“Let us now look to the mutual affinities of extinct and living species. They all fall into one grand natural system; and this is at once explained on the principle of descent” (p. 329).
Putting the three preceding passages together, we naturally inferred that “the theory of natural selection” and “the principle of descent” were the same things. We knew Mr. Darwin claimed the first, and therefore unhesitatingly gave him the second at the same time.
Again:—
“Let us see how far these several facts and inferences accord with the theory of descent with modification” (p. 331)
Again:—
“Thus, on the theory of descent with modification, the main facts with regard to the mutual affinities of the extinct forms of life to each other and to living forms, seem to me explained in a satisfactory manner. And they are wholly inexplicable on any other view” (p. 333).
The words “seem to me” involve a claim in the absence of so much as a hint in any part of the book concerning indebtedness to earlier writers.
Again:—
“On the theory of descent, the full meaning of the fossil remains,” &c. (p. 336).
In the following paragraph we read:—