Hopes CD will read and comment on his lecture ["Origin of flora of the Alps", Proc. R. Geogr. Soc. (1879)]. Disgrees with CD; JB maintains that the high antiquity of existing plant genera and families explains wide differences in their distribution.

Thanks CD for noticing some difficulties in his hypothesis. Concedes that there is no proof that higher plants are more intolerant of carbon dioxide than lower plants. Argues that the main difference between the lowlands and the high mountains in Palaeozoic times would be the much greater climatic fluctuations that would occur on the mountains. Discusses carbon dioxide diffusion in the Palaeozoic atmosphere. Thinks that the large number of species and genera peculiar to high mountains favours the assumption that "their diffusion must date from a geologically remote period" [see ML 2: 20–2].

Expands on a letter to Nature concerning the probability of the survival of a new variety in a given species. Differs with [F. Jenkin’s] argument, to which CD had agreed to a greater extent than JB feels it deserved.

Received CD’s note late and so could not comply, but promises to vote in future for anyone CD recommends for Athenaeum.

Will have new evidence on dog’s intelligence sent to CD.