HO ANACARDIACE^E. Rhus. 



the base of the cell. — Shrubs or small trees ; leaves simple or pinnate ; flowers 

 small, polygamous or polygamo-dioecious, in axillary and terminal bracteate pan- 

 icles, or sometimes in racemes or spikes. 



A widely distributed genus of at least 120 species, natives of the warmer extra- tropical regions 

 of both hemispheres, most numerous in S. Africa. There are 14 species in the United States, 

 differing considerably in their characters and so distributed into five sections. The astringent 

 leaves of some species of the section Sumac (not represented in California) are extensively used in 

 tanning, and the resinous juice of others in Japan yields the peculiar well-known lacquer of that 

 country, and the fruit a useful vegetable wax or tallow. 



§ 1. Flowers polygamous or dioecious, in loose axillary panicles : fruit glabrous and 

 whitish ; nut striate: leaves 3-foliolate: juice and effluvium poisonous. — Toxi- 

 codendron. 



1. R. diversiloba, Torr. & Gray. (Poison Oak. Yeara.) Usually somewhat 

 puberulent, the slender shrubby stem erect, or stouter and climbing by rootlets, 3 

 to 8 feet high : leaflets ovate, obovate, or elliptical, 1 to 3 inches long, obtuse or 

 acutish, 3-lobed or coarsely-toothed or sometimes entire, the lobes and teeth obtuse : 

 panicles peduncled : flowers whitish, 1-| lines long : fruit 2 to 3 lines in diameter, 

 somewhat compressed. — El. i. 218; Lindl. Bot. Beg. xxxi, t. 38. R. lobata, 

 Hook. Fl. i. 127, t. 46. 



From Southern California to British Columbia, in this State most abundant in the Coast 

 Ranges. It resembles S. Toxicodendron, Linn., of the Atlantic States, which differs, however, 

 in its acuminate leaflets, sharply toothed or entire, and nearly sessile panicles, usually more dense 

 in fruit. The species are alike very poisonous, causing a severe cutaneous eruption accompanied 

 by intense smarting and itching. The reputed remedies are more numerous than efficacious ; 

 prominent among those in popular use is said to be the bruised leaves or a decoction of the leaves 

 of Grindelia or " Gum-plant." 



§ 2. Flowers polygamo-dioecious, in short sessile scaly-bracted spikes, preceding the 

 leaves: fruit globose, villous, light red; nut smooth: leaves 3foliolate. — 

 Lobadium, Eaf. 



2. R. aromatica, Ait., var. trilobata, Gray. A shrub, 2 to 5 feet high, dif- 

 fusely branched, strongly scented, more or less pubescent, at length nearly glabrous : 

 leaflets sessile, cuneate-obovate or rhomboidal, 1 or 2 inches long, exceeding the 

 petiole, coarsely toothed above and often 3-lobed, the segments obtuse : spikes half 

 an inch long or less, approximate at the ends of the branches : flowers yellowish, a 

 line long : fruit somewhat viscid, 2 or 3 lines in diameter. — Watson, Bot. King 

 Exp. 53. R. trilobata, Nutt. in Torr. & Gray, El. i. 219. 



Throughout the State, ranging to Washington Territory and eastward to the Rocky Mountains 

 and Texas. The typical form of the' Atlantic States has the leaves ordinarily larger and less 

 lobed, and the odor of the plant is perhaps more aromatic. The fruit is said to he pleasantly acid, 

 and is eaten by the Indians : the slender twigs are used in their choicest basket-work. 



§ 3. Flowers polygamous, on bracted piedicels in numerous short dense racemes closely 

 paniculate at the ends of the branches: sepals orbicular, concave, colored: fruit 

 densely pubescent and very viscid, dark red : leaves simple, coriaceous. — 

 Styphonia, Benth. & Hook. (Styphonia, Nutt.) 



3. R. integrifolia, Benth. & Hook. A diffusely branched stout evergreen 

 shrub, 5 to 10 feet high : leaves puberulent when young, soon glabrous, broadly 

 ovate, acute or obtuse, usually entire but sometimes spinosely toothed, 1J to 3 

 inches long, on short stout petioles : flowers rose-colored, in close panicles 1 to 3 

 inches long : petals rounded, ciliate, exceeding the sepals, 1| lines long: fruit ovate, 

 3 lines long. — Gen. PI. i. 419. Styphonia integrifolia, Nutt. in Torr. & Gray, 

 Fl. i. 220 & Sylva, iii. 4, t. 82 ; Torrey. Eacif. E. Eep. vii. 9, t. 2. S. serrata, 

 Nutt. ; Torr. & Gray, Fl. i. 220. 



From Santa Barbara to San Diego, mostly on the coast ; western Arizona, Pahner, Wlieeler. 

 Along the cliffs near the sea it forms close thickets, sometimes on the seaward side presenting a 



