622 The American Naturalist. [August, 
fauna and flora of ditch water. It was a surprise to find that 
dried egg albumen stained or ingested with litmus and Congo 
red, under these new conditions, was as a rule promptly dis- 
solved in the vacuoles, taking from 5-24 hours for completion 
of the digestive act. The same occurred with stained globoids 
of aleurone grains of ricinus and with stained torule. These 
experiments were repeated many times on many different 
individuals, and though food ingesta were occasionally observed 
in astage of storage, this was the great exception. . 
The scarcity of storage vacuoles in such plasmodia that had 
been kept in clear water for nearly a week and given oppor- 
tunity to disgorge the debris with which they were loaded 
was conjectured might be brought about by two factors : 
(1) The first was that the process of clearing and transfer- 
ring them to distilled water (in which they do not thrive as 
well as in Pasteur’s fluid with } % Na cl) the organisms had 
been starved and in a sense were too hungry to store food par- 
ticles, but went to work at them immediately. There is no 
method conceivable by which such a supposition could be put 
to experimental test, for which reason it cannot be contradicted 
or prov 
` The second supposition was that (2) absence of storage vac- 
uoles might be caused by absence of bacteria, for in their nor- 
mal environment the Protozoa are generally in close company 
with swarms of Bacieriwm termo, zooglea of micrococei and 
manifold spirilli and other schizomycetes, and by cultivation 
they had been brought into an almost aseptic, sterile environ- 
ment. 
The latter hypothesis is capable of experimental testing. 
For if bacteria will produce the phenomenon of storage then 
the supplying of septic food will be all that is requisite to add 
to the sterile solution. Asa matter of fact it will be found 
that this is exactly what will happen. In a plasmodium that 
had shown 8 storage vacuoles in 24 hours of observation in 
a solution of } % sodium chlorde (in distilled water) in which 
it had been kept one week, 48 storage vacuoles were observed 
in the next 10 hours on supplying dried albumen dust, 
moistened with the zoogloea from a Hay infusion. 
