XIV CONTENTS. 



CHAPTER XVIII. 



OF GENERATION. 



PAGE 



1. General Character of the Function, 879 



2. Action of the Male, .... 882 



Structure of Testes. Spermatic Fluid, 884 



Coitus; Emissio Seminis, ......... 885 



3. Action of the Female, 889 



Structure of Ovary, Ovisac, and Ovum, 889 



Puberty; Menstruation, ......... 892 



Maturation of Ova ; Corpus Luteum, ...... 896 



Fecundation of Ovum, ......... 899 



Formation of Decidua, ......... 902 



Formation of Placenta, ......... 904 



Parturition; Duration of Gestation, ....... 909 



4. Development of the Embryo, ......... 921 



5. Of Lactation, 970 







CHAPTER XIX. 



OF THE DIFFERENT BRANCHES OF THE HUMAN FAMILY, AND THEIR MUTUAL 



RELATIONS. 



1. General Considerations ; Diiferentiation of Species, ..... 982 



2. General Survey of the Principal Varieties of the Human Species, . . 1000 



CHAPTER XX. 



OF THE MODES OF VITAL ACTIVITY CHARACTERISTIC OF DIFFERENT AGES. 



1. General Considerations ; Germinal Capacity, ...... 1014 



2. Period of Growth and Development 1017 



3. Period of Maturity, 1028 



4. Period of Decline, . . . ... 1029 



CHAPTER XXI. 



OF DEATH, 1031 



