392 



PALEONTOLOGY OF OHIO. 



Owen, while the thoracic plates and lack of ventral scuta separate it 

 from Sauropleura. The plates may, however, be found in the latter; 

 should the scuta be found in Tuditanus, which is not probable, these genera 

 must be united. I associate with the T. punctulatus and T. brevirostris 

 three other species, known only from crania, a reference to be finally 

 criticized when more is known of them. They are all evidently allied. 

 The largest is T. radiatus, named from elevated radiating ridges of the 

 cranial sculpture; T. mordax has a strongly sculptured cranium, and 

 large premaxillary teeth, while in T. ohtusus the orbits are less anterior, 

 and the teeth small. I formerly described it as a Dendrerpeton. 



Tuditanus punctulatus, Cope. 



Transactions American Philosophical Society, April, 1874. 



This Amphibian is known from a single individual well preserved on 

 the opposite halves of a block of slate. The head, fore limbs, and 

 twenty-three consecutive vertebrae, with ribs, are well defined, but of 

 pelvis and hind limbs nothing is visible. 



The cranium is less expanded posteriorly than in the other species re- 

 ferred to the genus, and has a triangular outline, with narrowed but ob- 

 tuse muzzle. If I do not mistake the outline of the left orbit, it is near 

 the transverse line which divides the head equally. The surface of a 

 considerable portion is preserved, and is sculptured by small pits placed 

 closely, the intervals in a very few parts assuming the form of ridges. 

 The sculpture is thus more minute than in any other species. The 

 under jaw of the right side is partially preserved, and displays longi- 

 tudinal grooves. The ramus is stout and straight, and approaches the 

 form seen in Brachydectes Newherryi. Its teeth are not preserved, but the 

 extremities of the opposing maxillaries remain. They are small and 

 acutely conic ; both they and the ramus are much less robust than in the 

 above mentioned species, and the enamel preserved is smooth. 



The three pectoral shields are preserved, and as the exposed surface is 

 the interior, it is smooth. The laterals resemble imperfectly spherical 

 triangles. The outer margin is thin and convex, and the anterior angle 

 curves round the apex of the median shield and joins that of the oppo- 

 site side, forming a coarse interlocking suture. The median scuta is 

 formed like some of the patterns of ancient mirrors. It is a wide oval 

 excavated on each side behind, and produced from between these concavi- 

 ties into a long, flat, sternum-like process. The latter thus resembles 

 the xiphisternal production of frogs and of some lizards : as in the former 

 the ribs, having no hasmal elements, have no connection with it. Its 

 extremity is simple and obtuse. 



