Proc. Lit. and Phil. Soc. Manchester 13:62-64 (Jan. 13, 1874)
Memorandum on Brown-stapled Cotton
Major Richard Trevor Clarke
Communicated by Dr. E. Schunck, F.R.S.
The nankeen colour in cotton staple may be considered, I think, as a normal variational state, rarely met with in the present day, but very probably natural to the wild forms now nearly extinct and very imperfectly known. The two plants which have the best claim to be considered wild species that I have met with, namely, the Polynesian plant of Nuttall, and the Santo Paulo one of Mr. Aubertin, have both of them yellow cotton. The coloured state however is common to several cottons, probably to all. We find it in the hill cotton of Assam and in samples from China (Ning-Po), both Goss. herbaeeum proper, and I am told it is not unfrequently found in the fields of this species in India and elsewhere.
In India however the sort actually in cultivation is the yellow form of G. hirsutism (Orleans), and my samples from Malta are of the same kind. The only use that I know of for this staple is to make the cotton blanket clothing of the Afghans, and I think also the Kabyles use it for the same purpose.
It seems to be an object of regard, and even veneration, amongst the aborigines of various countries. In Peru the country people weave a striped cloth, white and yellow, from it, and the bodies of their ancient princes the Incas were found to have been buried enveloped in the rich brown wool of a coloured form of the large native plant.
The paler brown staple alluded to as coming from Africa is the produce of a coarse kind of Egyptian, and is of stronger quality than most. The curious kidney cotton also assumes this appearance, as I have samples of it from Parahyba del Norte, and have raised plants from its seeds. In all cases the staple suffers an unfavourable change when assuming this state, and is invariably more or less weak and short.
The occurence of the yellow state in so many different kinds will go far to account for the diversity in quality alluded to.
A tendency to brown coloration seems peculiar to the genus; it shows itself in the dark hue of the expressed oil, and when injury to the seed and capsule, by insects or otherwise, has occurred, the extravasation has resulted in stains upon the, properly, white fibre.
In the green seed capsule will be found two distinct series of colorific glands; one yellow, soluble in alcohol, the other purple, soluble in water; the brown is probably made up of these two.