1. The relationship of clarkias from two continents

   • Peter H. Raven
   • Harlan Lewis

   OriginalPaper Pages: 193 - 205

2. Studies on secotiaceous fungi-IV Gastroboletus, Truncocolumella and Chamonixia

   • Alexander H. Smith
   • Rolf Singer

   OriginalPaper Pages: 205 - 223

3. Studies on secotiaceous fungi-V. Nivatogastrium gen. Nov.

   • Rolf Singer
   • Alexander H. Smith

   OriginalPaper Pages: 224 - 228

4. Studies in saxifragaceae-II. Saxifraga sect. trachyphyllum in North America

   • J. A. Calder
   • D. B. O. Savile

   OriginalPaper Pages: 228 - 249

5. Natural hybridization between silphium laciniatum and silphium terebinthinaceum

   • T. Richard Fisher

   OriginalPaper Pages: 250 - 254

6. A new species of cyperus from the illinois sand prairies

   • Robert H. Mohlenbrock

   OriginalPaper Pages: 255 - 256

7. Errata

   • Margaret Fulford
   • Jane Taylor

   Erratum Pages: 264 - 264