[For Franz Gabriel de Bray, 1765-1832, French ambassador to Bavaria, head of Regensberg Botanical Society]

James G. Harris

Platypetalum R. Brown

Perennials; (sometimes pulvinate, caudex simple or many-branched); scapose or not; usually pubescent or pilose, sometimes glabrous, trichomes short-stalked, forked, subdendritic, or submalpighiaceous, mixed with simple ones (rarely exclusively). Stems erect to decumbent or ascending, unbranched or branched. Leaves basal and, sometimes, cauline; petiolate or sessile; basal rosulate, petiolate, blade margins entire, sinuate, dentate, or, rarely, pinnately lobed; cauline usually absent, rarely few present, (sub)sessile, blade margins usually entire, rarely dentate or pinnately lobed. Racemes (corymbose, sometimes bracteate basally or throughout), elongated or not in fruit. Fruiting pedicels erect, divaricate, or ascending, slender (much narrower than fruit). Flowers: sepals [sometimes persistent], oblong [ovate], lateral pair not saccate basally (sometimes slightly so in B. humilis and B. linearis); petals white, pink, or purple [rarely pale yellow], obovate, oblanceolate, or spatulate, (slightly to much longer than sepals), claw distinct or not, (shorter than sepal, apex obtuse or rounded); stamens tetradynamous; filaments dilated or not basally; anthers ovate or oblong, (apex usually obtuse, sometimes apiculate); nectar glands (4), lateral, 1 on each side of lateral stamen. Fruits siliques or silicles, sessile, linear, oblong, cylindrical, oval-elliptic, ovoid, lanceoloid, lanceoloid-subulate, or globose, smooth or torulose, terete or slightly latiseptate; valves each often with prominent midvein, glabrous or pubescent; replum rounded; septum complete, (membranous, translucent); ovules (5-)14-44 per ovary; stigma capitate, entire or slightly 2-lobed. Seeds plump, not winged, oblong or ovoid; seed coat (minutely reticulate), not mucilaginous when wetted; cotyledons incumbent. x = 7.

Species 17 (7 in the flora): North America, n Europe, Asia.

SELECTED REFERENCES Abbe, E. C. 1948. Braya in boreal eastern America. Rhodora 50: 1-15. Harris, J. G. 1985. A Revision of the Genus Braya (Cruciferae) in North America. Ph.D. thesis. University of Alberta. Parsons, K. A. 2002. Reproductive Biology and Floral Variation in the Endangered Braya longii and Threatened B. fernaldii (Brassicaceae): Implications for Conservation Management of Rare Plants. M.S. thesis. Memorial University of Newfoundland. Warwick, S. I. et al. 2004. Phylogeny of Braya and Neotorularia (Brassicaceae) based on nuclear ribosomal internal transcribed spacer and chloroplast trnL intron sequences. Canad. J. Bot. 82: 376-392.