Sends final results of his experiments on the vitality of various kinds of seeds immersed in sea-water. Corrects a false assumption he made in an earlier letter [1684] that plants with ripe seeds would float for some weeks. Now finds that they sink within a month. Since all the seeds he tried sank in sea-water, his experiments are of little or no use "in regard to the distribution of plants by drifting of their seeds across the sea".