CONTENTS 
CHAPTER VIII 
MENDELISM (continued) 
Coupling : complete and partial—Reversion on crossing : 
The 
Sir 
The 
masked characters—Examples in peas, mice, and 
sweet-peas—Various Mendelian characters—Doubt- 
ful cases; normal fertilization The supposed 
‘ swamping ’ of new species on crossing with the old— 
Summary of Mendelian ideas-— Mendelism and 
biometry : researches of Yule and Pearson—Practical 
applications : Biffen’s work with cereals ; ‘ strength ’ 
of wheat-flour and rust-immunity - - - 
CHAPTER IX 
RECENT CYTOLOGY 
cell—Cell-division and cell-fusion—The nucleus— 
Nuclear division — The nature and properties of 
chromosomes—The reducing division—The study of 
the chromosomes in the light of Mendel’s discovery— 
Chromomeres — The heredity of sex— The germ- 
plasm theory - - - - 
CHAPTER X 
EUGENICS 
Francis Galton, pioneer—Genetics and biometry— 
Effect of civilization and humanitarianism—Twins— 
Hereditary nature more important than training— 
Consequent legislation—Restraint of propagation— 
Graduation of incomes—Karl Pearson—Eugenics 
Education Society - - - 
CHAPTER XI 
CONCLUDING CHAPTER 
science of genetics—Mendel’s law—The #-generation 
and the 2#-generation—Discontinuous variation— 
The mutation theory—Continuous variations—Gene- 
tic variations and acquired variations—Johannsen’s 
theory of the pure line—The modern view of the 
method of origin of new species—The science of 
genetics applied to human affairs—George Bernard 
Shaw’s view of the situation - - - - 
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