資料來源:http://tw.myblog.yahoo.com/jw!tW1hha.LQUOoYnkrpKA-/article?mid=2082
D.
棉屬4 

1. Gossypium herbaceum  Linn. 草棉〔(拉)gossypion棉花〕

(1)一年生草本或亞灌木。

(2)葉掌狀5裂,寬>長。

(3)花黃色,副萼頂端有6~8齒。

(4)蒴果卵圓形,長3㎝,先端具喙。

(5)棉花是種子表面的毛,長可達1065cm

(6)原產阿拉伯及小亞細亞。

2. Gossypium arboreum L. 樹棉 

(1)大灌木,多年生,高可達3m

(2)葉掌狀5深裂。

(3)花冠黃白色,徑約10cm

(4)蒴果頂端漸窄,常下垂,長3㎝。

(5)種子混生白色長纖毛,和不易剝落之短纖毛。

(6)原產印度。

3. Gossypium hirsutum Linn. 陸地棉 

(1)一年生草本,高1.5m,小枝疏被長毛。

(2)葉闊卵形,基部心形,常3淺裂。

(3)原產墨西哥,現已取代草棉、樹棉,廣為栽培。

4. Gossypium barbadense Linn. 海島棉 

(1)多年生亞灌木或灌木,高2-3m

(2)小枝暗紫色,具稜角,光滑無毛。 

(3)掌狀3~5深裂,基部心形。

(4)蒴果橢圓狀卵形,長3~5㎝。 

(5)原產南美熱帶及西印度群島。

http://www.efloras.org/florataxon.aspx?flora_id=3&taxon_id=113948 棉屬
http://www.efloras.org/florataxon.aspx?flora_id=3&taxon_id=200013694    草棉
http://www.efloras.org/florataxon.aspx?flora_id=3&taxon_id=200013690  樹棉
http://www.efloras.org/florataxon.aspx?flora_id=3&taxon_id=200013692  海島棉
http://www.efloras.org/florataxon.aspx?flora_id=3&taxon_id=200013695  陸地棉

Description from Flora of China
樹棉 Gossypium arboreum Linn.
Subshrubs or shrubs, perennial, 2-3 m tall. Young branchlets villous. Stipules filiform, caducous; petiole 2-4 cm, puberulent and villous; leaf blade 3-5-lobed, 4-8 cm in diam., lobes oblong-lanceolate, oblong, ovate, or obovate, ca. 1/2 as long as leaf blade, abaxially stellate puberulent, villous along veins, adaxially stellate pilose. Flowers solitary, axillary. Pedicel 1.5-2.5 cm, villous. Epicalyx lobes 3, connate for basal 1/3, ovate-cordate or triangular, ca. 2.5 cm, stellate villous on veins, 3- or 4-toothed, teeth less than 3 × as long as wide. Calyx shallowly cup-shaped, nearly truncate. Corolla yellowish, often dark purple in center, campanulate; petals 3-5 cm. Staminal column 1.5-2 cm; filaments uniform in length. Capsule 3(or 4 or 5)-loculed, cone-shaped, usually pendulous, ca. 3 cm, glabrous, with numerous oily and glandular minute spots, apex tapering, beaked. Seeds 5-8 per cell, free, ovoid, 5-8 mm in diam., with white wool and moderately persistent short fuzz. Fl. Jun-Sep.

Cultivated. Guangdong, Guangxi, Sichuan, Taiwan, Yunnan [cultivated in tropical and subtropical regions of the Old World; origin in India and Sri Lanka].

草棉 Gossypium herbaceum Linn.
Herbs or subshrubs, annual, to 1.5 m tall, pilose. Stipules filiform, 5-10 mm, caducous; petiole 2.5-8 cm, villous; leaf blade usually 5-lobed, 5-10 cm in diam., usually wider than long, lobes broadly ovate, less than 1/2 as long as leaf blade, abaxially minutely puberulent and villous on veins, adaxially stellate hirsute, base cordate, apex acute. Flowers solitary, axillary. Pedicel 1-2 cm, villous. Epicalyx lobes connate at base, broadly triangular, 2-3 cm, wider than long, sparsely villous on veins, 6-8-toothed. Calyx cup-shaped, 5-lobed. Corolla yellow, purple in center, 5-7 cm in diam.; petals 2.5-3 × 3-4 cm. Filaments uniform in length. Capsule usually 3-4-celled, ovoid, ca. 3 cm, apex beaked. Seeds free, obliquely cone-shaped, ca. 10 mm, with white wool and persistent short fuzz. Fl. Jul-Sep.

Among the races recognized by Hutchinson (Emp. Cotton Gr. Rev. 27: 12. 1950) is "kuljianum," which is found in "Chinese Central Asia."

Cultivated. Gansu, Guangdong, Sichuan, Xinjiang, Yunnan [cultivated in India; origin in SW Asia].

海島棉 Gossypium barbadense Linn.

Subshrubs or shrubs, perennial, 2-3 m tall, hairy or only hairy on petiole and veins on abaxial surface. Branchlets dark purple, angular. Stipules lanceolate-falcate, ca. 10 mm, usually caducous; petiole longer than leaf blade, with black glandular spots; leaf blade 3-5-lobed, 7-12 cm in diam., lobes ovate, oblong, oblong-lanceolate, or obovate, more than 1/2 as long as blade, central lobe longer, lateral lobes usually extending, base cordate, apex long acuminate. Flowers terminal or axillary. Pedicel usually shorter than petiole, stellate villous, with black glandular spots. Epicalyx lobes 5 or more, free, broadly ovate, 3.5-5 cm, base rounded-cordate, 10-15-toothed, teeth 3-4 × as long as wide. Calyx cup-shaped, truncate, with black glandular spots. Corolla pale yellow, purple or crimson in center, funnelform; petals 5-8 cm, stellate villous abaxially. Staminal column 3.5-4 cm, glabrous; filaments closely appressed, upper ones longer. Capsule 3(or 4)-celled, oblong to oblong-ovoid, 3-7 cm, with obvious glandular spots abaxially, base larger, apex acute to beaked. Seeds black and smooth when hair fallen, free or aggregated, ovoid, ca. 8 mm, beaked, with white wool and easily detached short fuzz on one or both tips. Fl. summer-autumn.

Cultivated; below 1500 m. Guangdong, Guangxi, Hainan, Yunnan [India; Africa (Egypt), tropical Asia, North America (United States), Pacific islands, tropical South America].

陸地棉 Gossypium hirsutum Linn.

Gossypium hirsutum
f. mexicanum (Todaro) Roberty; G. mexicanum Todaro; G. religiosum Linnaeus.

Herbs, annual, 0.6-1.5 m tall. Branchlets sparsely villous. Stipules ovate-falcate, 5-8 mm, caducous; petiole 3-14 cm, pilose; leaf blade broadly ovate, 3(-5)-lobed, 5-12 cm in diam., lobes broadly triangular to ovate-orbicular, base broad, central lobe usually 1/2 as long as leaf blade, abaxially sparsely villous, adaxially nearly glabrous, scabrously hairy on veins, base cordate or cordate-truncate, apex acuminate. Flowers solitary, axillary. Pedicel usually slightly shorter than petiole. Epicalyx lobes 3, free, to 4 × 2.5 cm (including teeth), hirsute and ciliate with long hairs, base cordate, with 1 gland, 7-9-toothed near apex, teeth 3 or 4 × as long as wide. Calyx cup-shaped, 5-lobed, lobes triangular, ciliate. Corolla white or yellowish, fading to reddish or purple, funnelform; petals 4-5.5 × 3.5-4.5 cm. Staminal column 1-2 cm; filaments lax, upper ones longer. Capsule 3- or 4-celled, ovoid, 3.5-5 cm, apex beaked. Seeds free, ovoid, with white wool and gray-white moderately persistent short fuzz. Fl. summer-autumn.

Gossypium hirsutum has replaced G. arboreum and G. herbaceum in the cotton-producing areas of China.

Widely cultivated in China [probably of American origin (?Mexico), now cultivated throughout warmer parts of the world].