Summary

Requests that DO examine enclosed microscope slides of Acropera ovules, to confirm CD’s opinion that females are non-functional.

Can DO comment on disagreement between Robert Brown and John Lindley over the number of Acropera carpels?

O. Heer’s Atlantis theory vs CD’s hypothesis of a migration north during warm periods.

Summary

Glad CD has given up on Acropera ovules.

Doubts phanerogams less different in extreme forms [than Crustacea].

No systematic parallelism between plants and animals.

Offers list of Arctic plants with their colours. Asks CD whether it is useful to add colour to [descriptions of] plants.

Summary

Argument, based on geographical distribution and competition, for a mundane glacial period rather than cooling of one longitudinal belt at a time.

Summary

Sends some replies to CD’s queries and data on pigeon flights between Bordeaux and Verviers.

Summary

Since his previous letter, has unexpectedly arranged to go to London next Tuesday.

Hopes to call on recipient.

Summary

JDH’s letter on grounds of generalisation in plant morphology.

Faunal distribution and the glacial period.

Orchid homologies.

Summary

Thanks TD for his letter. Difficulties with CD’s theory are many and great, but CD thinks the reason is that we underestimate our ignorance. The imperfection of the geological record counts heavily for CD. His greatest trouble is weighing "the direct effects … of changed conditions of life without any selection, with the action of selection on mere accidental (so to speak) variability. I oscillate much on this head, but generally return to my belief that the direct [effects] … have not been great."

Is surprised that any one, like W. B. Carpenter, can go as far as to believe all birds may have descended from one parent, but will not go further and include all the members of the same great division. Such beliefs make "Divine mockeries" of morphology and embryology, the most important of all subjects.