Cover picture: The cortical hem is a medial source of BMP and WNT signaling molecules that pattern the embryonic cerebral hemisphere. The cortical antihem is an EGF family signaling source located mirror-image to the cortical hem along the lateral edge of the embryonic crebral cortex. Embryonic day 12.5 mouse cerebral hemisphere was processed for Sfrp2 gene expression to demonstrate the antihem. This image was produced with Adobe Photoshop Extrude filter. For details, see the article by Assimacopoulos et al. in this issue (pages 6399–6403).