COEYPHODON. 535 



two, which are equal. Tlie anterior is sHghtly concave in cross-section, 

 and the posterior slightly convex transversely, altliough concave longitu- 

 dinally. There is a weak ridge nearly parallel to and near the postero- 

 external angle, and traces of others on the postero-external face of the crown 

 in front of this one. The antero-internal angle is swollen at the base. 



The superior incisors present characteristic features. The ridge of the 

 external face, which is weakly developed in some of the species, and is 

 wanting in others, is here represented by a strong longitudinal angle, which 

 extends from the base of the crown to its apex, dividing the external face 

 into two distinct planes. This character is most marked on the external 

 incisor, where the planes are sub-equal, and concave. On the second the 

 anterior plane is smaller, and on the first it is a good deal smaller. These 

 incisors have a weak internal cingulum, but no external one. 



Measurements. 



M. 



Length of ramus from Pm. iv, inclusive „ 257 



Lengtli of inferior true molars 098 



Diameters of M.i inferior ^'^"t^™!"'^**^™'" ^^'^^ 



< transverse 020 



T^. . e-Ki ■■■ ■ r ■ < anteroposterior 036 



Diameters of M. Ill inferior^ ' „„ 



( transverse 029 



Depth of ramus at M. iii 075 



_. . -,, .. . < anteroposterior 0315 



Diameters of M. ii superior I ^ „„„ 



c transverse 039 



I longitudinal 094 



Diameters of crown of superior canine < anteroposterior 022 



( transverse 034 



_. , , CI ••■(vertical 022 



Diameters of crown ot I. lu •; 



( transverse 024 



The numerous characteristic marks show that this species is one of the 

 most distinct of the genus. It is also one of the largest, being second only 

 to the C. anax. 



From the Wasatch formation of the Big Horn ; J. L. Wortman. 



COEYPHODON MARGINATUS Cope. 



Paleontological Bulletin No. 34, p. 176, Feb., 1882. Proceed. Amer. Pliilos. Soc, 1881, Dec, p. 170, 



(1882.) 



Plate XLIVe; flg. 5. 



This is one of the smaller species, having nearly the dimensions of the 



