Figure 3

Overview photographs of Nothosaurus humeri thin sections in normal light. A-D and F-G, diaphyseal sections; E, metaphyseal thin section. In all images, ventral is at the bottom. A, N. marchicus/N. winterswijkensis humerus (MfN R 174–2); B, N. mirabilis humerus (SIPB R 54/2); C-E, N. giganteus humeri (C, SIPB R 53, D, SIPB R 45, E, MHI 1903, Section 1); F-G, Nothosaurus. sp. indet. humeri (F, MHI 1906, G, MHI 633). Note the triangular cross sections of the Nothosaurus humeri (A-D, F-G). Humeri in A and F are osteosclerotic (they have a low MI and the medullary regions are mostly infilled by endosteal bone and calcified cartilage), unlike the humeri in B, C and D which show thinner cortices and large medullary regions. The juvenile humerus in G has a small medullary cavity but highly vascularized cortical bone.