Figure 7
Embryonic events during the termination of the chick embryo tail. Embryonic day, E12 to E17 chondrified skeletons (blue) of chick embryos, with ossified cells (red) detectable from E14 to E17. Compare the E17 chondrified skeleton and the adult skeleton showing the fused synsacrum and bony plate in the latter; the 5 free caudal vertebrae and the pygostyle already patterned during somitogenesis.