In view of the fact that the chloride content of the solutions was not determined at the finish of the experiments, the only justifiable deduction from the data is that there is a substantial and significant drop in germination above 1% salt. It is also evident that Suaeda seeds are considerably less viable than those of Mesembryanthemum. In no one of the numerous experiments of various types did the per cent. germination of Suaeda rise above 30, whereas in Mesembryanthemum there were several results between 80–100%. Low viability was also recorded by Chapman (1947a) working with the northern S. maritima. As might be expected the sodium chloride operates osmotically by inhibiting the uptake of water. Seeds in the groups of experiments above which had failed to germinate after two months in 2% and 3% sodium chloride (the values may have been greater on account of evaporation) were transferred to tap water, when germination took place (Table II). Table II. Per Cent. Germination of Seeds of Suaeda and Mesembryanthemum Initial Suaeda Mesembryanthemum Salt A. B. C. D. E. 2% 6 26 63 39 7.5 3% 20 26 72 77 18 A, E. 2 lots of 50 seeds in each dish. Time: 1 month. B, C, D. 2 lots of 50 seeds in each dish. Time: 2 months. These data demonstrate that the seeds of both species are unharmed by 2% and 3% NaCl, and germination is comparable with that obtained if placed first in tap water without immersion in salt water (Table I). These results are similar to those obtained by Sussex (1949) for Aster subulatus var. euroauster. Growth and Drainage It was thought that the relatively high position on the shore occupied by Suaeda australis might be related to intolerance of water logging. Experiments were therefore carried out to test this possibility. Plants were grown in 3-inch pots and were planted so that the roots did not extend down for more than 1 ½ inches Two types of soil were used, (a) sand; and (b) salt marsh mud; and each soil was given four treatments: (i) Allowed to drain naturally and watered daily. (ii) Water maintained at ½ inch above base of pot. (iii) Water maintained at 1 ½ inches above base of pot. (iv) Water maintained at 2 ½ inches above base of pot. In treatments ii-iv the pots were kept in glass battery jars. There were three plants for each treatment. The sand and mud soil groups were placed in two separate blocks in the greenhouse. At weekly intervals growth was measured by increase in height. The experiment ran for about 1 ½ months. At its completion it was repeated using water containing first 1% NaCl, then 2% NaCl and finally 3% NaCl. The complete series was carried out for Suaeda but only the first group (pure water) had been performed for Mesembryanthemum, and these are therefore not discussed. The results for Suaeda are set out in Table III.