Emma Watson strips down for 'Natural Beauty' book (Photo, poll)

Emma Watson is showing some skin -- for a cause, of course.

The 22-year-old actress, who is perhaps best known for her role as Hermoine Granger in the "Harry Potter" series, shed her clothing for a series of photos for James Houston's new book, "Natural Beauty."

Some of the photos show the English actress baring her shoulders and debuting a fresh-faced look (see photo above), while others show her in minimal m! akeup suggestively posing with orchids.

"My friend is supporting GlobalGreenUSA with his book Natural Beauty. It's out now. : ) X," she Tweeted, with a corresponding photo from the shoot.

The book of portraits will be released in late spring of 2013, and will follow with an exhibition in New York City in April. The book is set to include a number of celebrities, including Christy Turlington, Adrian Grenier, Brooke Shields, Arizona Muse, and Elle Macpherson, among others.

The book and event series benefit Global Green USA, whose mission is to "foster a global value shift toward a sustainable and secure future," according to their website. The group works on advocating "smart solutions to global warming including green building for affordable housing, schools, cities and communities that save money, improve health and create green jobs."

The project's webisode is set to be launched on March 25, and the book can be pre-ordered on Amazon's website.

Earlier this week, rumors that the starlet was picked to play the role of Anastasia "Ana" Steele in the upcoming film adaptation of the hit book "Fifty Shades of Grey" were shot down.

The book's author, E.L. James, dismissed the casting rumors on her official Twitter account on Friday, March 15, post! ing: "The! re have been no casting decisions made about 'Fifty Shades.'"

The starlet took to her own Twitter account to dismiss the claims, posting: "Who here actually thinks I would do 50 Shades of Grey as a movie? Like really. For real. In real life."

The actress might just further shed her good girl "Harry Potter" image with a role in the upcoming film "The Bling Ring." The movie is based on the true story of a group of celebrity-obsessed teens who broke into the homes of several stars such as Lindsay Lohan and Paris Hilton.

Watson plays a burglar named Nicki, which is not the name of any of the real-life suspects, but is allegedly based on one of the burglars. The film was directed by Sofia Coppola and is due out on June 14.

What do you think of Watson's "Natural Beauty" photo? Vote in our poll below! Also, check out the video campaign for the photography book.

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