Ichthyosaurus and Plesiosaurus skeletons

Skeleton of Ichthyosaurus communis (fish lizard) and Plesiosaurus dolichodeirus. Fossils of extinct Jurassic era dinosaurs. Copperplate stipple engraving from Jussieu's 'Dictionnaire des Sciences Naturelles' 1816-1830. The volumes on fish and reptiles were edited by Hippolyte Cloquet, natural historian and doctor of medicine. Illustration by J.G. Pretre, engraved by Plee, directed by Turpin, and published by F. G. Levrault. Jean Gabriel Pretre (1780-1845) was painter of natural history at Empress Josephine's zoo and later became artist to the Museum of Natural History. (Photo by: Florilegius/Universal Images Group via Getty Images)