Fig. 4.

Light micrographs of micropylar and chalazal regions of seeds of G. carolinianum allowed to imbibe methylene blue for different periods of time: (A) and (B) surface view of chalazal end of a seed before and 1·5 h after imbibition; (C) longitudinal section through chalazal region 1·5 h after imbibition; (D) chalazal region of a seed 1·5 h after imbibition (palisade layer removed to expose subpalisade layer); (E) micropylar region of a seed after 10 min imbibing the dye (hinged valve removed); (F) micropylar region of a seed after 30 min (palisade layer removed to expose elongated subpalisade layer). Abbreviations: Ch, chalaza; Chp, chalazal plug; Em, embryo; Mi, micropyle; Pa, palisade cells; Spa, subpalisade cells; SpaL, elongated subpalisade cells of micropylar region; Wg, water gap.