Lizard (Spider-Man (1967))

Dr. Curtis Conner, aka The Lizard, lives in the Florida Everglades, devoting his life to reptilians and swamps. That would later catch up with him....

In Where Crawls The Lizard
Conner made his first appearance in this episode. He was said to be a doctor who was researching swamp fever. His explorations resulted in him accidentally turning himself into the fearsome Lizard. He fought Spider-Man in Florida, until he was cured by Spidey and sent back into the care of his family.

In Conner's Reptiles
A year has passed since the last "Lizard" encounter, when Conner chose to disgard the research on swamp fever, and fixate his attention on giving high intelligence to reptiles, and so his creation, Reptilla (not to be confused with the woman of the same name from Marvel Comics), captured Conner. Spider-Man freed him, and he chose to alter his research completely, so no more Lizard problems...

Trivia

 * Dr. "Conner" is named in the comics and films Conners, but this, along with a few other adaptations, take away the "s" at the end of the name. (Though, it should be noted that Spider-Man addressed the Doctor as "Conners" at the end of Conner's Reptiles).
 * The Lizard was called "Lizard-Man" throughout his debut episode, but the episode's title addressed him by his comic book name.
 * J. Jonah Jameson heard at the end of the first Lizard episode that a film was shooting in the Everglades, and convinced himself that the Lizard-Man was never real, and just part of the movie; but in the second Lizard episode, one year later, Jameson completely recalls that Conner had been The Lizard-Man, with no mention of the movie being filmed there.