XVI International Botanical Congess

Two Roridula species distinguished by shape, surface and exotesta structure. R.dentata had ellipsoidal seeds with reticulate surface. Exotesta cells were filled with mucilage and had very thick lignified inner periclinal walls (IPW) and the basal part of anticlinal walls (AW), all with a lot of branched pores. The upper part of AW and the outer periclinal walls (OPW) were thin. R.gorgonias had polyhedral seeds with irregular thorn-like surface. Exotesta cells had very thick not lignified IPW and the base part of AW with pores, the upper part of AW and OPW were thin. Inside and outside of exotesta cells were found the small brown globules, probably, of lipoprotein nature. Two species, certainly, were closely related, because their seeds had similar walls thickness in exotesta cells and other seed coat layers, the hypostase, the epistase, embryo structures and storage substances.