From The Secret Lives of Waldo Kitty:
Waldo (Howard Morris) imagines himself as Captain Hurk of the Starship Second Prize, being pursued by Tyronius (Allan Melvin). Coincidentally, Waldo Kitty replaced Filmation's adaptation of Star Trek on the NBC schedule. Here's "Cat Trek":
Capt. Hurk would return in "Ping or Pongo".
As it happens, Filmation got in trouble with the estate of Walter Mitty author James Thurber, as his widow alleged that the studio had used the basic title without permission. For this reason, the series was rechristened as The New Adventures of Waldo Kitty when it was reissued as part of Groovie Goolies & Friends a couple of years later.