490 University of California Publications in Geology [Vol. 10 



In size and shape the cave specimen (fig. 7) corresponds closely 

 to teeth of ill. harlani from Rancho La Brea. The latter from the 

 asphalt beds shows some range of variation in shape, snch variation 

 easily including the stage indicated by the first inferior tooth in the 

 type specimen. Curvature of the crown, inward twisting of the lower 

 portion on the long axis of the tooth, and anterior and posterior 

 beveling of the triturating surface are characters common to both 

 forms. The tooth from Hawver Cave and no. 21453 from Rancho 

 La Brea possess residual patches of cement enclosing the outer layer 

 of dentine, and in both specimens the concentric undulating lines on 

 the surface of the dentine are plainly seen. 



Fig. 7. Mylodon harlani Owen. First inferior tooth, no. 19891, outer view, 

 X Vo- Pleistocene of Hawver Cave, near Auburn, California. 



Figs. 8a and 8b. Mylodon harlani Owen. Phalanx 2, digit 2, manus, no. 

 19892, X V-2- Pleistocene of Hawver Cave, near Auburn, California. Fig. 8a, 

 lateral view; fig. 8b, superior view. 



Figs. 9a and 9b. Mylodon harlani Owen. Phalanx 2, digit 3, pes, no. 19893, 

 X Vo. Fig. 9a, superior view; fig. 9b, lateral view. Pleistocene of Hawver Cave, 

 near Auburn, California. 



Figs. 10a and 10b. Megalonyx{?) , sp. Second phalanx, no. 19863, X %• 

 Fig. 10a, superior view; fig. 10b, view of distal trochlea. Pleistocene of Hawver 

 Cave, near Auburn, California. 



