Jimmy Buffett is the singer laureate of beach bums. His songs extol the virtues of ocean, tequila and marijuana. What saves him from terminal mellowness is his ability to laugh at himself. Last night at the Merriweather Post Pavilion, Buffett's humor was clicking better than it ever has on record and he made the lounge lizard's life sound lovely.

Buffett's walrus mustache made him look like a bemused Mark Twain as he tossed off hilarious stories between songs. His comedic talent was clearest on his many embellishments to Lord Buckley's old talking blues, "God's Own Drunk." But most of his songs sparkle with the humor of absurdity, ranging from "Cheesburger in Paradise," about junk food, to "Fins," about beach bar sharks.

But a number of Buffett's songs looked at the underside of the vagabond's life. Missed opportunities and fading possibilities showed up in songs like "Margueritaville," "A Pirate Looks at Forty" and "Sending the Old Man Away." The last was one of several songs previewed from a new album due out next week. One of them was an enchanting lullaby with counterpointed choruses, "Song for the Children, Song for the World."

The opening act, John Stewart, has been rescued from the limited following of cultdom by "Gold," a hit single made with Fleetwood Mac's Lindsey Buckingham and Stevie Nicks. Buckingham and Nicks' lush harmonies were defintely missed last night, for Stewart is a limited singer and his band has little range. But his lyrics were more substantial than a Fleetwood snack. On songs like "Fire in the Wind" and "Midnight Wind" Stewart's Roger McGuinn-like 12-string guitar and traditional roots made for folk-rock reminscent of the old Byrds.