Fig. 2 in Growth and life habits of the Triassic cynodont Trirachodon, inferred from bone histology

Fig. 2. Transverse sections of Trirachodon femora. A. Femur (NMQ− R3282a), estimated to be 51% adult size; A1, highly vascularized fibrolamellar bone, scale bar 250 µm; A2, high magnification of the same, showing two indistinct annuli (arrowheads), scale bar 125 µm. B. Femur (SAM−PK−5881a) consisting of moderately vascularized fibro−lamellar bone with a parallel−fibred region at the periphery (arrowhead). The vascular canals are radially and longitudinally orientated, with some anastomoses. Arrow indicates a secondary osteon, scale bar 250 µm. MC indicates medullary cavity.