A 17-year-old girl came to the District four months ago, hoping to find a job and a new life after leaving her parents' home in rural Virginia.

She lived here with friends and relatives until two months ago, when she moved in with a 21-year-old clerk who lived in an abandoned three-story rowhouse on 18th Street near Columbia Road NW.

Early Wednesday morning the girls' new life turned to tragedy when, after leaving her eight-month-old son unattended for close to eight hours, she and her boyfriend returned home and found trhe child unconscious.

The baby was pronounced dead by physicians at D.C. General Hospital at 6:45 a.m. Wednesday. On Thursday the girl was charged by D.C. police in the juvenile division with wilful neglect, pending final results of an autopsy.

She pleaded not guilty to the charge at a hearing at Juvenile Court yesterday and returned to her parents' Virginia home. Her attorney, David Sitomer, and his client has grown silent and moody. "She didn't say very much at all" after the hearing, Sitomer said.

"What the Court is trying to do. I think," Sitomer continued, "is rehabilitate her by shaking her up a bit and showing her where she went wrong. The distinction between intent and neglect is very thin in matters like this."

According to Dr. Leroy Reddick, assistant D.C. medical examiner, an examination of the baby's body revealed no bruises or evidence of malnutrition. Reddick refused to say, pending completion of laboratory tests, what the cause of death might have been.

Pat Elliott, secretary to William Barr, director of the protective services division of the D.C. Department of Human Resources, said that the baby's death could possibly have been avoided had either the boy's mother or someone else notified the agency.

"It's a shame," she said, "that we don't know about cases like this sooner. Someone, anyone, can approach us and we'll help. But some people just don't know about and avail themselves of our services. What can you do?"

Elliott said that protective services "could have put the child in a foster home, temporarily, until (the mother) was able to find a job. We have contacts with housing facilities in the area where she could have stayed. We could have gotten her into the food-stamp program and helped her apply or public assistance funds."

But, for all that, the tragedy occurred and the baby is dead. Only traces remain of the young mother and child who came here four months to seek a new life.

In the third-floor apartment where they lived, plies of clothes and diaper boxes lie in corners, dust and cigarette butts obscure the wood floor. Milk shake cups and half-eaten sandwiches remain stacked with the rest of the garbage by the far wall.

The apartment remains without light or water, and green plant continues to peel off the walls near the boxes of rat poison on the floor. The temperature in the room is still in the 90s, as it was the night the baby died.

Outside the abandoned rowhouse where the mother, her baby and her boyfriend lived, sheets of plywood, pasted over with faded political posters, cover the windows. A broken padlock guards the front door.

The young mother will return to Washington for trial on Aug. 15. her baby will be buried in Virginia today.