ANALYTICAL KEY. 31 



B. PETALOIDEOUS DIVISION. Flowers not collected on a spadtx, furnished with 

 floral envelopes (perianth) answering to calyx or to both calyx and corolla, either 

 herbaceous or colored and petal-like. 



1. Perianth adherent to the whole surface of the ovary. 

 Flowers dioecious or polygamous, regular. 



Aquatics : ovules and seeds several or numerous. HYDROCHARIDACE^E, 494 

 Twiners : ovules and seeds one or two in each cell. DIOSCOREACE^J, 518 

 Flowers perfect : ovules and seeds usually numerous. 



Stamens only one or two : flower irregular, gynandrous. ORCHIDACE.E, 497 

 Stamens three. 



Anthers introrse, opening transversely. . . BURMANNIACE.E, 496 

 Anthers introrse or versatile, opening lengthwise. HJBMODORACE^, 514 



Anthers extrorse, opening lengthwise IRIDACE.E, 515 



Stamens 6 : flowers usually on a scape from a bulb. AMARYLLIDACEJB, 512 



2. Perianth adherent only to the base or lower half of the ovary. 



Perianth woolly or roughish-mealy : the leaves equitant. H^JMODORACE^E, 514 

 Perianth smooth : the leaves grass-like. Stenanthium, &c., in LILIACEJB, 520 



3. Perianth wholly free from the ovary. 



Pistils numerous or few in a head or ring. . . . ALISMACE.E, 490 

 Pistil one : anthers 1-celled : flowers dioacious. Tendril-bearing. SMILACE^E, 518 

 Pistil one, compound (cells or placenta? mostly 3) : anthers 2-celled. 

 Perianth not glumaceous or chaffy : flowers not in dense heads. 

 ' Stamens 6 (in one Smilacina 4), all alike and perfect. 



Scurfy-leaved epiphyte : seeds hairy- tufted. . . BROMELIACE.SJ, 515 

 Rush-like marsh-herbs : carpels separating closed from the 



axis : seed without albumen. Triglochin, in ALISMACE^E, 490 



Terrestrial, not rush-like : seeds with albumen. 

 Perianth of similar divisions or lobes, mostly colored. ~\ 

 Perianth of 3 foliaceous and green sepals and 3 col- > LILIACE^, 520 



ored withering-persistent petals. Trillium in ) 

 Perianth of 3 persistent green sepals, and 3 epheme- 

 ral deliquescent petals COMMELYNACE^E, 546 



Stamens 6, dissimilar, or only three with perfect anthers. 

 Perianth of 3 herbaceous sepals and 3 unequal 



and ephemeral petals. .... COMMELYNACE^J, 546 



Perianth tubular, 6-lobed PONTEDERIACE^E, 544 



Stamens 3, similar. Moss-like aquatic. Mayaca, tinder XYRIDACE^E, 547 

 Perianth wholly glumaceous, of 6 similar divisions. Rushes. JUNCACE-E, 536 

 Perianth partly glumaceous or chaff-like : flowers in very 



dense heads. Rush-like or aquatic. 

 Flowers perfect : inner perianth of three yellow petals : 

 perfect stamens and plumose sterile filaments each 

 3 : pod 1-celled, many-seeded on 3 parietal placentae. XYRIDACE.E, 547 

 Flowers monoecious or dioecious, whitish-bearded : sta- 

 mens 4 or 3 : pod 2 - 3-celled, 2 - 3-seeded. ERIOCAULONACE^E, 549 





