4. Nymphaea jamesoniana Planchon, Fl. Serres Jard. Eur. 8: 120. 1852.
Rhizomes branched or unbranched, erect, ovoid to cylindric; stolons absent. Leaves: petiole glabrous. Leaf blade abaxially and adaxially green, sometimes with darker flecks, elliptic, 8-25 × 7-19 cm, margins entire; venation conspicuously weblike centrally with cross veins between major veins, principal veins 11-17; surfaces glabrous. Flowers floating, 7-15 cm diam., opening and closing nocturnally, sepals, petals, and outer stamens in distinct whorls of 4; sepals uniformly green, obscurely veined, lines of insertion on receptacle not prominent; petals 12, 16, or 20, outer greenish at least abaxially, inner creamy white; stamens 35-85, creamy white, connective appendage projecting to 1 mm, rarely more, beyond anther; filaments widest below middle, longer than anthers; pistil 19-33-locular, appendages at margin of stigmatic disk slightly club-shaped, 3-7(-9) mm. Seeds nearly globose, 0.5-0.8 × 0.45-0.7 mm, 1.1-1.2 times as long as broad, with scattered papillae 10-50 µm. 2 n = 28.
Flowering late summer-fall. Shallow water of mostly temporary ponds or ditches; 0-100 m; native, Fla.; Mexico; Central America; South America.
All material of the predominantly neotropical Nymphaea subg. Hydrocallis in the flora is referable to this taxon. D. B. Ward (1977b) and others listed N . blanda G. Meyer [= N . glandulifera Rodschied], a Central and South American taxon, for Florida.