Matthew Carl Ashley, dressed in a sparkling white Navy uniform, clutched his diploma and let go with a wild, ungentlemanly shriek.

Bartley Marvin Dibble, also in uniform, accepted his graduation document and soared into the air with arms and legs extended in four directions.

And, diploma in hand, Richard Scott Barbon flipped -- literally -- across the blue carpeted stage, right in front of Adm. William J. Crowe Jr., chairman of the Joint Chiefs of Staff, and other officials assembled here for commencement ceremonies today for 1,015 graduates of the U.S. Naval Academy.

Some members of the Class of '86 were more subdued.

Jeffrey Michael Bellistri, a star lacrosse player who was expelled from the academy in March for allegedly using cocaine and then reinstated in April by Navy Secretary John F. Lehman Jr., walked quietly to the podium to accept his leather-bound diploma of navy blue marked with a gold academy seal. After the ceremony at Navy-Marine Corps Memorial Stadium, Bellistri declined to answer any questions and ran from reporters.

But before departing, Bellistri joined his classmates in the celebrated "hat toss," a tradition at the academy that dates to 1912.

After throwing their white hats into the air to mark the end of the graduation program at Annapolis, the newly commissioned officers yelled, hugged each other, grinned, posed for family snapshots and generally unloaded all the emotion that had been building during their four years at the academy.

"It's a lot of pressure . . . . It's a relief to be done," said Jeffrey David Semancik, a physics major who was the academy's top graduate this year.

The 21-year-old ensign, who joined his family for a picnic lunch after the commencement, grew up in New Hampshire; his family moved to Herndon, Va., a year ago. Semancik's father George, a former Navy enlisted man, works for a Fairfax defense contractor.

This year's graduating class of 64 women and 951 men was advised by Crowe, the commencement speaker, to try to "absorb . . . wisdom" from senior officers, keep "an open and questioning mind," and maintain a sense of humor.

Crowe, who graduated from the academy 40 years ago, cautioned that "at times the path ahead of you will be difficult, boring, discouraging and certainly not well marked."

But as graduates of the Naval Academy, he said, "you enjoy an advantage you must never overlook . . . . You are part of a long and deep tradition that you can call on in times of strife and peril. You are steeped in the history and the standards of the world's foremost Navy and Marine Corps team . . . . "

In closing, Crowe told the graduates they will be involved in shaping U.S. foreign and military policy and urged them to remember what President Lincoln, in the Civil War, told his generals: "When you are in the field, you are the Republic."

"That," Crowe said, "is no less true for the Class of 1986 -- you are the Republic."