01 - VIII - Principles of Sexual Selection Part 1

02 - VIII - Principles of Sexual Selection Part 2

03 - VIII - Principles of Sexual Selection Part 3

04 - VIII - Principles of Sexual Selection Part 4

05 - VIII - Principles of Sexual Selection Part 5

06 - VIII - Principles of Sexual Selection Part 6

07 - IX - Secondary Sexual Characters in the Lower Classes of the Animal Kingdom

08 - X - Secondary Sexual Characters of Insects Part 1

09 - X - Secondary Sexual Characters of Insects Part 2

10 - XI - Insects, continued

11 - XII - Secondary Sexual Characters of Fishes, Amphibians, and Reptiles Part 1

12 - XII - Secondary Sexual Characters of Fishes, Amphibians, and Reptiles Part 2

13 - XIII - Secondary Sexual Characters of Birds Part 1

14 - XIII - Secondary Sexual Characters of Birds Part 2

15 - XIII - Secondary Sexual Characters of Birds Part 3

16 - XIV - Birds - continued Part 1

17 - XIV - Birds - continued Part 2

18 - XIV - Birds - continued Part 3

19 - XV - Birds - continued Part 1

20 - XV - Birds - continued Part 2