370 PALJEONTOIiOGY OF OHIO. 



? parietal, on its outer side, a bony enlargement arises, whicli oontraets 

 outward and forward into a narrow element which curves forward be- 

 neath the ?postfrontal. These look like an anteriorly directed quad- 

 rate with articular bone, such as are seen in larvse and some adults of 

 existing Batrachians. These determinations will require confirmation 

 from additional material. In the meanwhile it is evident that the pres- 

 ent specimen can not be referred to any of the other species herein de- 

 scribed. 



Total length of specimen, 0.0650 m. ; total length of a rib, .0050; total 

 length of ? parietal and postfrontal bones, .0085 ; width of head at ? quad- 

 rate, .0080; length of a vertebra, .0020; depth of a vertebra, .0025. 



This animal is dedicated to Charles M. Wheatley, A.M., of Phoenix- 

 ville, Pennsylvania, one of the original investigators of the deposit in 

 which it occurs. 



Pleueoptyx, Cope. 



The specimens on which the species of this genus repose do not ex- 

 lliibit crania. The five — probably six — specimens which represent them 

 •offer various views of the vertebral column, and in none is there any 

 trace of ventral or thoracic armature. Limbs can be ascribed to the 

 ,genus with probability only. The vertebrae are of moderate length, with 

 well-developed zygapophyses, and a short and not very elevated neural 

 .spine in the dorsal region, which is not sculptured in any way. The 

 :generic character is seen in the ribs. These are rather short and very 

 stou't, and support an ala on the posterior or convex border, which ex- 

 jpands downwards, and then suddenly contracts to the shaft. The ex- 

 tremity of the latter is broad and truncate, and includes a medullary 

 •cavity, which is only partially fitted with cancellated tissue. 



The general appearance of the species of Pleuroptyx is that of the Mol- 

 gophis, so far as known, but nothing resembling the peculiar structure of 

 jthe ribs is seen in any other. 



Pleueoptyx clavatus, Cope. 



Parts of two individuals express the typical characters of this species, 

 -while a third only differs in being considerably smaller. A fourth may 

 very probably be referred here, and another, bearing several elements of 

 a leg, should be most likely associated with the last mentioned. 



The ribs are considerably narrowed near the head, and appear to possess 

 .a low tubercular process some distance below it. The shaft is curved 



