LEGUMINOS A. SILVA OF NORTH AMERICA. 131 
PITHECOLOBIUM. 
FLoweErs perfect or rarely polygamous, in globose heads or in oblong or cylindrical 
spikes; calyx campanulate or tubular, 5 or occasionally 6-toothed, the teeth valvate in 
estivation ; petals as many as the teeth of the calyx, valvate in estivation; stamens 
indefinite, united into a tube at the base; ovary many-ovuled. Legume 2-valved, the 
valves after opening variously contorted, or rarely indehiscent or articulate. Leaves 
bipinnate, usually glandular. 
Pithecolobium, Martius, Cat. Hort. Monac. 188; Herb. Cathormion, Hasskarl, Retzia, i. 231. 
il. Brasil. 114. — Meisner, Gen. pt. ii. 353. — Bentham 
& Hooker, Gen. i. 597. — Baillon, Hist. Pl. ii. 70. 
Trees or shrubs, with slender branches unarmed or armed with spinescent stipules or axillary spines. 
Leaves alternate, petiolate, bipinnate; pinne many-foliolate with small leaflets, or few-foliolate with 
ample leaflets, or rarely three, two, or one-jugate, or unifoliolate ; rachis generally marked by numerous 
glands between the pinne, and between the leaflets; stipules minute or inconspicuous, sometimes 
persistent, rigid or spinescent ; leaflets usually penni-veined, occasionally many-nerved. Flowers perfect 
or sometimes polygamous, generally white, small or seldom large, produced from the axils of minute 
bractlets in pedunculate globose heads or in oblong cylindrical spikes. Peduncles from the axils of small 
deciduous bracts, solitary, fascicled or superposed, axillary or racemose or panicled at the end of the 
branches. Calyx campanulate or tubular, short-toothed. Corolla tubular or funnel-shaped, the petals 
united for more than half their length, hypogynous. Stamens many or indefinite, exserted, short or 
elongated, white or rose-color ; filaments filiform, united at the base into a tube free from the corolla 
and almost as long; anthers minute, attached on the back, versatile, introrse, two-celled, the cells open- 
ing longitudinally. Ovary free in the bottom of the calyx, sessile or stipitate, many-ovuled, contracted 
into a slender filiform style; stigma terminal, minute or capitate; ovules suspended in two rows from 
the inner angle of the ovary, superposed, anatropous, the micropyle superior. Legume compressed, flat 
or occasionally subterete, before opening circinate, falcate or occasionally almost straight, coriaceous, solid 
or fleshy, rarely submembranaceous, two-valved, the valves, after opening, variously contorted, not elasti- 
cally revolute, usually red on the inner surface, or indehiscent or sometimes breaking into indehiscent 
joints. Seed often surrounded by thin pulp, ovate or orbicular, compressed, suspended transversely, 
destitute of albumen; funicle filiform or variously expanded into a fleshy aril, the hilum near the base 
of the seed ; testa thin, cartilaginous, sometimes marked on the two surfaces of the seed with a faint oval 
or horseshoe-shaped depression or opaque ring. Embryo filling the cavity of the seed; cotyledons 
flat, oval or orbicular, radicle straight, included or slightly exserted. 
Pithecolobium is widely spread through the tropical and subtropical regions of the two worlds, 
especially in the tropics of America,’ where more than half the species are found, and of Asia ;? it is 
represented in tropical Africa® by a single species, and in Australia” by two or perhaps three species. 
About one hundred and twelve species are now recognized.° Four extend to the southern borders of 
1 Bentham, Martius Fl. Brasil. xv. pt. ii. 428.— Grisebach, FT. 8 Oliver, Fl. Trop. Afr. ii. 363. 
Brit. W. Ind. 226. — Hemsley, Bot. Biol. Am. Cent. i. 359. 4 Bentham, Fl. Austral. ii. 423. 
2 Thwaites, Enum. Pl. Zeylan. 100.— Bentham, Fl. Hongk. 5 Bentham, Trans. Linn. Soc. xxx. 570 (Rev. Mim.). 
102. — Brandis, Forest Fl. Brit. Ind. 173. — Hooker f. Fl. Brit. Ind. 
ii. 302. — Oliver, Hooker Icon. xvi. t. 1510 ; xx. t. 1976. 
