Leptophractus dentatus new species.
Type: Specimen No. 10850, American Museum of Natural History. Collected by Dr. J. S. Newberry.
Horizon and locality: Linton, Ohio, Coal Measures.
Fig. 36. Mandible of Leptophractus dentatus new species, from the Linton, Ohio, Coal Measures. × 1. Original in American Museum of Natural History.
The type is a single right mandible, nearly entire, of a rather large animal. The specific characters for the separation of the new form from the previously described L. obsoletus and L. lineolatus are the smaller size and slenderness of the mandible, associated with uniform teeth, which are slender and delicately fluted.
There are 17 teeth preserved, the largest of which is 8 mm. in length. From the posterior tooth the series gradually descends to half this length 0.5 inch from the anterior end of the mandible.
The exact form of the mandible can not be determined, but so far as can be seen it is very slender, coming almost to a point at the anterior end. The posterior portion is wide, but apparently not very heavy. There is a fragment associated with the specimen which discloses a few teeth, but its position in the cranium can not be determined.