Update to Charles Darwin's unpublished tree sketches

This blog has previously reproduced some of the unpublished sketches by Charles Darwin that involve tree-like relationships:

• Part 1 — collected notebooks and notes
• Part 2 — a letter to Charles Lyell
• Part 3 — a reconstruction from one of his books

Recently, the first two of these posts have been updated.

Part 1 was updated to include three new sketches. I had previously encountered references to them but had not located them amongst the online Darwin documentation.

Part 2 was updated to include information from a paper on the same topic that was published several months after the blog post itself.