A Previous paper by Carroll in 1933 described the results of research on the potato eelworm in the Irish Free State up to the year 1932. The table on p. 145 of that paper sets forth the four series of pot experiments which were carried out in 1932 and shows the degree to which the various pots in the different series were artificially infected (before planting) with eelworm cysts for the purpose of the experiments. In assessing the degree of potato sickness which developed in these pots and outlining the results of the experiments, reference was made to the following points:—appearance and size of the overground parts of the plants; degree of development and nature of the root system; presence or absence of different fungus diseases; abundance of eelworm cysts on the roots (as far as could be judged by a visual examination); weight of tubers produced. Before the paper went to press, the actual cyst content of the soil in the different pots at the end of the growing season had not been determined. That has since been done and the figures are presented in Table I on the following page.