  Riemann's minimal surfaces are a complete, embeddable, one-parameter family
of minimal surfaces with translational symmetry along one direction. It's
infinite number of planar ends are joined together by an array of necks,
closely matching the morphology of a bicontinuous, lamellar system with pores
connecting alternating layers. We demonstrate explicitly that Riemann's minimal
surfaces are composed of a nonlinear sum of two oppositely-handed helicoids.
This description is particularly appropriate for describing smectic liquid
crystals containing two screw dislocations.
