PALMAE 447 



The staminate flowers of Nipa, Zalacca, and the Mauritiae, for example, 

 are described as lacking all traces of a gynoecium. 



The Perianth. The perianth is usually inconspicuous; staminate flowers 

 are sometimes showy; calyx and corolla are much alike but distinguish- 

 able as inner and outer series of three organs. Sepals and petals are 

 persistent, enlarging after flowering and becoming leathery or hard, 

 sometimes partly fleshy. In die fruit, they form, with bracts, a basal 

 cupule. Rarely, the perianth is rudimentary or absent — Nipa. 



The Androecium. The stamens are commonly six, in two series, but 

 there is considerable variation; when more — thirty-five to fifty, up to 

 one hundred, and more than one hundred — they have been described 

 as in whorls of three, but otlier descriptions are "in a fascicle" and "in 

 one series." Where there are numerous stamens, many may be sterfle. 

 Rarely, there are only three stamens, as in Nipa, Areca triandra. In 

 androecia with only three stamens, the inner of the two ancestral whorls 

 appears to have been lost in reduction. In dicotyledons, similar reduc- 

 tion in stamen whorls is by loss of the outer whorl. The filaments 

 range from narrowly laminar to terete and slender, and are often broad 

 at the base. The anthers are chiefly introrse. Connation of filaments is 

 frequent, and the whorls may be independent or united. Adnation of 

 stamens to perianth and to gynoecium is frequent. 



The Gynoecium. The gynoecium consists of three — rarely four to 

 seven — carpels, free or connate in various degrees. Complete apocarpy 

 is rare — Chamaerops, Trachijcarpus — and perhaps present only in fully 

 bisexual flowers. (Vestigial carpels are commonly free.) In syncarpy, 

 connation varies in extent and in place of fusion; in some taxa, fusion 

 is distal or proximal only. Frequently, the tip of the receptacle pro- 

 jects between the carpel bases, and the carpel bases may be fused to it 

 laterally, as in some dicotyledonous families. All steps in the evolution 

 of septal nectaries are shown — from mere secretory areas to enclosed 

 glands with "canals" to apertures on the upper surface of the ovary. 

 (The story here parallels that in the Liliaceae; septal glands have de- 

 veloped independently, perhaps several times.) The stigmas are usually 

 sessile; a few genera have short styles. 



The Ovule. Each of the carpels bears one "basal" ovule, but only one 

 ovule becomes a seed, even in apocarpous taxa. In syncarpy, two of the 

 three ovules begin to degenerate at flowering time, and, as the fruit de- 

 velops, the sterile carpels are compressed and enter into the formation 

 of the wall of the fruit, with the position of their locules apparent in 

 the wall, as in the coconut (Fig. 93). The ovules are basically anat- 

 ropous; the massive funicle and integuments and crowding in the 

 small ovarian cavity distort their form. The ovules are subbasal and 



