Rats of Sprague-Dawley strain were fed a liquid ethanol diet that was nutritionally balanced and provided 35% of calories as ethanol. Control animals were pair-fed and received the same liquid diet with maltose-dextrins substituting for ethanol. At birth the pups of both the experimental and control groups were fostered by surrogate mothers which received normal rat chow ad libitum. An average of eight alcohol-fed and eight pair-fed pups were killed at 0-1, 5, 7, 10, 14, 21, 28, and 42 postnatal days. The fixed cerebella of these pups was bisected in the midvermal plane and one-half was embedded in paraffin and the other in Araldite. Projection drawings of hematoxylin and eosin-stained paraffin sections were made at 50X magnification. Using the graphics plate of an Apple II computer, the circumference and area of the vermal cerebellum was determined. We found that at all the time sequences studied the area and circumference of the cerebellum were significantly reduced in ethanol-exposed pups compared with the pair-fed controls.