Sinclair — A Large Parasuchian. 459 



and centrum and curves backward, bearing at its distal 

 end a slightly concave facet for articulation with the first 

 sacral rib, but, owing to crushing, the parts cannot be 

 brought into contact in their present position. In the 

 anterior thoracic vertebrae (not figured), the capitular 

 facet for the rib is placed low down on, and in conjunction 

 with, the anterior rim of the centrum. The tubercular 

 articulation evidently arose from the neural arch, but 

 has been broken off. The articular surfaces of the cen- 

 trum are concave anteriorly, less so posteriorly. In the 

 last presacral and anterior caudal the centra are concave 

 in front and almost plane behind. Both surfaces of the 

 centrum are plane in the sacral vertebra. The rib, shown 

 in outline in fig. 11, evidently belongs in the anterior por- 

 tion of the thoracic series, as the capitular and tubercular 

 facets are widely separated. 



As no teeth are associated with the type of Rutiodon 

 manhattanensis, those belonging to the specimen here 

 described are doubly interesting. They combine charac- 

 ters distributed among various supposedly dinosaurian 

 genera (Palceoctonus, Clepsysaurus) described by Cope 

 from the Triassic of Phoenixville, Pennsylvania, and as 

 there is every reason to believe that the teeth illustrated 

 in fig 1 belong to a single individual, probably several of 

 the Phoenixville dinosaurs are really Parasuchians and 

 identical with Rutiodon manhattanensis. If found sep- 

 arately, teeth of the different shapes here described 

 might well be referred to two or more genera. Some are 

 conical, with the surface of the enamel showing a "silky 

 sculpture of minute raised lines" (Cope), with the base 

 of the crown grooved longitudinally on the outer side and 

 with serrate cutting edges extending almost to the base 

 of the crown, separated by unequal convex surfaces (fig. 

 la). In other teeth of similar shape (fig. lb) serrations 

 may be wanting on the cutting edges and the latter 

 limited to the apical portion of the crown, which is finely 



Figs. 1-4. Rutiodon manliattanevsis, No. 11544, Princeton University 

 Geological Museum. In-.?. Series of teeth showing some of the different 

 forms. In all cross-sections, the lower edge of the outline corresponds to 

 the surface of the tooth seen in the drawing, s Indicates position of 

 serrated cutting edges. 2. Last presacral vertebra from the left side. 

 s indicates the facet for contact with the expanded base of the first sacral 

 rib. 3. First sacral vertebra from in front, s indicates facet on expanded 

 rib base for contact with the centrum of the last presacral. 4. Left femur 

 from the outer side. 



All figures one-third the natural size. 



