Identification of figural elements is based upon comparison of one of several formal pattern descriptions with subjective similarity judgements. The best description appears to contain figural elements which are heavily dependent on the visual domain chosen for the experiment. Generally those figural elements seem to be involved which distinguish optimally between the reference patterns used to mark off the visual domain. An algorithm is proposed for searching figural elements which are building stones of optimal descriptions. The present study indicates that grammars generating structures based upon features, higher order figures and rules of composition may be tools for visual research.