Three-dimensional visualization reconstructed from scanned human data of the developing skeletal system of a six week old embryo. During this phase of development, the foreshadowing cartilaginous models of bone begin to ossify and terminal portions of the limb buds become flattened to form the hand plates and footplates, the future hands and feet. Growing outward from the middle of the shaft, the growth of the long bones that give the body its adult contours terminates between the ages of seventeen and twenty-one.