Milk productions and 7 d dietary records were determined on twenty-seven mothers who had been breast-feeding for 1, 3, 6, 9, 12 or 15 months. 2. The mean milk productions for each group of mothers was 1 . 87, 1 . 238, 0 . 884, 0 . 880 and 0 . 951 kg/24 h at 1, 3, 6, 9, 12 and 15 months of lactation respectively. There was no significant difference between two milk determination 3--7 d apart on each mother or between the mean milk production of each group of mothers. 3. Energy intakes of the infants was found to be higher than the usually-accepted values at 1 and 3 months of age but by 6 months were similar to the accepted normal values. 4. Energy intakes of the mothers although greater than those recommended for similar non-lactating women were not sufficient to take into account the energy content of the milk.
