129 
of tlie germ would then ensue. This actually succeeded. 
After I had burst the two globular cysts (which, from the 
firmness of the hyaline cyst-membrane, required a rather 
considerable pressure) the spindle-shaped siliceous spores 
separated from each other, and dispersed themselves in the 
water. For the first two days there was no alteration and 
no movement to he observed in them. They lay irregularly 
and apparently unaltered at the bottom of the watch-glass. 
At length, on the third day', I observed that from one end 
of several siliceous spindles projected a hyaline, finger-shaped, 
rounded process, about one third or one fourth as long as the 
spindle. At the opposite end the plasma-contents of the 
siliceous covering were depressed, and a clear opening was 
here observable (fig. 18). This opening slowly grew larger, 
while the plasma at the other end expanded more and more 
in proportion. Thus, finally^, the entire homogeneous plasma- 
body of the spindle-shaped spore issued from its siliceous 
covering, contracted itself into a ball, and remained lying 
motionless in front of the empty covering (figs. IT, 20). 
The separated plasma-ball was entirely homogeneous and 
structureless, only interspersed with exceedingly fine gra- 
nules, which were not yet susceptible of measurement under 
a magnifying power of 500 diameters. 
There was also no trace of a nucleus or of a vacuole 
to be observed after the application of several reagents. The 
naked spore was, indeed, an entirely structureless sarcode 
ball. In the empty siliceous membrane there was also no 
structure to be observed. Examined by the strongest magni- 
fiers and polarized light, both in fluid and dried, the thin 
siliceous covering showed no markings on the surface. 
Whether the narrow hole through which the naked spore or 
germ-cytodc escaped from its siliceous covering pre-existed, 
or was first formed from the rupture of the plasma by dis- 
solution of the siliceous covering at the point — whether this 
hole existed at both ends of the spindle-shaped spore-mem- 
brane, or only at one end — and whether, in the last case, it was 
at the inner (central) or outer (peripheral) end of the radiating 
siliceous spindles — I was unable to determine. 
For two hours after the plasma-body of the Myxastrum 
issues from its spindle-shaped siliceous covering it remains 
lying motionless, as a naked plasma-ball, before the empty 
covering. Then its previously smooth surface becomes 
entirely covered with fine bristles (fig. 21). These bristles 
are nothing else than radial projections of the plasma, which 
gradually lengthen, and finally equal, and even exceed, the 
diameter of the central plasma-ball (fig. 22). It was soon 
VOL. IX. — NEW SER. 
i 
