Urtica.] URTICACEuE. 363 



linear-oblong. Panicles 1-3 in., in pairs, males lax- females dense-fld., re- 

 curved.— Distbib. N. temp, regions (Arctic), S. Africa, Andes. —The young 

 leaves are a good pot-herb, and yield a green dye. 



3. U. pilulif'era, L. ; annual, glabrous except for the stinging hairs, 

 leaves ovate or cordate entire or toothed, female flowers capitate. 

 Waste places, E. England, chiefly near the sea; (an alien, Wats.); fl. June- 



Aug. — Stem 1-2 ft., simple or branched. Leaves 1-3 in., long-petioled ; 



stipules ovate. Male spikes panicled, peduncles very slender elongate. 



Female heads ^ in. diam. ; peduncles § in., stout. Flowers much larger than 



in the preceding species. — Distkib. Europe, N. Africa, W. Asia ; introd. 



in N. America. — The most virulent British nettle. 

 U. pilulifera proper ; leaves deeply serrate. — Var. U. Dodar'tii, L. ; leaves 



entire or nearly so. 



3. PARIETA'RIA, Tournef. Pellitory. 



Herbs, rarely shrubs. Leaves alternate, quite entire, exstipulate. 

 Flowers clustered or cymose, polygamous, 1-3-bracteate, proterogynous. 

 Perianth of male 4-partite, valvate in bud ; of female tubular, 4-fid. 

 Stamens 4. Style long or short, stigma papillose. Fruit minute, included 

 in the enlarged calyx. — Distrib. Temp, and trop. regions ; species 8. — 

 Etym. paries, from growing on walls. 



P. officinalis, L. ; leaves triple-nerved. P. diffu'sa, Koch. 

 Old walls, hedgebanks, &c, from Boss southd. ; Ireland ; Channel Islands ; fl. 

 June-Oct. — Perennial, pubescent with curled hairs. Rootstock short, woody. 

 Stems 1-2 ft., tufted, erect, or decumbent, terete ; branches slender, leafy. 

 Leaves ^-4 in., elliptic-lanceolate or ovate, obtuse or acute, petiole slender. 

 Flowers in axillary clusters, mostly 2-sexual, in a 3-6-lobed few-fld. involucre. 

 Calyx elongate and tubular after flowering. — Distrib. Europe, N. Africa, 

 W. Asia. 



4. HU'MULUS, L. Hop. 



Perennial, twining herbs ; juice watery. Leaves opposite, lobed ; stipules 

 connate. Flowers minute, dioecious. — Male panicled. Sepals 5, free, 

 imbricate in bud. Stamens 5, adnate to the base of the sepals ; anthers 

 oblong, basifixed, slits subterminal. — Females in pairs in the axils of the 

 bracts of a dense spike which forms a catkin-like head in fruit, bracteate 

 and bracteolate. Sepal 1, membranous, bract-like. Ovary free, com- 

 pressed ; styles 2, subulate, stigmatic all over ; ovule 1, pendulous, cam- 

 pylotropous, micropyle superior. Fruit dry, indehiscent, enclosed in the 

 sepal. Seed pendulous, testa coriaceous, albumen ; embryo a flat helix. 

 — Distrib. N. temp, and trop. regions ; species 2. — Etym. doubtful. 



H. Lu'pulus, L. ; bracts of fruit much enlarged scarious. 

 Hedges and copses, from York southd. ; Channel Islands ; naturalized N. to 

 Renfrew and Elgin, and in Ireland ; ascends to 1,000 ft. in the Highlands 

 fl. July-Ang. — Rootstock stout, branched. Stems tall, scabrid, almost prickly 



