297 



Greensand, No. 4, of New Jersey ; also, Alabama, Mississippi, and No. 2 

 of Kansas ; (I have not seen it from No. 3). 



Lamna ?cuspidata, Agassiz. 



Leidy, Eepoit of tbc United States Geological Survey, I, p. 304, Plate XVIII, 44-45. 



Cretaceous No. 3 or Niobrara epoch, of Kansas. 



Lamna maceukhiza, Cope, sp. no\i. Plate XLIl, figs. 5-7. 



Established on four teeth from Kansas, which are distinguished by a 

 number of peculiarities. The crown is of the slender type, with the diame- 

 ters of the basis subequal, and the axis of the crown nearly straight. The 

 base is very oblique ; the plane face descending far below the convex ; the 

 roots rising on the latter to a point more than one-third the length from 

 the basis of the cementum, and forming a strong protuberance. There is a 

 denticle on each side, standing on a protuberance of the root, vertically below 

 the flat face of the crown at the inferior apex of the cementum ; standing 

 thus interior as well as lateral to the principal crown. The roots are con- 

 tinued some distance below these. The enamel is smooth, except at the base 

 of the flat face, where it and the denticles as well are strongly striate-ridged. 

 This striation occupies the opposite side of the tooth from that observed in 

 several other species. Length (total), 0'".027 ; of crown in front, 0'".012 ; 

 behind, 0™.020 ; of root behind, O^.OIO ; diameter of crown at base, longi- 

 tudinal, O-^.OOG ; transverse, O^.OOG. 



Ellis County, Kansas, Niobrara epoch. 



Lamna mudgei. Cope, sp. nov. Plate XLII, fig. 8. 



Indicated by three teeth from the Niobrara epoch of Kansas, and one 

 from greensand, No. 4, of New Jersey. These teeth are rather stout, espe- 

 cially at the base, ?nd the crown not very elongate. The root is excessively 

 protuberant, projecting horizontally beyond the convex side, and flat or 

 truncate below the protuberance. The enamel is entirely smooth. Measure- 

 ments of the New Jersey specimen : length of crown, 0'°.014 ; diameter 

 of base, longitudinal, 0°.004 ; transverse. 0".007 ; long diameter of roots at 

 basis of crown, O^.OOS. 



Dedicated to Professor Mudge, of Kansas. 



38 c 



