Fig. 3 in Growth and life habits of the Triassic cynodont Trirachodon, inferred from bone histology

Fig. 3. Transverse sections of Trirachodon tibiae. A. Tibia (NMQR3282b) showing a highly vascularized reticular network in fibro−lamellar bone. Two annuli are noted in the mid−cortex and periphery respectively (arrowheads). B. Tibia (SAM−PK−K5881c) where annuli are observed interrupt− ing the fibro−lamellar bone tissue at intervals (arrowheads). A LAG (open arrow) is observed at the periphery and secondary osteons (closed arrow) are seen scattered throughout the cortex, sometimes reaching the subperiosteal surface. Large resorption cavities are also noted. MC refers to medullary cavity. Scale bars 125 µm.