  The generalised calibration for a wrapped membrane is gauge equivalent to the
supergravity three-form under which the membrane is electrically charged. Given
the relevant calibration, one can go a long way towards constructing the
supergravity solution for the wrapped brane. Applications of this method have
been restricted since generalised calibrations have not yet been completely
classified in spacetimes with non-vanishing flux. In this paper, we take a
first step towards such a classification by studying membranes wrapping
holomorphic curves. Supersymmetry preservation imposes a constraint on the
Hermitean metric in the embedding space and it is found that this can be
expressed as a restriction on possible generalised calibrations. Allowed
calibrations in a particular spacetime are simply those which satisfy the
constraint equation relevant to that background; in particular, we see that the
previously considered Kahler calibrations are just a subclass of possible
solutions.
