530 



MORACEAE. 



i. Humulus Lupulus L,. Hop. 

 (Fig. 1261.) 



Hnmulus Lupulus L. Sp. PI. 1028. 1753. 



A dextrorsely twining or prostrate vine, often 25 

 long, very rough with stiff reflexed hairs. Leaves or- 

 bicular or ovate in outline, slender-petioled, deeply 

 3-7-cleft or some of the upper ones ovate, acute and 

 merely serrate; petioles YZ'-Z' long; stipules re- 

 flexed, ovate or lanceolate, acuminate, 4 // -i2 // 

 long; panicles of staminate flowers 2'-$' long; ripe 

 pistillate clusters (hops) i / -2^ / long; fruiting bracts 

 broadly ovate, concave, thin, glabrous or nearly 

 so, obtuse, much longer than the achenes; fruiting 

 calyx and achene strongly resinous-aromatic. 



In thickets and on river-banks, Nova Scotia to Man- 

 itoba, south to southern New York, Pennsylvania, in 

 the Alleghanies to Georgia, to Kansas, and in the 

 Rock}- Mountains to Arizona and New Mexico. Ex- 

 tensively escaped from cultivation. Native also of 

 Europe and Asia. July-Aug. Fruit ripe Sept. -Oct. 



5. CANNABIS L. Sp. PL 1027. 1753. 



A stout erect rough and puberulent herb, with alternate and opposite petioled digitately 

 5-n-divided thin leaves, persistent subulate stipules, and greenish dioecious axillary flowers, 

 the staminate panicled, the pistillate spicate. Staminate flowers with a 5-parted calyx, the 

 sepals distinct and imbricated, and 5 short stamens. Pistillate flowers solitary in the axils 

 of foliaceous bracts, consisting of a thin entire calyx clasping the sessile ovary, and 2 fili- 

 form caducous stigmas. Fruit a compressed achene. Endosperm fleshy; embryo curved. 

 [The classic name of hemp.] 



A monotypic genus of central Asia. 



i. Cannabis sativa L,. Hemp. 



(Fig. 1262.) 

 Cannabis sativa L,. Sp. PI. 1027. 1753. 



An annual branching herb, 3-io tall, the inner 

 fibrous bark very tough, the branches nearly erect. 

 Leaves divided to the base, the segments lanceo- 

 late or linear-lanceolate, acuminate at both ends, 

 sharply and coarsely serrate, 3'-6' long, %'-i' wide; 

 staminate panicles narrow, loose, peduncled, s'-s' 

 long; pedicels filiform, bracteolate, i // -3 // long; 

 pistillate spikes erect, leafy-bracted, i' long or less 

 in fruit; achene crustaceous, ovoid-oblong, about 

 2" high. 



In waste places, New Brunswick to Ontario and 

 Minnesota, south to North Carolina, Tennessee and 

 Kansas. Widely distributed in all temperate regions 

 through cultivation, and occasionally a troublesome 

 weed. Native of Europe and Asia. July-Sept. 



Family 10. URTICACEAE Reichenb. Consp. 83. 1828. 

 NETTLE FAMILY. 



Herbs (some tropical species shrubs or trees), with watery sap, alternate or 

 opposite mostly stipulate simple lea\-es, and small greenish dioecious, monoe- 

 cious or polygamous flowers, Yariously clustered. Calyx 2-5 -cleft, or of distinct 

 sepals. Petals none. Stamens in the staminate flowers as many as the lobes 

 or segments of the calyx (sepals) and opposite them, the filaments inflexed and 

 anthers reYersed in the bud, straightening at anthesis. Ch'ary superior, i -celled; 

 style simple; stigma capitate and penicillate, or filiform; oYule solitary, erect or 

 ascending, orthotropous, or in some genera parti}- amphitropous. Fruit an 

 achene. Endosperm oily, usually not copious; embryo straight. 



About 40 genera and 475 species of wide geographic distribution. 





