438 MR. A. LISTER ON THE INGESTION OF FOOD-MATERIAL 
as six or seven, attached to the pseudopodia produced from the 
posterior extremity. Shortly after, many vacuoles were seen to 
contain foreign matter. 
I dried several drops of the preparation and stained with 
magenta, and mounted in balsam ; the mountings showed deeply- 
stained bacilli, principally in a large vacuole near the nucleus. 
Next day I wetted another dusting of spores, and in a couple of 
hours, when the pure water was thickly peopled with swarm-cells,. 
I added a drop of the water crowded with bacilli; as on the 
previous occasion, bacilli were soon observed attached to the 
rugged posterior region, and others were seen enclosed in 
vacuoles. I watched one swarm-cell with a wriggling bacillus 
adhering to a delicate pseudopodium; it was gradually drawn 
inwards as the pseudopodium contracted. I then saw an exten- 
sion of protoplasmic matter fold over the bacillus, and absorb it 
into the interior substance ; shortly after I saw it conveyed into 
a large vacuole near the nucleus, which already contained three 
bacilli. I watched these for an hour; they gradually became 
more and more indistinct, until nothing was visible but a faint 
indefinite residuum. No fresh bacilli were taken in during this 
time. 
In the next observation a bacillus 5 p in length was attached 
to a pseudopodium so extremely fine, that its continuity could 
only be determined by the violently moving captive indicating 
the distance to which the thread extended. In the course 
of a few minutes the bacillus was drawn inwards, and, as in the 
former case, an extension was folded over it, and it was taken 
into the interior, where it was soon surrounded with a vacuole; 
another large vacuole containing two other bacilli was stationed 
near the nucleus, but during the twenty minutes it was under 
observation the two vacuoles remained distinct. In another 
instance, when a large bacillus was caught by a pseudopodium 
and drawn up to the main body, a tube-like process was extended, 
investing it almost to its extremity ; the bacillus was then sucked 
1n, and as it lay athwart the swarm-cell in a large vacuole, it was 
of so great a length that the ovoid cell was bulged out on each 
side by the stiff rod; a violent jerking movement followed, such 
as I have repeatedly noticed after the ingestion of food, and in a 
few minutes the bacillus was bent double, the vacuole decreased 
1n size, and in a quarter of an hour its contents had become less 
distinct. by the process of absorption. (See figs. 1-6, p. 440.) 
