NETTUv FAMILY. 



lerbs with stinging hairs. 



Leaves opposite; both kinds of flowers 4-parted; achene straight 

 Leaves alternate; staminate flowers 5-parted; acht-nc obliim- 

 lerbs without stinging hairs. 



1 'lower-clusters panicled or spiked, not involucrate; leaven mostly opposite 

 Pistillate calyx 3-parted or of 3 sepals. 

 Pistillate calyx 2~4-toothed or entire. 

 Flower-clusters involucrate by leafy bracts; leaves alternate. 



531 







i. URTICA L. Sp. PI. 983. i; 



Annual or perennial simple or branching herbs, with stinging hairs, opposite 3-7- 

 erved petioled dentate or incised leaves, and distinct or connate stipules. Flower- 

 all and numerous, axillary, cymose- paniculate, or glomerate, dioecious, monoecious or an- 

 ogynous. Staminate flowers with a deeply 4-partol <-aK v and j stamens. Pistillate 

 lyx 4-parted, the segments unequal, the exterior ones usually smaller than the inner; 

 ary straight; stigma sessile or nearly so; ovule erect, orthotropous. Achene compressed. 

 vate or oblong, enclosed by the persistent membranous or slightly fleshy calyx. Seed- 

 at thin; endosperm little; cotyledons broad. [The ancient Latin name.] 



About 30 species of wide geographic distribution, 

 rennials, 2-7 tall; flower-clusters large, compound. 



Leaves ovate, cordate at base. 



Leaves laciniate, rarely cordate. 

 Annuals. 6' -2 1 A tall; flower-clusters small, mostly glomerate. 



Leaves oval, laciniate-dentate: plant leafy at the top. 



Leaves ovate or lanceolate, crenate; upper leaves vt-ry small. 



I f. i fii': 



|. / '. ilianttifdi 



i. Urtica dioica L,. Stinging or Great 

 Nettle. (Fig. 1263.) 



t'i iica dioica L. Sp. PI. 984. 1753. 



Perennial, densely beset with stinging hairs, 

 stem rather stout, 2-4 tall, puberuleut above. 

 Leaves thin, ovate, long-petioled, acute or acu- 

 minate at the apex, cordate at the base, sharply 

 or incisely serrate with triangular or lanceolate 

 acute teeth, pubescent beneath, 3-5-nerved, 3'- 

 5' long, i '-3' wide; petioles very slender, shorter 

 than the blades; stipules lanceolate; flower- 

 clusters large, compound, cymose-paniculate; 

 flowers dioecious or androgynous. 



In waste places, Nova Scotia to Ontario and Min- 

 nesota, south to South Carolina and Missouri. 

 Naturalized from Europe. Native also of Asia. 

 Plant lower, stouter and much more stinging than 

 the following species. July-Sept. 



2. Urtica gracilis Ait. Slender Nettle. 

 (Fig. 1264.) 



t >//((/ tfrji'i/is Ait. Hort. Kcw. 3: 341. 1789. 



Perennial, sparingly armed with stinging 

 hairs, stem usually slender, erect, simple or with 

 few erect branches, 2-7 tall. Leaves lanceo- 

 late or ovate-lanceolate, slender-petioled, long- 

 acuminate at the apex, narrowed or sometimes 

 rounded at the base ( rarely subcordate), sharply 

 serrate, 3-5-nerved, sparingly pubescent, 3 / -6 / 

 long, >'-i.H' wide; petioles shorter than the 

 blades, usually bristly; stipules lanceolate; 

 flower-clusters compound, smaller than those of 

 the preceding species, but commonly longer than 

 the petioles; flowers dioecious or androgynous. 



In dry soil, Nova Scotia to British Columbia, 

 south to North Carolina, Louisiana and Kansas. 

 June-Oct. 



