A STUDY OF THE STRUCTURE OF THE GYNOECIUM OF NELUMBO LUTEA (WILLD.) PERS

In the course of time the genus Nelumbo has repeatedly been given a different taxonomic status. Dumortier (1829) and Lind ley (1836) raised Nelumbo, previously included in the Nymphaeaceae, to the rank of a separate family Nelumbonaceae. Their views have only recently found recognition. Li (1955) considered Nelumbo to be so aberrant that he proposed a separate order Nelumbonales for this genus, which, according to Takhtajan (1959), is also accepted by Snigirewskaya. As the principal differences between Nelumbo and the Nymphaeales Takhtajan mentions the tricolpate pollen grains, the morphology of the gynoecium, the absence of a suspensor and of perisperm, the large, massive embryo with semiglobose cotyledons, the presence of a special “respiration pore”, the green plumule, the lack of ideoblasts and the different basic chromosome number. In Takhtajan’s classification the Polycarpicae are treated as a super-order, consisting of the orders Magnoliales, Laurales, Piperales, Aristolochiales, Nymphaeales, Nelumbonales, Illiciales, Ranales, Papaverales en Sarraceniales. Hutchinson (1958), on the other hand, includes Nelumbo in Nymphaeaceae. The first ontogenetic studies were made by Baillon (1871) who described the emergence of what he called “la feuille carpellaire” and already mentioned the occasional occurrence of petaloid stamens of which I have also found some striking examples. Strasburger (1887) considered the gynoecium of Nelumbo to consist of monocarpellate apocarpous carpels which during their ontogeny sink into the hypanthium. Troll (1933, 1934a, 1934b) examined Nelumbo nucifera (sub speciosum) in connection with his theory of the peltate carpel and called the placentation “laminal-median”.