Scelidosaurus partially sea-dwelling. Owen had not indicated a holotype. In 1888, Richard Lydekker while cataloguing the BMNH fossils, designated some of the hindlimb fragments described in 1861, specimen BMNH 39496 consisting of a lower part of a femur and an upper part of the tibia and fibula, together forming a knee joint, as the type specimen, hereby implicitly choosing them as the lectotype of "Scelidosaurus". Lydekker gave no reason for this choice; perhaps he was motivated by their larger size. Unfortunately, mixed in with the "Scelidosaurus" fossils had been the partial remains of a theropod dinosaur and the femur and tibia
Tibia malleolus. The lower extremity of the tibia together with the fibula and talus forms the ankle joint. The inferior articular surface is quadrilateral, and smooth for articulation with the talus. It is concave from before backward, broader in front than behind, and traversed from before backward by a slight elevation, separating two depressions. It is continuous with that on the medial malleolus. The anterior surface of the lower extremity is smooth and rounded above, and covered by the tendons of the Extensor muscles; its lower margin presents a rough transverse depression for the attachment of the articular capsule of the