298 ORDER 114. URTICACE.E. 



11. PACHYSANDRA, MX. Flowers S , apetalous, in bracted spikes 

 Calyx 4-parted. $ Filaments 4, long-exserted, flat. $ Styles 3, recurved, 

 Capsule 3-horned, 3-celled, cells 2-seeded. U Prccumbent stems from 

 long creeping root-stocks. Leaves alternate. 



P. procumbens MX. Lvs. ovate to obovatc, coarsely toothed, clustered above the 

 spikes, which are all near the base of the stem. Va. to Ky., and S. March May. 



12. BUXUS, L. BOXWOOD. Flowers 8 , axillary. $ Calyx 3-leaved, 

 petals 2. Sta. 4. $ Cal. 4-sepalled. Pet. 3. Sty. 3. Caps, with 3 beaks 

 and 3 cells. Seeds 6. > b Leaves opposite, ovate, entire, smooth. 



B. 8EMPERVIRENS. A tree of slow growth, fine-grained wood, in Europe. The dwarfed 

 varieties are planted in gardens for edgings. 



ORDER CXIV. URTICACEJE. NETTLEWORTS. 



Plants of various habit, with stipules (which are often early deciduous) 

 and with small inconspicuous, mostly diclinous flowers. Calyx regular, 

 free from the 1-celled ovary. Stamens as many as the calyx lobes and op- 

 posite to them. Fruit a 1-seeded samara, drupe or acheniurn, separate or 

 aggregated. The following groups have usually b*een regarded as Orders. 



ULMACE^E. Tree* with colorless innoxious jnice. Flowers habitually perfect, not 



in aments. Fruits separate. No albumen. (Figs. 181, 256, 295, 316, 382, 509). . .(a) 

 g ARTOOARPE^E. Trees with milky poisonous juice. Flowers diclinous, in aments 



or heads. Fruits aggregated. Seed albuminous. (Figs. 195-6, 298, 349)... (ft) 

 S URTICE^K. Herbs. Flowers diclinous, not in aments. Filaments crenulate. 



Fertile calyx 3-5-parted. Embryo straight. (Fig. 503). . .(c) 



5g CANNABINE^E. Herbs. Flowers diclinous. Filaments straight. Fertile calyx 

 of 1 sepal, spathe-like. Embryo curved or coiled. (Fig. 213). . .(d) 



a Flowers appearing before the leaves. Fruit a samara winged all around ULMUS. I 



a Flowers with the leaves. Fruit wingless, x a dry nut from a 1-celled ovary. . . PLANERA. 2 



x a sweet, fleshy drupe CKLTIS. 3 



6 Flowers enclosed within a hollow receptacle, both kinds together FICDS. 4 



* Flowers external. y Fertile aments globular. Branches thorny MACLURA. 5 



y Fertile aments globular. Plants thornless BROOSSONKTIA. 6 



y Fertile aments oblong, fruit sweet, juicy MORDS. 7 



c Herbs with stinging hairs. z Stamens 4. Leaves opposite URTICA. 8 



z Stamens 5. Leaves alternate LAPORTEA. 9 



f Herbs stingless. n Stamens 3. Fertile calyx 3-sepalled PILEA. 10 



n Stamens 4. o Flowers in slender spikes BCKHMEUIA. 11 



o Flowers in involucrate clusters PARIETARJA. 12 



d Herbs twining. Fruit in an imbricate strobile-like ament HUMULUS. 13 



d Herbs erect. Fruit a 2-valved caryopsis in axillary pairs CANNABINUM. 14 



1. ULMUS, L. ELM. Fls. $ . Calyx 4-9-cleft. Stam. 49, fil. long 

 and slender. Styles 2. Ovary 2-celled. Samara flat, 1-seeded. 5 Fls. 

 yellowish, or reddish, in. precocious clusters. Figs. 181, 256, 205. 



* Samara fringed .vith hairs, hanging on slender ped., 2-beaked Nos. 13 



* Samara not fringed, nearly sessile, a; slightly notched at apex Nos. 4, 5 



x cleft down to the seed Nos. 6, 7 



1 U Americana L. White Elm. Lvs. oval, acuminate, doubly serrate ; flowers in 

 oose, umbel-like clusters ; fruit oval, 6", its 2 beaks with points incurved and meet- 

 ing. A majestic tree, with ascending branches and often long pendulous " weeping" 

 branchlet*. Native, and everywhere cultivated. 



