I 88 GREENE 



16. RHUS BOREALIS, sp. nov. 



Shrub evidently large but not stout, at least as to the branches, 

 these smooth, glabrous, glaucous : leaves ample as to breadth, 

 but not greatly elongated, 3 dm. long, the usual hairy line of 

 the rachis quite hirsute, but other parts of the rachis, and also 

 the midvein of the leaflets on both faces showing a few pilose 

 hairs ; leaflets 13-17, subsessile, broad and approximate, oblong- 

 lanceolate, 8-1 1 cm. long, subulate-acuminate, coarsely and 

 closely subcrenate-serrate, the serratures about 14 on a side, 

 texture of leaflet uncommonly thin, upper face of a light but 

 rather lurid green, the lower glaucous almost to whiteness : 

 panicle not large, 11 cm. long in fruit, narrow-pyramidal, dis- 

 tinctly pedunculate, the peduncle and branches of panicle hir- 

 sute, the hairiness more or less distinctly retrorse : drupelets 

 larger than the average and of a lighter color, being bright 

 crimson. 



Central Michigan near Alma, on dry ridges, collected Au- 

 gust 12, 1895, by Charles A. Davis, the type specimen in the 

 Herbarium of the Field Museum, Chicago. A fine species, 

 perhaps common enough in central Michigan, and probably 

 beyond the boundaries of the State southward, a region in which 

 little or no effective collecting has been done in late years. But 

 there is a poor flowering specimen, or fragment, in the National 

 Herbarium which, by the one leaf it bears, I can refer here. This 

 appears to have been sent by Mr. Beale, in 1899 ; but there is 

 nothing to indicate who collected it, or where. Although pubes- 

 cent, this bears no relation to R. hirta. 



17. RHUS MEDIA, sp. nov. 



Branches rather sharply angular in maturity and sparsely 

 dotted with small lenticels : leaves large but not elongated, only 

 2 dm. long, rachis not stout, whitish with bloom, glabrous except 

 as to a tomentulose line ; leaflets about 13, large, sessile, oblong 

 or subfalcate-oblong, broadly and abruptly pointed rather than 

 acuminate, appressed-serrate, the serratures 13-15 on a side, 

 the whole leaflet of firm texture and about 8 cm. long, 2-2.5 

 cm. wide, of a dull lightish green above, quite glaucous beneath : 



