In the absence of a complete system of notification, which the Committee consider is urgently necessary, any estimate as to the number of feeble-minded to be dealt with must be largely a matter of conjecture. From the annual report of the Education Department, however, interesting information is available showing the ages of the pupils in the several classes of the primary schools. The following table is considered worthy of reprinting in this report, for from the figures it supplies some idea may be formed of the number of backward and feeble-minded children attending primary schools. Children of extremely low-grade mentality do not attend school as a rule, while feeble-minded children higher in the scale, discouraged by the unsuitable course of instruction and lack of sympathetic treatment, tend to leave school early. Hence the number of feeble-minded children in any community must be considerably larger than the school records indicate. The following table shows the ages of pupils in the several classes of the primary schools. The numbers between the heavy horizontal lines represent those that, beginning school under six years of age spend an average of two years in the preparatory classes and one year in each of the standards. The numbers above the upper heavy lines have progressed at a greater rate than that indicated, and those below the lower lines have either begun school later or have progressed more slowly. The most arresting feature in the table (p. 13) is the large number of children in classes lower than should be expected at their age. Thus the preparatory classes had 12,693 pupils over the age of eight years. This number is certainly a considerable reduction on the total for the previous year, but it still represents no less than 18 per cent. of the total roll of those classes. Particular attention is being directed to the problem of retardation, and in some of the larger centres special classes for retardates have been established. It will also be seen that the actual number of children retarded three years or more, including the preparatory classes and up to Standard III--beyond which the higher grades of the feeble-minded do not progress as a rule--is 4,917 out of a total of 212,709 children attending school, or a trifle over 2 per cent. In some countries three years' retardation is regarded as _prima facie_ evidence of mental deficiency. Probably New Zealand has much the same proportion of mental defectives as other countries. This is stated by Goddard to be between 2 and 3 per cent. of the population.