IRRITANT POISONS 79 



(2, 3, 4) Iridacece. — Flowering-stem obovate-unguiculate, 

 erect, clustered, 4-5 flowered, glaucous, forked, 3 ft.; May; 

 perennial. — Leaves tufted, few, sword-shaped, glaucous. 



Toxic Principle.— IRIDIN. 



(5) Iridacece. — Flowers variously coloured ; February-March. 

 — Leaves generally 2 to a tuft, as high as flower at flowering- 

 time, afterwards growing to 1 ft. or more. 



Toxic Principle. — IRIDIN, also contained in I. tuberosa and 

 others. Viola canina odorata, V. palmensis, V. sylvatica, 

 V. tricolor. 



. . . the nests 

 And nooks retain their long-ranged vesture-chests 

 Empty and smelling of the Iris-root. 



Browning: " Sordello.'' 



POLYGALA SENEGA {North America). 147. 



SENECA SNAKE ROOT. 



Polygalacece. — Leaves alternate, sessile, lanceolate. — Stems 

 numerous, slender, erect. — Flowers crowded in a terminal 

 spike ; petals 3. — Seeds 2. — 6-12 ins. ; perennial ; May and June ; 

 pink. 



Toxic Principle. — POLYGALIN, also contained in P. amara. 



. . . grass out of a watery rock, 

 And their long tangles in each other lock. 



Shelley: " The Medusa.'' 



RHEUM PALMATUM {Cultivated in Britain). 148. 



TURKEY RHUBARB — MEDICINAL RHUBARB — PALMATE-LEAVED 

 RHUBARB — SHARA-MOTO — DJUNTSA. 



PolygonacecB. — Root with a vertical axis 1 ft. long, and 

 equally thick; many slender rootlets 2 ft long. — Flowering- 

 stem 7-10 ft.; cylindrical; hollow; striate; red. — Leaves at 

 root on petioles 2 ft. long; 5-lobed; deeply and unequally 

 serrate; stem-leaves becoming smaller. — Flowers numerous; 

 on spreading pedicels ; 2-3 together on branchlets of panicle, 



