BALTIMORE -- Your first reaction on seeing Robert Colescott's paintings is to laugh out loud. Your second -- if you're white, and reasonably sensitized -- is to swallow your guffaws. If you choke upon your giggles, Colescott's got you where he wants you. Twenty-one of his big canvases are now on exhibition at the Baltimore Museum of Art. They stab as they embarrass. They amuse as they offend.

Half of Colescott's gags, his sendups of the masters, are socially acceptable. The other half are not.

His witty and affectionate pokings at Picasso are entirely permissible. Delacroix can take it, so can Manet and Matisse, and de Kooning is fair game. But Colescott's racial stereotypes -- his wide-eyed Aunt Jemimas, his cotton-haired Uncle Toms and pink-lipped, black-faced lechers -- are something else again.

I have no idea how blacks respond to Colescott's pictures. Do they smile? Do they cringe? The offensiveness of certain jokes depends on the comedian. Jews who laugh at JAP gags told by Jackie Mason, or blacks who roar with Richard Pryor, might glare to hear the same jokes told by Johnny Carson. Context is as crucial in Robert Colescott's art. There's a double standard working. The first glimpse of these pictures tells you Colescott's black. Had a white man made these paintings, they wouldn't be on view.

One big and jokey picture here from 1975 is called "George Washington Carver Crossing the Delaware: Page From an American History Textbook." It's based on Emanuel Leutze's patriotic chestnut, except the Father of Our Country is nowhere to be seen. Instead, the pinch-faced scientist is standing in the rowboat. And all its passengers are black. They do not look like warriors. One's just caught a catfish. One's a bootblack, one's a cook. The minstrel in the stern is strumming on a banjo. One is swigging from a jug.

Colescott, in the catalogue, explains that when he made the picture he was "talking about the way U.S. history was taught when I was growing up. There were two blacks mentioned as significant ... Carver and Booker T. Washington. Just two. By contrast, the menial workers -- Stepin Fetchits, Aunt Jemimas, bootblacks, etc. -- were all too well known to us and to everyone ... We were allowed only two heroes in all of U.S. history."

In "Natural Rhythm: Thank You Jan Van Ecyk" (1976), Colescott's re-envisioning of the "Arnolfini Wedding," the pregnant bride is black. In his "Eat Dem Taters" (1975), Colescott's version of van Gogh's "Potato Eaters," the peasants all are grinning broadly, and all of them are black. His "I Gets a Thrill Too When I Sees De Koo" (1978) is a saucy takeoff on de Kooning's famous "Woman I" of the early 1950s -- but here her face is Aunt Jemima's.

Such race-shifting is seen often in this show, nowhere more tellingly than in "Shirley Temple Black and Bill Robinson White" (1980). "I got my idea," the painter has explained, "from Shirley Temple Black. She was Shirley Temple and then she married and became Black. When she went to Ghana as ambassador for the United States, I felt something in my insides; I should have known that when a 'Black' went to Africa as ambassador, it would be Shirley Temple." With the skin colors reversed, old and stereotypical sexual innuendos rise from Colescott's painting, in which America's Sweetheart is a little black girl and Bojangles is white.

"I was born in 1925, and brought up in Oakland, California," the painter told the Baltimore Sun. "Dad and Mother came from New Orleans, and moved to Oakland after World War I. Dad was a waiter on the railroad. They were working-class people, but not common people. Most of my formative experiences were Depression experiences. Movies were the dominant art form, and I got my ideas of archetypes and stereotypes from filmmakers."

One is not surprised to learn that he grew up in Oakland. Some smell of that bland city, and of its nonbland artists, is apparent in his art.

His painting has about it some of that gross-'em-out vitality, that voodoo-comic voice, of Ishmael Reed's writing. Oakland may be dull, and San Francisco twee, but much Bay Area art -- think of Robert Arneson's ceramics, of William Wiley's paintings or those of Peter Saul, of R. Crumb's tough cartoons, of Roy De Forest's dogs, the music of the Grateful Dead and Lawrence Ferlinghetti's verse -- has, as Colescott's painting does, a happy coarseness at its core.

After getting his BA and MA at Berkeley, Colescott went to Paris where, in 1949 and 1950, he studied in the studio of Fernand Le'ger. Later he allied himself with David Park, the young Richard Diebenkorn, and other Bay Area figurative painters. His touring "retrospective" covers just 11 years, 1975 to 1986. It was relatively late that the painter found his odd, sardonic voice.

He told the Sun: "I'm not sure these paintings will make anybody a better person, or improve conditions, but I do them anyway -- anything you can do to remind people that they have the freedom to talk about anything ... "

Colescott's gags would seem just gags -- good ones, bad ones, take your pick -- if he weren't such a good painter. What he feels about his fellow blacks may be problematical -- consider the smug black collector surrounded by his treasures, his Barnett Newmans and Frank Stellas, his Dan Flavins and Roy Lichtensteins, in Colescott's "Tea for Two (The Collector)" of 1980. Is he making fun of collectors? Black collectors? Or of blue-chip artists? I don't know Colescott's politics. But his deep love of art history is not in doubt at all.

He loves Matisse and Manet. He loves Delacroix as well. His responses to Picasso's Africa-influenced "Les Demoiselles d'Avignon" (Colescott calls his paintings "Les Demoiselles d'Alabama") are more than juicy jokes: They're also heartfelt acts of homage. And Colescott's paintings have about them a patterned richness and a freedom, a kind of bold ebullience, that are unmistakable. His messages may make you squirm. His satires don't always work. But the man knows how to paint. His bright colors and his brushwork give real pleasure to the eye.

But it is not pleasure only, at least not pleasure unalloyed, that they deposit in the mind. Something stings within these pictures. They conjure an old question: How is the black artist now working in America supposed to deal with his blackness? Some, working in an abstract mode, seem, as surely is their right, to rather dodge the issue. Others, so intent on celebrating racial pride, make pictures that occasionally verge on propaganda. Colescott in his paintings announces both his blackness and his deep allegiance to the white world's art history. There is pride within his pictures, and not just pride, but pain.

His exhibition was organized by the San Jose Museum of Art. Its ill-designed catalogue contains useful essays by Lowery S. Sims and Mitchell D. Kahan. His show will travel to Portland, Ore., Akron, Ohio, Norman, Okla., Houston, Manhattan and Seattle after closing in Baltimore on Feb. 28.