KNOWLTON. 



BIOLOGICAL CONSIDERATIONS. 



93 



The followiuo' table shows at a ghmce the number of forms found 

 at each of the localities: 



Tdhli' xlioinn.ij tlic niimhcr (if fornix nf cdch lura/lti/. 



Currant C'reek 3 



Cherry Creek 20 



Bridge Creek 46 



One and one-half miles east oi Clarn<jH Ferry 3 



Three miles above Clarnos Ferry 2 



One and one-half miles northeast of Fossil 3 



Three and one-half miles south of Lone Rock 4 



Van Horn's raneh and vicinity 80 



Officer's ranch 3 



From this it appears that three localities — namely, Cherry Creek, 

 Bridge Creek, and Van Horn's ranch and vicinity — afi'ord over 90 per 

 cent of the entire flora. 



BIOLOGICAL CONSIDERATIONS. 



As alread}' pointed out, the present woody flora of the John Day 

 Basin is inconsiderable, consisting of pines along the higher ridges, 

 occasional junipers along the lower ridges, and a scant fringe of cotton- 

 woods and willows along the streams. At best not more than three 

 families are represented. The fossil flora, on the other hand, is a rel- 

 atively rich one, and shows especially a great variety of woody plants. 

 Following is a complete list of families represented: 



Schizicacete. Ulmacese. Celastracea?. 



PolypodiacejB. INIoracefe. Acerace;e. 



Equisetacefe. Berberidaceie. Hippocastanacese. 



Ginkgoaceas. Magnoliaceee. Sapindacete. 



Pinace;e. Lauracea?. Rhamnaceae. 



Graminefe. Hydrangeacea^ Tiliacese. 



Cyperacese. Hamamelidacete. Araliacese. 



Smilaceis. Platanace*. Cornacese. 



Salicace;e. Rosacefe. Ericaceae. 



Myrieaceae. Mimosacea^. Ebenaceae, 



Juglandaceae. Ca?salpinaceie? Oleaceae. 



Betulaceae. Simarubacese. 



Fagaceaj. Anacardiacege. 



The ferns, judging from the remains, must have played a very 

 inconspicuous role in the Tertiary flora of this region. Two families 

 and only four species are represented, and these are confined to a sin- 

 gle horizon. They are also few in individuals, Lvgodium being the 

 most aljundant. 



Associated in the same beds with the ferns are a large number of 

 individuals of an Equisetum, all of which have l)een referred to a sin- 

 gle species {jK. ore(jo)ieftise Newb.). The confused character of the 

 matrix gives no indication of the height to which this species grew, 

 but it must have been conspicuous, for it is not uncommon to find 



