NETTLE FAMILY 367 



superior, l-i-elled, with 1 ortliotropous erect ovule; style and stigma 1. Embryo 

 straight. Endosperm oily. Fruit an achene. always enclosed or covered by 

 the calyx. 



Leaves opposite, toothetl, stipulate; hairs stinging; achene flattened. 



Pistillate calyx 4-parted, the segments almost distinct, the inner ones largest..!. Urtica. 



Pistillate calyx saccate, 2 to 4-toothed at orifice 2. Hespekocnide. 



Leaves alternate, entire, without stipules; hairs not stinging; achene ovoid; pistillate calyx 



tubular, 4-elef t 3. Pariet.«i.\. 



1. URTICA L. Nettle. 



Anuital or perennial herbs with stinging hairs. Leaves opposite, petioled, 

 3 to 7-nerved. with stipules. Flowers in ours monircions, clustered, the clusters 

 in axillary, often branching- spikes. Staminate flower with 4 sepals, 4 stamens 

 and a cuji-shaped rudiment of a pistil. Pistillate calyx' with the sepals itnequal. 

 the exterior smaller than the inner and at length enclosing the flattened achene : 

 ovary with sessile tufted or almost feathery stigma. Endosperm scanty. (Latin 

 name of the nettle.) 

 Pistillate and staminate flowers in separate spike-like inflorescences; perennial. 



Herbage gray ; leaves ovate to lanceolate 1. U. gracilis var. 



Herbage dark green ; leaves broadly ovate, cordate at base 2. U. californira. 



Pistillate and staminate flowers mixed in the same cluster; herbage dark green; annual. 

 3. V. urens. 



1. U. gracilis Ait. var. holosericea Jepsou n. comb. (U. holosericea Nuttall). 

 Stem erect, unbranched, 4 to 10 feet high; leaves long ovate to lanceolate, ccmi- 

 nionly green and with scattered bristles above, gray below with a short dense 

 pubescence, coarsely serrate, 3 to 5 inches long; petioles i^ to 2 inches long; 

 stipules narrowly oblong, mostly acutish, 2 to 6 lines long; flowers (as also in 

 ne.xt) sessile in small clusters (glomerules), the clusters in dense simple or 

 somewhat paniculately branched spikes ; pistillate spikes Y-2 to 2 inches long, the 

 staminate in axils below the pistillate and often twice as long; inner sepals not 

 or scarcely exceeding achene; achene elliptic but acutish at apex and often at 

 base, smooth. 



Along creeks, aljout damp spots in the hills, in moist valleys or in marshes. 

 common and often abundant: throughout California except in the desert regions; 

 extends north to "Washington. Eanges altitudiimlly from sea-level to 9,800 

 feet in the SieiTa Nevada. From the ordinary Eastern U. gracilis the Californiaii 

 plant differs only in its more abundant (albeit variable) pubescence and some- 

 what more densely flowered spikes, being more like it than the plant of the 

 southern Eocky ilts. (U. graeilenta Greene). In pubescence and in amount of 

 flower production var. holosericea is very variable. It has the following forms: 



Forma greeneii Jepson n. form. Herbage yellowish green ; achene with very 

 short and obscure stipe. — (Hei"ba flavo-viridis; achenium stipiti breve). — Etna, 

 Si-skiyou Co., E. L, Greene, no. 1028. 



Forma densa Jepson n. form. Herbage very gray; leaves on flowering portion 

 of stem reduced, the panictdate spikes eciualling or exceeding them, very num- 

 erous and forming a dense uninterrupted compound panicle. — (Herba cana 

 valde; inflorescentia paniculata duplicata densa). — Howell ]\It., W.L.J., Sept. 

 24, 1893; also lower Sacramento River (Andrus Island). 



Rcfs. — Ubtica gracilis Aitou, Hort. Kew. vol. 3, p. 341 (17S9). V. holosericea Nuttall, 

 Jour. Phil. Acad. n. s. vol. 1, p. 183 (1847), type loc. near Monterey, Gambel ; Jepson, Fl. W. 

 Mid. Cal. p. 147 (1901). 



tr. BREWERI Watson, Proc. Am. Acad. vol. 10, p. 34S (187.5), type loc. Los Angeles, Brewer, 

 no. 0.5 (1861). Leaves thin, finely hispi<l beneath, tuberculately roughened above; panicles 



