Charles Darwin books in order
10 books in the catalogue, about 82 hours of reading in all; the shortest takes 3 hours and the longest 13 hours.
10 standalone books in the catalogue.
Standalone books
Charles Darwin's The Voyage of the Beagle: 9.3 h 
On the Origin of Species by Means of Natural Selection 9.2 h 
The Variation of Animals and Plants Under Domestication 8.1 h 
The Descent of Man, and Selection in Relation to Sex 12.6 h 
The Descent of Man 12.9 h 
The Expression of Emotions in Man and Animals 6.8 h 
Insectivorous Plants 7.7 h 
The Life and Letters of Charles Darwin 10.5 h 
The Autobiography of Charles Darwin 2.6 h 
The Origin of Species 2.7 h