The nature of the hindlimb posture and gait of pterosaurs has been controversial(1-16), partly because most of the pterosaur skeletons that have been found were flattened in thin-bedded rocks, therefore obscuring three-dimensional anatomy. A major controversy concerns the extent to which pterosaurs move on the ground; they have been variously interpreted as ranging from sprawling, quadrupedal walkers to erect, bird-like bipedal cursors(1). Study of pelvis and femur material from the derived group Pterodactyloidea(11-13) has resolved which movements are possible at the hip, but the lack of three-dimensional, articulated pterosaur feet has prevented examination of all of the movements that are possible within the foot. We have found a large, uncrushed, partial skeleton of a new species of the basal pterosaur Dimorphodon in thick-bedded deposits of Tamaulipas, Mexico; this material includes such a three-dimensional foot, The nature of this skeleton contradicts an important part of the cursorial interpretation, that is, that only the toes contacted the ground during terrestrial locomotion(2-7). The flattened metatarsal-phalangeal joint at the base of the first four toes of this specimen would not allow such a digitigrade posture without separating most of the joints. A hat-footed stance is consistent with presumed footprints of pterosaurs(8-10) that show impressions of the entire sole of the foot.