This study investigated hand activity on the surface of an object whose tactual texture was heterogenous, but not discernible visually. Infants from 4 to 6 months of age were allowed to touch and explore a horizontal cylinder, whose surface had regular smooth and rough parts. Results showed that contact was not continuous and was mainly unimanual at every age. The direction of cumulative contact time did not increase with age, but contacts were characterized by more and more action. As early as 4 months, the predominant exploratory procedure was raising with the fingers, performed more often by the right hand while the left hand performed more passive contact. From the 5th month, raising movements were made by both hands, in alternation. There was no overall preference observed for texture quality. The right hand remained more on the rough part than on the smooth parts, whereas the left hand performed more raising on the boundaries. These data showed that infants are active in perceiving textures by touch of the object before the age of 6 months and confirm that young infants are able to use an adapted manual exploratory procedure. '1997