386 AXACARDrACE.E. Rhus. 



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

 Turp. Ann. Mus. Par. v. 445, t. 30; Torr. & Gray, 1. c. ; Gray, Gen. 111. ii. 160, t. 100; 

 Engler, 1. c. 385, excl. var. y. Betula triphylla, Tliuub. Diss. Betul. L2, t. 1, f. 2, ace. to 

 Swartzi Aduot. 25.i Turpinia puhescins, & T. (jlahra, Raf. Med. Hep. hex. 2, v. 352, & 

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

 Canada to Minnesota and Saskatcliewan, south to Kentucky and Arkausas,^ past^ing into 

 the following forms. 



Var. ni611is, Gu.w. Leaves and young shoots densely velvety-tomentose, but other- 

 wise as the following. — Gray in Patterson, Ciieck-list, 1892,' 21. R. trilohala, var. (molliter 

 tomcnlosa), (iray, PI. Wright', ii. 27. R. trilobata, var. pilosissima, Engler, 1. c. 386.— New 

 Mexico.-' &c., Ffiudler, Wri(/ht, &c. 



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

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

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

 Jour. Sci. ser. 2, xxxiii. 408 ; Wats. Bot. King Exp. 53 ; Brew. & Wats. Bot. Calif, i. 110. 

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

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

 to Texas,* and west to California and Oregon. 



Var.* Simplicifolia, Gukkxe. I>ike tlie last, but leaves all or mainly simple, round- 

 cordate, crenatc-lobnlate or some deeply 3-cleft. — Bull. Torr. Club, xvii. 13.— Canons of 

 N. Arizona, (Jreene ; Cautilla.s Mountains, on the borders of Lower California, Orctttt. 



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

 ments a])proacliing in size the crenate or incised lateral leaflets, thus rendering the leaves 

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

 R. microph^ila, Engelm. Tall shrub with verrucose branches, puberulent or glabrous : 

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

 long, entire, veinless, sometimes silky-pubescent beneath, not shining ; rhacliis winged be- 

 twe'en 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 ; Engler, 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 ceifferous. 

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

 of slender branchlets, deciduous ; leaflets 9 to 1 7, subcoriaceous, oblong, obtuse, very unequal- 

 sided, mucronate, somewhat shining above, ol)Scurely 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 (calvx and bracts deciduous), globular, with thin epicarp and rnesocarp (the latter 

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

 drupe rather of .Srhinus, but the .stone and insertion of seed as in Rhu.% and foliage, &c. not 

 unlike R. microphylla.) — Gray in Patterson, Check-li.st, 1892, 21. Pistacia ^fexicana, HBK. 

 Nov. Gen. & Spec. vii. 22, t. 6"o8 ; Torr. Bot. Mex. Bound. 44. — S. W. Texas, on the Rio 

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



1 Add pyn. LnhniVntm amentaceum, Raf. Am. Monthly Mag. iv. (1819), 358. 

 3 Florida, Chapman. 



S Also in Arizona on the Gila River, Rushy, and at Ft. Verde, Meams. 



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

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



