Typification of Six Robert Brown Brassicaceae Names from Arctic North America

Typifications are made for six taxa in the Brassicaceae described by Robert Brown from plants collected in arctic North America. The taxa were published in his 1823 preprint <i>Chloris Melvilliana</i>, which in 1824 appeared as the botanical appendix to William E. Parry's <i>Supplement to the Appendix of Parry's First Voyage</i>. Lectotypes are selected for <i>Eutrema edwardsii</i> R. Brown, <i>Parrya arctica</i> R. Brown, <i>Parrya macrocarpa</i> R. Brown, <i>Platypetalum</i> R. Brown, and <i>Platypetalum pur- purascens</i> R. Brown, and a neotype is selected for <i>Platypetalum dubium</i> R. Brown.