ORDER CXIX. SMILACEtE. 517 



MONOCOTYLED'ONiE. 



Trunk usually cylindrical, with no distinction of pith, wood, 

 and bark. Leaves with simple, parallel veins running from the 

 base to the apex of the leaf, usually alternate. Embryo with 1 

 cotyledon, or if more than 1, alternate. Radical inclosed in a 

 sheath, through which it bursts in germination. 



I. DICTYOGEN'EJE. 



(From dicfoion, a net, and gennain, to produce, the leaves being net-veined.) 



Monocotyledonous plants, with reticulated veined leaves, and 

 with the roots resembling, in some respects, dicotyledons. 



Order CXVIIL— DIOSCOREA'CEtE. {Yam Tribe) 



Flowers dioecious. Perianth superior, 6-cleft, equal. Sta- 

 mens 6, inserted into the base of the perianth. Ovary 3-celled, 

 with 1 — 2 ovules in a cell. Style deeply 3-parted. Stigmas 

 simple. Fruit a thin, compressed capsule. Seed flat. Em- 

 bryo small. Twining, herbaceous plants, with reticulated 

 leaves. 



Genus I.— DIOSCORE'A. L. 20—6. 

 (From Dioscorides, a Greek physician.) 



Genus same as the Order. 



1. D. villo'sa, (L.) Stem herbaceous, climbing over shrubs, terete. 

 Leaves alternate, opposite, and verticillate ; the lower verticillate, the 

 upper alternate, cordate, acuminate, 9-nerved, pubescent beneath. 

 Sterile flowers in axillary panicles, small; fertile flowers in simple ra- 

 cemes. Styles 3. Capsule 3-celled, 3-winged, 2-seeded. — White. 2+. 

 May — July. Sandy soils. Common. 10 — 12 feet. Yam-root. 



2. D. quaterna'ta, (Walt.) Stem climbing. Leaves verticillate or 

 alternate, cordate, acuminate, glabrous, 7 -nerved ; lateral nerves bifid. 

 —White. If. July. Old fields. 6—8 feet. 



Order CXIX.— SMILA'CE^E. (Sarsaparilla Family.) 



Flowers dioecious or perfect. Perianth petaloid, 4 — 6-parted. 

 Stamens 4 — 6, inserted into the base of the perianth. Ovary 

 3-celled, 1 or many seeded. Style usually 3-parted. Stigmas 

 3. Fruit baccate. Seeds with a membranaceous testa, shrub- 

 by or herbaceous, often climbing. Leaves reticulated. 



