Chapter 9.1-9.8

Chapter Ⅸ: Hybridism
9.1 ---- 00:00
9.2 Degrees Of Sterility ---- 02:38
9.3 Laws Governing The Sterility Of First Crosses And Of Hybrids ---- 20:52
9.4 Origin And Causes Of The Sterility Of First Crosses And Of Hybrids ---- 39:37
9.5 Reciprocal Dimorphism And Trimorphism ---- 57:51
9.6 Fertility Of Varieties When Crossed, And Of Their Mongrel Offspring, Not Universal ---- 68:43
9.7 Hybrids And Mongrels Compared, Independently Of Their Fertility ---- 80:40
9.8 Summary Of Chapter ---- 89:36