CHAPTER IX. 



LAWS OF TRANSMISSION BY INHERITANCE. 

 ADAPTATION AND NUTRITION. 



Distinction between Conservative and Progressive Transmission bj Inherit- 

 ance. — Laws of Conservative Transmission : Transmission of Inherited 

 Characters. — Uninterrupted or Continuous Transmission. — Interrupted 

 or Latent Transmission. — Alternation of Generations. — Relapse. — 

 Degeneracy. — Sexual Transmission. — Secondary Sexual Characters. — 

 Mixed or Amphigonous Transmission. — Hybrids. — Abridged or Simpli- 

 fied Transmission. — Laws of Progressive Inheritance : Transmission of 

 Acquired Characters. — Adapted or Acquired Transmission. — Fixed or 

 Established Transmission. — Homochronous Transmission (Identity in 

 Epoch). — nomotopic Transmission (Identity in Part) . — Adaptation and 

 Mutability. — Connection between Adaptation and Nutrition. — Distinc- 

 tion between Indirect and Direct Adaptation. 



In the last chapter we considered Transmission by Inherit- 

 ance, one of the two universal vital activities of organisms. 

 Adaptation and Inheritance, which by their interaction 

 produce the different species of organisms, and we have 

 endeavoured to trace this very mysterious vital activity to 

 a more general physiological function of organisms, namely, 

 to Propagation. This latter in its turn, like other vital 

 phenomena of animals and plants, depends on physical and 

 chemical relations. It is true they appear at times ex- 

 ceedingly complicated, but can nevertheless in reality be 

 traced to simple mechanical causes — that is, to the relations 



