1. Aneuploidy disrupts embryogenesis : Theodor Boveri's analysis of sea urchin dispermy

   • Klaus Sander

   Essay Pages: 247 - 247

2. Neurulation in the anterior trunk region of the zebrafish Brachydanio rerio

   • Beate Schmitz
   • Cyrus Papan
   • José A. Campos-Ortega

   Original Articles Pages: 250 - 259

3. Molecular specification of cell lines in the embryo of Platynereis (Annelida)

   • Adriaan W. C. Dorresteijn
   • Brian O'Grady
   • Yolande Boilly-Marer

   OriginalPaper Pages: 260 - 269

4. Competence of blastomeres for the expression of molecular tissue markers is acquired by diverse mechanisms in the embryo of Platynereis (Annelida)

   • Adriaan W. C. Dorresteijn
   • Christiane Graffy

   OriginalPaper Pages: 270 - 275

5. Genes required for embryonic muscle development in Drosophila melanogaster A survey of the X chromosome

   • Rachel Drysdale
   • Emma Rushton
   • Michael Bate

   Original Articles Pages: 276 - 295

6. Quantitative analysis of mid-gestation mouse aggregation chimaeras: non-random composition of the placenta

   • Roberta James
   • Jean H. Flockhart
   • John D. West

   OriginalPaper Pages: 296 - 305

7. Effect of otu mutations on male fertility and spermatogenesis in Drosophila melanogaster

   • M. Tirronen
   • T. I. Heino
   • Ch. Roos

   Short Communication Pages: 306 - 311