THE VEGETABLE KINGDOM. 



305 



here and there little vesicular leaves, representing so many 

 utricles in miniature, the gaping mouths of which seem to 

 be guarded by two prominent filaments. So long as ever 

 the Utricularia is only occupied in providing for its own 

 subsistence, these vesicles remain filled with a mucous 

 fluid, the Aveight of which overloads them, and the plant, 

 borne down in this way, rests supported on the bot- 

 tom of the pond, to which, however, it in no way 

 adheres. 



But later on, when the period of floAvering arrives, the 

 vesicles absorb the mucus which filled them, and replace 



258. Branch of the Utricidaria laden with its Hydrostatic Vesicular Leaves. 



it with an aeriform fluid. Then the plant, having become 

 lighter than the water, escapes from the bottom and rises 

 to the surface, where it floats and where its pretty golden 

 yellow floAvers are expanded and fecundated. 



After this, by an unexpected reflex action, and A\dien 

 the torches of Hymen are scarcely extinguished, tlic vesi- 

 cles expel the gas which they contain and fill ancAv Avith 

 Aveighty mucus. At this last moment the Utricularia 

 falls again to the depths of the marsh, Avhere the spouses 

 expire in the act of ripening their fruits. 



A more robust plant, the Aldrovanda, AAdiich groAvs in 



