Texture rendering of three-dimensional Surface Imaging Microscopy (SIM) date acquired in a fixed late gastrula stage Xenopus laevis embryo. The rendering at center has been section to show the internal surfaces of the blastocoel and archenteron. The surrounding images show central coronal, sagittal, and equitorial sections through the same date. The original SIM spatial resolution was approximately 1.7 microns in each dimension. See Tyszka et al., Developmental Dynamics 234:974–983. © 2006 Wiley-Liss, Inc.