410 PROCEEDINGS OP THE ACADEMY OP 



vertebra with keeled centrum is undulate. The obtuse inferior 

 face of another dorsal is rugulose, and the edge of the articular 

 face is not undulate. The inferior faces of two caudals are marked 

 with two fine parallel grooves, while in another caudal and the 

 ?sacrals the same is smooth. There are some longitudinal ridges 

 on the upper side of the larger caudal. The coracoid is concave 

 on its inferior side, convex on its superior; the inner and anterior 

 borders are thickened by flaring of the edges. Surface smooth. 

 The posterior edge is thin, and is notched just behind the glenoid 

 facet. The proximal facets of the phalanges are shallow, simple, 

 and more or less transverse. 



M. 



Length centrum of axis .006 



Width do. at middle behind 008 



Depth do. (oblique) 010 



Length centrum of sharp-keeled dorsal 014 



Depth do. behind 012 



Width do. behind 012 



Length centrum of rounded dorsal 012 



Depth do. behind 011 



Width do. behind 0105 



Width neural canal of do 004 



Length centrum of larger caudal 014 



Width of do 0085 



Depth of do 008 



Length of base of neural arch of do. ..... .008 



Length of smaller caudal 0105 



Depth centrum of do 007 



Width " " 007 



Width of rib-head 010 



Length of coracoid 024 



Width of " 019 



Diameter of glenoid facet (transverse) 009 



Diameter of inner border (vertical) 006 



Length of a phalange 010 



Depth proximally .004 



Width " ... 007 



This species was of smaller size than the Gricotus heteroclitus. 

 It is dedicated to John Collett, of Newport, Indiana, of the State 

 Geological Survey. 



Ceratodus vinslovii, Cope. 



Represented by a tooth in good preservation, lacking only a 

 fragment of one end, and a portion of the inner margin of the base. 



