288 ELEMENTS OF BIOLOGY 



diflferentiative and growth metabolism, that is, in terms of mech- 

 anism rather than vitahsm. They are visible evidences of aberrant 

 physico-chemical events that have interfered with the controlling 

 and correlating properties of leading elements or have divided 

 regions before the inherent developmental potentials have been 

 realized. In no sense do such abnormalities of form represent pun- 

 ishments or mental impressions of the parent; nor are they "freaks," 

 for they are the consequence of the operation of mechanistic prin- 

 ciples and not of supernatural laws. 



Suggested Readings 



Child, C. M.: Individuality in Organisms. University of Chicago Press, 

 1915. 



Gager, C. S.: Fundamentals of Botany. Part 3. P. Blakiston's Son and 

 Company, 19 16. 



Woodruff, L. L.: Foundations of Biology. The Macmillan Company, 

 1930. 



Richards, A,: Outline of Comparative Embryology. John Wiley and 

 Sons, 1931. 



McMurrich, J. P.: The Development of the Human Body. P. Blakiston's 

 Son and Company, 1914. 



Wieman, H. L.: An Introduction to Vertebrate Embryology. McGraw- 

 Hill Book Company, 1930. 



Loeb, J.: Artificial Parthenogenesis and Fertilization. University of Chi- 

 cago Press, 1913. 



Newman, H. H.: The Physiology of Twinning. University of Chicago 

 Press, 1923. 



