Yes, it is easy to see how their imaginations could piece together pieces of existing animals for bones that resembled those of modern animals
...and if there were no professionals examining these thoroughly, the descriptions could easily be passed along by word of mouth and embellished...and the gigantic un-assembled bones could act as convincing evidence for creatures of any shape
Being able to unify these creatures of our predecessors with our dinosaurs gives me a heartening feeling
In the early days of modern archeology they have made mistakes also, if anyone comes across any of these modern mistakes please post a link to it here.