218 ANACARDIACE.E. Rhos. 



In barren places, Canada ! to Florida! and west to Arkansas! /?. High- 

 lands of the Hudson River, Dr. Barrati! Mountains of Pennsylvania, Dr. 

 Darlington. Red River, Louisiana, Dr. Hale! y. Tampa Bay, Florida, 

 Dr. Burrows ! July-Aug. — Stem 3-8 feet high, branched ; juice resinous. 

 Veins of the upper surfaci; of the leaves pubescent. Wing of the pe- 

 tiole usually broad, interrupted at the leaflets. Peduncles downy. Drupes 

 small, compressed, acid. 



-w^^5. R. venenata (DC.) : glabrous; leaflets 7-13 (membranaceous), obovate- 

 oblong, entire, abruptly acuminate ; panicles slender, in the axils of the up- 

 permost leaves; drupes subglobose, smooth, greenish-white. — DC. prodr. 2. 

 p. 68 ; Berk, bot. p. 76; Hook. I. c. ; Darlingt. f. Cest. ed. 2. p. 207. R. 

 Vernix, Linn, (in part) ; Michx. ! Ji. 1. p. 183 ; Ell. I. c. ; Bi^el. med. bot. 

 1. p. 96. t. 10. 



In swamps, Canada and Northern States ! to Georgia ! west to Alexandria, 

 Louisiana, Dr. Hale ! June. — A shrub, 8-15 feet high, very poisonous to 

 the touch with most persons. Leaves often slightly pubescent beneath. Flow- 

 ers greenish, mostly dioecious, small. Drupe as large as a pea : nut broad- 

 er than long, compressed, lidged. Cotyledons oval, rather thick and fleshy. — 

 The juice of this shrub is a varnish, like that of the Japanese plant (R. 

 vernicifera, DC. I. c), from which it has only recently been distinguished. 

 (See Bigel. I. c.) — Poison Sumach, Poison Elder, &c. i, •. \ i-, / ^-^ 



^<^6. R. Toxicodendron (Linn.) : stem erect, decumbent, or climbing by ra- 

 'dicles ; leaves 3-foholate, somewhat pubescent; leaflets (membranaceous) 

 broadly oval or rhomboid, acuminate, entire or toothed, the lateral ones ine- 

 quilateral ; panicles racemed, axillary, subsessile; drupes subglobose, smooth. 

 —Michx.! ji. 1. p. 183; Torr.! ji. 1. p. 323. R. Toxicodendron & radi- 

 cans, Lin7i. ; Nutt. ; DC.^c. 



a. not climbing ; leaves entire, or variously and irregularly sinuate-toothed 

 or lobed. — R. Toxicodendron, Linn. ; Nutt. ^c. R. Toxicodendron ji. quer- 

 cifolium, Michx. I. c. 



p. chmbing ; leaves more commonly entire or nearly so. — R. radicans, 

 Linn. ; Bot. mag. t. 1806 ; Bigel. med. bot. 3. p. 19, t. 42 ; DC. I. c. R. 

 Toxicodendron a. vulgare, Michx. I. c. R. Toxicodendron 0. radicans, 

 Torr. ! ft. I. c. 



/.leaves oval-oblong; fruit smaller. — R. Toxicodendron >'. microcarpon, 

 Michx. I. c. 



In rather shady usually damp places, Canada ! (on the Saskatchawan, 

 Hooker) to Georgia ! west to Arkansas ! & the Rocky Mountains ! N. W. 

 America, Z)o?fo-/flrs (ex Hooker). May-June. — A low shrub, or climbing ; 

 poisonous like' the preceding. Leaflets large, petiolulate. Flowers mostly 

 dioecious, greenish. Drupes nearly the size of the preceding, pale chestnut- 

 color. — Poison-Ivy, Poison-Oak, ^c. 



J 7. R. diversiloba: nearly glabrous; stem scarcely climbing, with short 

 leafy branches; leaves 3- (rarely 5-) foliolate; leaflets very obtuse, in the pis- 

 tillate plant slightly, in the staminate rather deeply pinnately lobed; lobes 

 very obtuse, the incisions acute ; panicles axillary, racemose ; drupes subglo- 

 bose. — R. lobata, Hook. ji. Bor.-Am. 1. p. 127, t. 46, <^ in bot. Beechey, p. 

 137 (the male), not of Poir. R. Toxicodendron, Hook. ^ Am. in bot. 

 Beechey, I. c. (the pistillate plant) ? 



Borders of woods &c., Oregon. Douglas, Nnltall! & California, Beechey, 

 Nuttall! — "The sterile and fertile flowers in this species (which is very 

 near R. Toxicodendron) present some notable diflferences. The sterile, which 

 is figured by Hooker, has rather deeply lobed leaflets, sometimes in fives, 

 and larger flowers: in the fertile the leaflets are almost entire or slightly 

 lobed and the flowers considerably smaller, so that it might readily be taken 

 for a distinct species. The fruit is white, somewhat pubescent and gibbous." 

 Nutt. — The panicles are often shorter than the petioles. 



