Lindsay Lohan and her famous firecrotch were none too pleased to see professional pouty-lipped poseur Paris Hilton at Lady Gaga's fragrance launch party -- cough, circus, cough -- in New York City last Thursday, Sept. 13.

A witness said that LiLo "freaked out when she saw Paris," since neither knew that the other was on the guest list at the high-profile fete, whose organizers clearly had a D-list quota to fill.

In a sign of how the mighty have fallen, an insider said Hilton “marched in and tried to push her way through the crowd to Gaga,” but turned back when no one moved out her way because they either didn't know who she was or, more likely, didn't care. And that's when Lindsay caught sight of her.

The ladies were once besties -- which in Hollywood terms means "they've been photographed together" -- but fell out six years ago after bloated and sweaty oil heir Brandon Davis ranted about Linds and called her a "firecrotch" in front of the paparazzi while Hilton giggled demurely in the background.

So at Thursday's party, LiLo reportedly "stepped back with these big eyes" when she nearly crossed paths with The Hilt, shaking her head and repeating, "No, no, I can’t."

And then, crisis averted, she eventually pulled herself together enough to mingle amongst the revelers, allowing the world to spin peacefully on its axis once more.

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