1885.] Comparative Physiology and Psychology. 13 
If the Amceba had undergone differentiation above some form by 
which it was engulfed, it could be regarded as the male. If it 
were swallowed by a synameeba then it is the female cell, and the 
product of this sexual eating would be either male or female— 
synamceba or amoeba according to the preponderance of differen- 
tiating influence or the disposition to increase by fission on the 
resulting fused mass. 
Desires consisting of atomic tensions or affinities, the condi- 
tions of continuance or satisfaction of desire, involves feeling or 
sensation, a low form of consciousness; this is justified in consid- 
ering our developed similar states during the same processes of 
hungering, eating, etc., and as in us repletion discontinues desire, 
so does it in the lowest form of life we are discussing. 
The sensations involved in assimilation would be difficult to 
separate from those concerned in pseudopodia-protrusion or gen- 
eral locomotion, as they are identical in effect in the Ameeba; 
admitting their identity, it is easy to see how, by invagination of 
the ectoderm the later differentiation could occur by an enteric 
tactile developing in one direction while the ectodermal would 
change with direct reference to locomotion or prehension. But, 
as even when the enteron is formed, a prehensile tactile sense is 
retained and developed, analogies between the same distributions 
to external and internal parts remain though the sensations in 
many respects differ. The passage of materials in the intestines 
- awaken few feelings so long as the adjustment is not disturbed, 
on the same principle that we do not feel external ordinary stim- 
uli perpetually recurring. 
Pressure is the feeling of constraint, a with molecu- 
lar and mass movement, it is a painful state of consciousness 
arising from the inhibited movements, the desire to move being 
consequent upon proper assimilation, and is referred to an inter- 
ference with that function. 
The hunger pain and appeasing hunger pleasure are due to and 
consist in chemical tensions and release from tension, the absence 
and presence of certain molecules. This carried up the scale of 
Metazoa convinces us that desire, feeling, sensation reside im every 
living cell in the body, and are not seated exclusively in nerve 
tissue. With the differentiation of function there will proceed 
changes of degrees of intensity of certain feelings in those living 
cells, but the fundamental hunger pain and pleasure of its gratifi- 
cation are never differentiated out of existence in any cell. 
