Rhus. TK1!KI;IXTHIXE.E. 29 



TEREBINTHINEjE. 



RHUS, Linn. 



Rhus typkinoides, sp. nov. 



PI. IX. Figs. 1-6. 



Leaves pinnate, leaflets opposite, distant, small, short-petioled, lanceolate, acutely taper- 

 pointed or acuminate; borders serrate; secondary veins numerous, parallel, at an 

 iijirn angle of divergence, camptodrome. 



It .seems at first as if these leaves, which are represented by numerous 

 specimens, might be referable to two different species, one with unequi- 

 lateral leaflets, the other with more equal ones gradually narrowed to 

 the petiole, as Figs. 1 and 5. The difference is evidently the result of 

 the lateral or terminal position of the leaflets, as distinctly seen from the 

 lower fragment of Fig. 1. The nervation is the same, and the denticu- 

 lation of the borders is merely more or less enlarged, according to the 

 size of the leaflets. It is easy to recognize the close affinity of the fossil 

 species to Rhus t/jphiua, Linn., the staghorn Sumach, so frequently seen 

 on the eastern slope of North America. There is a difference, however, 

 in the generally longer linear leaflets of the living species, in the more 

 marked or larger denticulations of the borders, and in the more open 

 angle of divergence of the lateral veins, which are less regularly camp- 

 todrome, more generally entering the teeth by their points than by 

 branching veinlets. I find, however, among the specimens of R. typhina 

 some leaflets where these deviations or differences are scarcely notice- 

 able. The consistence of the fossil leaflets, though not coriaceous, is firm, 

 somewhat thick. In the fossil species of Rhus this one is comparable to 

 R. oblita, Sap., and R. dcrclicia, Sap., both of the Miocene of France, com- 

 pared by the author to Rhus typhina, to which, however, they are less 

 intimately allied than ours. 



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

 lection. 



Rhus Boweniana, sp. nov. 



PI IX. Figs. 8, 9. 



Leaves pinnate ; leaflets unequilateral, oblong-oval, obtusely pointed ; secondary veins 

 numerous, pa rail I ; borders distantly obscurely denticulate. 



