S60 POLEMONIUM. [class v. order i. 



GENUS XIX. POLEMO'NIUM Linn. Jacob's Ladder. 



Nat. Ord. Pojlemonia'ce^. Juss. 



Gen. Char. Calyx five-cleft. Corolla wheel-shaped, with a short 

 tube. The limb of five lobes. Stamens dilated and hairy at the 

 base, closing the mouth of the tube. Stigmas three-cleft. 

 Anthers incumbent. Capsule of three cells and three valves. 

 Seeds numerous. — Name from 'KoKi^oc, war ; on account, accord- 

 ing to a tale related by Pliny, of its having been the occasion of a 

 war between two Kings, from a dispute that arose between them 

 as to who was the discoverer of its uses. He further states that 

 the Polemonium of the ancients was called Chilodynamia, from 

 Xi^^ioi and ^uvapj, on account of the many virtues that it is 

 related to possess. 

 1. P. cceru'leum, Linn. (Fig. 342.) Jacoh's Ladder, or Greek 

 Valerian. Stem smooth, leafy ; leaves pinnated ; leaflets oblong- 

 lanceolate, smooth, panicle clothed with glandular hairs; flowers 

 erect. 



English Botany, t. 14. — English Flora, vol. i. p. 287. — Hooker, 

 British Flora, vol. i. p. 113. — Lindley, Synopsis, p. 168. 



Root of branched fibres. Stem erect, smooth, slightly angular, from 

 one to two feet high, leafy, green, or sometimes pinkish. Leaves alter- 

 nate, the lower ones on long common stalks, the upper short. Leaflets 

 smooth, sessile, or on short footstalks, oblong-lanceolate, opposite or 

 alternate, with an odd one at the end, and all of nearly an equal size. 

 Inflorescence a branched panicle, more or less clothed with soft glan- 

 dular hairs. Flowers numerous, large, blue, sometimes white, on 

 short stalks, mostly crowded. Calyx about half five-cleft; the seg- 

 ments ovate-lanceolate, acuminate, more or less thickly clothed with 

 glandular hairs, especially at the base, and each segment with one or 

 three simple or branched ribs, persistent, and enveloping the capsule, 

 enlarging after flowering as it advances to maturity. Corolla wheel- 

 shaped, with a short tube, and large five lubed spreading limb, regular 

 or somewhat unequal, imbricated in estivation, mostly waved on the 

 margin, and beautifully pencilled over with dark purple veins. 

 Stamens alternating with the segments of the corolla, and nearly as 

 long. The filaments dilated and hairy at the base, closing over the 

 mouth of the tube. Style simple, as long as the corolla. Stigma 

 three-cleft. Capsule triangular, of three cells, three valves, each valve 

 with an external furrow and prominent internal rib attached to the 

 central placenta, and forming the internal walls of the cells. Seeds 

 angular, or oval. 



Habitat.— Banks and bushy places ; rare. On the banks of the 

 river Derweut, near Fox Inn, and Castleton Dale, Derbyshire, not 



