FIG. 3. — A, Scapula of Mylodon Owen, 1859 (section no. 53),cross section in ordinary transmitted light, the bone tissue is of the dense Haversian type;B, Mylodon osteoderm (section no. 67), main frame: radial section in ordinary transmitted light; detail: polarized transmitted light revealing cyclic growth marks in the outer cortex; C, Typotherium Gervais, 1867, a junior synonym of Mesotherium Serres, 1867 molar (section no. 75) at low enlargement, at the crown-root junction, three different tissues can be observed in ordinary transmitted light: orthodentine (d), cement (c), and wedged between the two formers, a triangular splinter of enamel (e); D, closer view at the striae of Retzius (Str. r) in the enamel of Typotherium molar, same section as above, transmitted polarized light; E, cetacean rib (section no. 82), cross section in ordinary transmitted light, bone tissue is of a dense Haversian type (hb); F, Macrotherium Lartet, 1837, a synonym of Anisodon Lartet, 1851 ulna (section no. 89), cross section in ordinary transmitted light. Dense Haversian tissue (hb). Scale bars: A, 1.15 mm; B main, 2.10 mm; B inset, 2 mm; C, D, 1 mm; E, 0.30 mm; F, 0.40 mm.