In Jurassic Park (both the novel and the film) feature a scene where Nedry is killed off while trying to escape the island by a venom-spitting Dilophosaurus (code-named "Spitter" in the film's marketing). Although the Dilophosaurus was considerably taller (Although the one in the film might've not have been an adult) and didn't have any venom/frills in 'real life' (Something that's been used in several non-Universal licensed Dino toys, sadly), I've always wondered why it never appeared in TLW or Jurassic Park III. I suppose because the sequels wanted to focus on newer Dinosaurs (Spinosaurus, Compsonathus) or related prehistoric animals (Pterandon), or mainly just the big bads from the first film, T-rex and Velociraptors. Another reason of course could be the element of surprise was gone-in the film at least the Dilophosaur initially appears to be benign , only for it to reveal it's true 'colors'. The compsonathus kind of fulfilled that role in TLW. I also felt the Triceratops could've done more in all the films apart from be sick and have a cameo ramming into Ludow's tent-and reportedly a deleted scene would've focused more on them-and a T-rex/Triceratops battle would've been fantastic. Oh well, maybe in the new film that Spielberg is reportedly getting ready.