1. Illiger and the biological species concept

   • Ernst Mayr

   OriginalPaper Pages: 163 - 178

2. Agassiz, Mendel, and Heredity

   • J. A. Weir

   OriginalPaper Pages: 179 - 203

3. The role of Liberty Hyde Bailey and Hugo de Vries in the rediscovery of Mendelism

   • Conway Zirkle

   OriginalPaper Pages: 205 - 218

4. Mendel's program for the hybrization of apple trees

   • V. Orel
   • M. Vávra

   OriginalPaper Pages: 219 - 224

5. Studies of animal populations from Lamarck to Darwin

   • Frank N. Egerton

   OriginalPaper Pages: 225 - 259

6. Wallace, Darwin, and the theory of natural selection

   • Barbara G. Beddall

   OriginalPaper Pages: 261 - 323

7. Notes on source materials: The Edwin Grant Conklin papers at Princeton University

   • Garland E. Allen
   • Dennis M. McCullough

   OriginalPaper Pages: 325 - 331

8. The J. H. B. bookshelf

   • Judith P. Swazey

   OriginalPaper Pages: 333 - 340