358 URTICACEAE . 



1. Adicea herniarioidea ( Sw. ) Small. Annual, very slender, glabrous. Stems fili- 

 form, 3-10 cm. long, prostrate or decumbent, soft, pellucid, simple or branched : leaf-blades 

 suborbicular to broadly oval, 2-4 mm. long, obtuse at the apex, entire, acute at the base, 

 marked on the upper surface with pale transverse ridges ; petioles filiform, somewhat 

 shorter than the blades : fiower-clusters very small, shorter than the petioles : sepals 

 oblong, acutish : achene 0.4 ram. long, oblong-ovoid, lenticular. \_Pilea hernarioides {Sw.) 

 Lindl.] 



In dry woods and hammocks, Key West, Florida. Also in the West Indies. 



2. Adicea mlcrophylla ( Sw. ) Kuntze. Annual or biennial, slender, glabrous. 

 Stems erect or ascending, or sometimes creeping at the base, 5-20 cm. long, fleshy, simple 

 or mostly branched : leaf-blades elliptic or oblanceolate, 5-10 ram. long, acute or acutish at 

 the apex, entire, acuminate at the base, transversely wrinkled ; petioles filiform, shorter 

 than tlie blades : flower-clusters very small, shorter than the petioles : sepals ovate, very 

 thin, acutish : achenes oblong, 0.4 mm. long, lenticular. [Pilea microphylla (Sw. ) Liebm. ] 



In rocky woods, western Florida. Also in the West Indies. 



3. Adicea pumila (L. ) Raf. Annual, fleshy, glabrous or finely pubescent. Stems 

 erect or decumbent, 1-7 dm. tall, obtusely angled, often branched, watery, pellucid : leaf- 

 blades ovate to elliptic, 3-10 cm. long, usually short-acuminate, coarsely crenate-serrate, 

 broadly cuneate at the base ; petioles as long as the blades or somewhat sliorter : panicles 

 spreading, shorter than the subtending petioles : sepals lanceolate, each of those of the pis- 

 tillate flowers accompanied by a staminodiura : achene ovoid, 2 mm. long, acutish. [Pilea 

 pumila (L. ) A. Gray.] 



In damp shaded places, New Brunswick to Minnesota, Florida and Louisiana. Summer and fall. 



4. BOEHMERIA Jacq. 



Herbs, shrubs or trees, more or less pubescent with stingless hairs. Leaves alternate 

 or opposite : blades often 3-nerved, toothed or rarely lobed : stipules mostly free. Flowers 

 monoecious or dioecious, in dense contiguous or distant clusters on slender branches : the 

 staminate with a perianth of 4 or rarely 3-5 partially united sepals, 4 or rarely 3-5 stamens 

 and a rudimentary ovary. Pistillate flowers with a perianth of 2-4 united sepals and a ses- 

 sile or stalked ovary : stigma elongated. Achene flattened, included, the pericarp some- 

 what crustaceous. False Nettle. 



Leaf-blades not white-pubescent beneath : native species. 



Leaf-blades leathery, finely serrate ; petioles much shorter than the blades. 1. B. scabra. 



Leaf-blades relatively thin, coarsely serrate ; petioles as lon^ as the blades or little shorter. 



Main pair of lateral nerves arising at the base of the leaf-blade. 2. B.cylmdrica. 



Main pair of lateral nerves arising some distance above the base of the leaf-blade. 

 Leaf-blades glabrous or merely puberulent and slightly pubescent about the 



nerves beneath : calyx glabrous or nearly so at maturity. 3. B. dccnrrcns. 



Leaf-blades velvety pubescent beneath : calyx copiously pubescent. 4. B. austrina. 



Leaf-blades white-pubescent beneath : introduced species. 5. B. nivea. 



1. Boehmeria scabra (Porter) Small. Perennial, rough-pubescent or nearly gla- 

 brous. Stems 2-12 dm. tall, rarely branched, very leafy : leaf-blades leathery, firm, ovate 

 or elliptic-ovate, 2-5 cm. or rarely 10 cm. long, acute or short-acuminate, finely serrate, 

 cordate or rounded at the base, short-petioled ; petioles 1 cm. or rarely 2 cm. long : spikes 

 continuous, dense: calyx 3.5 mm. broad, the sepals ovate-lanceolate, strongly hooded at 

 the apex: achenes suborbicular, sometimes broader than high, nearly 1.5 mm. broad, 

 pointed, quite oblique at the base. [Boehmeria cylindrica var. scabra Porter.] 



In swamps, New York to Michigan, Kansas, Florida and Texas. Summer and fall. 



2. Boehmeria cylindrica (L. 1 Willd. Perennial, bright green, pubescent with 

 rigid straight or hooked hairs or nearly glabrous. Stems 2-10 dm. tall, simple or branched 

 above : leaf-blades thin, ovate to lanceolate, 3-1 2 cm. long, acuminate, coarsely-serrate, 

 rounded or obtuse at the base ; petioles slender, often nearly as long as the blades : flower- 

 clusters dense, forming usually interrupted spikes on slender branches : calyx 3 mm. broad : 

 sepals ovate-lanceolate : achenes suborbicular, 1 mm. broad, pointed, oblique at the base, 

 ciliate. 



In woods and low ground, Quebec to Minnesota, Florida and Kansas. Summer and fall. 



3. Boehmeria decurrena Small. Perennial, nearly glabrous at maturity, deep green. 

 Stems 7-12 dm. tall, sometimes inconspicuously pubescent : leaf-blades thin, lanceolate 

 to ovate-lanceolate, 10-18 cm. long, acuminate, serrate or crenate-serrate, with scattered 

 hairs on and about the nerves beneath, deeper green above, rounded or very slightly cor- 

 date at the base, the main pair of lateral nerves arising some distance above the base of the 

 blade ; petioles slender, nearly as long as the blades or somewhat shorter : flower-clusters 



