URTICACEJS. (NETTLE FAMILY.) 395 



axis of albumen. Herbs (01 in the tropics often shrubs or trees), with a 

 watery (innocuous) juice, a tough fibrous bark, and opposite or alternate 

 leaves : many are armed with stinging hairs. 



* Calyx of the fertile flowers of 2 - 4 se'parate or r/early separate sepals. 

 t- Plant beset with stinging bristles. 



5. URTICA. Sepals 4 in both sterile and fertile flowers. Achenium straight and erect, en- 



closed by the 2 inner and larger sepals. Stigma capitate-tufted. Leaves opposite. 



6. LAPORTEA. Sepals 5 in the sterile flowers, 4 in the fertile, or apparently only 2, the two 



exterior minute and obscure Achenium very oblique and bent down, nearly naked. 

 Stigma long and awl-shaped Leaves alternate. 



- - Plant wholly destitute of stinging hairs. 



7- PILEA. Sepals 3 or 4, those of the fertile flowers all or all but one small. Achenium 

 partly naked, straight and erect. Stigma pencil-tufted. Leaves opposite. 

 * * Calyx of the fertile flowers tubular or cup-shaped, enclosing the achenium. 



8. BQUHMERIA. Flowers monoecious, glomerate, the clusters spiked, not involucrate. Style 



long and thread-shaped, stigmatic down one side. 



9. PARIETARIA. Flowers polygamous, in involucrate-bracted clusters. Stigma tufted. 



SUBORDER IV. CANNABINE^E. THE HEMP FAMILY. 



Flowers dioecious; the sterile racemed or panicled ; the fertile in clus- 

 ters or catkins. Filaments short, not inflexed in the bud. Fertile calyx 

 of one sepal, embracing the ovary. Stigmas 2, elongated. Ovary 1-celled, 

 with an erect orthotropous ovule, forming a glandular achenium in fruit. 

 Seed with no albumen. Embryo coiled or bent. Herbs with a water} 

 juice and mostly opposite lobed or divided leaves, a fibrous inner bark, &c. 

 (yielding bitter and narcotic products). 



10. CANNABIS. Fertile flowers spiked-clustered. Anthers drooping. Leaves 5 - 7-divided. 

 11 HUMULUS. Fertile flowers in a short spike forming a membranaceous catkin in fruit 

 Anthers erect. Leaves 3 - 5-lobed. 



SUBORDER I. ULjyiCEJB. THE ELM FAMILY. 



r. tf I, TO ITS, L. ELM. 



Calyx bell-shaped, 4 - 9-cleft. Stamens 4-9, with long and slender filaments. 

 Ovary 1 - 2-cclled, with a single anatropous ovule suspended from the summit 

 of each cell : styles 2, short, diverging, stigmatic all along the inner edge. 

 Fruit (by obliteration) a 1-celled and 1 -seeded membranaceous samara, winged 

 'all around. Albumen none : embryo straight; the cotyledons large. Flowers 

 perfect or polygamous, purplish or yellowish, in lateral clusters, in our species 

 preceding the leaves, which are strongly straight-veined, short-petioled, and 

 oblique or unequally somewhat heart-shaped at the base. Stipules small, cadu- 

 cous. (The classical Latin name.) ^ 



# Flowers appearing nearly sessile : fruit orbicular, not dilate : leaves very rough above. 



1. IT, fulva, Mich. (SLIPPERY or RED ELM.) Buds before expansion 

 soft-downy with rusty hairs (large) ; leaves ovate-oblong, tape^-nointed, doubly 

 serrate (4' -8' long, sweet-scented in drying), soft-downy underneath or slightly 



