RHUS. XXXIIJ. ANACARDIACEJE. 203 



2. R. TVPHlNA. Stag-horn Sumach. 



Branches and petioles "densely villous ; Ifts. 615 pairs, oblong-lanceolate, 

 acuminate, acutely serrate, pubescent beneath; fr. red, with crimson hairs. 

 A larger shrub than the former, attaining the height of 20f, in rocky or low 

 barren places, U. S. and Can. Stem with straggling, thick branches. Leaves 

 at length 2 3f long. Leaflets 2 4' long, J as wide, sessile, except the termi- 

 nal odd one. Flowers in terminal, thyrsoid, dense panicles, yellowish-green, 

 often 9 $ or Q J* . Drupes compressed, compact, the crimson down very 

 acid. Jn. The wood is aromatic, of a sulphur-yellow, and used in dyeing. 



0. laciniata. Lfts. very irregularly coherent and incised ; 'panicles partly 

 transformed into gashed leaves. Hanover, N. H. Rickard. 



3. R. copALLlNA. Mountain Sumac. 



Branches and petioles pubescent; Ifts. 4 10 pairs, oval-lanceolate, mostly 

 entire, unequal at base, common petiole winged; fis. in dense panicles; drupes 

 red, hairy. A smaller shrub, not half the height of the last, in dry, rocky pla- 

 ces, U. S. and Can. Common petiole about 6' long, expanding into a leafy 

 margin, between each pair of leaflets. Leaflets 1 3' long, near as wide, 

 dark green and shining on the upper surface. Panicles of flowers terminal, 

 sessile, thyrsoid, 9 cT> greenish Drupes acid. Jl. . 

 ft. leaflets coarsely and unequally serrate. N. Y. Barratt. 



4. R. VENENATA. DC. (R. vernix. Linn.') Poison Sumac. Dog-wood. 

 Very glabrous ; Ifts. 3 6 pairs, oval, abruptly acuminate, very entire ; 



panicles loose, pedunculate ; drupes greenish-yellow, smooth. A shrub or small 

 tree of fine appearance, 10 15f high, in swamps, U. S. and Can. Trunk seve- 

 ral inches diam., with spreading branches above. Petioles wingless, red, 6 10' 

 long. Leaflets about 3' long, nearly as wide, sessile, except the odd one. 

 Panicles axillary, 9 <?, those of the barren tree more diffuse. Flowers very 

 small, green. Drupes as large as peas. Jn. The whole plant is very poison- 

 ous to the taste or touch, and even taints the air to some distance around with 

 its pernicious effluvium. 



* * Leaves ternate. 



5. R. TOXICODENDRON. Poison Oalc. Poison Ivy. 



Erect or decumbent ; Ivs. pubescent ; Ifts. broadly oval, acuminate, entire 

 or sinuate-dentate ; fls. in racemose, axillary, subsessile panicles ; drupes smooth, 

 roundish. Can. and U. S. A small shrub, 1 3f high, nearly smooth in all 

 its parts. Leaflets 2 6' long, f as wide, petiolate, the common petiole 45' 

 long. Flowers small, 9 c?- Drupes pale brown. Poisonous, but less so than 

 the last. 



0. radicans. Torr. (R. radicans. Linn, and of 1st edit.) Poison Ivy. St. 

 climbing 3 20 or 50f ! by myriads of radicating tendrils. It seems now gen- 

 erally conceded that this is but a variety. Certainly, if so, it is a very remark- 

 able one. In damp, shady places. Poisonous. 



6. R. AROMATICA. Ait. Sweet Sumac. 



Lfts. sessile, incisely crenate, pubescent beneath, lateral ones ovate, ter- 

 minal one rhomboid; fls. in close aments, preceding the leaves; drupe globose, 

 villous. A small, aromatic shrub, 2 6f high, in hedges and thickets, Can. and 

 U. S. Leaflets 1 2' long, } as wide, sessile, the common petiole an inch or 

 two in length. Flowers yellowish, with a 5-lobed, glandular disk. Drupes 

 red, acid. May. 



* * * Leaves simple. 



7. R. CorlNus. Venetian Sumac. Lvs. obovate, entire ; fls. mostly abor- 

 tive ; pedicels finally elongated and clothed with long hairs. A small shrub, 6f 

 high, native in Ark. according to Nuttall, remarkable chiefly for the very sin- 

 gular and ornamental appearance of its long, diffuse, feathery fruil-stalks, 

 showing in the distance as if the plant were enveloped in a cloud of smoke. 

 Flowers small, in terminal, compound panicles. Leaves smooth, entire, much 

 rounded at the end. In Italy the plant is used for tanning. + 



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