WAGNER: TETRACAULODON (tETRABELODON) SHEPARDII. IOI 



2. Two upper last molars, belonging to opposite sides, seem- 

 ingly of the same jaw. Four crests and trace of fifth. Cingulum 

 distinct, especially on inner face. Inner halves of first three crests 

 trefoiled. (See Plate XXV) . 



Measurements: 



Diameter of right at base, anterio-posterior i6o mm 



Diameter of right at base, transverse, posterior end of sec- 

 ond crest 85 " 



Diameter of left at base, anterio-posterior 170 " 



Diameter of left, transverse, posterior end of second crest go " 



3. Some specimens of tusks in the Washburn museum I have 

 not seen, but Mr. F. J. Titt of that college has kindly sent me the 

 following notes thereon: 



Specimen A. (See cross section in Fig. A.), a fragment at the 

 end of a tusk 181^2 inches long, with a vertical diameter, at the 

 large end, 1^4 inches. This specimen has only a very small por- 

 tion of the enamel adhering to it. 



Specimen B. (See cross sections in Fig. B. ), a fragment 16 

 inches long, representing probably an injured tip. 



Measurements: 



Vertical diameter, large end 5 inches 



Vertical diameter, small end 3^3 " 



Horizontal diameter, large end 3^ " 



Horizontal diameter, small end 2 " 



Specimen C. (See cross section in Fig. C), a fragment of a tip 

 i6y2 inches long, very slightly curved. Its two diameters are 

 equal, 2^/^ inches. The tusk is characterized by ridges and shallow 

 grooves varying in width from J/j^ to i inch. 



These tusks all show bands of enamel running the length of the 

 tusk and covering about y:-, the circumference. 



Synonymy. — An attempt to construct a synonymy which would 

 be anywhere near complete, would lead too far afield. I shall 

 record therefore, only the names pertinent to this discussion. 



