Chapter 17
1. The Story of Our Continent, Shaler.
2. Elements of Geology, Blackwelder and Barrows.
3. The Story of Evolution, McCabe.
4. Encyclopedia Britannica, article, _Geology_ (palæontological and physiographical).
1. The Story of Our Continent, Shaler.
2. Elements of Geology, Blackwelder and Barrows.
3. The Story of Evolution, McCabe.
4. Encyclopedia Britannica, article, _Geology_ (palæontological and physiographical).