Fig. 7

Bone histology of central shaft area of ceratohyal of Saurichthys sp. (PIMUZ T 2138). Image a in normal transmitted, b in cross-polarized, and c in cross-polarized light using lambda compensator. The inset in a shows the area where Howship’s lacunae were identified. Note that specimen has been slightly crushed and, therefore, the outline of the bone and its medullary cavity would have been more oval. Fourteen growth marks (as indicated by black and white arrow heads) are well visible in the section. The medullary cavity was at least partly lined with endosteal lamellar bone and comprised few internal trabeculae. HL Howship’s lacuna, LB lamellar bone, PFB parallel-fibered bone, ShF Sharpey’s fibers