On superspace supergravity in ten dimensions

Off-shell N=1, d=10 supergravity splits into a (128+128)-component multiplet and two scalar superfields. A concise formulation of the superspace contraints corresponding to the (128+128)-multiplet is given and the incorporation of the dimension - 6 scalar superfield discussed at the linearized level. The second scalar superfield, whose leading component is the physical dilaton field, may be regarded as being external to the superspace geometry. An action for the full non-linear theory is proposed.