Taxonomy Nymphaea amazonum. 



203 



main air-canals, two smaller ones anteriorly and posteriorly, and two still smaller ones 

 beyond these ; one lateral canal on either side of main pair, and numerous smaller ones 

 about; main partitions 2 cells thick; one double bundle anteriorly and one posteriorly 

 and two equidistant from these and from each other on either side; numerous smaller 

 bundles. Idioblasts numerous, all stellate, rather short armed. 



Rhizome (tuber) erect or semi-erect, thick, about 7 cm. long by 3.8 cm. in 

 diameter, brownish-black, apex protected by leaf-bases and long hairs. Phyllotaxy of 

 a high order, the leaf-bases being very close together. Branches several (3 to 5 or 

 6), 7 v 10 cm. long on short stolon-like stalks, produced throughout the season of 

 vegetation, and sending up leaves and flowers among those of the parent plant. 



Geographic Distribution. In still water ; lakes, ponds and ditches. Tropical 

 America between 18 N., 23 S., 38 W., and 78 W., in Jamaica, Guiana, Surinam, 

 Brazil (Para, Bahia, Rio Janeiro). New Granada. Laguna del Corcho, near Ocuiltza- 

 potlan, Mexico. 



= outer whorl. t = staminode. ' = second whorl. 



Number of Floral Organs. 



Measurements of Sepals (in centimeters). 



