L. H. Palm [Über das Winden der Pflanzen (1827)] is better on climbing plants than H. von Mohl [Über den Bau und das Winden der Ranken und Schlingpflanzen (1827)].

If CD understood Nepenthes, he would understand every class of climbers.

Thanks for correcting Fritz Miller’s paper on climbing plants. CD will send it to Linnean Society.

Requests addresses of J. E. Planchon, W. F. Hofmeister and M. J. Schleiden so he can send them copies of Lythrum paper [Collected papers 2: 106–31].

Sends Fritz Müller’s paper ["Notes on some of the climbing plants near Desterro, in S. Brazil", J. Proc. Linn. Soc. Lond. (Bot.) 9 (1867): 344–9] to be refereed.

Is it now thought that the spongioles of rootlets secrete carbonic acid which acts on bones and rocks?

CD will publish on Primula [Collected papers 2: 45–63]. Will DO ask W. H. Fitch to make woodcuts of "pin" and "non-pin" primroses [i.e., long-styled and short-styled forms]? Encloses a sketch.

Discusses the cleistogamous flowers of Oxalis. Thinks they may not be truly cleistogamous but merely arrested or imperfectly developed normal flowers.

Thanks for Forms of flowers.

Alexander Dickson would like to know whether anyone has described the epidermal cells lining the pitcher of Cephalotus.

Extracts from botanical literature dealing with Dionaea, intercrossing, and sensitivity. [Bot. Ztg. (1833): 96; Thomas Nuttall, Genera of N. American plants (1818)].

Cites descriptions of melastomads in C. V. Naudin, Annales des Sciences Naturelles 3d ser., vols. 12–18.

CD’s observations on preference of Drosera for milk and nitrogenous fluids, and the effect of nitrate of ammonia are interesting. Asks whether CD is satisfied that the effect is not due to density of fluid or to a chemical irritant. His own observations suggest such possibilities.

His results with pure gum on Drosera spathulata entirely support CD’s opinion. Other observations on insectivorous plants.

Quotes note by Julius Milde on Drosera rotundifolia from Botanische Zeitung (1852): 540.

Dr Hooker has given him CD’s memorandum on the fly-catcher.

Copies out extract from Curtis’ Botanical Magazine [On Apocynum androsæmifolium, 8 (1794): tab.]: 280 and gives a further reference in Erasmus Darwin’s The loves of plants [1789]. Suggests that they look at Apocynum.

List of references on orchid structure and fertilisation.

Refers CD to a paper which he ought to know: Ch. Fermond, "Faits pour servir à l’histoire générale de la fécondation chez les végétaux", Recueil des travaux de la Société d’émulation pour les sciences pharmaceutiques 3 (1859).

Now believes flowers of Fumariaceae must be self-fertilised.

Planning a piece on dimorphism in the Natural History Review ["On the two forms, or dimorphic condition, in the species of Primula … by Charles Darwin", n.s. 2 (1862): 235–43].

Observations on Campanula dimorphism.

Distinguishes two kinds of floral dimorphism: that affecting sexual organs and that affecting outer envelopes.

Thanks for Orchids.