1918] Stock: The Pleistocene Fauna of Hawver Cave 



501 



Reinhardt figures 19 a vertebra of the Brazilian Nothrotherium 

 which he refers to the fourth or fifth of the caudal series. The fifth 

 caudal from Hawver Cave differs from Reinhardt 's specimen in the 

 less prominent neural spine, broader posterior chevron facets, and 

 shape of transverse process. In the vertebra from the Brazilian 

 cavern this process is not deflected downward at the outer end, in 

 which respect it is more like that in vertebrae of Nothrotherium sit- 

 uated more anteriorly in the caudal series. 



Figs. 22a and 22fr. Nothrotherium sliastense hawveri, n. subsp. Chevron-bone, 

 no. 21474, X Fig. 22a, anterior view; fig. 22b, lateral view. Pleistocene 



of Hawver Cave, near Auburn, California. 



Figs. 23a, 23&, and 23c. Nothrotherium shastense hawveri, n. subsp. Sternal 

 segment, no. 19890, X %. Fig. 23a, lateral view; fig. 23b, inferior view; fig. 23c, 

 end view. Pleistocene of Hawver Cave, near Auburn, California. 



Specimen no. 21474, one of the chevron-bones, presumably of 

 Nothrotherium, is worthy of note because of its peculiar shape. In 

 contrast to the Y-shaped chevron-bones of Mylodon, the specimen 

 (figs. 22a, 22b) from Hawver Cave has the distal end broadened con- 

 siderably. The base forms a V with apex anteriorly and furnishes 

 a fully adequate support for the bone. Apparently the approximate 

 X-shape of the chevron-bone is due to a fusion of two lateral pieces, 

 each of which has a wide base. No. 21475 probably represents one of 

 these lateral pieces. In no. 21474 there has not been an entire fusion 



is Bernhardt, J., op. ext., pi. 2, figs. 4 and 5, 1878. 



