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
Femur the bone. Some species of whales, snakes, and other non-walking vertebrates have vestigial femurs. One of the earliest known vertebrates to have a femur is the "eusthenopteron", a prehistoric lobe-finned fish from the Late Devonian period. Structures analogous to the third trochanter are present in mammals, including some primates. In invertebrate zoology the name "femur" appears in arthropodology. The usage is not homologous with that of vertebrate anatomy; the term "femur" simply has been adopted by analogy and refers, where applicable, to the most proximal of (usually) the two longest jointed segments of the legs of the arthropoda. The two