CONTENTS. 



INTRODUCTION. 



THE PROBLEMS OF HEREDITY AND THEIR SOLUTION, pp. 1 39. 



Preliminary statement of Mendel's principles, 8. Re- 

 lation of Mendel's discovery to the law of Ancestral 

 Heredity, 19. Heterozygote and Homozygole, 23. New 

 conceptions necessitated by Mendel's discovery, 26. Simple 

 alternative characters, or allelomorphs, 27. Compound 

 allelomorphs and their components, 29. Analytical Varia- 

 tions, 29. Relation of Mendel's principle to continuous 

 variation, 32. Dominance, 32. Non-Mendelian pheno- 

 mena, 33. False hybrids of Millardet, 34. Brief historical 

 notice, 36. 



MENDEL'S EXPERIMENTS IN PLANT HYBRIDISATION, 



pp. 4095. 



Introductory Remarks, 40. Selection of Experimental 

 Plants, 42. Division and Arrangement of Experiments, 44. 

 Characters selected, 45. Number of first crosses, 47. 

 Possible sources of error, 47. Forms of the Hybrids, 49. 

 Dominant and recessive, 49. 



First generation bred from the Hybrids, 51. Numbers 

 of each form in offspring, 52. Second generation bred from 

 the Hybrids, 55. Subsequent generations bred from the 

 Hybrids, 57. 



Offspring of Hybrids in which several differentiating 

 characters are associated, 59. The reproductive cells of 

 the Hybrids, 66. Statement of Mendel's essential deduc- 

 tions, 67. Experiments to determine constitution of germ- 

 cells, 68. Statement of purity of germ-cells, 72. 



Experiments with Phaseolus, 76. Compound characters, 

 80. Concluding Remarks, 84. 



MENDEL'S EXPERIMENTS WITH HIERACIUM, 96103. 



