The federal court jury deliberating over the fraud and conspiracy case against Mary Treadwell failed for the 16th day yesterday to reach a verdict but said it was still making progress.

The jury of eight women and four men considered the case for eight additional hours, extending its increasingly lengthy deliberations record for a federal court case here to 126 hours.

After working until 10 p.m. Wednesday, the jurors asked U.S. District Judge John Garrett Penn to allow them to recess at 6 o'clock last night. The judge told them to resume at 9 a.m. today.

In their only note of the day to Penn, the jurors said they were continuing to make progress, the same message the jury gave the judge Wednesday when he asked for a brief progress report. They gave no details on the extent of their progress.

Treadwell, 42, is accused of using P.I. Properties Inc., her now-defunct real-estate firm, to defraud the federal government and the low-income tenants at the Clifton Terrace apartment complex of thousands of dollars to enrich herself. She is charged with 21 counts of conspiracy, fraud, tax evasion and making false statements to two federal agencies.