OF ARKANSAS. 319 



for fossil leaves, which could be found only by opening the clay-banks 

 overlying the lignites. But they were taken from the chalk-banks of the 

 Mississippi and from the red shales of Tennessee, of which the position is 

 apparently a little superior to the place generally occupied by the beds of 

 lignite and certainly of the same age. 



DESCRIPTION OF FOSSIL LEAVES OF THE TERTIARY. 



1. Magnolia Hilgardiana, Sp. nov. (PL 6, fig. 1). Apparently a leaf of a 

 new species of the beautiful genus Magnolia. It has a great likeness to 

 Magnolia tripetala, Michx. (the umbrella-tree), but is rounded and not 

 pointed at its base. The nerves marked on the figure are a little broader 

 than on the specimen. The primary and secondary nerves are strong and 

 distinct, much curved upwards near the margin of the leaves. The ter- 

 tiary veinlets are obsolete, at least on the specimens figured here, but from 

 other specimens appear nearly straight and perpendicular to the secondary 

 veins. The margin of the leaves and their surface is undulated. The spe- 

 cimens were communicated by Prof. Eug. AY. Hilgard, to whom this species 

 is dedicated. 



2. Rhamnus marginatus, Sp. nov. (PI. 6, fig. 2). This leaf, from various 

 broken specimens of the same species, appears to have been generally oval- 

 lanceolate, somewhat obtuse, and entire. The nervation is distinct. Pri- 

 mary and secondary nerves broad and thick, tertiary veinlets perpendicular 

 to the secondary veins and about continuous. The secondary veins curving 

 upwards and running up along the borders give to the leaf the appearance 

 of being marginated. It is related to Rhamnus Carolinianus (Walt.), (the 

 Carolina buckthorn), a common species in Arkansas. The fossil plant is 

 found in the red shales of Tennessee and also, apparently at least, in the 

 chalk-banks of Columbus, Kentucky. 



3. Quercus Saffordii, Sp. nov. (PL 6, fig. 3). A very fine species of oak 

 which, as far as I know, has no relation with any species now living on the 

 continent of America. The leaves are nearly linear, from four to six inches 

 long, taper pointed, with the margins cut by sharp, regular, distant teeth 

 to near the base, where they are narrowed in a short petiole. The medial 

 nerve is broad and flat ; the secondary nerves are of two kinds ; long and 

 running to the points of the teeth ; or intermediate to them and shorter. 

 This species was found and communicated by Prof. James M. Safford, 

 State Geologist of Tennessee, whose name it bears. 



