CONTENTS XXV 



PAGE 



On the Effects of Selection 397 



Inheritance of Coat-color in Guinea Pigs 398 



Inheritance of Hooded Pattern in Rats 398 



Lethal Genes in Yellow Mice 399 



Inheritance of Winter Egg Production by Fowls t 400 



Inheritance in Dairy Cattle 402 



Inheritance of Speed in Horses 402 



Value of Improved Breeds 403 



Summary 403 



Section 10. Evolution 



CHAPTER XXXIV 



Evidences of Evolution 



Evolution Defined 407 



Sources of Evidence 407 



Evidences from Paleontology 408 



History of the Horse 409 



Evolution of Camels 410 



Classification 411 



The Modern System of Classification 412 



Scientific Names 413 



Comparative Anatomy 414 



Rudimentary or Vestigial Organs 414 



Evidence from Embryology 416 



Development of Vertebrates 416 



Geographical Distribution 417 



Artificial Selection 418 



Genetics 419 



CHAPTER XXXV 



Theories of Evolution 



Pre-Darwinian Science 420 



The Influence of Darwin's Work 420 



Factors of Darwin's Theory 421 



Overproduction 421 



Stationary Numbers of Individuals 422 



The Struggle for Existence • 422 



Interrelations of Organisms 423 



Variation and Heredity 423 



The Survival of the Fittest 424 



Application of the Theory 425 



Sexual Selection 425 



Lamarckism 427 



The New Lamarckian School 428 



Orthogenesis or Determinate Evolution 429 



