Movie 1.

The mesectoderm separates the mesoderm (ventral) from the ectoderm (lateral) on both sides of the ventral midline. Mesectoderm and ectoderm cells in a Drosophila embryo expressing E-cadherin:GFP. Mesectoderm cells are highlighted in blue. Time is with respect to the completion of mesectoderm divisions. Anterior, left. Images were acquired every 5 minutes.