412 URTICACE^. (nettle FAMILY.) 



with a single erect orthotropoiis ovule. Stigma simple or tufted. Ache- 

 nium oouimonly enclosed in the dry persistent calyx. Embryo straight, 

 in the axis of lleshy albmnen. 



Synopsis. 



• Plants armed with stinging hairs. 



1. URTICA. Stamens 4. Ptigma tufted. Achenium straight. 



2. LAPORTEA. Stamens 5. Stigma subulate. Achenium oblique. 



* * Plants destitute of stinging hairs. 

 ■I- Flowers in cymose clusters. 

 3- PILE.\. Clusters naked. Calyx-lobes unequal. Leaves opposite. 



4. PARIETARLA. Clusters involucrate. Calyx-lobes equal. Leaves alternate. 



■(- -I- Flowers in spiked clusters. 



5. BCEHMERLA. Stigmas subulate, leaves opposite or alternate. 



1. URTICA, Tourn. Nettle. 



Flowers monoecious or dioecious. Calyx of the sterile flower 4-parted. Sta- 

 mens 4, inserted around the abortive ovary. Calyx of the fertile flower 4-sepa- 

 lous, unequal ; the inner ones dilated in fruit, and enclosing the achenium. 

 Stigma sessile, tufted. Achenium straight, ovate, smooth, compressed. — Herbs, 

 witii stinging hairs, opposite leaves, and greenish flowers, in paniclcd spikes or 



close clusters. 



* Flowers in panicled or simple spikes. 



1. U. gracilis. Ait. Stem tall, 4-angled, smootliisli, slender ; leaves long- 

 petioU'd, ovatu-huiceolate, coarsely serrate, acute, rounded at the base, 3-5- 

 nerved, smoothisli, the petioles bristly ; spikes very slender, loosely paniclcd. 

 (U. procera, Willd.) — Low ground in the upper districts, and nortliward. July 

 and Aug. H. — Stem 3° - 4° high, mostly simple. Leaves thin, 4' -6' long. 



2. U. dioica, L. Hispid tliroughout ; stem 4-anglcd, pubescent above, 

 brandling ; leaves rather short-petiolcd, ovate, cordate, acuminate, coarsely ser- 

 rate, pubescent beneath ; spikes much branched ; flowers often dia'cious. — 

 Waste places. In Carolina, Pursh. Introduced. June - Aug. y. — Stem 2°- 

 3" high. Leaves 3' -4' long, thicker than in No. 1, and flowers larger. 



3. U. capitata, Willd. Stem 4-anglcd, roughish ; leaves large, long- 

 petiolcd, rough, oblong-ovate, slightly cordate, coarsely sciTate, 3-ncrved ; those 

 on the branches alternate ; spike solitary, leafy at tlic summit. — Wet shaded 

 places, North and South Carolina, Curtis, Elliott. July and Aug. — Stem 3*^ - 

 5° liigii. 



* * Flowers in simple clusters shorter than the petioles. 



4. XJ. urens, L. Stem 4-angled, hairy ; leaves ovate, coarsely scrrato, 

 !>-ncrved, hairy ; clusters by pairs in each axil, loose, pedunclcd. — Damp soil. 

 Introduced. Dec. -Feb, (J) — Stem 1° high. 



5. U. ChamsedryoideS, Pursh. Stem smooth ; leaves small, nearly ses- 

 sile, ovate, coarsely serrate, hairy beneath, liuiry juxl bristly above; clusters 

 nearly sessile, plohoso, dense ; culyx liairy. — St. Simon's Island, Georgia, 

 Flliotl. Feb. and March. — Stem 4' - G' high. 



