Summary

Suggests an explanation for difference in excitability of Drosera leaves to meat and albumen on the one hand and, on the other, fibrin, areolar tissue, gelatin, and fibrous basis of bone.

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

Will prepare experiments with the fatty acids on digestion of gluten. Has found it is digested slowly, but entirely, with pepsin and hydrochloric acid.

Summary

Is delighted to hear that Pinguicula and Drosera digest fibrin. Suggests diluting gluten in weak hydrochloric acid to remove starch. Enamel was nearly digested [by Drosera] overnight. Would like to try separating the digestive ferment of Pinguicula.

Summary

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

Summary

Reports results of experiments comparing digestibility of gluten and fibrin for CD’s work on Drosera.

Summary

Thanks for the careful experiments, particularly on organic acids.

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

Sends CD provisional information that artificial gastric juice dissolves bone entirely and that gluten and fibrin are completely dissolved in hydrochloric, propionic, and butyric acids. [See Insectivorous plants, pp. 118–19.]

Summary

Thanks for fibrin. Drosera and Pinguicula dissolve it thoroughly.

Summary

Thanks JSBS for his work. CD concludes the ferment of Drosera must differ from pepsin.

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 the acid digestion experiments, which can be printed as they are. CD trying Drosera on dentine and enamel.

Summary

Responds to CD’s questions about relation to gelatin of areolar tissue, fibrous basis of bone, and other substances CD is using in his work on digestion of Drosera.

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

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

Has been testing the digestive powers of Drosera; wants to know whether a group of substances that elicit similar responses are related.

Summary

Reports on his examination of the effects of Drosera secretion on tooth enamel and dentine, and of artificial gastric juice on fibrous basis of bone.

Summary

Sends cartilage from cat’s ear, the elastic fibres of which will probably resist digestion [by Drosera]. Is preparing fibro-cartilage, which he expects will be digested easily. [See Insectivorous plants, p. 104.]

Summary

Describes his work on Nepenthes.

Cephalotus is a beast.

His address is a history of Dionaea, Sarracenia, and Drosera.

Thiselton-Dyer has helped enormously except with the observations; but his health is so poor that JDH thinks he is "evidently cut out for a Literate not a working botanist".