THE barrel of the Confederate 12-pounder howitzer was missing, and so was the saddle on which Jefferson Davis rode into the Mexican War. Four days after Katrina, Patrick Hotard's face was shadowed with exhaustion and dismay as he surveyed what was left of Beauvoir, the beachside Jefferson Davis home and presidential library, where he is the director. He had just arrived from his refuge in Louisiana, and many of his worst fears were being confirmed as he picked through the bricks, giant wafers of plaster and nylon Confederate flag replicas.

Some $220,000 had just been spent renovating the graceful gallery porches and the entrance doors, each with its nine oval panes, of the 1852 Greek Revival house where Davis, the Confederate president, spent his last 12 years. Those features are now either gone or in ruins, along with two original porch-wrapped cottages, a replica of a Civil War barracks and the entire first floor of the presidential library.

Mr. Hotard is one of the many curators, archivists and preservation advocates who are beginning to tally the losses in the areas hardest hit by the hurricane, even as emergency workers turn to the more essential tasks of gathering the dead and providing supplies. For preservationists in Mississippi no less is at stake than the region's architectural patrimony.

In Mississippi's Gulf Coast counties alone, Katrina plowed through 15 historic districts and over 120 individual properties that are listed on the lesser National Register of Historic Places, as well as scores of other historically important buildings that were not nationally recognized.

Although Mississippi's oldest building is still standing (a 1720 plantation home called the Pointe-Krebs House on the coast in Pascagoula), historic neighborhoods in Bay St. Louis and Waveland were flattened.