ANACARDIACE^E. 75 



indehiscent, usually drupaceous. Seed without albumen ; 

 radicle superior or inferior, next the hilum ; cotyledons thick 

 and fleshy or leafy. 



Trees or shrubs, with a resinous, gummy, caustic, or even 

 milky juice. Leaves alternate, .not dotted. 



1. RHUS. Linn. 



Calyx small, 5-parted, persistent. Petals 5, ovate, spread- 

 ing. Stamens 5. Styles 3, ' short, or 3 sessile stigmas. 

 Drupe nearly dry, with one bony seed. 



Pentandria. Trigynia. 



* Leaves ternate. 



1. R. toxicodendron Linn.: stem erect, pubescent near the summit ; 

 saves ternate ; leafets broad, oval, entire, sinuate or lobed, subpubes- 



~ent beneath ; flowers dioecious, in sessile axillary racemes. R. toxi- 

 codendron, var. qucrctfolium Mich. 



HAB. Moist woods. Can. to Car. W. to Rocky mountains. 

 June. T?. Shrub 2 5 feet high. Flowers greenish. 



2. R. radicans Linn. : stem climbing ; leaves ternate ; leafets petio- 

 late, ovate, acuminate, smooth, generally entire ; flowers in axillary 

 racemes, towards the top of the stem, dioecious ; fruit smooth. R. 

 toxicodendron, var. vulgare Mich. Pursh. R. toxicodendron, var. radi- 

 cans Torr. 



HAB. Woods and hedges. Can. to Car. June. *?. Stem 

 climbing. Flowers greenish. De Candolle thinks JR. radicans 

 distinct from R. toxicodendron. Both are very poisonous to 

 persons of peculiar constitutions. Barton's Collections. Big. 

 Mcd. Bot. iii. 19. Christy in N. Y. Med. fy Phys. Jour. N. S. i. 21. 



Poison Ivy. 



3. R. aromatica Ait. : branches slender, nearly smooth ; leaves ter- 

 nate ; leafets sessile, ovate-rhomboid, deeply toothed, tomentose be- 

 neath ; flowers in dense axillary racemes or catkins, dioecious ; fruit 

 pilose. Lobadiurn aromaticum Rqf. 



HAB. Mountains. N. Y. to Geor. W. to Miss. May, June. 

 V- Shrub 2 6 feet high. Flowers yellowish. Fruit red. 



** Leaves pinnate, smooth. 



4. JR. glabra Linn. : stem and branches smooth ; leafets in many 

 pairs, sessile, lanceolate, acuminate, sharply serrate, smooth, whitish 

 beneath ; flowers all perfect, in terminal compound panicles. 



HAB. Old fields. Can. to Geor. July. 1? .Shrub 6 12 feet high. 

 Flowers greenish-yellow. Fruit crimson, downy. 



5. R. copallina Linn.: branches terete, downy ; leafets 4 7 pairs, 

 with an odd one, oval-lanceolate, very entire, shining on the upper 



