1. The maritime species of Abronia (Nyctaginaceae)

   • Stephen Szlatenyi Tillett

   OriginalPaper Pages: 299 - 327

2. Two species of Stereum, one old, one new

   • A. L. Welden

   OriginalPaper Pages: 328 - 332

3. Analysis of chemical and morphological variation in the Ramalina siliquosa species complex

   • William Louis Culberson

   OriginalPaper Pages: 333 - 352

4. A revision of Solanum sect. Brevantherum (Solanaceae) in North and Central America

   • Keith E. Roe

   OriginalPaper Pages: 353 - 373

5. Interspecific hybridization and its evolutionary significance in the genus Aquilegia

   • Ronald J. Taylor

   OriginalPaper Pages: 374 - 390

6. A new species of Polymnia (Compositae: Heliantheae) from Mexico

   • James R. Wells

   OriginalPaper Pages: 391 - 394