444 FOURTH GROUP. SEED-PLANTS. 



inferior (Bromeliaceae), elsewhere inferior, usually forming a trilocular capsule or 

 berry ; embryo enclosed in endosperm, by the side of it in Bromeliaceae. Plants of very 

 different habit; strong aerial woody stems with secondary growth in thickness in 

 Dracaena, Aloe, Yucca (belonging to Liliaceae); more often underground rhizomes, 

 tubers, bulbs, from which spring herbaceous annual shoots ; leaves usually narrow and 

 long, in Dioscoreaceae with a broad lamina and slender stalk. 



Families. I. Juncaceae. 5. Taccaceae. 



2. Liliaceae. 6. Haemodoraceae. 



3. Irideae. 7. Pontederiaceae. 



4. Dioscoreaceae. 8. Bromeliaceae. 



Series II. Enantioblastae. 



Flowers in crowded cymose inflorescences (Commelinaceae), inconspicuous (Restiaceae 

 and Eriocauleae) or conspicuous (Xyrideae and Commelinaceae), pentacyclic usually 

 trimerous (Restiaceae and Eriocauleae), often dimerous ; perianth-whorls glumaceous 

 (Restiaceae and Eriocauleae), developed as a calyx and corolla (Xyrideae and 

 Commelinaceae) ; capsule superior, bilocular or trilocular with loculicidal dehiscence ; 

 ovule orthotropous, the embryo (/SXao-rj?) therefore opposite to (eVai/rto?) the base of 

 the seed. Plants with habit of grasses (Restiaceae, Eriocauleae and Xyrideae), or 

 succulent herbs (Commelinaceae). 



Families. I. Restiaceae. 3. Xyrideae. 



2. Eriocauleae. 4. Commelinaceae. 



Series III. Spadiciflorae. 



Inflorescence a spadix or panicle with thick branches (Cyclanthaceae), usually en- 

 veloped in a large sometimes petaloid spathe (Aroideae) ; bracts small or wanting ; 

 perianth never petaloid, usually inconspicuous or abortive (Aroideae, Pandaneae, 

 Typhaceae, Cyclanthaceae) ; flowers frequently unisexual; fruit always superior and often 

 very large (Pandaneae and Palmae) ; seed usually large or very large with copious 

 endosperm, except in Lemnaceae and Naiadaceae; embryo small straight. Plants 

 mostly large and robust, with a strong usually aerial stem and many large leaves with 

 the lamina broad branched or apparently pinnate or flabelliform (Aroideae, Palmae, 

 Cyclanthaceae) and with a stalk and sheath ; without a stalk and very long and narrow 

 (Pandaneae). The Lemnaceae have small branched leafless floating stems (vegetative 

 rhachis) usually with true dependent roots. The Naiadaceae are branched submerged 

 plants with slender stalks and long leaves ; the Lemnaceae and Naiadaceae were 

 formerly grouped together as Centrospermae from the central position of the seed. 



Families, i. Aroideae, including Lemnaceae. 4. Cyclanthaceae. 



2. Pandaneae. 5. Palmae. 



3. Typhaceae. 6. Naiadaceae. 



Series IV. Glumiflorae. 



Inflorescence a spike or panicle without a spathe; flowers very small and incon- 

 spicuous concealed among closely crowded dry bracts (glumes or paleae) ; perianth 

 wanting or replaced by hair-like structures or scales ; fruit superior small dry I -seeded 

 indehiscent; embryo within the base of the endosperm and very small (Cyperaceae) or 

 by the side of the endosperm, largely developed and with a scutellum (Gramineae). 

 Plants with subterranean elongated persistent rhizomes ; aerial shoots erect with long 

 slender internodes and long narrow foliage-leaves in two or three rows (Gramineae). 



Families; I. Cyperaceae. 

 2. Gramineae. 



Series V. Scitamineae. 



Flowers trimerous and zygomorphous or asymmetrical ; both perianth-whorls or 

 the inner only petaloid (Zingibereae and Canneae) ; posterior stamen of the inner 



