  We derive simplified normal forms for an area-preserving map in a
neighbourhood of a degenerate resonant elliptic fixed point. Such fixed points
appear in generic two-parameter families of area-preserving maps. We also
derive a simplified normal form for a generic two-parametric unfolding. The
normal forms are used to analyse bifurcations of $n$-periodic orbits. In
particular, for $n\ge6$ we find regions of parameters where the normal form has
"meandering'' invariant curves.
