1 62 MAURICE G. MEHL 



that one can never safely refer other material to it/ The species 

 F. cylindricon, then (the form first described), is the type and only 

 species of this genus, and the form described by von Meyer as 

 Belodon kapffi should be considered distinct. 



2. Belodon von Meyer 



B. plieningeri von Meyer 



B. (Mystriosuchus) rutimeyeri F. von Huene 

 The genus Belodon, of which B. plieningeri is the type, was pro- 

 posed in 1842^ for a form with a slender rostrum and laterally com- 

 pressed, arrowhead-shaped posterior teeth. 



3. Mystriosuchus E. Fraas 



M. (Belodon) planirostris H. von Meyer 

 This form differs from the genus Belodon chiefly in that the 

 teeth of the former are all round in cross-section. 



4. Rutiodon Emmons^ 



R. carolinensis Emmons 



R. manhattanensis von Huene 



The writer has followed McGregor in uniting in the first species 

 most of the many specimens that have been described from the 

 Trias of the eastern United States under the following names: 



Clepsysaurus pennsylvanicus I. Lea. 



Centemodon sulcatus I. Lea. 



Omosaurus perplexus J. Leidy. 



Palaeosaurus sulcaius E. Emmons. 



Palaeosaurus carolinensis E. Emmons. 



Compsosaurus priscus J. Leidy. 



Clepsisaurus leaii E. Emmons. 



Eurydorus serridus J. Leidy. 



Belodon carolinensis E. D. Cope. 



Belodon priscus Cope. 



Belodon lepturus Cope. 



Belodon leaii Cope. 



Rhytiodon rostratus O. C. Marsh. 



( ?) Beldon validus Marsh (doubtful, never figured) . 



' Although the writer has not seen this material, he has been informed by no less 

 an authority than Dr. S. W. WiUiston, who has recently had the opportunity to 

 examine the type remains, that the preservation is such that one can in nowise be 

 certain of its generic identity. 



^ Von Meyer, Neiies Jahrb. f. Mineralogie. 



3 Geological report on the midland counties of North Carolina. 



