32 FOSSIL FLORA OF THE SIEEEA NEVADA. 



relation as li. typhinoides bears to It. typhina. The shape of the leaves 

 is like that of the specimens from Cuba, whose nervation is, however, 

 more oblique to the midrib. The specimens of the cultivated plants of 

 the species which I have obtained in great number and finely preserved 

 from Key West, show in the direction of the secondary nerves in the 

 intermediate veins, in their anastomoses by veinlets of d liferent direction, 

 in the multiple bows along the borders, the same characters as in these 

 fossil leaves, whose nervation is equally very varied. Sometimes the 

 secondary nerves pass to the borders, and enter them mostly by branch- 

 lets, and the tertiary parallel veins always irregular, variously distant, join 

 them by nervilles, either oblicpie or in right angle, composing a series 

 of simple secondary bows, distant from the borders, to which they are 

 united also by nervilles. Sometimes the secondary nerves curve in large 

 bows at a greater distance from the borders, as in Fig. 13, and with ner- 

 villes in right angle upon their backs compose a second row of festoons 

 which follow close to the margins. In Fit! - . 12 the details of nervation 

 are less varied, and more closely resemble those of the living species. 

 The leaflets from Cuban specimens are cpiite as unequilateral as those of 

 this fossil species. Those of Florida are more regular, generally round 

 truncate, and equilateral. The leaves are indifferently three palmately 

 divided or imparip innate. By the nervation, Cclastrus Zacchariemis, Sap., 

 of the Miocene of France (St. Zaccharie), is related to this. Its leaves, 

 however, are dentate or crenate. 



Habitat. — Table Mountain, Tuolumne County, California. Voy's Col- 

 lection. 



Rhus dispersa, sp. nov. 

 PI. I. Ftg. 23. 



Leaflet small, subcoriaceous, Ungulate, cuneate t<> an obtuse point, rounded, subcordate at 

 the base; borders denticulate from the middh, upwards; nervation stibcamptodrome. 



This leaflet, of a very small size, one and a half centimeters long, and 

 scarcely seven millimeters broad, is evidently detached from a compound 

 leaf. Slightly and gradually enlarged upwards from the base, it is rap- 

 idly narrowed at the top into an obtuse point, and distinctly though dis- 

 tantly denticulate in its upper part. The secondary veins, mostly oppo- 

 site, irregular in distance, but parallel, go out from the narrow midrib in 

 an open angle of divergence, 50° to 60°, pass straight to very near the 



