96 



ORDER CXVII. LENTIBULARINE.E. 



A small Order including 4 genera, two only of which are repre- 

 sented in Natal. The genus Utricularia, which is by far the largest 

 genus of the four, takes its name from the bladder-like organs usually 

 found on the submerged leaves of the completely aquatic species. Of 

 these organs De Candolle says: "These bladders are rounded and 

 furnished with a kind of movable operculum. In the young plant 

 they are filled with a mucus heavier than water, and the plant, sub- 

 merged l)y this ballast, remains at the bottom. Towards the flowering 

 season the leaves secrete a gas which enters the utricles, raises the 

 operculum and drives out the mucus, when the plant, now furnished 

 with aerial bladders, rises slowly and floats on the surface, and then 

 flowers. This accomplished, the leaves again secrete mucus, which 

 replaces the air in the utricles, and the plant redescends to the bottom 

 and ripens its seeds in the place where they are to be grown." (De 

 Candolle.' Vegetable physiology). Some, however, of our indigenous 

 species are found on moist rocks and similar places, where there is 



