Pharmacia

(PHA)

said Chief Executive Fred Hassan will assume the additional post of chairman following the resignation of Robert B. Shapiro.

Shapiro was chairman and CEO of

Monsanto

, which merged with Pharmacia last March. He joined Monsanto in 1979, serving as head of the company's NutraSweet and agricultural businesses before becoming chairman, president and CEO in 1995.

"The speed and success of our merger, the strength of the new management team under Fred Hassan, and the exceptionally strong performance that Pharmacia is delivering, along with the successful partial IPO of the new Monsanto Company, led me to the decision that now is the time to conclude my service on the board," Shapiro said in a statement.

Board member John Reed is also resigning. Reed is the retired chairman and co-CEO of

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. He joined the Pharmacia board in March 2000 after sitting on the original Monsanto board for 15 years. He will continue to serve on the board of the new incarnation of

Monsanto

(MON)

, a recent Pharmacia spinoff.

The board's numbers have dwindled to 15 from 17 with the departure of Shapiro and Reed.

On the

New York Stock Exchange

this morning, Pharmacia, which is based in Peapack, N.J., lost 53 cents, or 1%, to $55.28. Monsanto was up 12 cents, or 0.4% to $30.30.