XVll CONTENTS 
The soma and germ plasm—experimental investigations . 
The isolation of the germ plasm : 
The inadequacy of affirmative evidence . 
The transmission of functional modifications . 
Parallel induction : 
The adequacy of other factors 
The conclusion . ae 
CHAPTER XXXI 
THE SELECTION PROBLEM IN ANIMAL BREEDING 
Introductory . ; : 
General views of calbaatine : : 
The American standard bred horse . 
Fecundity in fowls . 
Bantam fowls . ; 
Selection and breeding methods 
Selection indices . 
CHAPTER XXXII 
HYBRIDIZATION IN ANIMAL BREEDING 
Introductory. , 
Growing frig Raven & fe ericieerion : eee reece a ae 
Grading. .. . By bean te dee) BOL S Fo Geko an Deen Ole 
Crossbreeding ... . aire iden earner Heche 
Species hybridization among domestic aramele Z 
CHAPTER XXXIII1 
Disbasp AND RELATED PHENOMENA IN ANIMAL BREEDING 
Introductory. : 
The inheritance of disease ; : 
The inheritance of predisposition to disease 
The inheritance of defects . 
Defects in domestic animals . 
Immunity: toidisease 2 22 sesesn Bot ee fee ee eee 
Breeding for immunity . Pee cee ee et, Coe ck Got eG wae Ce 
CHAPTER XXXIV 
Sex 1n ANIMALS 
Introductory . : 
The determination he sex 
Sex-determination in mammals . 
Sex-determination in birds . 
The sex-ratio 
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