Fig. 4

The reconstruction of growth of neoplastic tissue on the vertebral intercentrum ZPAL Ab III/2467 during ontogeny. A the normal, ontogenetically juvenile intercentrum, with only thin layer of the periosteal bone on the ventral part of the bone and visible nutrition foramina, nf reaching deep into the endochondral bone; B the overgrowth of the neoplasm producing osteoid, os, the normal periosteal and neoplasm are deposited at the same time; C during the growth the faster growing neoplasm gradually limit the space for normal bone. Finally, the neoplasm overgrowth the entire intercentrum. Art work by Jakub Zalewski