Fig. 8

Histological sections of the embryonic skeletons. a1, cross section of the tibia of IVPP V20182, showing fibrolamellar bone with relatively large and rounded vascular canals and poorly defined marrow cavity; scale bar = 1 mm; a2, the same cross section in a1 with the vascular canals highlighted in green; scale bar = 1.2 mm; b1, cross section of the tibia of IVPP V20183, showing fibrolamellar bone with compacted, longitudinal and concentrically arranged vascular canals, and a well defined marrow cavity; scale bar = 1.2 mm; b2, the same cross section in b1 with the vascular canals highlighted in green; scale bar = 1.2 mm; Abbreviations: MC, marrow cavity