Other varieties are _Zifiri_, _Hamouli_ and _Gallini_, all of minor importance.
2. _G. brasiliense_, Macf. (_G. peruvianum_, Engler), or kidney cotton. Amongst the varieties of cotton which are derived from this species appear to be Pernambuco, Maranham, Ceara, Aracaty and Maceio cottons. The fibre is generally white, somewhat harsh and wiry, and especially adapted for mixing with wool. The staple varies in length from 1 to about 1½ in.
3. _G. hirsutum_, Linn. Although _G. barbadense_ yields the most valuable cotton, _G. hirsutum_ is the most important cotton-yielding plant, being the source of American cotton, i.e. Upland, Georgia, New Orleans and Texas varieties. The staple varies usually in length between ¾ and 1¼ in. According to Watt there are many hybrids in American cottons between _G. hirsutum_ and _G. mexicanum_.
4. _G. herbaceum_, Linn. Levant cotton is derived from this species. The majority of the races of cotton cultivated in India are often referred to this species, which is closely allied to _G. hirsutum_ and has been regarded as identical with it. Amongst the cottons of this source are Hinganghat, Tinnevelly, Dharwar, Broach, Amraoti (Oomras or Oomrawattee), Kumta, Westerns, Dholera, Verawal, Bengals, Sind and Bhaunagar. Watt dissents from this view and classes these Indian cottons as _G. obtusifolium_ and _G. Nanking_ with their varieties. The Indian cottons are usually of short staple (about ¾ in.), but are probably capable of improvement.
5. _G. arboreum_, Linn. This species is often considered as indigenous to India, but Dr Engler has pointed out that it is found wild in Upper Guinea, Abyssinia, Senegal, etc. It is the "tree cotton" of India and Africa, being typically a large shrub or small tree. The fibre is fine and silky, of about an inch in length. In India it is known as Nurma or Deo cotton, and is usually stated to be employed for making thread for the turbans of the priests. Commercially it is of comparatively minor importance.
The following table, summarized from the _Handbook to the Imperial Institute Cotton Exhibition_, 1905, giving the length of staple and value on one date (January 16, 1905), will serve to indicate the _comparative_ values of some of the principal commercial cottons. The actual value, of course, fluctuates greatly.