112 FOSSIL FLORA OF THE JOHIST DAY BASIN, OREGON. [bull. 204, 

 THE DALLES, OREGON. 



By the kindness of Dr. Arthur Hollick I have been enabled to 

 examine a number of unpul)li.shed plates of fossil plants by the late 

 Dr. NewberiT, on which are depicted several species from the so-called 

 Dalles group, at the Dalles of the Cohimbia. The matrix, 1 am 

 informed by Dr. Hollick, is a whitish, very coarse-g-rained volcanic 

 ash, identical in appearance with that ))earing fossil plants at Kell}^ 

 Hollow, Wenas Valley, near Ellensburg, Washington. These plates 

 were not published by Dr. Newberry and simply bear provisional 

 names penciled on the margins of the plates. These species are 

 represented as follows: 



Acacia, or Cassia sp, — A small, even-pinnate compound leaf of 

 numerous small oblong leaflets. Nothing similar has been thus far 

 found in the John Day Basin. 



'"'' Myrlca dirersifoUa Lesq." — Two figures of this form are shown. 

 They appear to be the same as CratcBgus famscens Newb., from 

 Bridge Creek. 



" Ulmus sp." — Two small, coarsely toothed leaves with well-marked 

 secondaries ending in the marginal teeth. Judging from the drawings 

 alone I should incline to refer these leaves to a small form of Carpinus 

 gTandis Unger, very similar to some forms found at Bridge Creek, 

 and not to Ulmus. They are wholly unlike the common elm leaves 

 that are abundant at this latter locality. 



With only these data available 1 should incline to regard the locality 

 affording them as referable to the same age as the Bridge Creek beds, 

 viz, Upper Clarno. 



From the facts here adduced it seems beyond dispute that the condi- 

 tions which prevailed in the John Day Basin during Tertiary times 

 were much more far reaching than the mere local limits of the basin; 

 in other words, that the formations there recognized extended as far 

 north as central Washington, east into northwestern Idaho, and west- 

 ward over much of western Oregon. 



SUMMARY. 



(1) The John Day Basin lies between the north and south ranges of 

 the Blue Mountains, in north-central Oregon. It covers an area of 

 approximately 10,OUO square miles and is drained by John Day River 

 and its tributaries. It has been the scene of great volcanic activity, 

 its rock masses l)eing made up of numerous volcanic flows, with alter- 

 nations of ashes, tufas, sands, and gravels. 



(2) No detailed geological study has been made of the region, but 

 c()ntril>uti()ns to this subject have been made l)v Le Conte, Condon, 

 Marsh, Cope, Wortman, Matthew, and Merriam, the most important 

 and comprehensive being by the latter author. 



