The thread of memory is beginning to fray. Destiny Morris can't recall her age. Is she 15 or 16? She is 16, her grandmother gently reminds her.

Where did she get the scars on her stomach? Destiny's mother explains they came from feeding tubes that helped keep her alive for several months. Why did the rock hit her here on the top of her head, rather than there, a little further back? Her mother shakes her head gently; she doesn't know.

Then, with no prompting, Destiny, suddenly alert, blurts out the names of the men who prosecutors said hurt her -- John, Maurice and Donnell -- names that she read in a newspaper some time ago.

Destiny Lynn Morris was the most seriously injured of 30 people who were hurt during an early morning incident on the Capital Beltway near Oxon Hill on May 27 when someone began hurling 5- to 15-pound landscaping stones at passing motorists.

Today, three men, John Lavon Burgess, Maurice Edward Ford and Donnell Richard Petite, all 18, will go on trial in Upper Marlboro. They face nearly 100 charges, including seven counts of assault with intent to murder. If convicted of those assault charges, each of the three would face up to 30 years in prison.

According to police, the suspects were identified during interviews of neighbors in the days after the attack. According to court documents, Ford identified the other two suspects and said the three threw the rocks after getting drunk while celebrating his high school graduation.

Several of the motorists suffered arm and jaw fractures, concussions, black eyes, cuts and bruises.

Destiny, who was not expected to live after a stone crashed through the window of the pickup truck she was riding in and struck her, lapsed into a coma for six weeks.

The rock caved in part of Destiny's skull, but through intensive physical therapy at a Wilmington, Del., rehabilitation hospital she has recovered her speech and eyesight and can walk in halting steps with a walker. "They hit me in the head with a rock. Now I am in a hospital," Destiny said in a rush of words.

Prince George's County Assistant State's Attorney John Smathers, who visited Destiny at her Hagerstown, Md., home Saturday to prepare her for the trial, said he may put the teenager on the witness stand as early as tomorrow. As they rehearsed, Smathers's questions focused on abilities that Destiny has lost because of her injuries.

"There is a part of me as a mother that says I don't want her there" in court, said Destiny's mother, Linda J. Cline, 35. "There is another part of me that says I want them to see what they did to her."

How much Destiny will be able to say is unclear. The girl was asleep, her forehead resting against her arms on the dashboard of the pickup truck while returning home with friends from an end-of-school trip to Ocean City, Md.

Suddenly three rocks rained down on the truck, one smashing through the window, striking Destiny on the top of her head. She was rushed to a hospital in Clinton, where doctors hoped she would live until her mother reached her bedside.

But she was out of the coma in six weeks, then smiling, then mouthing her mother's name, then talking and doing math, eating her favorite meal -- a McDonald's hamburger and fries -- and calling home several times a day.

"I wouldn't have given two cents" for her chances of living, said Destiny's grandmother, Connie Husenbuhler, who heard the news on Florida television and rushed back to Maryland. "They call her the comeback kid. It's a miracle."

Over the weekend, the comeback kid came home for a four-day visit that will include tomorrow's opening arguments. Her hospital costs have reached $250,000, paid by insurance, but she continues to recover at a brisk pace, Cline said. Since her mother saw her the previous weekend, Destiny had learned to tie her own sneakers and to cross her legs. She looks forward to continuing to lose weight "because I'm chubby," and to one day resuming her job at McDonald's.

On Saturday, Destiny was happy. A prisoner at the Maryland Correctional Institution who read that Destiny would be home that weekend sent her a new cassette player and two New Kids on the Block tapes. Her cousin, Jimmy Kimble, brought her a doll of New Kid Jordan Knight. As do other girls her age, she giggles a lot.

But there is much about Destiny that is different from most other girls -- the way her hands and arms shake as she picks up a french fry, for example. And, most strikingly, her memory, which seesaws between a jumble of names, dates and places and a precision that sometimes startles her family.

Destiny can't remember her age, but she can reel off names of her mother's old friends. She knows the names of the five members of New Kids on the Block. She can't recall if Citicorp is a restaurant or a bank.

The saddest part is that she can no longer remember how to draw. Once a budding artist whose ink sketches were detailed and exact -- this summer she was accepted into an exchange program to study in the Soviet Union -- the characters that now spill from her pen are like the crude sketches of a 5-year-old.

Yet, ask Destiny if she thinks she'll ever come to draw as she once did, and the answer is defiant: "I'll be even better."