G4 URTICACE.E. Uriica. 



- * Beset witli stinging hairs : leaves opposite, dentate, stijmlate : akene compressed. 



1. Urtica. Sepals 4, distinct, the inner ones largest in the fertile flowers and enclosing the 



akene. 



2. Hesperocnide. Staminate calyx 4-parted; pistillate tubular, unequally 2-4-toothed and 



enclosing the akene. 



* * Unarmed : leaves alternate, entire, without stipules : akene ovoid. 



3. Parietaria. Inflorescence involucrate-bracted. Staminate calyx 4-parted ; pistillate tubular- 



campanulate, 4-lobed, enclosing the akene. 



1. URTICA, Tourn. Nettle. 



Flowers monoecious or dioecious, green, clustered in axillary geminate racemes, 



spikes or loose heads, Avithout bracts : staminate flowers on jointed pedicels, with 



4 sepals, 4 stamens, and a rudimentary cup-shaped ovary ; the pistillate with 4 



sepals, the 2 outer small and spreading, the inner erect, becoming membranous and 



enclosing the flattened ovate akene : stigma sessile, capitate, tufted : albumen scanty. 



— Herbs, armed with stinging hairs, with obtusely 4-angled sulcate stems ; leaves 



oi>posite, serrate, with distinct lateral stipules ; fruit persistent. 



A wide-spread genus in temperate and subtemperate regions, of 30 or 40 species, about a third 

 American. 



* Perennials, V'lili runnlnr/ rootstoclcs : inflorescence uniseocual ; panicles usually 

 exceeding the petioles : stipules large, entire. 



1 . U. holosericea, Nutt. Tall and stout, 5 to 8 feet high, more or less bristly, 

 finely and densely tomentose especially on the lower side of the leaves : stipules 

 membranous, -| inch long, oblong, obtuse or acute ; leaves thick, oblong- to ovate- 

 lanceolate, acuminate, 2 to 4 inches long, rounded or subcordate at base, coarsely 

 serrate, on short stout petioles : staminate flowers in loose slender diftuse panicles 

 nearly equalling the leaves ; pistillate panicles denser and shorter : inner sepals 

 ovate, densely hispid, \ line long, about equalling the broadly ovate akene. — PI. 

 Gambel. 183; Watson, Proc. Am. Acad. x. 349. U. tracht/carpa, AYeddell, 

 Monogr. 95, ct DC. Prodr. xvi^ 58. U. dioica, var. occidentalis, AVatson, Bot. 

 King Exp. 321. 



Throughout the State, and eastward to Utah ; especially common in S. California. Nuttall 

 describes the leaves as sometimes (probably the lowest ones) a span long and long-petioled. 



2. U. Breweri, Watson. Tall and stout, grayish with a short somewhat hispid 

 pubescence or nearly glabrous, and with scattered bristles : stipules membranous, 

 oblong-lanceolate : leaves thin, finely pubescent, soon glabrate or roughish above, 

 ovate to oljlonglanceolate, 2 to 6 inches long, acute or acuminate, rounded or 

 slightly cordate at base, coarsely serrate, on slender petioles 1 to 3 inches long or 

 more : flowers in short open panicles scarcely exceeding the petioles : sepals obovate 

 or rounded, obtuse, minutely hispid, nearly a line long and nearly twice longer than 

 the broadly ovate akene. — Proc. Am. Acad. x. 348 ; Eothrock, Bot. AVheeler, t. 25. 



Frequent about Los Angeles {Brewer) and ranging eastward to S. Colorado ( Wolf) and W. 

 Texas, Bigrhnr. 



3. U. Lyallii, Watson, 1. c. Tall, rather slender, more or less pubescent, be- 

 coming nearly glabrous, with scattered bristles : stipules large, membranous, broadly 

 oblong, obtuse ; leaves ovate, somewhat cordate at base, acute, 3 to 6 inches long or 

 more, coarsely serrate, on slender petioles 2 to 4 inches long : flowers in loose slen- 

 der spreading panicles, equalling or shorter than the petioles : sepals broadly ovate 

 or rounded, obtuse, shorter than the broadly ovate akene, Avhich is |- line long. 



A very large-leaved species, collected in Marin County {Kellogg) and northward in the Cascade 

 Mountains and at Vancouver Island, LyaU. 



