Top-Notch Series
I encountered this show in 1974 when I was 4 years old, and it was quickly cancelled after my first viewings. Nevertheless, though I never saw it again, it kindled in me a love of dinosaurs that has run through my entire life. (Remember: this was long before Jurassic Park or any other dino-related material in popular culture.)
Watching it again, I find it to be a high-quality series indeed. The idea of including science lessons was truly inspired. The father character is the sort of traditional, masculine-yet-intelligent WASP alpha male whose like would never be permitted on TV today -- more's the pity, for, as the program indicates, it was his kind who built the civilization that we have.
Just think: there was a time, just a single generation ago, when most European-American children in the U.S. had fathers like that.
I'm also struck by the quality of the animation -- so much superior to the Filmation shows with which I grew up (though I have a special place in my heart for those too). The skies have a unique tint that immediately establishes this valley as a different world.
I wonder which was the greater influence on this series: Burroughs's The Land That Time Forgot (the title of which is even referenced in the opening narration), or Conan Doyle, who penned the original Lost World novel.