Nettle Family 107 



greenish. Petals none. Calyx mostly 4-parted or 

 sepals distinct, with as many stamens opposite the 

 lobes ; filaments inflexed and anthers reversed in the 

 bud, straightening elastically at anthesis. Ovary super- 

 ior 1-celled, 1-ovuled ; style and stigma 1. Fruit an 

 achene. Endosperm oily, not copious ; embryo straight. 



Herbs with stinging hairs ; leaves opposite. 



Sepals 4, distinct. 1. UBTICA. 



Staminate calyx 4-parted; pistillate unequally 2-4-toothed. 



2. HESPEROCNIDE. 

 Herbs without stinging hairs; leaves alternate. 3. PARIETABIA. 



1. UBTICA L. NETTLE. 



Annual or perennial, simple or branching herbs, with 

 stinging hairs, and opposite 3 7-nerved petioled serrate or 

 dentate stipulate leaves. Flowers clustered in axillary 

 geminate racemes or heads. Staminate flowers 4-mer- 

 ous. Pistillate calyx with unequal sepals, the inner 

 larger and at length enclosing the flattened achene. 

 Stigma sessile, tufted. 



* Annual. 



1. U. urens L. Erect, branching from the base or sometimes 

 simple, 25-50 cm. high ; leaves ovate or oblong-ovate, deeply and 

 sometimes doubly serrate, 1-4 cm. long, on slender petioles of 

 about the same length; stipules 4 mm. long; flower clusters 

 rather dense, mostly shorter than the petioles ; flowers androg- 

 ynous, mainly pistillate. 



Common in gardens and waste places. Native of Europe. 



** Perennials. 



2. U. holosericea Nutt. Stems simple, stout, 1-3 m. high or 

 more, more or less bristly and finely pubescent ; leaves finely and 

 densely pubescent beneath, less so above or with only a few scat- 

 tering bristles, ovate to lanceolate, 5-10 cm. long, the upper much 

 shorter, on petioles % as long, coarsely serrate; stipules narrow- 

 ly oblong, acute or obtuse, 6-10 mm. long ; Staminate flower 

 clusters rather loose, nearly equaling the leaves ; pistillate denser 



