1881] ^^ [Cope. 



maxillary teeth. The last two are quite small, less than the usual maxil- 

 lary teeth. 



The dentary bones are very slender, and the distal end is somewhat thick- 

 ened to support two teeth larger than the others. These are the third and 

 fourth from the extremity, and are not quite so large as the large teeth of 

 the maxillary bone. The remaining mandibular teeth are small, and are 

 not so much compressed as in the species of Dimetrodon. Many of them 

 have only a posterior cutting edge, which is not denticulate. The apices 

 are strongly turned backwards in the posterior part of the series. The 

 posterior part of the dentary bone rises and carries some of the teeth 

 with it. 



The surface of the free edge of the internal plate ot the pterygoid 

 bone is granular. The teeth on the posterior edge of the same are sub- 

 conic, and in a single series. 



There are twenty-seven vertebrtE in a continuous series, from and inclu- 

 ding the axis. All bear diapophyses, and all are rib-bearing, except per- 

 haps the last two, where they are of reduced size. They are more or less 

 opposite the neural canal as far as the twenty-second centrum. On this 

 vertebra the superior edge is on a level with floor of the canal, and pos- 

 terior to this point the diapophyses rise from the centrum. Two sacrals 

 and ten caudals are preserved, and all have diapophyses and neural spines. 

 The centra in this species are rather short, being as deep as long through- 

 out the series, if measured at the middle. The edges are not undulate as 

 in C. {Embolophoras) limbatus Cope. The intercentra are short and not 

 extended upwards on the sides as in that species. 



Measurements. M, 



Length of quadrate bone 085 



Width of condyle of quadrate bone (greatest) 037 



Length from condyle of internal anterior process of do. .033 

 " external " " " .097 



" of squamosal bone (vertical) 124 



" " pterygoid from palatal foramen 116 



Width " " atmiddle 090 



Length" internal dentigerous edge of do 070 



" " posterior " " " 051 



" " maxillary bone posterior to canine brace 181 



Thickness of " " at canine brace C20 



Depth of " " "nostril 016 



Length of premaxillary bone (posterior apex restored).. .OCO 



Width •' " " at third tooth 023 



Diameter of large (first) premaxillary tooth 008 



" " " maxillary tooth (canine) 009 



" small " " 006 



Length of crown of last maxillary tooth 009 



" " twenty- seven continuous cervico-dorsal ver- 

 tebrae 855 



PROC. AMER. PHILOS. SOC. XXII. 117. E. PRINTED DECEMBER 19, 1884. 



