89 
TV. 
The ce//-scud is therefore a perfectly general manifestation of 
organised life ; the sowd-cell, on the contrary, a special one. No 
doubt our conception of the cell-soul is by no means yet universally 
recognised, and is energetically contested even at present by 
eminent authorities, e.g., Von Virchow. But on the firm ground 
of the development theory of modern times, due to the reformation 
introduced by Darwin, we must maintain that our “theory of the 
cell-soul” is as much a necessary as it is an important consequence 
of the unitary or monistic conception of Nature. We must there 
fore accordingly be allowed to cast a hasty glance at those lowest 
groups of beings, which most especially seem to us to bear witness 
to the truth of this pregnant theory. 
Deep down on the lowest step of organised life, midway in 
between the limits of the animal and plant kindoms, and most 
closely uniting both great kingdoms, lives and works that wonderful 
world of microscopic organisms, invisible to the naked eye, which 
are generally designated as primeval infusoria, or protozoa. The 
great majority of these protozoa remain their whole life in the 
form of a simple single cell, and nevertheless this cell confessedly 
possesses alike sensation and voluntary motion. In the lively 
“eye-lash” or ciliated animalcules—the infusoria—these soul- 
activities are exhibited in so surprising a degree, that the famous 
investigator of infusoria, Ehrenberg, unhesitatingly and with the 
greatest certainty maintains that even here there must be present 
nerves and muscle, brain and mind organs. And yet as a matter 
of fact, not a trace of any such things appears. The sole and only 
material supporter of the soul-life here is the protoplasm of the 
cell-body, the substance containing within it the cell-nucleus, 
forming a soul-apparatus of the simplest kind. And if we but 
once become convinced that already among these single-celled 
infusoria there are very different characters and temperaments— 
clever and stupid, strong and weak, lively and dull, light-loving 
and light-avoiding individuals—we find that we can account for 
