Welcomes ARW’s paper on pigeons ["On the pigeons of the Malay Archipelago", Ibis 1 (1865): 365–400].

Influence of monkeys on distribution of pigeons and parrots.

Asks ARW to explain a passage in his paper on Malayan Papilionidae [Trans. Linn. Soc. Lond. 25 (1866): 1–71] on how dimorphic forms are produced. CD knows of varieties "that will not blend or intermix", but which produce offspring quite like either parent.

ARW’s remarks on geographical distribution in Celebes "will give a cold shudder to the immutable naturalists".

Presses ARW to work on his travel journal.