Hand gestures in face-to-face dialogue are symbolic acts, integrated with speech. Little is known about the factors that determine the physical form of these gestures. When the gesture depicts a previous nonsymbolic action, it obviously resembles this action; however, such gestures are not only noticeably different from the original action but, when they occur in a series, are different from each other. This paper presents an experiment with two separate analyses (one quantitative, one qualitative) testing the hypothesis that the immediate communicative function is a determinant of the symbolic form of the gesture.