222 
indigo grains into their interior. Probably the above-mentioned 
fine grains were at least in part also drawn into the interior 
of the body from the surrounding fine mud. In any case, the 
taking of these small solid bodies proceeds as in the true 
Amoebae, and as in the Amoeba- like blood-cells of animals, by 
means of the peculiar motion of the pseudopods, without a 
permanent opening or hollow receptacle ever being present 
in the solid slime-mass of the body. 
Already, when, in 1863, for the first time, I observed the 
Protamoeba, I concluded that it multiplied itself simply by 
division, for the individuals contained in a small glass in- 
creased remarkably in a few days, without any changes or 
transition to a passive condition ever having been observable 
in these very simple organisms. When I again found the 
Protamoeba two years afterwards in the same pond near 
Jena, I tried by continued observation of single individuals 
to establish the nature and manner of its reproduction, and 
this actually succeeded. Several Protamoebae showed in the 
middle of their body a more or less deep constriction, thus 
becoming more or less biscuit-shaped (fig. 27). The constric- 
tion continued, without affecting the changes of form which 
took place in each of the two halves of the body ; and it 
became perceptibly deeper (figs. 28, 29). At last I succeeded 
in directly establishing the actual division of the contracted 
portion, and the complete separation of the two divided 
halves, in two individuals which I had constantly observed 
for a considerable time (fig. 30 a b). Each half immediately 
rounded itself, and then uninterruptedly continued the former 
slow movements. Thus was established in Protamoeba the 
simplest form of non-sexual reproduction, i. e., by division, 
and without being preceded by a passive state. Manifestly 
Monera such as Protamoeba primitiva may be considered to 
occupy the first place in the hypothesis of archigony or spon- 
taneous generation. 
III. — Remarks on the Protoplasm Theory. 
The Monera which I have just described, Protomyxa, 
Myxastrum, Myxodictyum, and Protamoeba, as well as Proto- 
genes, which I formerly described (1. c.), and Protomonas and 
Vampyrella, observed by Cienkowski, all perfectly agree in their 
whole bodies consisting when completely developed, and in 
their freely moving condition, of a structureless and thoroughly 
homogeneous substance. In all chemical and physical respects 
this substance shows the qualities of a consistent carbonaceous 
compound of the group of albuminous substances (Proteine). 
