The equations which govern the similarity solution for free convection boundary-layer flow above a permeable, horizontal surface in a fluid-saturated porous medium are considered. These are seen to depend on the dimensionless parameters gamma and m measuring mass transport rate and the wall temperature variation, respectively. Numerical solutions are presented for a wide range of values of gamma and m. Asymptotic solutions are obtained for \gamma\ large (for both fluid injection, gamma > 0, and fluid withdrawal, gamma < 0) and for m large. These are compared with the numerical solutions.