A federal district court jury in Boston failed to reach a verdict last night after being charged in a suit to determine whether the Wampanoag Indians of Mashpee, Cape Cod, are legally a tribe.

Judge Walter J. Skinner finished charging the eight-man, four-woman jury at 3:02 p.m. yesterday, and the jury will continue deliberating today.

The Indians are seeking title to 13,000 acres of village land, valued at $30 million, they maintain was taken from them in violation of a 1790 federal statute.

Issues and Answers

The issue in the 10-week trial is whether the Indians constitute a tribe that can legally press its claim in a federal court. A verdict in favor of the Wampanoags would allow them to follow through on a second suit that could give them title to the disputed land.

James D. St. Clair, former attorney for former President Richard M. Nixon who is now representing the town of Mashpee, said in his final argument Tuesday that the Indians only are the descendants of the "remnants of other tribes" who converted to Christianity, shed their tribal affiliations and settled in the Cape Cod seashore community, in the 1660's. Lawrence D. Shubow, attorney for the Indians, summed up his case Tuesday saying, "Don't deny these people their identity. They have been fighting for this identity for 350 years. Are you going to say 'You've been a living fraud?"