, seven; the same number is on the preserved ramus; this number is suspected to be complete, or nearly so. The teeth terminate at the obvious termination of each ramus, which is, it is true, slightly obscured. These teeth are the longest in the Microsauria in relation to the depth of the ramus, equaling the largest in Œstocephalus. They are doubtless exposed, as are some of those of the last-named genus, by the splitting away of the outer parapet of the dentary bone. As no traces of alveoli have been thus rendered visible I suspect the dentition to have been acrodont, as in some existing Batrachia.
"No external surface of the mandible remains, but there are no impressions of sculpture on the matrix. A little external face of the premaxillary displays none.
"The species is dedicated to Professor John S. Newberry, the able director of the Geological Survey of Ohio, and discoverer of most of the Batrachia herein described."
| Measurements of the Type. | |
| mm. | |
| Length of ramus of mandible (imperfect) | 22 |
| Depth at last tooth | 5 |
| Length of exposed tooth | 3.5 |
| Length of dentary | 16 |
| Depth at coronoid process | 7.5 |
| Depth at first tooth | 3 |
Type: Proterpeton gurleyi Moodie.