172 
PHYSIOLOGY: C M. CHILD 
This view also affords a basis for the interpretation and synthesis of 
the data of regeneration or form regulation which have stood heretofore 
as curious and remarkable facts, but without any adequate underlying 
general conceptions or working hypotheses. With this conception of 
the individual these data fall readily into line and many of them support 
and confirm it in a very definite way. 
From this point of view the development of the nervous system as a 
conducting and correlating system and of its functionally dominant 
cephalic region are less completely mysteries than they have been, for 
we can see that they are the final results of conditions which existed at 
the first moment of individuation, and that the physiological integration 
of the organic individual is always fundamentally a relation of domi- 
nance and subordination. In the lower organisms and the earlier de- 
velopmental stages of the higher, individuation approaches more or less 
closely to that type of social individuation which we find in the tribe or 
in certain forms of the primitive state, while in the later stages of devel- 
opment of the higher animals there are many indications of an approach 
toward democracy in the organism. 
References to previous work by C. M. Child. 
^ Physiological Isolation of Parts and Fission in Planaria. Arch. Entwickelungsmech., 
30 (Festbd. f. Roux), Teil 2 (1910). 
* Die physiologische Isolation von Teilen des Organismus. Vortr. Aufs. Entwickelungs- 
mech., Heft 11 (1911). 
* Studies on the Dynamics of Morphogenesis and Inheritance in Experimental Repro- 
duction. II. Physiological Dominance of Anterior over Posterior Regions in the Regu- 
lation of Planaria dorotocephala, J. Exp. Zool., 11 (1911). 
Studies, etc. III. The Formation of New Zooids in Planaria and other Forms, Ibid. 
^ Studies, etc. IV. Certain D3Tiamic Factors in the Regulatory Morphogenesis of Pla- 
naria dorotocephala in Relation to the Axial Gradient, Ibid., 13 (1912). 
« Studies, etc. V. The Relation between Resistance to Depressing Agents and Rate 
of Reaction in Planaria dorotocephala and its Value as a Method of Investigation, Ibid., 
14 (1913). -V^ i4'^H^-4 i 
^ Certain Dynamic Factors in Experimental Reproduction and their Significance for the 
Problems of Reproduction and Development, Arch. Entwickelungsmech., 35 (1913). 
* Studies, etc. VI. The Nature of the Axial Gradients in Planaria and their Relation 
to Antero-posterior Dominance, Polarity and Symmetry, Ibid., 37 (1913). 
^ Susceptibility Gradients in Anunals, Science, 39 (1914). 
1° The Axial Gradient in CiHate Infusoria, Biol. Bull., 24 (1914). 
