4 



University of California Publications. [Geology 



eiated with these, as a very prominent and persistent feature, is 

 a heavy rhyolite flow. Some of the beds beneath the rhyolite 

 evidently represent old alluvial floors which have been built up 

 largely by dust accumulations. 



Although the Carnivora of the Tertiary faunas of the John 

 Day region have been known through numerous types, the actual 

 number of specimens is not large, and they may be counted as 

 among the rarities. It is interesting to note that in the collec- 

 tions obtained by the University of California, there is a consid- 

 erable percentage of new forms, although the number of speci- 

 mens is relatively small. This indicates that the fauna is still 

 only imperfectly represented in the collections. As yet, carni- 

 vore remains are certainly known only from the John Day and 

 Mascall. 



As far as possible in our field work, the effort has been made 

 to determine the stratigraphic horizons in which specimens have 

 been found. While the results of this discrimination have been 

 most apparent in the study of the Ungulata, some light has also 

 been thrown on the history of the Carnivora. Of the known car- 

 nivore species from this region there are still a considerable num- 

 ber of which the geological range or occurrence is unknown. As 

 far as has been determined, the following are the time relations 

 of the species. The number of specimens known to occur at each 

 horizon is indicated by the figures in the table. 



Middle 

 .lolin Day 



Cains ( ?) sp 



Tephrocyon rurestris 



Cynodictis ( ?) oregonensis 2 



Nothocyon geismarianus mollis . 1 



Nothocyon lemar 3 



Nothocyon latidens (?) 2 



Mesocyon coryphaeus 2 



Mesocyon brachyops 



Mesocyon josephi (?) 1 



Temnocyon altigenis 2 



Temnocyon ferox 



Philotrox condoni 1 



Archaelurus debilis major 7 



Nimravus gomphodus - 1 



Pogonodon davisi .... 



Pogonodon platycopis 1 



Upper 

 John Day 



3(?) 

 5 



1(?) 



1(?) 

 1 



Mascall 



1(?) 

 1 



