ONTOGENIC CHANGES IN THE BONE-HISTOLOGY OF THE LATE JURASSIC ORNITHOPOD DRYOSAURUS-LETTOWVORBECKI

Histological changes through ontogeny in Dryosaurus lettowvorbecki are reported. Thin sections of femora are examined using light microscopy (ordinary and polarized light). The results suggests that Dryosaurus grew rapidly throughout ontogeny without any pauses in its bone deposi tion rate. This pattern differs uniquely from the histological descrip tions of prior studies of growth series of other dinosaur taxa. This s tudy provides support to the hypothesis that dinosaurs probably exhibi ted a range of physiologies and growth patterns.