ANALYTICAL KEY. 
XXIX 
Flowers monoecious, and quite destitute of floral envelopes. 
TyPHACEjE. 
Flowers perfect, on a lateral spadix ; sepals o. Acorus, in Arace^e, 93 
Terrestrial or marsh plants ; leaves mostly with a distinct 
netted-veined blade, petioled. .... Arace^e, 92 
B. Petaloideous Division. Flowers not collected on a spadix, fur- 
nished with floral envelopes {perianth), answering to calyx or to both 
calyx and corolla, either herbaceous or colored and petal-like {wholly 
glumaceous in Juncacece). 
1. Perianth adhering to the whole surface of the ovary. 
Flowers dioecious (or rarely perfect), regular. 
Aquatics; ovules and seeds several or numerous. 
HYDROCHARIDACEiE. 
Twiners; ovules and seeds one or two in each cell. Dfoscoreaceae, 88 
Flowers perfect; ovules and seeds usually numerous. 
Stamens only one or two; flowers irregular, gynandrous. 
ORCHIDACE.E, 86 
Stamens three. 
Anthers extrorse, opening lengthwise. . . Iridace/E, 88 
Stamens six ; flowers usually on a scape from a bulb. 
Amaryllidacea-:, 88 
2. Perianth adhering to the base or loioer half of the ovary. 
Perianth woolly or roughish-mealy ; leaves often equitant. 
PI .E M AIM (RACE vE, 
Perianth smooth, the leaves grass-like. 
Stenanthium, &c., in Liliace^e. 
87 
3. Perianth wholly free from the ovary. 
Pistils numerous or few in a head or ring. . . Alismace^e, 94 
Pistil one, compound (cells or placentae mostly three). 
Perianth not glumaceous or chaffy, flowers not in dense heads. 
Stamens (in Maianthemum 4), similar and perfect. 
Marsh herbs; carpels nearly distinct or serrating closed from 
the axis, seed without albumen. Juncagineae in Najadaceal 
Terrestrial, not rush-like ; seeds with albumen. 
Perianth of similar divisions or lobes, mostly colored. 
LlLIACEiE, 89 
Perianth of 3 foliaceous and green sepals and 3 colored 
withering-persistent petals. . . Trillium in Liliace/e, 91 
