Summary

Pleased JSBS has decided to work on Drosera; sends plants. Does not know whether thermo-electric pile could detect temperature change when leaves close.

CD’s experiment with very weak hydrochloric acid repeated with success: the plants digest albumen more quickly.

Summary

FD has asked J. B. Sanderson about Mucin.

Summary

Hears from Frank [Darwin] that Drosera behaves perversely. Suggests that motor influence may move longitudinally away from the excited glands.

Summary

Answers CD’s questions of 25 July [8987] about temperatures at which cold-blooded animals are killed.

Doubts heat rigor was induced in Drosera. Gives his view of the relation of excitability to increase in temperature.

Suggests experiment to show that electrical changes in plant are the same as in animal muscle and nerve [see Insectivorous plants, p. 318].

Summary

Purpose of experiments was to determine digestive activity of liquids containing pepsin. Gives required amounts of hydrochloric, propionic, butyric and valerianic acids. Describes experiment and gives results. Also experimented on digestive activity of butyric acid at greater temperatures than the termperature of the body.

Summary

A hasty answer to CD’s letter [8987] of 25 July. Mentions Dr Osler’s observations on behaviour of colourless blood corpuscles in solutions of sodium and potassium salts of same strength.

Summary

Would welcome JSBS visit to discuss Drosera. Nitrogenous fluids can act as ferments only if they act merely by exciting molecular movement in adjoining molecules.

Glass and cotton excite movement and cause cell contents to change visibly. Huxley coming to see this phenomenon.

Studied effect of poisons 12 or 15 years ago to see whether the action was similar to that on nervous tissue.

Summary

Discusses the powers of digestion of Drosera and why certain substances produce less excitement in the plant than others.

Summary

Thanks for Indian [Medical] Gazette. Comments on article.

Summary

Sends results of experiments on digestion. Encloses two sets of notes: "Experiments on the digestibility of certain preparations sent by Mr Darwin" and "Note for Mr Darwin" [marked by CD for insertion in ch. 6 of Insectivorous plants].

Summary

"It is grand about Nepenthes."

JDH is welcome to notice in any way any of CD’s published or unpublished results with insectivorous plants. Gives an abstract of his observations on Drosera.

Summary

Thanks for MS which he intends to read while on a week’s holiday.

Sends thanks for Francis Darwin’s offer of help and says that Francis’s experiments on digestion are complete.

Summary

CD can provide leaves of Dionaea if JSBS wishes to investigate electric currents in them.

His experiments show that the digestive action of Drosera seems like that of true digestion.

Summary

Thinks it would be worth while testing for electrical changes in the leaves of insectivorous plants.

Summary

Sends his MS on Dionaea and hopes it may be useful for JSBS’s lecture ["On the mechanism of the leaf of Dionaea muscipula", Not. Proc. R. Inst. G. B. 7 (1874): 332–5].

Summary

Sends the very little globulin and haemoglobin he has to be tested with artificial gastric juice. He could get more from Samuel William Moore. Perhaps T. L. Brunton knows about the digestion of chlorophyll by animals.

Summary

Thanks for the careful experiments, particularly on organic acids.

Summary

Discusses digestion by insectivorous plants, asks JSBS to try same experiments using pepsin as the digestive agent to see how the results compare with CD’s observations on digestive power of Drosera.

Summary

Thanks for JSBS’s essays; wishes he had said something on Lister’s observations. Speculates on the fungoid nature of smallpox and why there is seldom re-infection.

Discusses digestion by Drosera, the action of its secretion being the same as that of gastric juice.

Summary

Reports that S. W. Moore may be able to provide various substances for CD’s research on the digestive power of Drosera (sundew).