"On one occasion, while investigating the nature of some large, transparent, spore-like elliptical cells (fungal?) whose protoplasm was rotating, while it was at the same time charged with triangular grains of starch, I observed some actinophorous rhizopods creeping about them, which had similar shaped grains of starch in their interior; and having determined the nature of these grains by the addition of iodine, I cleansed the glasses, and placed under the microscope a new portion of the sediment from the basin containing these cells and actinophryans for further examination, when I observed one of the spore-like cells had become ruptured, and that a portion of its protoplasm, charged with the triangular starch grains, was slightly protruding through the crevice. It then struck me that the actinophryans had obtained their starch grains from this source; and while looking at the ruptured cell, an _actinophrys_ made its appearance, and creeping round the cell, at last arrived at the crevice, from which it extricated one of the grains of starch mentioned, and then crept off to a good distance. Presently, however, it returned to the same cell; and although there were now no more starch grains protruding, the _actinophrys_ managed again to extract one from the interior through the crevice. All this was repeated several times, showing that the _actinophrys_ instinctively knew that those were nutritious grains, that they were contained in this cell, and that, although each time after incepting a grain it went away to some distance, it knew how to find its way back to the cell again which furnished this nutriment.
"On another occasion I saw an _actinophrys_ station itself close to a ripe spore-cell of _pythium_, which was situated on a filament of _Spirogyra crassa_; and as the young ciliated monadic germs issued forth one after another from the dehiscent spore-cell, the _actinophrys_ remained by it and caught every one of them, even to the last, when it retired to another part of the field, as if instinctively conscious that there was nothing more to be got at the old place.
"But by far the greatest feat of this kind that ever presented itself to me was the catching of a young _acineta_ by an old sluggish _amoeba_, as the former left its parent; this took place as follows: