Down, | Beckenham, Kent.
Oct 9. 74
My dear Dr Sanderson
I am going to beg your opinion & information on one point if you can give it. I am finally working up my long chapter on digestion by Drosera.1 I find that fibrin, areolar tissue, the fibrous basis of bone, & gelatin all agree in being easily dissolved by the secretion, but none of them excite the leaves much, incomparably less than meat, albumen, &c. Fibro-cartilage behaves in the same way excepting that it is never thoroughly liquified.2 Now what I want to know is whether these substances viz:— fibrin, areolar tissue, the fibrous basis of bone, gelatin, & fibro-cartilage are chemically or physiologically allied. I mean by physiologically allied, their action on animals to which they are given as food; for instance is it known whether a dog would perish as soon when fed on fibrin as on gelatin? I should be grateful for any scrap of information on this head. You will see that I speak of the “fibrous basis of bone”, is this a correct expression? In almost every page of my MS I feel how much I owe to you
Yours very sincerely | Ch. Darwin
Please cite as “DCP-LETT-9669,” in Ɛpsilon: The Charles Darwin Collection accessed on