Sixty babies were divided into three groups of 20 each, one group being fed by cup, one by bottle and one by breast during the first 10 days of life. The breast fed infants developed a stronger sucking reflex than either of the other two groups, which did not differ from one another. There were no statistically significant differences between the groups with respect to amount of spontaneous oral activity or amount of crying. The breast fed group showed slightly higher general body activity in the last five days and slightly poorer appetite on the first three days.