Cope, Trans. Amer. Phil. Soc., XV, p. 263, 1874.
Cope, Geol. Surv. Ohio, II, pt. II, p. 368, pl. xliii, fig. 1, 1875.
Type: Specimen No. 8617 G, American Museum of Natural History, collection of Dr. J. S. Newberry.
Horizon and locality: Linton, Ohio, Coal Measures.
This species is established by remains of 2 individuals, one embracing 16 and the other 14 vertebræ, with ribs. The neural arches, viewed from above, have a V-shaped outline posteriorly, from the fact that the broad zygapophyses meet on the median line and spread out distally over the broad anterior ones adjoining. The latter appear to be somewhat concave and to border the former exteriorly as well as inferiorly. The base of the neural spine extends to the posterior emargination, but not quite to the anterior. The breadth of the dorsal vertebræ above is equal from the emargination behind to the anterior margin of the anterior zygapophyses.
The ribs are long for an amphibian, but not long for a reptile. They are well curved, chiefly near the proximal extremity. The longest found, measured by a cord, equals two and two-fifths vertebræ. These vertebræ, measured along the median line above, equal 11 lines; one of these is 3.6 lines in width above. This animal has been, like Amphiuma, a snake-like amphibian, but was probably still larger. How near the affinities to this genus may be can not now be determined, owing to the want of many important parts of the skeleton, but it differs in the important feature of large, well-developed ribs. The size of the vertebræ would indicate a body of the size of the common rattlesnake (Crotalus horridus) and too large for Brachydectes newberryi, which is only known from jaws.
Fig. 32.—Drawing from Cope's figure of Molgophis brevicostatus Cope, × 0.5