Senna hayesiana (Britton & Rose) H. S. Irwin & Barneby

Chamaefistula membranacea Britton & Rose, sp. nov
Twigs slender, sparingly pubescent when young, soon glabrous. Petiole 2-3 cm. long; rachis bearing an ovoid-conic gland between the lower pair of leaflets; leaflets membranous, oblong to elliptic, acute or acutish, 5-10 cm. long, dull and glabrous above, loosely short-pilose beneath, slightly inequilateral; inflorescence axillary, paniculate strigose; pedicels 2-4 cm. long; sepals loosely short-strigose, 5-8 mm. long; petals oblong to suborbicular, about 13 mm. long.
Vicinity of Tonacatepeque, San Salvador, El Salvador, December 30, 31, 1921, Standley 19430.

Chamaefistula hayesiana Britton & Rose, sp. nov
Twigs slender, sparingly strigillose or glabrous, nearly straight, subterete. Petiole rather stout, 1.5-2 cm, long; leaflets subchartaceous, various, sparingly appressed-pubescent, lanceolate to elliptic or obovate, acute, cuspidate or retuse; rachis bearing a cylindric-conic gland between the lower pair of leaflets and sometimes a slender one between the upper pair; inflorescence axillary and terminal, strigose, several-flowered; pedicels slender, nearly erect, 1-2.5 cm. long; sepals appressed-pubescent, 5-8 mm. long; petals oblong-elliptic, 10-11 mm. long.
Gatun, Panama, October 1859, 5. Hayes 572.

Chamaefistula valerioi Britton & Rose, sp. nov
. shrub, 3-5 m. high, the stout flexuous twigs at first short-pubescent, becoming glabrous. Petiole stout, 2-2.5 cm. long; rachis bearing an ovoid gland between the lower pair of leaflets or between both pairs; leaflets chartaceous, acute or short-acuminate, broadly ovate to elliptic, glabrous above, pilose on the veins beneath, 5-11 cm. long; inflorescence terminal, corymbosepaniculate, puberulent, many-flowered; pedicels slender, about 3 cm. long, or shorter; sepals elliptic, appressed-pubescent, 6-8 mm. long; petals orbicular-obovate, 14-15 mm. long; legume slender, 15-18 cm. long, about 8 mm. broad, sparingly strigose when young, glabrous when mature.
Costa Rica. Type from vicinity of Tilaxan, Guanacaste, January 10-31, 1926, Siandley 6f Valeria 44266. Yucatan?

Chamaefistula williamsii Britton, sp. nov
A shrub, 2.5-5 m. high, the young twigs puberulent, becoming glabrous. Petiole stout, 2-3 cm. long; rachis bearing a short ovoid or ovoid-conic gland between the lower pair of leaflets, or between both pairs; leaflets subcoriaceous, acute or short-acuminate, slightly or moderately inequilateral, 5-1 1 cm. long, dull and glabrous above, more or less pilose beneath; inflorescence densely puberulent, axillary and terminal, few -several-flowered; pedicels 2 cm. long, or shorter; sepals elliptic, strigose, 5-7 mm. long; petals elliptic-obovate, 15 mm. long; legume turgid, often torulose, glabrous, 7-15 cm. long, 10-12 mm. thick, stout-beaked.
Panama. Type from Penomene, February 23-March 22, 1908, R. S. Williams 135.

Chamaefistula standleyi Britton & Rose, sp. nov
A tree, about 6 m. high, the twigs and inflorescence short-pubescent. Stipules linear, acuminate, about 12 mm. long; rachis bearing a subconic gland between the lower pair of leaflets; leaflets broadly ovate, submembranous, inequilateral, short-acuminate or acute, glabrate above, loosely pilose beneath, those of lower leaves 10-13 cm. long; inflorescence loosely paniculate, the racemes subtended by small leaves; bracts oblong or oblong-lanceolate, 3-4 mm. long, persistent; pedicels nearly filiform, 1.5-4 cm. long; sepals oblong, sparingly pubescent, 6-7 mm. long; petals elliptic to orbicular-obovate, rounded, pale yellow, 10 mm. long.
Vicinity of San Jose, Costa Rica, December 4, 1925-February 10, 1926, Standley 41236.

Chamaefistula subpilosa Britton & Rose, sp. nov
A shrub, about 2 ra. high, the twigs glabrate. Petiole about 1.5 cm. long, or shorter, sparingly strigose; rachis bearing a subconic gland between the lower pair of leaflets; leaflets chartaceous, oblong to elliptic, acute or short-acuminate, glabrous above, pilose beneath, at least on the veins, 4-6 cm. long, or those of upper leaves smaller; inflorescence axillary and terminal, strigose, few-flowered; pedicels slender, 2-3 cm. long; sepals 5-7 mm. long, sparingly strigose; petals orbicular or broadly obovate, 15 mm. long; young legume densely strigose.
Vicinity of Ahuachupan, El Salvador, January 9-27, 1922, Standley 20022.

Chamaefistula maxonii Britton & Rose, sp. nov
A .shrub or vine, about 3 m. long, the young parts softly short-pubescent. Stipules linearfalcate; petioles 1.5-3 mm. long; glands often borne between both pairs of leaflets, slender, sometimes more than one between the upper pair; leaflets 6-10 cm. long, lanceolate to ovate, membranous, acuminate, green and slightly i>ubesccnt above, very pale and softly pubescent beneath; inflorescence axillary, 2-flowered, or paniculate and many-flowered; pedicels 2-4 cm. long, slender; sepals narrowly-oblong, 5-9 mm. long; petals yellow, somewhat pubescent on the outside, 1.5-2 cm. long; ovary lanate-pubescent; legume slender, terete, glabrate, 10-15 cm. long.
Panama. Type from Chiva-Chiva trail above Red Tank, Canal Zone, May 28, 1923, Maxon & Harvey 6611.

Chamaefistula chiapensis Britton & Rose, sp. nov
Branches stout, slightly flexuous, loosely short-pubescent when young. Stipules lanceolate, long-acuminate, 10-13 mm. long, persistent; petiole 1-2 cm. long; rachis bearing a short gland between the lower leaflets; leaflets ovate to elliptic, chartaceous, 5-13 cm. long, gradually sharply acuminate or acute, somewhat inequilateral, glabrous above, short-pilose beneath; inflorescence broadly paniculate, the racemes subtended by small leaves, rather densely strigose; bracts ovate to lanceolate, 5-8 mm. long, persistent; pedicels slender, strigose, 1.5-3 cm. long; sepals ovate to oblong, sparingly pubescent, ciliate, 6-8 mm. long; petals obovate-elliptic, pubescent, 13-17 mm. long; young legume densely yellowish-strigose.
Between Teneapa and Ajalon, Chiapas, October 13, 1895, E. W. Nelson 3289.

Chamaefistula anconis Britton & Rose, sp. nov
A shrub, about 3 m. high, the young twigs tomentulose. Petiole 2-3 cm. long ; rachis puberulent, bearing a short, ovoid gland between the lower pair of leaflets; leaflets ovate to elliptic. nearly membranous, dull, acute or short-acuminate, moderately inequilateral, glabrous above when old, rather densely short-pilose beneath, 5-9 cm. long; inflorescence axillary and forming a several-flowered subterminal panicle, densely tomentulose; pedicels about 2 cm. long, or shorter; sepals oblong-elliptic, 4—6 mm. long; petals 13-16 ram. long, elliptic-obovate; legume 7-16 cm. long, about 1 cm. thick, stout-beaked, glabrous, short-stipitate.
Ancon hill. Canal Zone, Panama. Type collected February 20, 190S, R. S. Williams 9, type, fruiting specimen; Killip 12055, October 17, 1922, flowering.

Chamaefistula lanata Britton, sp. nov
Twigs, petioles and inflorescence puberulent. Petioles 2-4 cm. long; glands short, stout, borne between one or both pairs of leaflets; leaflets ovate to oblong-elliptic, subcoriaceous, acute, 5-12 cm. long, light green, glabrous and dull above, rather densely short-pubescent beneath; panicle terminal, rather densely many-flowered, short-peduncled; pedicels about 1.5 cm. long, or shorter; sepals densely strigose, 6-8 mm. long; petals densely white-lanate without, about 18 mm. long.
Mejicanos, El Salvador, August 1, 1922, Salvador Colder Sn 1103.

Senna hayesiana là một loài thực vật có hoa trong họ Đậu. Loài này được (Britton & Rose) H.S.Irwin & Ba miêu tả khoa học đầu tiên.