866 



XLVI. PONTEDEEIAOE^E. 



Pontederia. 



Transverse section of 



fruit (mag.). 



Pontederia cordata. 



Pontederia. 



Perianth and androeciam 



laid open. 



Pontederia. 



Vertical section of 



fruit (mag.). 



Pontederia. 

 Embryo 

 (mag.). 



oval, orbicular, or sub-cordate, with arched nerves ; sometimes replaced by a petiolar 

 phyllode representing a leaf with parallel nerves (Heteranthera). INFLORESCENCE 

 axillary or sub-terminal. FLOWEBS in a spike or panicle, ebracteate, usually sessile. 

 PEEIANTH inferior, petaloid, glandular, or hairy outside, usually white, blue or 

 violet, infundibular or hypocrateriform ; tube more or less elongated; limb 6-partite; 

 segments unequal, obscurely 2-seriate, the inner median superior and larger ; 2-labiate- 

 ringent, spirally rolled in aestivation, marcescent or succulent. STAMENS inserted 

 on the tube or throat of the perianth, sometimes 6, opposite to the 6 perianth- 

 segments; sometimes 3, opposite to the inner segments, the anterior usually 

 dissimilar; filaments filiform, arched, sometimes thickened in the middle; anthers 



