124 DICOTYLEDONOUS PLANTS. 



ORDER XLIV. PODOSTEMEjE. Lind. 



Flowers naked, monoclinous, bursting through an irregu- 

 larly lacerated spathe. Stamens hypogynoua, varying from 

 2 to an indefinite number, monadelphous, alternately sterile 

 and shorter. Ovary, free, spuriously 2-celled ; ovules nu- 

 merous ; styles two or none ; stigmas 2 -or 3. Fruit slightly 

 pedicillate, capsular, opening by two valves, which fall off 

 from the dissepiment which is parallel with them. Seeds 

 numerous, minute, their structure unknown, or according to 

 Von Martius, entirely simple. 



Herbs with floating stems. Leaves cnpillary or linear, or 

 irregularly lacerated, or minute and imbricated. Flowers mi- 

 nute. 



1. PODOSTEMUM. Mich. 



Monoecious. Calyx and corol none. Stamens 2, affixed 

 to a common pedicel. Germ ovate. Stigma 1, sessile. Cap- 

 suh 2-celled, 2-valved, many-seeded. Seeds minute. 



Monoeda. Diandria. 

 P. ceratophyUum Mich. 



HAB. Rocks in streams. Del. to Car. July. I/. Stem fili- 

 form, floating. Leaves pinnate. Flowers axillary. 



ORDER XLV. CERATOPHYLLE.E. De Cand. Lind. 



Flowers monoecious. Calyx inferior, ninny-parted. Sta- 

 mens 12 20 ; Jilaments wanting ; anthers 2-celled. Ovary 

 superior, 1-celled ; ovule solitary, pendulous ; stigma filiform, 

 oblique, sessile. Nut 1-celled, 1-seeded, indehiscent, termi- 

 nated by the hardened stigma. Seed pendulous, solitary ; al- 

 bumen none ; embryo with 4 cotyledons, alternately smaller ; 

 plumnla many-leaved ; radicle superior. 



Floating herbs with multifid cellular leaves. 



1. CERATOPHYLLUM. Linn. 



Monoecious. Calyx many-parted. STERILE FL. Corol 

 none. Stamens 16 20 ; anthers tricuepidate. FERTILE FL. 

 Corol none. Style 1, filiform. Nut 1-seeded. 



Monoeda. Polyandria. 

 C. demcrsum Linn. : fruit armed with 3 spines. 



