[5] Socially, morally, and religiously.
[6] Lyell.
[7] Readers not familiar with Elementary Zoölogy will do well to consult the Classification of Animals in [Section VII.]; and also the [Diagram of Development].
[8] Wallace.
[9] Belt.
[10] Wallace.
[11] Wallace.
[12] Wallace.
[13] Darwin.
[14] Darwin.