20 
ANIMAL INTELLIGENCE. 
to show that the rhizopod distinguishes the presence of 
the sawdust outside the watch-glass, and crawls over the 
brim of the latter in order to get into more congenial 
quarters, while it is contented with the water in the watch- 
glass so long as there is no sawdust outside. But to pro- 
ceed: 
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 similarly shaped 
grains of starch in their interior , and having determined the 
nature of these grains in both 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 acti- 
nophrys 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 dis- 
tance. 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 upon 
a filament of Spirogyra crassa ; and as the young ciliated 
monadic germs issued forth, one after another, from the dehis- 
cent 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 
