222 ALLIANCES OF PLANTS. 



GROUP IV. RETOS^E. 



Flowers unisexual. Ovary 253. Dioscoreaceae . Nauseous ; some- 

 inferior times eatable 



(Yam). 



Flowers hermaphrodite. 254. Smilaceae . Diuretic; demul- 

 Ovary superior. cent (Sarsapa- 



rilla). 



Flowers binary, highly de- 255. Roxburghiaceae. 

 veloped. 



GROUP V. SPADICOS^E. 



Alliance 1. Pandales. Flowers on a spadix. Fruit drupa- 

 ceous. 



Flowers spiral. Spires al- 256. Cyclanthaceee. 

 ternately male and fe- 

 male. 



Flowers achlamydeous and 257. Pandanacese . Fruit eatable, 

 apocarpous. 



Alliance 2. Arales. Flowers on a spadix. Fruit either 

 berried or capsular. 



Flowers unisexual . .258. Araceae . . Acrid. Poisonous. 

 Flowers hermaphrodite . 259. Acoracese . Aromatic. 



Alliance 3. Typhales. Flowers on a spadix. Sepals three. 

 Anthers clavate. 



260. Typhaceae . Of no importance. 



Alliance 4. Flumales. Flowers in spikes, or solitary. 



Floaters. Ovules pendu- 261. Naiadacese . Unimportant. 



lous. 



Terrestrial. Ovules erect 262. Juncaginaceae. 

 Floaters, with none, or 263. Pistiacese . Acrid (Duck-weed). 



scarcely any, axis of 



growth. 



It is here that we find a transition to Rhizanthae in the case of the genus Lemna, 

 which is destitute of vascular system, and is the lowest known form of Endows. Ty- 

 phaceae connect this group with Glumosae, and Pandales with Epigynosse. 



