Revisions of Some Plant Phyla 35 



ianth and stamens arising below the carpels; (carpels superior). 

 Flowers mostly actinomorphic. 



Order Alismatales. Pistils separate, superior to all other 

 .parts of the flower. 



Family i. Alismataceae. Water Plantains. Aquatic or. palu- 

 dose herbs with mostly radical, often large leaves; flowers small 

 to large; perianth in two whorls of three leaves each (calyx and 

 corolla). Alisma, Sagitfaria. (Pf. II, i, 227.) 



Family 2. Butomaceae. Aquatic or paludose herbs, bearing 

 narrow or broad leaves, with convergent veins; perianth in two 

 whorls, of three leaves each (calyx and corolla). Butonius, Lim- 

 nocharis. (Pf. II, i, 232.) 



Family 3. Truridaceae. Very small, pale, leafless plants grow- 

 ing in wet places in tropical countries. Triuris. (Pf. II, 1,235.) 



Family 4. Scheuchzeriaceae. Aquatic or paludose herbs with 

 rush-like leaves, and small flowers, with a two-whorled perianth, 

 each 4- to 6-parted. Triglochin, Schenchzeria. (Pf. II, i, 222.) 



Family 5. Typhaceae. Cat-tails. Aquatic or paludose herbs, 

 with linear, sheathing leaves; pistil i -celled; ovule i. Typha. 

 (Pf. II, I, 183.) 



Family 6. Sparganiaceae. Aquatic or paludose plants with 

 creeping rootstocks and erect stems, bearing linear leaves ; flow- 

 ers monoecious in dense globose heads. Sparganium. ( Pf . II, 

 I, 192.) 



Family 7. Pandanaceae. Screw-pines. Shrubs or trees with 

 spirally crowded, narrow, stiff leaves on the ends of the branches; 

 pistil i-celled; ovules one or many. Pandanns. (Pf. II, i, 186.) 



Family 8. Aponogetonaceae. Aquatic plants with petioled, ob- 

 long, translucent leaves, with convergent veins ; flowers small, 

 spicate. Aponogeton. (Pf. II, i, 218.) 



Family 9. Potamogetonaceae. River-weeds. Aquatic or palu- 

 dose herbs with mostly alternate stem-leaves ; flowers mostly 

 small and inconspicuous ; perianth none, or of i to 6 leaves in i 



71 



