The algae in the Fucales are characterized by:

Their parenchymal growth (i.e. growing in three dimensions rather than as a two-dimensional filiment), outward from an apical area at each apex.

Their reproductive organs are always contained in conceptacles, usually on the tips of the thallus (body of the aglae).

Their life cycle is almost completely diploid, with only the gametes being haploid.

Their eggs are large and non-motile, and are fertilized by small motile sperm (oogamy).

(Rousseau and DeReviers 1999)