Rhus. ANACARDIACE^. 383 



more entire leaves aud answer to R. mdicans, L. R. verrucosa, Scheele, Linnaia, xxi. 592 

 the niesocarp described for tlie surface of the drupe. Toxicodendron vulyare, jncbescens crena- 

 tiim} volubilis, & serratum. Mill. Diet. ed. 8. (Varieties indiscriminate : a Japanese one coll. 

 Maximoicicz, has hispidulous fruit !) — Moist or shady ground ; Nova Scotia to Florida west 

 to Brit. Columbia, Oregon, and Arizona. (Bermuda, Mex., Japan.) 



R. diversiloba, Tore. & Gray. (Poison Oak, Ybard.) Leaflets oblong or oval or 

 somewliat obovate, with rounded or very obtuse apex, varying from entire to subpinnatifid 

 (1 to 3 inches long); lateral ones subsessile : panicles surpassing the petioles not rarely 

 ecjualling the leaves : otherwise as the preceding. — Fl. i. 218 ; Lindl. Bot. Reg. xxxi. t. 38 • 

 Brew. & Wats. Bot. Calif, i. 110. A', lobata, Hook. Fl. Bor.-Am. i. 127, t. 46, not Poir. 

 R. Toxicodendron, var. diversiloba, Engler, 1. c. 395. — Common throughout California, north 

 to the borders of Washington, where probably it passes into the preceding. 



-I— -i— Leaves pinnate : panicles slender : stems never rooting or climbing. — Varnish 



TREES. 



R. venenata, DC. (Poison Dogwood, Poison Elder, Poison Sumach.) Arborescent 

 shrub, glabrous, or almost so : leaves 7-13-foliolate, with reddish petiole ; leaflets membrana- 

 ceous, oblong or oval, acuminate, entire, acute at base and somewhat petiolulate, pale 

 beneath, 2 or 3 inches long : panicles narrow : drupes small, the stone broader than long, 

 obtusely sulcate longitudinally. — Prodr. ii. 68; Hook. Fl. Bor.-Am. i. 126; Torr. & Gray, 

 Fl. i. 218, 681 ; Emerson, I.e., with plate ;• Engler, 1. c. 397.^ R. Vernix, L. Spec. i. 265,^ 

 except as to syn. Kajmpf., whence however the name (Dill. Elth. t. 292; Pluk. Aim. t. 145, 

 f. 1 ) ; Marsh. Arb. 130 ; Lam. 111. t. 207, f. 2 ; Bigel. Med. Bot. i. 96, t. 10. — Wooded swamps,' 

 Northern New England and Canada to Minnesota, south to Georgia * and W. Louisiana. 



* * Malosma, Nutt. Drupes whitish, very small, smooth ; the mesocarp a thin granular- 

 waxy layer without fibres ; the obscurely didymous stone smooth and bony : leaves simple, 

 thin-coriaceous : flowers polygamous, very numerous in an ample terminal panicle : petals 

 slightly imbricated in the bud : plant apparently innocuous. 



R. laurina, Nutt. Shrub, very leafy, evergreen, exhaling odor of bitter almonds : leaves 

 oblong, verging to lanceolate, entire, acute or obtuse, mucronate, pinuately veiny, 3 or 4 

 inches long, rounded at base, rather long-petioled : flowers very small, white : drupes a line 

 or hardly two lines in diameter. — Nutt. in Torr. & Gray, Fl. i. 219; Brew. & Wats. 1. c. 

 Ill; Engler, I.e. 393. Lithrcea laurina, Walp. Rep. i. 551; Torr. Pacif. R. Rep. iv. 73, 

 & Bot. Mex. Bound. 44, t. 7. — S. California in valleys near the coast, from Santa Barbara 

 to San Diego ^ and islands ; first coll. by Nuttall. 



* * * SiJmac. Drupes red, sour, and the epicarp clothed with acid secreting hairs ; 

 the mesocarp thin fleshy and not ceriferous, its delicate fibres coherent rather with the 

 epicarp and freely separating from the smooth and even stone : no poisonous qualities, 

 except possibly in R. pinnila. — § Sumac in part, & Lobadium (Raf.), DC. Prodr. ii. 67, 72. 

 § TrichocarpcB, Engler, 1. c. 376, excl. R. trichocarpa. 



•1— True Sumachs : leaves pinnately plurifoliolate, deciduous or in one species subpersist- 

 ent, the leaflets sessile ; polygamous (or dioecious) flowers and crimson fruit in a dense 

 and sessile terminal thyrsus or with smaller ones in axils of uppermost leaves ; bracts 

 minute, thin and deciduous : erect shrubs or small trees, with large leaves and stout 

 branches, orange or yellow wood, bark and especially foliage astringent (rich in tannin) 

 and used in tanning ; fl. summer. 



++ Rhachis between the leaflets naked. 



its smaller thicker less pubescent leaflets, — distinctionf? of doubtful value in a plant so near the widely 

 distributed and polymorphous R. Tooncodendron. Similar specimens from W. Florida, Rugel, and 

 Texas, Lindheimer, are in some regards transitions to the typical form. 



1 T. crenntum. Mill. 1. c, probably was R. Canadensis, Marsh. 



'^ Add Millspaugh, Med. PI. i. 37, t. 37. 



3 Add Sargent, 1. c. 23, t. 107, 108. 



* Florida, Riujel. 



5 Also extending far southward into Lower Calif., ace. to Brandegee. 



