LI. 



RHUS. 



RHUS TOXICODENDRON.* 



Trailing Sumach, Pubescent Poison Oak, Poison Ivy. 



Synonyms. — Rhus radicans, Willd., Sp. PI, vol. i. p. 1481 ; Sort. Kew., vol. 



ii. p. 163 ; Koln, Trav., vol. vi. p. 67. Hedera trifolia virginensis, Park. Theat., 

 6795. Arbor trifolia venenata virginiana folio birsuto, Raii Hist., 795. Edera 

 trifolia canadensis, Cornut. Canada 96, t. 97. Yitis canadensis, Manting, Phyt., 

 p. 239, t. 60. Toxicodendron triphvlluni glabrum, JDuham. Arb. y vol. ii. p. 341, 

 t. 98. Rhus toxicodendron, Linn. Sp. PL, 381 ; Willd., vol. i. p. 1481 ; Sort. 

 Kew. t vol. ii. p. 82; Pursh, Fl. Amer.; Mich., Pot. An. ; Stokes, Pot. Mat. 

 Med. y vol. ii. p. 160; Pot. Mag., vol. xliii. t. 1806. 



Foreign Names. — Fr. : Toxicodendron, Herbe a la Puce, Sumac veneneux 

 Ital. : Rus TossicodeDdro. Germ. : Giftsumacb. Suss. : Greltnik iadovitoi 

 Dut. : Vergiftboom. Swed. : Eorgiftida tradt. 



Nat. Order, Dumosje, Linn.; Terebintace^e, Juss.; Tere- 



binthace^e, De Cand. — Pentandria, Trigynia. 



Spec Cha.e.— Calyx small, five-partite, persistent. Petals five, ovate, 

 spreading. Stamens five, all fertile in the male and hermaphrodite 

 flowers. Ovary one, somewhat globose, one-celled. Styles short, three, 

 or stigmas three, sessile. Drupe almost juiceless, one-celled ; nut bony, 

 perhaps by abortion, one-seeded, and sometimes two or three-seeded. 

 Seed exalbuminous, invested by the funiculus arising from the base of 

 the nut. Cotyledons foliaceous. Radicle incumbent on the upper edge 

 of the cotyledons (De Candolle). 



Spec. Chae. — Rooting. Leaves ternate. Leaflets oval, entire, or sinuate 

 crenate. Racemes on the branches, and axillary, sessile, dioecious. 

 Var. radicans. Stem climbing, and rooting. Leaflets broad, entire, or 

 with scattered teeth. 



Fig. 1. A male stem, with the flowers. 2. The corolla and flower. 3. Cluster 

 of the berries from the female plant. 



* Although Linnaeus, De Candolle, and NuttftQ have made Rhus radicans a 

 different species from Rhus toxicodendron, and have founded the distinction 



