R. S. Lull — Fauna of the Dallas Sand Pits. 167 



Measurements of Cranium. 



Tetrameryx Antilocapra 



No. 1.50, No. 01518, 



S. M. U. Y. P. M. 



mm. Ratio mm. 



Breadth across orbits 112 0.82 136 



Breadth between base of ant. horns . . 44 0.76 58 



Width between summits, ant. horns. . 178 0.78 226 



Length from orbital rim, ant. horns .. . 110 1.15 95 



Length from orbital rim, post, horns. 297 



Width between summits, post, horns . . 275 



Ant.-post. diam., base of ant. horns.. 30 0.85 37 



Transverse diam., base of ant. horns . . 17 0.72 23.5 



Relationships. — There is no doubt that Tetrameryx 

 represents an aberrant genus of the family Antilocap- 

 ridaB, characterized by the heretofore unique feature of 

 deciduous horn sheaths over permanent cores, and differ- 

 ing from the typical genus, which it closely resembles in 

 size and dentition, by the presence of the additional 

 posterior horns and probably by the absence of the dis- 

 tinctive ^^ prong" on the horn sheaths of the recent genus. 

 It is a form which might well have arisen from the main 

 phylum in Pliocene or early Pleistocene time, and 

 because of its remarkable specialization represents a 

 short-lived race. The generic name (from rerpa-, four + 

 MP^i, ruminant) is self-explanatory, while the specific 

 name is given in honor of Professor Ellis W. Shuler, 

 through whose courtesy I am enabled to describe this 

 interesting form. 



Bison alleni Marsh. 



This species is represented by a well preserved left 

 ramus. Cat. No. 1.53, S. M. U. As it shows signs of 

 stream transportation, it must have come from the lower 

 level of Lagow's sand pit. The extremities of the bone 

 are lacking and it contains the alveoli of the canine, and 

 P2-3. P4 and M1-3 are present. The character of the 

 teeth and their dimensions compare very closely with 

 specimen No. 7706 in the U. S. National Museum referred 

 to B. alleni by Hay.* The original type, preserved at 

 Yale (Cat. No. 11911, Y. P. M.) consists of the horn-cores 

 and frontals only, but the reference of the National 

 Museum^ skull seems unquestionably correct, and further 

 description of the Dallas specimen unnecessary. 



' O. p. Hay, Proc. U. S. Nat. Miis., 46, 183, 1913. 



