The effects of manipulating two parameters of legibility; matrix/character size and font, on two performance measures, reading times and eye movements, were studied in this experiment. The results showed significant practice effects for the 7 x 9, 7 x 9 (= 5 x 7), and 9 x 11 (= 5 x 7) sizes. The data also showed that the size of a character had some effect on both the duration of fixations and the duration of saccades. There was little or no correlation among the response measures of eye movements, tachistoscopic recognition, and reading times. / M. S.