Very nice @H8_modern !! I bid on an example recently, but someone else wanted it even more The example Zumbly posted is simply wonderful.
I can't remember the name of of it, but I saw a show that suggested inspiration for Ketos was of fossilized skull (and others fossils being displayed and heroes bones). The book on the subject is " The first fossil Hunters"
Can it be classified as an " Extinct Animal " ? Could zoologists specify the size and weight of such prehistoric animals? That's just out of curiosity.