THE RECONSTITUTION OF ISOLATED PIECES 121 



made progressively younger physiologically in each successive 

 generation, until further reconstitution becomes impossible. 



REFERENCES 

 CHILD, C. M. 



19110. "A Study of Senescence and Rejuvenescence Based on Experi- 

 ments with Planarians," Arch. f. Entwickelungsmech., XXXI. 



19116. "Experimental Control of Morphogenesis in the Regulation of 

 Planar ia" Biol. Bull., XX. 



ignc. "Studies on the Dynamics of Morphogenesis and Inheritance in 

 Experimental Reproduction: I, The Axial Gradient in Planaria 

 dorotocephala as a Limiting Factor in Regulation," Jour, of Exp. 

 Zool., X. 



19120. "The Process of Reproduction in Organisms," Biol. Bull., XXIII. 



19126. "Studies on the Dynamics, etc.: IV, Certain Dynamic Factors in 

 the Regulatory Morphogenesis of Planaria dorotocephala in Rela- 

 tion to the Axial Gradient," Jour, of Exp. Zool., XIII. 



1913. "Certain Dynamic Factors in Experimental Reproduction and 

 Their Significance for the Problems of Reproduction and Develop- 

 ment," Arch. f. Entwickelungsmech., XXXV. 



19140. "Studies on the Dynamics, etc.: VII, The Stimulation of Pieces 

 by Section in Planaria dorotocephala" Jour, of Exp. Zool., XVI. 



19146. "Studies on the Dynamics, etc.: VIII, Dynamic Factors in Head- 

 Determination in Planaria" Jour, of Exp. Zool., XVII. 



