(FORTUNE Magazine) – ''Have a Barbara Bush leg,'' pressed my Moscow dinner party hostess, whose husband is a comfortably-off construction worker. It turned out to be a regular baked chicken leg, though noticeably meatier than the scraggy variety more common in the Soviet Union. My hostess explained the nomenclature: ''They're so fat. George Bush's legs are too thin. Only Barbara Bush would have legs as fat as this.'' A sort of tribute to American prosperity, one supposes, but clearly the woman hasn't studied pictures of the First Lady, who has what used to be called a well-turned ankle. As it turns out ''Barbara Bush legs'' is a common Muscovite phrase for U.S. chicken thighs and drumsticks that sell for about $1.55 a pound at the official rate, roughly the same as their Soviet equivalents. Russians believe that the chicken legs are part of U.S. aid. Not so. The Soviet government pays U.S. producers hard currency for the poultry. In the 16 months since the buying began, the country has imported some 500 million pounds, about 13% of the total U.S. kill. So far no reaction from Mrs. Bush. But a spokesperson says, ''Bon appetit.''