CAMBRIDGE, Mass. – Hugh Stubbins Jr., an architect who often used his cocktail napkins to sketch designs for buildings such as Manhattan’s Citicorp Center, Boston’s Federal Reserve Bank or Congress Hall in Berlin, has died. He was 94.

Stubbins, who died Wednesday of pneumonia at Mount Auburn Hospital in Cambridge, designed buildings that now stand coast to coast: from the Senior Center at Bowdoin College in Brunswick, Maine, to PacWest Center in Portland, Ore. He also designed Landmark Tower in Yokohama, Japan’s tallest building; the Ronald Reagan President Library in Simi Valley, Calif., and Veterans Stadium, the home of baseball’s Philadelphia Phillies and football’s Philadelphia Eagles which was torn down two years ago.

“I remember seeing many napkins with the basic design of Citicorp on them, just in doodles,” his son, Hugh Stubbins III, told The Boston Globe.

Among his many honors was the Gold Medal for Excellence in Design from Tau Sigma Delta, the National Honorary Fraternity for Architecture and the Allied Arts.

Born in Birmingham, Ala., he graduated from the Georgia Institute of Technology and received a master’s degree in architecture from the Graduate School of Design at Harvard in 1935, where he later taught. He also founded The Stubbins Associates architectural firm. In retirement, Stubbins divided his time between Cambridge and Ocean Ridge, Fla.

In addition to Hugh, he leaves two other sons, a daughter and nine grandchildren.