364 



PALEONTOLOGY OF OHIO. 



The presence of the maxillary bone furthermore excludes this genus 

 from near affinity to either the Trachystomata and Proteida, and allies 

 it to Amphiuma and Protonopsis. It differs from both these genera in 

 the absence of teeth from this bone as well as its apparently small de- 

 velopment. This may indicate that the animal was not fully grown- 

 In the hyoid region it differs from these in the apparent absence of the 

 second axialhyal and in points of the haemal segments. Thus the sec- 

 ond is confluent either with the first or second pleural element in those 

 genera, and the third haemal element is much reduced and does not sup- 

 port the fourth pleural in either. 



The present genus is, then, to be referred to the neighborhood of 

 Amphiuma and Protonopsis, but forming the type of another family. The 

 branchial apparatus is more archetypical or fish-like than in either of 

 these in (1) the three distinct and well-developed haemal branchihyals, 

 (2) the four distinct pleural elements of the same, and (3) the distinct (?) 

 stylohyal. 



Its weak maxillaries have a larval aspect, but the ossification of all 

 the bones, and the small size of the pleural branchihyals, as compared 

 with the rest of the cranium, render it probable that the form is no more 

 larval than the genera to whose neighborhood it is referred. That it 

 passed a portion of its existence as an aquatic branchiferous animal is 

 no less certain. 



COCTTINUS GYEINOIDES, Cope. 



Transac. Amer. Philos. Soc, 1874. 



The only specimen of this Batrachian embraces the inferior bones of 

 the cranium in a complete state of preservation, with the muzzle, with 

 its teeth ; also of the anterior eight vertebrae, with their ribs. The con- 

 dition of the hyal elements is as follows : The haemal element of the 

 first branchial arch is partially concealed on both sides by the cera- 

 tohyal. An expanded truncate face of attachment to the axial element 

 is visible on both sides, but the body of the bone is flat and presents the 

 edge in the specimen. The first pleural element proceeds from just be- 

 hind and within its extremity; it is longer than the other pleural ele- 

 ments. A slender bone is visible extending from the space between the 

 ceratohyal and mandibular angle ; it may, therefore, pertain to the sus- 

 pensorium of the jaw as well as to that of the hyoid arch, or be 

 squamosal as well as stylohyal. The second haemal bone is slender, but 

 with an enlarged axial extremity ; that of the right side is not so well 

 preserved as to be safely determined. The third hasmal elements are 



