The Ichthyosaurus models are based on Triassic or Jurassic fossils from Europe. Though the three ichthyosaurs are partly in water, they are implausibly shown basking on land like seals. Owen supposed they resembled crocodiles or plesiosaurs. Better fossil evidence shows that they have more in common with sharks and dolphins, having a dorsal fin and fish-like tail, whereas in Hawkins's models the tail is a flat protuberance from a straight backbone. A further discrepancy is that the models' eyes have exposed bony sclerotic plates, Owen conjecturing that with such large eyes they had "great powers of vision, especially in the dusk".McCarthy, 1994. p. 55 They became one of the three mascots of Crystal Palace Park, along with the Iguanodon and Megalosaurus (although ichthyosaurs are not dinosaurs). Coincidentally, the models more closely resemble more basic ichthyosaurs such as Cymbospondylus.McCarthy, 1994. pp. 54–55
