THALAMIFLOR^ 183 



Nat. Order 12. Nymphceacece. — Perennial aquatic 

 herbs with rhizomes embedded in the mud. Flowers 

 solitary, on a naked scape. Leaves often peltate, 

 floating. Perianth of many spirally-imbricated seg- 

 ments passing gradually from sepals to petals and 

 from petals to stamens. Stamens many, the inner or 

 all perigynous or some epigynous, adherent to the 

 fleshy cup-shaped thalamus, which envelops and ad- 

 heres to the pistil. Carpels usually adherent to the 

 cup-shaped thalamus as a many-celled ovary; stigmas 

 sessile, radiating; ovules mostly scattered on the wall 

 of the ovary, but not under the ventral suture (super- 

 ficial placentation). Fruit a fleshy berry-like mass. 

 Seeds arillate or not, with both perisperm and endo- 

 sperm (vitellus). Distribution both temperate and 

 tropical. 



Common plants are shalook (figs. 76 and 104), 

 rakta-kambal, and nil-padma {Nymphcea Lotus, N. 

 rubra Roxb., and N. stellata). Euryale ferox of East 

 Bengal-tanks is known by the name of kanta-padma 

 for its spinous leaves and fruits; the leaves are often 

 4 feet across. The NympJicBa have homogamous 

 conspicuous pollen-flowers. Victoria regia, a South 

 American species, is well known for its floating or- 

 bicular leaves, often rneasuring 12 feet across, and 

 flowers about i foot across, and is comparable with 

 E. ferox. A specimen of this may be seen in the 

 Royal Botanical Gardens, Calcutta (Sibpur). The 

 structure of the rhizome is more of a Monocotyledon- 

 ous type, and the habit is that of Hydrocharidacece. 



Nat. Order 13. Nelumbiacecs. — Similar to Nym- 

 pfueacecB, with the following points of difference: 

 (i) Leaves rise above the surface of the water; (2) 

 perianth with 4 to 5 sepals, many petals, all caducous; 

 (3) stamens hypogynous, caducous; (4) carpels many. 



