Fergie is showing off her lovely lady lumps.

The sexy Black Eyed Peas singer spent the holiday weekend in Cancun, where she proudly posed in a striped bikini in a photo she posted on Facebook.

She looks amazing ... but, unfortunately, the 37-year-old's sexy husband Josh Duhamel didn't follow suit and share a shirtless pic too. Maybe next time!

See what other stars did for Memorial Day here -- and check out more hot shots of Fergie Ferg in the gallery above!

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