This study investigated the online process of reading and the offline learning from an illustrated science text. The authors examined the effects of using a concrete or abstract picture to illustrate a text and adopted eye-tracking methodology to trace text and picture processing. They randomly assigned 59 eleventh-grade students to 3 reading conditions: (a) text only; (b) text with a concrete illustration; and (c) text with an abstract illustration in a pretest, immediate, and delayed posttest design. Results showed that the text illustrated by either the concrete or the abstract picture led to better learning than did the text alone. Eye-fixation data revealed that the abstract illustration promoted more efficient processing of the text. Analyses of the gaze shifts between the 2 types of external representation indicated that the readers of the text with the abstract illustration made a greater effort to integrate verbal and pictorial information. Furthermore, relations between online and offline measures emerged. (Contains 1 note, 2 figures, and 5 tables.)