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Amsterdam SUMMARYThe ovules and seeds of the genera Geranium, Pelargonium, Erodium, Monsonia, and Sarcocaulon are very similar. The ovule primordium of Geranium is trizonate. The outer and inner integuments are both of dermal derivation and initially only 2 cells thick, to become multilayered owing to mitotic activity in the inner cell layer. Shortly before fertilisation a development begins which ultimately results in a marked degree of campylotropy of the seeds. The mechanical layers consist of the sc1erotisedand crystal-containing cells ofthe inner epidermis of the outer integument, and sclerotised cells of the outer layer of the inner integument which are star-shaped in surface view. Nucellus and endosperm have disappeared almost completely in the mature seed. In several representatives of the family the seed-coat contains stomata.

No abstract

Trigonia cipoensis has a trizonate ovule primordium. The mature ovule is anatropous, bitegmic and tenuinucellate. Both integuments are of dermal origin; the inner integument is strongly multiplicative, especially after fertilisation. The mature seed is densely covered by cottony testal hairs. Of the inner integument the outer layer develops into a lignified, fibrous exotegmen, whereas the inner layer is tanniniferous. Endosperm formation is initially nuclear, the tissue later becoming cellular throughout. Ovule and seed structure indicates a relationship with the Linales and not with the Polygalales with which the family Trigoniaceae is ususally associated.