■296 



of fouiteeii specimens of toctli obtained by Dr. George M. Sternberg, United 

 States Army, from the banks of Chalk Bluff Creek, a branch of Smoky Hill 

 River, about sixty miles east of Fort Wallace, Kansas. The specimens were 

 found in two parcels, each together, as if pertaiuiug to two individuals. 



The two largest teeth, of which one is represented in Figs. 1, 2, Plate 

 XVIII, are probably from a median position in the mouth or jaws. They 

 are symmetrical in form, and in outline arc transversely quadrate oblong with 

 rounded angles. 



The ci"ovvn is prominently convex, with the front and lateral borders nearly 

 straight, the back border slightly concave, and the angles rounded. Poste- 

 riorly it is impressed with a moderately concave crescentoid sinus. The 

 summit is crossed l)y a short transverse ridge, from which numerous ridges 

 radiate. Descending on the sides of the crown the ridges branch, and about 

 half way down terminate in a fine reticulation which extends to the borders 

 of the tooth. The root is a quadrate plate with the same outline of form as 

 the border of the crown. 



Three other specimens of the same parcel as the preceding appear to 

 have been lateral teeth in relation to them in position in the mouth. They 

 are nearly alike in shape and size ; one of them -being represented in Figs. 

 3, 4. They are not symmetrical as in the larger teeth, and their onthne 

 is more reniform. They are proportionately narrower at one side, and wider 

 and more extended on a base beyond the conical elevation of the crown at 

 the other side. The sinus is of less height, and the ridges of the crown 

 are more convergent at the apex of the cone. The root appears to recede 

 from the narrower side and reaches nearly to the edge of the crown on the 

 opposite side. The remaining two teeth of the same parcel have the same 

 character as those just described, but are considerably smaller. 



Measurements of some of the specimens are as follows : 



Breadth transversely 



Breadth antero-posteriorly . 

 Height from bottom of root 



Lines. 



1.3 



Of the two largest teeth, of the second parcel, which are nearly alike, one 

 is represented in Figs. 5 and G. They are intermediate in character to those 



