fORT UNIOX OF CRAZY M0UNTAI:N' FIELD, MOXT. 



133 



U.S.N.M. no. 9558, from the Gidley Quarry, is a left upper jaw 

 with M^"^ It closely resembles Mixodectes, occludes well with some 

 of the lower jaws of Eudaemonema cuspidata, and is not what would be 

 expected in the upper jaw of any other known species, so that I place 

 it here with some confidence. Aside from details of proportion, as 

 shown in the figures, the outstanding differences from Mixodectes are 

 the better development of the conules, especially the metaconule 

 (almost lacking in Mixodectes), and the even greater internal displace- 

 ment of the hypocone of M^. 



Table 29. — Measurements (in mm) of lower teeth of Eudaemonema cuspidata 



Genus EI.PIDOPHORU.S Simpson, 1927 



ELPIDOPHORUS MINOR, new species 



Figure 27 



Type. — Princeton no. 14201, left lower jaw with P3-M2. Collected 

 by A, C. Silberling. 



Horizon and locality. — Probably Silberling Quarr^^, Fort Union, 

 Middle Paleocene horizon, Crazy Mountain Field, Mont. 



Diagnosis. — Smaller than E. elegans or E. patratus. P^ slenderer 

 than in E. patratus, paraconids P4-M2 more strictly internal, heel of P4 

 smaller and less strongly basined, elevation of inner cusps P4-M2 

 distinct but slightly less pronounced than in E. patratus. 



Remarks. — The type and only known specimen was found by Silber- 

 ling on January 18, 1903, and is labeled as from the Torrejon, LocaUty 

 No. 2 (not of the serial list later started and employed in this work). 

 Mr. Silberling states that these data mean the No. 2 beds at or near 

 the Silberling Quarry. It is extraordinary that no further material of 

 this pecuhar form seems to occur in the much larger collections made 

 subsequently. 



The species is very distinct from the later E. patratus of this field, 

 and it will probably prove to be generically different, but they are 

 certainl}^ alUed and the present data do not seem to warrant generic 

 definition. E. minor resembles Eudaemonema more than does E. 



