Fig. 3.

Expression of Indian hedgehog (ihh) and desert hedgehog (dhh) in the chick. a, b whole-mount views of ihh expression at HH stage 4 (a) and 7 (b). c transversal technovit section of embryo shown in b; d ihh expression in the gut endoderm (HH stage 17); whole-mount view (e) and section (f) of dhh expression in the dorsal part of intermediate mesoderm (HH stage 11); f dhh expression in the mesonephric tubules (HH stage 17). N notochord, fp floor plate, im intermediate mesoderm, s somite, vv vitelline vein, md mesonephric duct, mt mesonephric tubule, arrowhead—position of the node