I Forgot:
Grindl, with Imogene Coca
The Bill Dana Show
The Colgate Comedy Hour, particularly the shows hosted by Dean Martin and Jerry Lewis
The Hathaways, with Peggy Cass and the Marquis Chimps
Ozzie and Harriet (Because of the Nelsons' fearsomely wholesome image, most people don't remember that they hold a little-known distinction; they were the first sitcom couple to share a double bed, two decades before any others did)
The Ann Sothern Show, plus its other iteration, Oh, Susannah!
My Little Margie, with Gale Storm (whose '50s recordings for Dot Records are not nearly as well-remembered as they should be)
The Ernie Kovacs Show, with the great Nairobi Trio performing (more or less) "Solfeggio"
That Was the Week That Was, a brilliant, short-lived political satire show often referred to simply as TW3
and while it wasn't strictly a comedy, it did have lots of clowns:
International Showtime, a summer replacement series showing circuses from all over Europe. Don Ameche was ringmaster each week, and Studebaker was the sponsor. To this day, I can't hear Alfven's "Swedish Rhapsody" on my local classical station without thinking of this show - it was used as the theme music.