The space of nodal curves of type p,q with given Weierstraßsemigroup

Abstract: We continue the investigation of curves of type p,q started in [KKW]. We study the space of such curves and the space of nodal curves with prescribed Weierstra\ss semigroup. A necessary and sufficient criterion for a numerical semigroup to be a Weierstra\ss semigroup is given. We find a class of Weierstra\ss semigroups which apparently has not yet been described in the literature.