Houstonia purpurea, spec. nov.

2. Houstonia foliis ovato-lanceolatis, corymbis terminalibus. Gron. virg.15.

Rubia mariana, alsines majoris folio ad caulem binato, flore purpuro-rubente. Pluk. mant. 164. Raj. suppl. 262.

Habitat in Virginia.