Primus will appear with Tool drummer Danny Carey during scheduled September dates as Tim "Herb" Alexander recovers from recent open-heart surgery.

Primus frontman Les Claypool continued to heap praise on Alexander, even in his absence, calling him a "polyrhythmic Viking of extreme and unique talent" in a new talk with Rolling Stone. He adds, however, that Carey is the perfect temporary replacement. "Whereas Herb is the stocky, Easter Island-faced, boulder of a drumming human, at nearer to seven feet," Claypool says, "Danny Carey is the mighty redwood tree of percussion; towering over his kit like a golden-haired noble spruce."

Alexander, a founding member of Primus who'd previously served stints from 1988-96 and again from 2003-09, suffered a heart attack last month -- and needed immediate triple-bypass surgery. He has earlier played with Tool singer Maynard James Keenan's other bands A Perfect Circle and Puscifer.

Carey will be with Primus for Riot Fest appearances in Chicago and Denver, and will also play the after-party show at Chicago's Concord Music Hall in September. "We are extremely excited to have him aboard," Claypool says, "and I would wager we are equally if not more intrigued than most by what kind of sounds are going to come out of the three of us once we actually get in a room together and do more than just consume fancy booze."

Claypool says they went ahead with the shows in order to help Alexander financially through this health issue. The drummer is expected to return in time for shows in October, as Primus issues its first album with Alexander in nearly 20 years. 'Primus and the Chocolate Factory with the Fungi Ensemble' is due on October 21.

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