Skull and Bones, the oldest and most secret senior society at Yale University, boasts many distinguished alumni but none more prominent today than a ``spook'' from the class of 1948 _ George Herbert Walker Bush. Little is known about the strange rituals and practices of the 156-year-old society, and that's the way its members want it. The rites are rumored to include placing initiates in a coffin and requiring them to plunge naked into a pile of mud. Some of the rumors come from rival societies, and may be suspect. No one but members really know what goes on inside the windowless, mausoleum-style structure of brown sandstone to which Bonesmen retreat. But as the Republican presidential nominee's own experience has shown, membership in the society forms powerful bonds of friendship that endure long after graduation. The vice president was one of 15 Yale juniors tapped for Skull and Bones in 1947. To this day, the Bonesmen who once heard him recount some of the innermost secrets of his life remain his good friends. Perhaps because of the pledge of secrecy that Bonesmen take, Bush did not mention his Skull and Bones membership in his autobiography, ``Looking Forward.'' The society has long been suspected of ritualistic thefts. A group of history buffs in El Paso, Texas, claimed that the skull referred to in the society's name belongs to Mexican revolutionary Pancho Villa, whose grave was robbed in 1926. Endicott Davison, a lawyer who says he speaks for Skull and Bones, said the society does not have the skull. The former chairman of the San Carlos Apache tribe in Arizona charged recently that Bush's father, Prescott Bush, stole the skull of Apache chief Geronimo years ago, and that it is still on display at Skull and Bones' inner sanctum. That claim was denied by the vice president's brother, Jonathan Bush. One thing is not disputed: Bush the Bonesman is in powerful company. Brothers of the order have included Henry Stimson, Averell Harriman, Henry Luce, Potter Stewart, McGeorge Bundy, Archibald MacLeish, William F. Buckley Jr. and William Sloan Coffin Jr. Prescott Bush, a Republican senator from Connecticut, was a member. So was Bush's oldest son, George W. Bush, and about a half-dozen other family members. Skull and Bones is arguably the most famous and influential secret society in the United States, having served as a model for others that followed at Yale and other institutions. It was founded by William Russell, a member of the Yale Class of 1833, apparently in reaction to the stripping of secrecy from Phi Beta Kappa, the honorary scholastic society, during the rise of a national anti-secrecy movement. Skull and Bones is a private organization incorporated as the Russell Trust Association. It pays taxes to the city of New Haven and owns Deer Island, a resort on the St. Lawrence River. Giving Skull and Bones the benefit of the doubt, Brooks Mather Kelly, in a 1974 history of Yale, wrote of the society: ``Its purpose and programs were not revealed when it was founded and have never since been known. But that like most Yale societies it pretends to some intellectual and educational purpose can probably be assumed.'' The society ``comes from a tradition of elitism of which Yale was at the center,'' said Dan A. Oren, author of ``Joining The Club,'' a book published in 1985 about the relationship between the university and Jews. Skull and Bones became the first of the secret societies to admit a Jew in 1937. During the 1960s, the society tapped a number of outspoken radicals. Even today, however, it remains steadfastly all-male. Of Yale's seven secret undergraduate societies, only one other _ Wolf's Head _ refuses to admit women. Having women as members would interfere with one of the ways Bonesmen become true brothers. By all accounts, Skull and Bones initiates must lay bare their souls, telling their sexual histories and life stories in graphic detail. ``The danger of secret societies and entering into the club world is it allows members to lose sight of the common folk who aren't part of the elite,'' Oren said. But he said that Bush's experiences in World War II combat worked the other way. ``For so many veterans, their fight was against the racists and the bigoted values of Nazi Germany, so when they came back, they were embued with a strong sense of egalitarianism,'' Oren said. Bush, 21 and already married, entered Yale in 1945 after his discharge from the Navy, which awarded him the Distinguished Flying Cross and three Air Medals for his wartime exploits. While on one combat mission, Bush's plane was shot down and he was rescued by a submarine. Two fellow crewmen perished. Bush recounted his brush with death for Bonesmen in 1947 with great emotion, says former Rep. Thomas W.L. Ashley, D-Ohio, another member of the Bones class of 1948. ``What comes to mind was, he was an awful young guy who had had an idyllic kind of childhood who suddenly found himself in an airplane that was on fire facing a lot of death around him and almost certain death himself,'' Ashley said. Ashley and other Bonesmen in his Yale class are still close friends of Bush. ``Obviously, we became fond of each other,'' Ashley said. ``This was something kind of special to us.'' He added: ``George Bush is exactly just as loyal to other friends as those who happened to be in the society with him. His friendship across the social range is known to everyone.'' Members of the Bones class of 1948 came to Washington in 1981 for a reunion that included dinner at the vice president's mansion and a tour of the White House Oval Office. ``His having been a member of Skull and Bones and his continued involvement as an alumnus means he would probably be likely to draw upon past connections for the White House,'' Oren said. ``But his choice of people _ James Baker III to be campaign manager, Dan Quayle as vice president _ shows he's willing to go beyond Yale,'' Oren said. ``He has always maintained close connections to Skull and Bones, but his world certainly goes beyond New Haven.''