229 
is much more universally known), in order finally to bring the 
" errors ” of other naturalists to market as his discoveries. If 
Reichert should live to the year 18S0, for the good of science, 
he would then probably arrive at the present already univer- 
sally known facts of the structure of the Coelenterata. I have 
continually busied myself, as it happens, for the last few 
years, with the examination of the finer structure of the 
Hydromedusae, and am therefore justified in asserting that 
nearly all Reichert’s new statements as to the structure of the 
Hydroidae are just as confused, erroneous, and worthless as his 
former statements as regards the structure of the Polythalamia. 
One will forgive the acrimony of this controversy and excuse 
it, owing to the just anger which I must experience as the 
grateful pupil and ardent admirer of the great Johannes 
Muller, when I think of these extravagances of his imme- 
diate successor. The anatomical chair of the University of 
Berlin was raised during a quarter of a century above all 
others by Johannes Muller, and as Muller terminated the 
long series of his illustrious works with the Rhizopoda, 
Reichert probably thought he must begin where his great pre- 
decessor had left off, and was apparently actuated by the 
hope at once to surpass him ! How far he has succeeded 
in this is manifest to all who know the literature which 
contains it, and have examined the objects themselves in 
nature. 
The Protoplasm-theory, which I consider as one of the 
first and most important foundations of a truly monistic, i. e., 
mechano-causal knowledge of organic nature, may be consi- 
dered as newly confirmed and strengthened by this last turn 
in its history. The attacks of its opponent, threatening annihi- 
lation, are gradually converted by the same man into mis- 
representations, and finally into confirmations. But for the 
true nature of the Sarcode as a truly simple and structure- 
less “ life-material,” the natural history of the previously 
described Monera may furnish further direct proofs. 
IV. The Limits of the Protista. 
Since Charles Darwin revived the theory of descent 
originated by Jean Lamarck and Wolfgang Goethe from 
the oblivion of half a century to fresh life, and placed it 
by his theory of natural selection on an unassailable causal- 
mechanic foundation, the problem of systematic arrange- 
ment has become a very different and immeasurably higher 
one. Hitherto, this was a scientific game in the hands 
