TABLE OF CONTENTS 



INTRODUCTION 1 



ARACEAE 2 



Acorus 2 



Acorus calamus 2 



Orontium 3 



Orontium aquaticum 3 



Peltandra 3 



Peltandra virginica 3 



Calla 3 



Calla palustris 7 



Symplocarpus 7 



Symplocarpus foetidus 7 



Selected References 7 



LEMNACEAE 12 



Wolffia 12 



Key to Species 12 



Wolffia Columbiana 14 



Wolffia borealis 14 



Wolffia brasiliensis 14 



Wolffiella 16 



Wolffiella gladiata 16 



Spirodela 16 



Spirodela polyrhiza 16 



Lemna 16 



Key to Species 18 



Lemna trisulca 18 



Lemna ualdiuiana 18 



Lemna perpusilla 19 



Lemna minor 19 



Literature Cited and Selected References 19 



XYRIDACEAE 23 



Xyris 23 



Key to Species 23 



Xyris torta 24 



Xyris montana 24 



Xyris difformis 24 



Xyris smalliana 34 



Literature Cited and Selected References 34 



ERIOCAULACEAE 34 



Eriocaulon 34 



Key to Species 34 



Eriocaulon parkeri 35 



Eriocaulon septangulare 35 



Selected References 35 



PONTEDERIACEAE 35 



Pontederia 38 



Pontederia cordata 38 



11 



