6 FOSSIL FLORA OF THE SIERRA NEVADA. 



current; the areolation obsolete, the surface coarse, the substance not thick, 

 rather membranaceous. 



This species has not any marked relation with any fossil one. By the 

 nervation, and somewhat also by the form of the leaves, it is allied to 

 Q. castanea, Willd., of the present flora of North America, but still more 

 to a section of Mexican Oaks, whose coriaceous leaves are bordered with 

 short distant teeth : Q. Ilumboldli, Q. glaucescens, Humb. and Bonpl., Q. 

 spicata, Kunth., etc. 



Habitat. — Chalk Bluffs. Voy's Collection. 



Quercus Boweniana, sp. nov. 



PI II. Figs. 5, 6. 



Leaves coriaceous, rather small, oblong, lanceolate, pointed or acuminate, gradually curv- 

 ing to a short petiole ; borders obscurely and distantly dentate; secondary veins 

 parallel, simple, craspedodrome. 



The smallest of the two leaves which represent this species is five cen- 

 timeters long, comprising the short petiole, and one and a half centimeters 

 broad; the other is about twice as large; their form is elliptical oblong, 

 narrowed in the same degree toward the point or short acumen (broken), 

 and to the petiole, which is scarcely two millimeters long, and slightly 

 inflated. The borders, distantly and obscurely dentate, are entered by 

 the points of the secondary veins, which are simple, equidistant, parallel, 

 more or less open, according to the size of the leaves, straight or curv- 

 ing very little in passing to the borders. The areolation, observable only 

 upon the fragment of the larger leaf, is formed by subdivisions, generally 

 in right angle of the fibrillar, and composed of very small quadrangular 

 meshes. 



These leaves have a distant relation to those of the following species, 

 but none known as yet to any from the European Tertiary. 



Habitat. — Bowen's Claim. Voy's Collection. 



Quercus distincta, sp. nov. 



PI. II. Figs. 7-9. 



Leaves somewhat thick, or sitbcoriaceoics, of larger sizt than those of the former species, 

 long petioled, ovate, rounded to the petiole and entire toward the base, distantly 

 obscurity dentati above, gradually narrowed to an obtuse point ; secondary veins 

 distant, subcamptodrome. 



