A STUDY OF RHUS GLABRA 1 75 



* * Leaves ample (except in No. 25), of a lighter green above, 



less glaucous beneath. Panicles in almost all pyramidal. 

 All the species far western and northwestern. 

 Leaflets 13-17, subsessile, sparsely pilose, subulate-acuminate. 



16. J\ . borealis. 

 Leaflets 1 1— 1 3. 



Large, sessile, subfalcate-oblong, abruptly broad-pointed. 



17. R. media . 



Oblong, subsessile, abruptly acuminate iS. R . cismontana. 



Large, acutish at base and subpetiolulate, abruptly short-pointed. 



19. R. sambucina. 

 Leaflets 13-17- 



Shining above, sessile by an obtuse base, cuspidately acute. 



20. R. miens. 

 Checkered light and dark green above, subsessile, cuspidatelv acu- 

 minate 21. R. tcsscllata . 



Leaflets 9-15, oblong-lanceolate, sessile, acuminate. 



22. R. macrotkyrsa. 

 Leaflets 17-19, oblong-linear, sessile, acutish at base, long-acuminate. 



23. R. arguta. 

 Leaflets 13-17, oblong, sessile, obtuse at base, the apex merely acute. 



24. R. aprica. 

 Leaflets 11-13, narrowly lanceolate, sessile, acuminate. 



25. R. occidentalis . 



* * * Leaves smaller, of fewer leaflets, altogether pale, very glau- 



cous beneath. Panicles small, less definitely pyramidal. 

 All of arid southwestern regions (But Xo. 9. A'. pnl- 

 chclla, of the southern Appalachian mountains is naturally 

 of this group). 

 Leaflets 1 1-15. 



Sessile, oblong-lanceolate, short-acuminate 26. R. albida. 



Petiolulate, subfalcate-lanceolate, slenderly acuminate. 



27. R. elegant id a. 



Leaflets 9—1 1 , sessile, oval to oblong-lanceolate 2S. R. sorbifolia. 



Leaflets 7-9, subsessile, lanceolate, slenderly acuminate deeply incise- 

 serfate 29. R. asplenifolia. 



1. RHUS GLABRA Linnaeus. 

 Rhus rami's ex stipitc -pullulantibus giabn's, Banist. Catal. in 



Ray, Hist. 2 : p. 1928. 1688. 

 Rhus Virginicum panicula sparsa, rami's patulis glahris, 



Dillen., Hort. Elth. p. 323, t. 314. 1732. 



