Known from a single vertebra. Spine very high and heavy, the neural canal large.
Proterpeton gurleyi new species.
Type: Specimen No. 13,296, Walker Museum, University of Chicago.
Horizon and locality: Coal Measures near Danville, Illinois.
The vertebra, as preserved, is well characterized by the figure ([plate 22, fig. 2]). The spine is high and heavy, the neural canal is large, and the centrum reduced. The form is very unusual. It is apparently from the cervical region, as there are no indications of zygapophyses, transverse processes, or hæmal arches, although they may have been abraded; apparently not, however. The type specimen was discovered near Danville, Illinois, about the horizon of the Danville coal, so that it is quite high in the Allegheny series of the Pennsylvanian and of about the same horizon as the phalangeal bone from Breeze, Illinois, which may be provisionally associated with this form. There is no assurance that Proterpeton gurleyi is an amphibian. The vertebra may have belonged to a fish.
| Measurements of the Type of Proterpeton gurleyi Moodie. | |
| mm. | |
| Entire height of vertebra | 24 |
| Width at side of neural canal | 21.5 |
| Width of neural canal | 13 |
| Height of neural canal (crushed?) | 6.5 |
| Width of vertebral centrum anteroposteriorly | 5.5 |
| Height of neural spine from top of neural canal | 9 |
Dawson, Phil. Trans. Roy. Soc. London, pt. 11, p. 644, pl. 40, figs. 57-61, 1882.
Type: Amblyodon problematicum Dawson.
This genus was described by Dawson in 1882 from very imperfect remains. He says that it is "characterized by stout cylindrical teeth, blunt at the apices; but otherwise imperfectly known."