CANNABINACEAE 359 



disposed on elongated spike-like branches : calyx about 3 mm. broad : sepals oblong, obtuse, 

 sparingly pubescent or glabrate : achenes fully 1.5 mm. broad. 

 In moist sandy soil, Florida. Summer and fall. 



4. Boehmeria austrina Small. Perennial, copiously but finely pubescent, dull green. 

 Stems 5-9 dm. tall, closely pubescent : leaf-blades oblong to oblong-lanceolate, 9-14 cm. 

 long, thickish, acute or acuminate, crenate-serrate, velvety pubescent beneath, glabrate and 

 darker green above at maturity, cordate or rounded at the base, the main pair of lateral 

 nerves arising some distance above the base of the blade ; petioles relatively short,_ mostly 

 somewhat shorter than the blade: flower-clusters separated, on elongated spike-like 

 branches : calyx about 3 mm. broad ; sepals ovate, acute or acutish, copiously pubescent. 



In moist or sandy soil, Texas to Arizona. Summer and fall. 



5. Boehmeria nivea (L. ) Gaud. A shrub or shrubby plant. Stem and branches 

 pubescent with more or less spreading hairs : leaves alternate ; blades broadly ovate, 8-15 

 cm. long, somewhat acuminate, dentate, rounded, truncate or subcordate at the base, the 

 upper surface rough, the lower densely white-pubescent, long-petioled : flower-clusters 

 axillary, green, those of the pistillate flowers loosely branched. 



In waste places. South Carolina and Florida and about the large cities in the Gulf States. Intro- 

 duced from eastern Asia. Ramie. 



5. PARIETARIA L. 



Annnal or perennial, often flimsy herbs, with simple diffusely branched sometimes 

 pellucid stems. Leaves alternate : blades entire, 3-nerved. Involucres of 2-6 more or less 

 united bracts. Flowers polygamous, in clustered axillary cymes, the staminate with a 

 perianth of 4, or rarely 3 more or less united sepals, 4 or rarely 3 stamens and a rudimen- 

 tary ovary. Pistillate flowers with a perianth like that of the staminate, and a free ovary : 

 stigma tufted. Achene nearly terete, included, with a crustaceous pericarp. Pellitoey. 



Leaf-blades of an ovate, rhombic or an oblong type, relatively long-petioled. 



Bracts of the involucre linear or linear-lanceolate, acute : sepals lanceolate. 1. P. F/oridana. 



Bracts of the involucre oblong, sometimes narrowly so, obtuse : sepals ovate. 2. P. obtiisa. 



Leaf-blades of a lanceolate ty^e, relatively short-petioled. 3. P. Penmylvamca. 



1. Parietaria Floridana Nutt. Annual, slender, finely but often densely puberulent. 

 Stems ascending or spreading, 1-5 dm. long, often much branched : leaf-blades thin, numer- 

 ous, usually ovate to subrhombic, 0.5-5 cm. long, blunt at the apex or sometimes short- 

 acuminate but obtuse, entire, mostly obtuse at the base ; petioles filiform : flower-clusters 

 in nearly all the axils : bracts of the involucre linear or linear-lanceolate, 4 mm. long, 

 acute : sepals lanceolate, thin, acute or acutish : achenes ovoid, 1 mm. long, shining. 



In damp shaded places, New Hampshire to California, Florida and Mexico. Summer. 



2. Parietaria obtusa Kydb. Similar to P. Floridana in habit. Stems usually 

 branched at the base, the branches spreading, 0.5-2 dm. long, copiously but very finely 

 villous: leaf-blades oblong to ovate-oblong, 0.5-2 cm. long, scarcely or not at all con- 

 stricted below the apex, obtuse : bracts of the involucre oblong or narrowly oblong, obtuse : 

 sepals ovate, obtuse or rarely acutish. 



In shaded places, Colorado and Utah to Texas and Arizona. Spring and summer. 



3. Parietaria Pennsylvanica Muhl. Annual, slender, finely pubescent. Stems weak, 

 ascending or reclining, 1-4 dm. long, simple or branched : leaf-blades thin and flimsy, 

 lanceolate or elliptic or sometimes oval or ovate, 1-6 cm. long, obtuse or acuminate at the 

 apex, entire, acute or acuminate at the base ; petioles slender : flower-clusters sessile in all 

 but the lower leaf-axils : bracts of the involucre linear, 4-5 mm. long : sepals oblong or 

 lanceolate, acute : achenes oval, 1 mm. long, shining, minutely apiculate. 



On shaded banks and rocks, Ontario to British Columbia, Florida and Mexico. Summer. 



Family 2. CANNABINACEAE Liudl. Hop or Hemp Family. 



Annual or perennial, often coarsely pubescent herbs, with erect or twining 

 stems. Leaves opposite or sometimes alternate : blades toothed, lobed or 

 divided, membranous, petioled : stipules persistent. Flowers dioecious : stami- 

 nate in panicled racemes, with 5 sepals, and 5 stamens, or fewer or more. 

 Pistillate flowers in bracted spikes, with an entire perianth, and a gynoecium of 

 2 united carpels. Ovary 1-celled. Styles or stigmas:2, subulate. Ovule soli- 

 tary, pendulous. Fruit an achene, subtended by and often enclosed in a bract : 



