Thanks Fd'AF for his interesting letter. CD suggests observations it would be worth making [in the Azores] although he is too old to make any direct use of them. Fauna and flora of different islands should be compared and the plants and animals from all high mountain summits collected. Suggests Fd'AF investigate the presence of glacial deposits and fossils on the islands. Survival of eggs in salt-water should be tested, as the wide distribution of lizards, land molluscs, and earthworms is a perplexing problem.
Will be very glad to read the essays Fd'AF sent.