R. W. Chanei/— Flora of Payette Formation, 219 



tion). Although it also occurs in the Chalk Bluffs 

 locality of the Auriferous Gravels, which is commonly 

 considered to be of Eocene age, Lesquereux states (4, p. 

 11) that it is more characteristic at the Table Mountain 

 locality. A recent study of the type material of Acer 

 bendirei, one of the most typical Miocene species in the 

 west, tends to show that it is to be referred to the genus 

 Platanus rather than Acer, and that certain specimens 

 of Platanus dissect a are identical with it. Platanus 

 dissect a is one of the more common species of the Pay- 

 ette flora, and is of wide occurrence in the Miocene of 

 several adjacent states. Clearly it is a strong indicator 

 of the Miocene age of the Payette. Likewise, Uhnus 

 calif o mica of the Payette flora has a Miocene distributioD 

 in the John Day Basin, at Table Mountain, California, 

 and at Ellensburg, Washington. It, too, occurs in the 

 Eocene horizon of the Auriferous Gravels, probably as 

 a geologic pioneer, for it is not recorded elsewhere from 

 the Eocene. In the same way, Sapindus oregonianus, 

 which is one of the more abundant species of the Payette, 

 is found in at least three widely separated Miocene 

 localities of Oregon, and has never been noted outside 

 of this system. 



A close similarity between certain Payette species 

 and living forms is again taken as an indication of the 

 closer relation of the Payette flora to the Miocene 

 than to the Eocene. The similarity of three new species 

 to modern representatives of their genera has already 

 been mentioned; Quercus n. sp. is strikingly like the 

 western Q. clirysolepis now living in California; Betula 

 n. sp. closely resembles B. occidentalis of the Pacific 

 Coast ; and Acer n. sp. is hardly to be distinguished from 

 Acer glabrnm, also a tree of the west. Of the previously 

 described species. Knowlton comments 5 on the simi- 

 larity of Aesculus simulata to Ac. oclandra and glabra 

 of the eastern United States ; he names Populus eotremu- 

 loides* having in mind a close relation with the living 

 P. tremuloides; certain specimens of Populus lindgreni 

 have a striking resemblance to living poplars of 

 the balsamifera type; Lesquereux 7 mentions a simi- 



5 Knowlton, F. H. : Fossil Flora of the John Dav Basin, Ore., p. 78. 



6 Knowlton, F. H. : Fossil Plants of the Payette Formation, p. 725. 



' Lesquereux, Leo : Fossil Plants of the Auriferous Gravel Deposits, pp. 

 11 and 16. l ' F1 



