The final result is that we can write each of these mock theta-functions as the sum of two functions ? and G, where: - ? is a real-analytic modular form of weight 1/2 and is an eigenfunction of the appropriate Casimir operator with eigenvalue 3/16 (this is also the eigenvalue of holomorphic modular forms of this weight); and - G is a theta series associated to a negative definite unary quadratic form.