Fig. 6.

Technovit sections of Xenopus laevis embryos at early gastrula (a), mid-gastrula (b), late gastrula (c, d), early neurula (e–g) and tailbud stage (h) at levels shown in Fig. 3. Labeling: ec midline neuroectoderm, am axial mesoderm, se superficial ectoderm, pam preaxial mesoderm (leading edge), s somites, nt neural tube. Intersecting arrows in indicate anatomical axes: A animal, Veg vegetal, L left, R right, D dorsal, V ventral