12 FOSSIL FLORA OF THE SIERRA NEVADA. 



the lower part of Fig. 5 is only half the length of that of the leaf, as 

 it is also in the specimens figured by Heer. The larger leaves are seven, 

 palmately nerved, the lowest veins open and thin, mere marginal vein- 

 lets; the middle ones of an intermediate size and divergence, the upper 

 ones ascending in an acute angle of divergence to at least the three 

 fourths of the laminas, either inclining toward the borders, or toward the 

 midrib, which they nearly equal in size, and always branching outside ; 

 the secondary veins are few, and at a distance from the primary ones. 

 As marked in Fig. 2, the areolation is formed by division of the nervilles 

 in right angle, forming large subquadrate meshes, which, subdivided in the 

 same direction by thinner veinlets, result in a very small ultimate irreg- 

 ularly quadrate reticulation. The various forms represented upon our 

 plate are identical with those of the Baltic Mioc. Fl., Pis. V. and VI., 

 agreeing equally well with those of the specimens from Greenland, Spits- 

 bergen, and Alaska. 



This species seems especially a representative of the Upper Miocene. 

 We have it from the Green River group of the Rocky Mountains, but 

 it has not been seen at Carbon, or in any other station of the American 

 Lignitic. 



Habitat. — Chalk Bluffs, California. Professor J. D. Whitney's, and Voy's 

 Collections. Fig. 6 is marked Roach Hill, Oregon. 



PLATANUS, Linn. 



Platanus appendiculata, sp. nov. 



Pi III Fiys. 1-6. PI. VI Fir,, lb. 



Learcs tncmbranamnts or sulirorioccoits, rariablt in size, either very large, widening up- 

 wards, fan-like, abruptly curving and decurring to the petiole; or smaller, broadly 

 obovate, rounded or subtruncate to a short point, wedge-form to the base, distantly 

 dentate by short fat teeth ; stipules double, leaf-like at the bum of the short petiole. 



These remarkably fine leaves seem at first to represent two species, 

 the one, Fig. 1, with very large, fan-like leaves, rapidly narrowed down- 

 ward, and decurrent to the petiole, truncate or rounded at the top, with 

 the borders marked by distant short teeth, separated by nearly flat or 

 concave sinuses. This leaf, the only one seen of this size, is at least 

 twenty-three centimeters long, twenty-four centimeters broad in its upper 

 part, with a very long thick midrib, four millimeters broad at the base. 



