Frommia H.Wolff

Perennial herb. Leaves pinnate, the pinnae sessile, repeatedly 2–3-forked into crowded, very narrow linear-canaliculate segments, the leaves thus having the appearance of leaves of Ceratophyllum demersum, predominantly basal. Umbels numerous, compound, pedunculate, with neither involucre nor involucel. Flowers polygamous. Calyx-teeth obsolete. Petals small, yellow, glabrous, incised above with a sharp incurved lobule. Fruit somewhat laterally compressed, glabrous, ovoid, the mericarps slightly narrowed to the commissure; primary ribs low, not at all prominent; valleculae 3-vittate, the commissure 4–6-vittate, vittae often ± merging when the fruit is ripe; stylopodia conical, styles short and rather thick; carpophore very deeply bifid. Endosperm oblong-reniform in section.