DESCRIPTIONS OF SPECIES. 127 



tified. The original tracing of Mr. Meek, on which Professor Heer wrote 

 the name given to the leaf, as well as the original, are before me as I write, 

 so there can be no mistake about the identification of the species. I have 

 seen no other specimens than this one, and have nothing to add to the descrip- 

 tion given by Professor Heer, except that the emargination of the summit 

 is in part at least the result of fracture and may not be a constant character. 

 The peculiar crowded nervation will serve to distinguish this leaf from the 

 others described by Professor Heer and noticed elsewhere (Leguminosites 

 Marcouanus and Pkyllites obcordatus), both of which have similar obovate 

 outlines and emarginate summits. 



Formation and locality: Cretaceous (Dakota group). Blackbird Hill, 

 Nebraska. 



Order OLEACEiE. 



Fraxinus affinis Newb. 

 PI. XLIX, fig. 5. 

 Proc. U. S. Nat. Mus., Vol. V (March 21, 1883), p. 510. 



"Leaves petioled, lanceolate, long-pointed, attenuate at base; margins 

 coarsely and irregularly toothed at and above the middle." 



Collected by Rev. Thomas Condon. 



This leaf has almost precisely the form, serration, and nervation of 

 some folioles of F. Americana now living, but it is narrower and has a more 

 crowded nervation than the average leaflets of that species. 



Among fossil ashes this approaches closely to F. excelsifolia Webb. 

 (Palseontogr. IV, p. 150, PI. XXVII, fig. 3), but the dentation in that sne- 

 cies is much coarser and the nervation more remote. 



Professor Heer has described two species of Fraxinus (F. predicta and 

 F. denticulata) , both of which Lesquereux thinks he has identified among 

 the Tertiary leaf impressions obtained from the West. The fragments he 

 figures, however, are too imperfect for the identification of the species. 

 They are both described by Professor Heer as sessile, while the leaf before 

 us is distinctly petioled. 



Formation and locality: Tertiary (Miocene). Bridge Creek, Oregon 



