(Mental Floss) -- 1942 -- Tweety forced to wear clothes

Lucille Ball's character was pregnant, but was never allowed to say the word "pregnant."

Tweety Bird first appears in "A Tale of Two Kitties." Animator Bob Clampett originally draws him without feathers, but the Hays Office censorship bureau thinks the plucked bird is just a little too naked. So Clampett covers Tweety's titillating flesh with yellow plumage.

Clampett doesn't let this pass quietly, though. In the episode, a cat yells to his partner, "Give me the bird!" To which the other cat responds, "If the Hays Office would only let me, I'd give him the bird, all right!"

1952 -- Lucy gets knocked up

Ball's pregnancy during an entire season of "I Love Lucy," the actual word "pregnant" isn't allowed on air. Instead, the show uses phrases that seem equally informative but (somehow) less fraught with sin, such as "with child," "having a baby," and "expecting."

1956 -- Elvis' pelvis shoved off screen

Elvis' first appearance on "The Ed Sullivan Show" is seen by 60 million people (about 80 percent of America's TV owners at the time). His hips, however, aren't so lucky. After his cover of Little Richard's "Ready Teddy" -- complete with trademark gyrations -- the camera switches to a close-up of his face as not to over-stimulate the American public. By the time he appears on the show for the third time (in January 1957), he's only shown from the waist up.

1959 -- Advertisers rewrite history

On the dramatic anthology series "Playhouse 90," an episode titled "Judgment at Nuremberg" has all references to gas chambers eliminated from its re-enactment of the Nazi trials. This is done at the behest of the show's slightly sensitive sponsor, the American Gas Association.

1964-1966 -- Censors throw down in navel wars

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Mary Ann from "Gilligan's Island," Jeannie from "I Dream of Jeannie," and "Gidget" are all barred from baring their navels. Actress Mariette Hartley receives the same treatment in a 1966 episode of "Star Trek," but the show's director, Gene Roddenberry, gets his revenge in 1973. He recasts Ms. Hartley in the pilot for his new show, "Genesis II," and gives her two belly buttons.

1967 -- Actors successfully hide pot on set

It's a tough year for network censors struggling to keep up with the hippie culture's profusion of drug slang. Ed Sullivan requests that The Doors change the lyric "Girl, we couldn't get much higher," since it sounds suspiciously like a drug reference. Meanwhile, "The Smothers Brothers Comedy Hour" has a recurring skit about Goldie, a housewife with her own talk show called "Share a little tea with Goldie." The skit constantly plays on the tea/marijuana connection, which goes straight over the censors' heads. Goldie's opening lines include "Hi[gh]! ... And glad of it!"

1970 -- Studios learn to cope with cannibalism

"Monty Python's Flying Circus" airs "The Undertaker Sketch," in which an undertaker convinces a man that the best way to dispose of his deceased mother is to eat her (with French fries, broccoli, and horseradish sauce). Bizarrely, the BBC allows this to be shown, but only if the sketch ends with the studio audience storming the stage in disgust.

1979 -- Miss Piggy's ultimate rejection

"The Muppet Show" is banned from TV in Saudi Arabia, due to Miss Piggy's, well, pig-ness. (The Prophet Muhammad declared the flesh of swine "an abomination.") Merchandise bearing her likeness is confiscated from shops and destroyed.

2004 -- Nipples by the number

We know it's a little obvious to mention Janet Jackson's "wardrobe malfunction" during Super Bowl XXXVIII, but it's worth recapping a few stats:

• Amount of time the nipple spent on-air: 1.01 seconds (we actually timed it)

• FCC fines levied on CBS: $550,000

• Cost to NFL (in sponsor refunds): $10 million

• Ranking among 2004 Internet searches: 1

• Ranking in TiVo's "most rewound moments": 1

• Number of American complaints to network: more than 500,000

• Number of Canadian complaints: about 50

2006 -- South Park draws up controversy

Comedy Central prevents "South Park" from using the image of the Prophet Muhammad in the episode "Cartoon Wars." However, for the benefit of freeze-frame geeks everywhere, Trey Parker and Matt Stone sneak a tiny Muhammad into the opening credits in a shot that shows every resident of the town.

The turbulent life of the TV toilet

•1957: Before it airs, CBS yanks the pilot episode of "Leave It To Beaver" because of its plot: Wally and the Beav mail-order a baby alligator and are forced to hide it in the tank of the family's toilet. CBS finally decides the show can air, but only if all shots of the toilet seat are excised. The toilet tank is left unharmed, marking the first time a toilet (or half of one, anyway) appears on TV.

•1960: Host Jack Paar walks off the set of "The Tonight Show" in the middle of taping an episode. He would not return for a month. The reason? Censors cut a joke that used the phrase "water closet."

•1971: A major breakthrough occurs as the toilet is finally allowed to perform its function. The first flush is heard, but not seen, on a first-season episode of "All in the Family." TV's first flusher is, of course, Archie Bunker.

•1973: Jack Paar's censors are proven right about the toilet's power over "The Tonight Show" audience. In the era of gasoline shortages, Johnny Carson jokes about an imminent shortage of toilet paper. Across the country, panicked viewers go on a hoarding spree, emptying store shelves and forcing Carson to publicly apologize the next night. E-mail to a friend

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