PLATE XXVIII. 



I'AGE. 



, I . Ptyonius Vinehellianus. Twice natural size 376 



2. Ftifonius pef,tinatu!<, Cope. Ttie upper riglithand figure, P. J/arsAu. Natural size 377 



'3. Ptyonins Marshii, Cope. "Natural size ". 375 



4. Ptyonius peetinatus,. Cope. Natural size 377 



5. Ptyonius ? sernila, Cope. Natural size 37;) 



6. Ptyonius peetinatus, Cope. Natural size 377 



