1<26 FLORA OF PHILADELPHIA. ■ 



4. HUMULUS L. 



1. HuMULUS LuPULUS L, Hop. M. p. 341. Alluvial banks. Escaped 

 from cultivation. Summer. 



5. CANNABIS L. 



1. Cannabis sativa L. Hemp. M. p. 341. Waste places. Summer. 



Family 3. URTIGACEAE- Nettle Family. 



Herbs with stinging hairs. 



Leaves opposite; both kinds of flowers 4-parted; achene straight. 



1. Urtica. 

 Leaves alternate ; staminate flowers 5-parted ; achene oblique. 



2. Urticastrum. 

 Herbs without stinging hairs. 



Flower-clusters panicled or spiked, not involucrate leaves mostly opposite. 



Pistillate calyx 3-parted or of three sepals. 3. Adicea. 



Pistillate calyx 2-4 toothed or entire. 4. Boehmeria. 



Flower-clusters involucrate by leafy bracts; leaves alternate. 



5. Parietaria. 



1. UETICA L. Nettle. 



Perennials, 0.6-2.2 m. tall; flower clusters large, compound. 



Leaves ovate, cordate at base. 1. U. dioica. 



Leaves laciniate, rarely cordate. 2. U. gracilis. 



Annuals 1..5-4 dm. tall, flower clusters small, oblong, rather dense. 



3. U. urens. 



1. Urtica dioica L. M. p. 342. Waste places and roadsides. Summer. 



2. Urtica gracilis Ait. M. p. 342. Dry soil. Summer. 



BmcA's— NockamLxon (Fr.) (Ja.). Montgomery— ShannonviWe (Cr.). 

 Z>etot(;are— Haverford, Nitre Hall Mill Dam, Dr. Geo. Smith (Fu.), Lans- 

 downe (Pe.), Swarthmore (Pr.), Wallingford (Wn.). Lmicaster— Peach 

 Bottom (Le.). Northampton — 'Ei&.?,ton, Porter (B. C). Dauphin — 

 Steelton (Wn.). 



Burlington — Bordentown (Wn.). Gloucester — Swedesboro (Li.), 

 Mercer — Trenton (C). Hunterdon — Booles Island, J. S. Moyer (B. C). 



3. Urtica urens L. M. p. 342. Waste places. Summer. 



Philadelphia — Wissahickon (Je.). Montgomery — Shannonville (Cr.). 

 Camden— Kaighns Point (Ja.). Hunterdon— Below Booles Island(C.). 



2. UETICASTEUM Fabr. 



1. Urticastrum divaricatum (L.) Kuiitze. Wood Nettle. M. p. 343. 

 Rich woods. Summer. 



3. ADICEA Raf. 

 1. Adicea pumila (L.) Raf. Bichweed. M. p. 343. Cool and moist shaded 

 places. Summer. 



4. BOEHMERIA Jacq. 

 1. Boehmeria cylindrica (L.) Willd. False Nettle. M. p. 343. Moist 

 ground. Summer. 



