DIANDRIA. MONOGYNIA. 19 



TheLemnas are minute aquatic plants, of an extremely 

 simple structure, composed at most, of 3 or 4 lenticular 

 leaves, lateral!}' adnaie and proliferous, rarely fiovcrmg. 

 Each leaf as a perfect plant, in aggregation, produces a 

 single floating radicle, or, in some species, a small bun- 

 dle ot fibres. 



SpELCiEs. l.mmor. 2. ^Ibba. 5. ^Aerma'/s, of Beauvois. 

 4? trisulca. (1 lie genus of this plant is doubtful.) 



Obs. Like many other aquatic plants the Lemnas are 

 common to ahnost every country and clinnate; they even 

 vegetate in the warmest thermal springs. 



