1. Editorial

   • K. Sander

   EditorialNotes Pages: 375 - 375

2. On the origin of the yolk protein ferritin in snails

   • Werner Bottke
   • Monika Burschyk
   • Jutta Volmer

   OriginalPaper Pages: 377 - 382

3. Induced neuroma formation and target muscle perturbation in the giant fiber pathway of the Drosophila temperature-sensitive mutant shibire

   • Margaret Raper Hummon
   • Walter J. Costello

   OriginalPaper Pages: 383 - 393

4. The factors that promote the development of symmetry properties in aggregates from dissociated echinoid embryos

   • Gary Freeman

   OriginalPaper Pages: 394 - 405

5. Developmental pattern and molecular identification of globin chains in Xenopus laevis

   • E. Sandmeier
   • D. Gygi
   • R. Weber

   OriginalPaper Pages: 406 - 412

6. Reversible commitment of neural and epidermal progenitor cells during embryogenesis of Drosophila melanogaster

   • Gerhard M. Technau
   • Thomas Becker
   • Jose A. Campos-Ortega

   OriginalPaper Pages: 413 - 418

7. The determination of sense organs in Drosophila: interaction of scute with daughterless

   • Christine Dambly-Chaudière
   • Alain Ghysen
   • Yuh Nung Jan

   OriginalPaper Pages: 419 - 423

8. The reinforcement-extinction process of selector gene activity: a positive feed-back loop and cell-cell interactions in Ultrabithorax patterning

   • Juan Botas
   • Carlos V. Cabrera
   • Antonio Garcia-Bellido

   OriginalPaper Pages: 424 - 434

9. Genetic interaction between homoeotic Sex combs reduced and Regulator of bithorax (or trithorax) genes of Drosophila melanogaster

   • Takashi Sato

   OriginalPaper Pages: 435 - 440

10. Mesoderm induction in the future tail region of Xenopus

    • H. R. Woodland
    • E. A. Jones

    OriginalPaper Pages: 441 - 446