386 ANACARDIACE^. Rhus. 



veolens (the more glabrous form), Ait. Kew. i. 367, 368. R. aromaticct, Michx. Fl. i. 184; 

 Turp. Aim. Mus. Tar. v. 44.5, t. 30; Torr. & Gray, 1. c. ; Gray, Geu. 111. ii. 160, t. 160; 

 Eugler, 1. c. 385, excl. var. y. Betula triphylla, Thuub. Diss. Betul. 12, t. 1, f. 2, ace. to 

 Swartz, Adiiot. 25.1 7\trpinia pubescens, & T. glabra, Raf. Med. Kep. liex. 2, v. 352, & 

 Desv. Jour. Bot. ii. 170 (1809). — Dry rocky banks, N. W. New England and adjacent 

 Canada to Minnesota and Saskatchewan, south to Kentucky and Arkausas,^ passing into 

 the following forms. 



Var. mollis, Gray. Leaves and young shoots densely velvety -tomentose, but other- 

 wise as the following. — Gray in Patterson, Check-list, 1892, 21. R. trilobuta, var. (molliter 

 tomentosa), Gray, PI. Wright, ii. 27. R. trilobata, var. pilosissima, Engler, 1. c. 386. — New 

 Mexico,^ &c., Fendler, Wric/ht, &c. 



Var. trilobata, Gray. Glabrous or early glabrate : leaves smaller ; leaflets usually 

 half inch to incli loug, obovate-cuneate, crenately few-lobed or incised, mainly at summit. — 

 Gray in Coulter, Contrib. U. S. Nat. Herb. ii. 68. R. aromatica, var. trilobata, Gray, Am. 

 Jour. Sci. ser. 2, xxxiii. 408 ; Wats. Bot. King Exp. 53 ; Brew. & Wats. Bot. Calif, i. llO. 

 R. trilobata, Nutt. in Torr. & Gray, Fl. i. 219; Gray, PI. Lindh. pt. 2, 159, PI. Wright, i. 31, 

 ii. 27, &c. R. trilobata, var. glaherrima, Engelm. 1. c. — Rocky bluffs and poor soil, Dakota 

 to Texas,* and west to California and Oregon. 



Var.* simplicifolia, Greene. Like the last, but leaves all or mainly simple, round- 

 cordate, crenate-lobulate or some deeply 3-cleft. — Bull. Torr. Club, xvii. 13. — Carions of 

 N. Arizona, Greene ; Cantillas Mountains, on the borders of Lower California, Orctitt. 



Var.* quinata, Jepson (under R. trilobata). Terminal leaflet deeply 3-fid, the seg- 

 ments approaching in size the crenate or incised lateral leaflets, thus rendering the leaves 

 apparently 5-foliolate. — Erythea, i. 141. — Napa Co., Calif., Jepson. 



R. microph^lla, Engelm. Tall shrub with verrucosa branches, puberulent or glabrous : 

 leaves subcoriaceous, pinnately 7-9-foliolate ; leaflets a quarter to barely half inch long, ob- 

 long, entire, veinless, sometimes silky-pubescent beneath, not sliiiiing ; rhachis winged be- 

 tween the pairs : flowers white, small, in heads or oblong spikes : fruit nearly of the preceding. 

 — Engelm. in Gray, PI. Wright, i. 31, & ii. 27; Torr. Bot. Mex. Bound. 44 ; P:ngler, 1. c. 

 387. — Margin of thickets and rocky hills, S. & W. Texas to S. Arizona, Wright, Lindheimer, 

 Reverchon. (Mex., Schaffner, Palmer, Pringle, &c.) 



* * * * PiSTACiofDES. Drupes glabrous and with smooth even stone ; aromatic pulp 

 neither acid nor ceriferous. 



R. Mexicana, Gray. Shrub or small tree, glabrous (in age) : leaves crowded at summit 

 of slender branchlets, deciduous ; leaflets 9 to 17, subcoriaceous, oblong, obtuse, very unequal- 

 sided, mucronate, somewhat shining above, obscurely veined (half inch or more long) : 

 rhachis narrowly margined : panicles axillary, much shorter than the leaves : flowers and 

 bracts unknown : drupes spicately sessile or subsessile on the few branches of the panicle, 

 naked (calyx and bracts deciduous), globular, with thin epicarp and rnesocarp (the latter 

 said to be resinous), not fibrous, adherent to the lenticular thin-osseous stone. (Taste of 

 drupe rather of Schinits, but the stone and insertion of seed as in Rhus, and foliage, &c. not 

 unlike R. microjihylla.) — Gray in Patterson, Check-list, 1892, 21. Pistacia Mexicana, IIBK. 

 Nov. Gen. & Spec. vii. 22, t. 608 ; Torr. Bot. Mex. Bound. 44. — S. W. Texas, on the Rio 

 Grande, Bigelow. (Mex. in northern parts, Gregg, Parrg, and Palmer.) 



1 Add syn. LohncVnim amentaceum, Raf. Am. Monthly Mag. iv. (1819), 358. 



2 Florida, Chapman. ^ 

 8 Also in Arizona on the Gila River, Rushy, and at Ft. Verde, Mearns. 



* Nebraska, Clements, Rydberg ; Kansas, Shear, Dnrman ; Ft. Towson, Arkansas, Dr. Edwards; 

 Georgia, Small ; also northward into Brit. America, Assiniboia, Alberta, Macoun. 



