268 



University of California Publications. 



[Geology 



portion of the parastylid ridge. Although considerably worn 

 the form of this tooth suggests that of M 2 in Macrotherium 

 grande. On the outer side of the tooth there is a well-marked 

 shelf connecting the trigonid and talonid portions. On the outer 

 side of the protoconid a slight ridge is developed on the cingulum. 

 On the corresponding region of the hypoeonid the surface is 

 smooth. Behind the hypoeonid region there is a prominent shelf 

 which slopes upward toward the distal end of the entoconid region. 



Measurements of Lower Molar, M 2 ?, No. 12595 



Greatest anteroposterior diameter 40.2 mm. 



Greatest transverse diameter 19.4 



Anterior posterior diameter of heel 22.3 



In an upper cheek-tooth, no. 12596 (fig. 39), evidently repre- 

 senting P 4 , the ectoloph is comparatively simple as in Moropus 

 elatus. The deuterocone is transversely compressed, while the 

 anterior and posterior ends of this cusp are connected with the 

 outer ridge. A deep pit or valley is formed between the outer 

 and inner ridges as in Moropus elatus, but the inner cusp seems 

 a little less like a simple crescent than in the corresponding tooth 

 of that species as figured by Peterson. 111 



Measurements of P 4 , No. 12596 



Greatest transverse diameter 26.3 mm. 



Greatest anteroposterior diameter 20.2 



Of the limb elements twelve phalangeal bones have been found 

 in Virgin Valley and at Little High Rock Canon. They evidently 

 represent both the fore and hind limbs. Two or three specimens 

 are apparently proximal phalanges not united with the second 

 phalange. One specimen, no. 19406 (fig. 43), shows the union 

 of the first and second phalanges. This bone is relatively large 

 and is much more compressed laterally than the other specimens. 

 It corresponds in form and size with the largest terminal 

 phalange present, and both probably belong to digit two of the 

 anterior limb. No specimens representing phalange two were 

 found that were not co-ossified with the proximal element. 



A very large terminal phalange (no. 19407) from Little High 

 Rock Canon (figs. 45a to 45c) evidently represents digit two of 



is Peterson, O. A., Amer. Natur., vol. 41, p. 741, fig. 25, 1907. 



