254 DR. DUFFIN, ON PROTOPLASM. 
filaments, as Reichert himself admits—that this has little 
more refracting power than the surrounding water. Granules 
which project literally from a thread pass into luminous points 
when the tube is lengthened beyond that position im which 
the movements are best observed. 2. With a high power it 
will be seen that many of the granules circulating in the 
threads of the Miliolides have an oval or staff-like shape, and 
although the majority of them have their long axis parallel 
to that of the thread, they not unfrequently he at right 
angles to some, only to roll over as they move onwards. In 
short, these bodies often rotate, and this proves their corpus- 
cular nature. 3. Reichert argues that the granular appear- 
ance vanishes whenever the threads are extended in a quies- 
cent state, but Schultze notices the extreme rarity of this 
phenomenon, and asserts that, however thin the filaments, 
seldom more than a second passes without a granule coursing 
along it from some neighbouring thread. These extended 
fibres in a quiescent state are just those that show the most 
vivid play of the granule circulation. Frequently a few 
granules may be seen to rest for a short while, as at the so- 
called bridges, when these chance to stand at right angles 
to the filaments they happen to unite. By artificial means 
the granules may be brought to rest over considerable tracts 
without, as Reichert supposes, any disappearance of them. 
If a drop of distilled water be placed at the margin of the 
glass covering an animal with its pseudopodia extended, the 
movement of the granules becomes sluggish, and ultimately 
stops without any other change being noticed in the filament ; 
the granules are as distinct and numerous as before; the 
basic substance appears totally unchanged. Should the in- 
fluence of the distilled water be continued, small vacuoles 
appear in the substance of the filament, enlarge, spread, and 
acquire a frothy appearance, till the whole is destroyed by 
the increasing phenomena of imbibition. Similar results 
may be obtained from solutions of iodine, weak acids, or 
alkalies, and the electric current. ‘The objection that the 
phenomena of coagulation disturb the observation is met by 
the following experiment. If an animal with extended 
pseudopodia be crushed so that its capsule bursts and the 
contents are extruded in dense masses, the extended threads, 
wherever they are not mechanically incommoded, lie un- 
changed, and retain their characteristic movements for a 
while. Although their connection with the body of the 
animal has been in many cases severed, the circulation of 
the granules persists. But it becomes more and more tardy, 
the filaments contract more and more to dense networks or 
