The exceptional hyperplanes of

Abstract: In [B. De Bruyn, H. Pralle, The hyperplanes of , preprint 2005], we showed the existence of five isomorphism classes of hyperplanes in each dual polar space of type . We also proved there that every hyperplane of belongs to one of these five classes if . In the present paper, we classify all hyperplanes of and find four additional isomorphism classes of hyperplanes. [Copyright &y& Elsevier]