Fig. 5 in Bone histology of Protoceratops andrewsi from the Late Cretaceous of Mongolia and its biological implications

Fig. 5. Bone microstructure of the parietal frill in adult Protoceratops andrewsi Granger and Gregory, 1923, Bayn Dzak, Mongolia, Late Cretaceous (ZPAL MgD-II/33). A. Sagittal section. B, C. Transversal sections; note the condensations of the fossilized collagen fibers strengthening the porous tissue (B) and the formation of the small erosion lacunae at the external surface of the frill (C). A, B1, C, normal light; B2, B3, polarized light.