An improved curtain wall casing bead for installation on buildings having stucco or similar curtain wall exteriors. The improved curtain wall casing bead incorporates a mesh attached to at least the base portion of the casing or starter bead, which mesh extends beyond the front edge of the base, and, when folded upward over the face of an inserted foam or curtain wall panel, provides additional area for the infiltration of over-applied stucco finishes or the like. Such additional infiltration, after drying of the over-applied layer provides a more adherent, higher quality and more durable attachment of the stucco finish to the casing bead and the overall wall structure is achieved.