The Smithsonian's National Museum of Natural History announced yesterday that the body of Hsing-Hsing, the National Zoo's beloved giant panda, will be preserved and go on display early next year, even as zoo officials turned their attention to finding a replacement panda pair.

The museum, which was given the panda's skin and skeleton, will put him on display in its rotunda at first, then move him to a prominent place in a new Hall of Mammals that will open in 2003, a museum spokesman said. The museum already has one preserved panda on exhibit.

Hsing-Hsing had enthralled visitors to the National Zoo since 1972, when he and Ling-Ling, his mate, arrived from China as a gift from the government after President Richard M. Nixon's historic visit there. They were the zoo's most popular and best-known animals.

Yesterday, a half-dozen bouquets and a child's drawing were placed at the Panda House in memory of Hsing-Hsing, who was euthanized Sunday at age 28. Two officials from the Chinese Embassy came to the zoo to express condolences. On The Washington Post Web site (www.washingtonpost.com), more than 350 people posted sympathy notes.

"Hsing-Hsing for more than 25 years has been an icon not just to the American people but to visitors from all over the world," said Randall Kremer, spokesman for the Natural History Museum. "It's certainly been our feeling at the museum that we should honor the legacy of both Hsing-Hsing and Ling-Ling in some manner fitting to the contribution that they made to our understanding of the need for conservation of endangered species."

Ling-Ling died of heart failure in 1992. After some mating setbacks, the two produced five offspring, although none survived. Kremer said Ling-Ling could not be displayed because her necropsy was not done with that in mind.

The process of preparing Hsing-Hsing for display will involve placing his skin over a man-made frame that is designed to appear lifelike.

Some e-mailers to the Post Web site urged the zoo to look harder for corporate money to obtain a pair loan of pandas on loan from China. Zoo officials have offered China $2.5 million over 10 years for a breeding pair; China has asked for $8 million. Giant pandas are so rare that only 1,000 are estimated to be living in the mountains of China.

"Why not get someone to sponsor the Panda House and work from there," suggested one Web correspondent. "Does the Panda House at the National Zoo sponsored by the Discovery Channel sound so bad? It can't sound any worse than Fed-Ex Field."

The zoo's deputy director, McKinley Hudson, said the zoo's heretofore "quiet campaign" to get replacement pandas is "clearly going to be more aggressive now." But Friends of the National Zoo--FONZ, the zoo's fund-raising arm--will need "at least $1 million to pay a staff to go out and make contact with potential corporate and individual donors," he said.

Zoo supporters also have privately tried to enlist political support for getting more giant pandas, although zoo officials have not been directly involved for fear of appearing to lobby on behalf of a federal institution.

A zoo supporter tried to get a panda request on the agenda for President Clinton when he went to China last year, but it did not happen, a zoo source said.

Three years ago, FONZ officials tried to persuade Vice President Gore, a Smithsonian regent, to talk to the Chinese about a gift exchange--a pair of pandas from the Chinese in trade for a pair of musk ox or other animals from the National Zoo. Gore's staff was reluctant because at the time there was no U.S. panda import policy in place, the zoo source said. A policy took effect last year.

Also yesterday, the zoo's pathologist said a postmortem examination of Hsing-Hsing found multiple problems in addition to the advanced kidney disease that had severely weakened him, including an enlarged heart and a possibly cancerous stomach mass the size of a tangerine.

They said the examination reaffirmed their decision to euthanize the panda and left them amazed he had survived for so long.

"Hsing was an incredibly hearty bear," said Richard J. Montali, the zoo's chief pathologist, who left yesterday for a 10-day trip to China to teach a veterinary workshop. "He really had an incredible amount of things going on."

He said it will be four to six weeks before laboratory test results are available to paint a fuller portrait of the panda's physical condition, including whether the stomach mass was an extension of the testicular cancer he suffered two years ago or simply benign. Also participating in the necropsy were scientists from the Armed Forces Institute of Pathology and the Museum of Natural History.

Zoo officials said Hsing-Hsing's kidney disease, diagnosed in May, was causing him to suffer so much that it was more humane to put him to death. The panda also had arthritis, failing sight and nosebleeds. His health had declined dramatically over the past week, and he could barely move.

Montali said the postmortem examination and blood tests confirmed that "euthanasia was the right thing to do at this point. . . . The sum total definitely explained his continual deterioration and the need for euthanasia."