THE MIOCENE OF EUROPE, ASIA, AND NORTH AMERICA 291 



and the sedges (Cyperacea?) only a single doubtful form has been found. 

 The conifers, although represented by several genera, must also have played 

 an inconspicuous role. Of the deciduous types, the birches (Betulaceae) 

 were most abundant; next in importance were the beeches (Fagaceae), and 

 then the maples (Aceracese), which attained a great size in the Mascal'l 



Fig. 144. — Contemporary Middle Miocene mammals of the western plains region to same 

 scale (X ^^). By Charles R. Knight. A. Oxydactylus, primitive giraffe camel. B. Meryco- 

 dus, ancestral horned ruminant. C. Pronomotherium, aquatic oreodont with proboscis. 

 D. Thinohyus, ancestral peccary. E. Epigaulus, horned burrowing rodent. 



beds. We observe also walnuts, plane trees, willows, and sweet gums, the 

 latter {Liquidambar) forming a conspicuous element. Dr. Arthur Hollick* 

 observes of this flora of central Oregon in Middle Miocene times that it 

 points to a temperate climate, the breadfruit (Artocarpus) alone indicating 

 warmer conditions, although both this form and the alleged cinnamon 

 (Cinnamomum) are not certainly identified. The climate was probably 

 south temperate. 



* Notes by Dr. Hollick, March, 1909. 



