Chapter XXXVIII: Section 1: Polypetalæ. Corolla of separate petals (13)

Leaves 1′—3′ long, pubescent or puberulous, with 1—3 pairs of pinnæ, a short slender petiole furnished near the middle with a minute oblong chestnut-brown gland, and linear caducous stipules 1/16′ long; pinnæ short-stalked, with 4—5 pairs of obovate oblique leaflets rounded or truncate at apex and unequally contracted at base into a short petiolule, thick and rigid, 2—3-nerved, inconspicuously reticulate-veined, hoary-pubescent, 1/16′—¼′ long. Flowers fragrant, bright creamy yellow, in dense oblong pubescent spikes, on a peduncle ½′—⅔′ long, and fascicled usually 2 or 3 together toward the end of the branches; calyx obscurely 5-lobed, puberulous on the outer surface, half as long as the petals slightly united at base and pale-tomentose on the margins; stamens ¼′ long; ovary long-stalked, covered with long pale hairs. Fruit fully grown at midsummer and hanging unopened on the branches until winter or the following spring, compressed, straight or slightly falcate, obliquely narrowed at base into a short stalk, acute or rounded at apex, more or less contracted between the seeds, 2′—4′ long, ½′—¾′ wide, curling and often contorted when fully ripe, the valves thin and membranaceous, thick-margined, light brown, conspicuously transversely reticulate-veined; seeds nearly orbicular, compressed, dark brown and lustrous, ¼′ in diameter, marked by small oval depressions.

A tree, rarely 30° high, with a trunk 10′—12′ in diameter, numerous spreading branches, and striately angled puberulous or in Texas glabrous pale brown branchlets faintly tinged with red and armed with stout recurved infrastipular spines flat at base, and ¼′ long and broad. Bark of the trunk about ⅛′ thick, furrowed, the surface separating into thin narrow scales. Wood heavy, very hard, strong, close-grained, durable, rich brown or red, with thin light yellow sapwood of 5 or 6 layers of annual growth.

Distribution. Dry gravelly mesas, the sides of low cañons and the banks of mountain streams; valley of the Rio Grande, western Texas, through southern New Mexico and Arizona to southern California, ranging northward in Arizona to the rim of the Grand Cañon of the Colorado River, and to Clark County, Nevada; in northern Mexico, and in Lower California to the eastern base of the San Pedro Mártir Mountains.

4. LEUCÆNA Benth.

Trees or shrubs, with slender unarmed branches. Leaves persistent, abruptly bipinnate, with numerous pinnæ and small leaflets in many pairs, petiolate, the petioles often furnished with a conspicuous gland below the lower pair of pinnæ; stipules minute and caducous, or becoming spinescent and persistent. Flowers minute, white, mostly perfect, sessile or short-pedicellate, in the axils of small peltate bracts villose at apex, in globose many-flowered pedunculate heads, the peduncles in axillary fascicles or in leafless terminal racemes; calyx tubular-campanulate, minutely 5-toothed; petals 5, free, acute or rounded at apex, narrowed at base; stamens 10, free, inserted under the ovary, exserted; filaments filiform; anthers oblong, versatile; ovary stipitate, contracted into a long slender style, with a minute terminal slightly dilated stigma. Legume many-seeded, stipitate, linear, compressed, dehiscent, the valves thickened on the margins, rigid, thin, continuous within, their outer coat thin and papery, dark-colored, the inner rather thicker, woody, pale brown. Seeds obovoid, compressed, transverse, the hilum near the base, suspended on a long slender funicle; seed-coat thin, crustaceous, brown and lustrous; embryo inclosed on its two sides by a thin layer of horny albumen; radicle slightly exserted.

Leucæna with nine or ten species is confined to the warmer parts of America from western Texas to Venezuela and Peru, and to the islands of the Pacific Ocean from New Caledonia to Tahiti, where one species has been recognized. Of the indigenous species found in the territory of the United States, three are arborescent. _Leucæna glauca_ L., a small tree or shrub, cultivated in all warm countries, and a native probably of tropical America, is now naturalized on Key West, Florida.

The generic name, from λευχαίνω, refers to the color of the flowers.

CONSPECTUS OF THE NORTH AMERICAN SPECIES.

Peduncles bibracteolate at apex; stipules becoming spinescent.
Leaves 10—14-pinnate; pinnæ with 15—30 pairs of leaflets; blade of
the bract of the flower produced into a short point.
1. L. Greggii (E).
Leaves 2—4-pinnate; pinnæ with 4—8 pairs of leaflets; blade of the
bract of the flower produced into a long slender villose tip.
2. L. retusa (E).
Peduncles without bracts; stipules minute, caducous; leaves
30—36-pinnate; pinnæ with 30—60 pairs of leaflets.
3. L. pulverulenta (E).

1. Leucæna Greggii S. Wats.

Leaves 6′—7′ long and broad, with a slender rachis furnished on the upper side with a single elongated bottle-shaped gland between the stalks of each pair of pinnæ; pinnæ 10—14, remote, short-stalked, with 15—30 pairs of leaflets; stipules gradually narrowed into a long slender point, becoming rigid and spinescent, ⅓′ to nearly ½′ long and persistent for two or three years; leaflets lanceolate, acute or acuminate, often somewhat falcate, nearly sessile or short-petiolulate, full and rounded toward the base on the lower margin, nearly straight on the upper margin, gray-green, ultimately nearly glabrous, ¼′—⅓′ long, about ⅛′ wide, with a narrow midvein and obscure lateral nerves. Flowers on slender pedicels, in heads ¾′—1′ in diameter, on stout peduncles 2′—3′ long furnished at apex with 2 irregularly 3-lobed bracts, and solitary or in pairs; calyx coated with hairs only near the apex, much shorter than the spatulate glabrous more or less boat-shaped petals; ovary villose with a few short scattered hairs. Fruit 6′-8′ long, ⅓′—½′ wide, narrowed below into a short stout stipe, acuminate and crowned at apex with the thickened style, ⅓′—¾′ long, cinereo-pubescent until nearly fully grown, becoming nearly glabrous at maturity, much compressed, with narrow wing-like margins; seeds conspicuously notched by the hilum, ½′ long and ⅓′ wide.

A tree, 15°-20° high, with a stem 4′—5′ in diameter, and stout zigzag red-brown branchlets marked by numerous pale lenticels, coated at first with short spreading lustrous yellow deciduous hairs found also on the young petioles and lower surface of the unfolding leaflets, the peduncles of the flower-heads and their bracts. Bark about ⅜′ thick, dark brown, divided into low ridges and broken on the surface into small closely appressed persistent scales. Wood heavy, hard, close-grained, rich brown streaked with red, with thin clear sapwood.

Distribution. Mountain ravines and the steep banks of streams; western Texas from the valley of the upper San Saba River to that of Devil’s River; and southward into Mexico.

2. Leucæna retusa Benth.

Leaves 3′ or 4′ long and 4′ or 5′ wide, with a slender petiole and rachis and 2-4 pairs of pinnæ 6′-10′ long, remote, long-stalked, with 4-8 pairs of short-stalked leaflets furnished between their stems with a single globose white gland found also occasionally on the upper side of the rachis between the stems of the pinnæ; stipules ovate, gradually narrowed into a long slender tip, ½′ in length, often persistent through the season; leaflets obliquely obovate or elliptic, rounded and apiculate at apex, obliquely rounded or cuneate at the unsymmetric base, entire, short-petiolulate, villose-pubescent like the rachis and petiole when they first appear, soon, glabrous, and at maturity thin, blue-green, ¾′—1′ long and ⅓′—½′ wide, with a slender midrib, and prominent veins extending obliquely toward the apex of the leaflet, those of the lowest pair more prominent and starting from near its base. Flowers short-stalked in the axil of a peltate bract, its blade produced into a long slender villose tip, appearing continuously from April until October in dense globose heads ¾′ in diameter, on villose bibracteolate axillary, single or fascicled peduncles 1½′—3′ in length; calyx thin, tubular, 5-toothed at apex; petals narrow-oblong, hardly longer than the calyx; stamens 10, shorter than the bract of the flower; anthers glabrous. Fruit solitary or clustered, on a puberulous peduncle 3′-5′ in length, 6′-10′ long, ⅓′—½′ wide, gradually narrowed below into a stout stipe, the acuminate apex terminating in the thickened persistent style, glabrous and dark reddish brown; seeds ⅓′ long and ¼′ wide.

A tree, occasionally 25° high, with a trunk 6′-8′ in diameter, and slender branchlets pubescent when they first appear, becoming puberulous and orange-brown or reddish brown at the end of their first season; more often a shrub.

Distribution. Texas; steep rocky hillsides, and on the summits of limestone bluffs; (Uvalde, Valverde, Kemble, Real and Jeff Davis Counties).

3. Leucæna pulverulenta Benth. Mimosa.

Leaves 4′-7′ long and 3′-4′ wide, with a slender petiole usually marked by a large dark oblong gland between the somewhat enlarged base and the lowest pair of the 30-36 nearly sessile crowded pinnæ, each with 30-60 pairs of leaflets, and minute caducous stipules, when they unfold covered like the peduncles and flower-buds with dense hoary tomentum, and at maturity puberulous on the petiole and rachis; leaflets linear, acute, rather oblique at base by the greater development of the upper side, sessile or very short-petiolulate, pale bright green, ⅙′—¼′ long. Flowers sessile, fragrant, in heads ½′ in diameter, appearing in succession as the branches grow from early spring to midsummer, on slender peduncles 1′—1½′ long and fascicled in the axils of upper leaves; calyx one fourth as long as the acute petals and like them pilose on the outer surface; stamens twice as long as the petals; ovary coated with long pale hairs. Fruit conspicuously thick-margined, 4′-14′ long, long-stalked, tipped with a short straight or recurved point, usually in pairs on a peduncle thickened at apex; seeds 5/16′ long.

A tree, 50°-60° high, with a straight trunk 18′-20′ in diameter, separating 20°-30° from the ground into slender spreading branches forming a loose round head, and branchlets at first more or less striately grooved and thickly coated with pulverulent caducous tomentum, becoming at the end of a few weeks terete, pale cinnamon-brown and puberulous. Bark about ¼′ thick, bright cinnamon-brown, and roughened by thick persistent scales. Wood heavy, hard, very close-grained, rich dark brown, with thin clear yellow sapwood of 2 or 3 layers of annual growth; considered valuable, and sometimes manufactured into lumber.

Distribution. Rich moist soil of river banks and the borders of lagoons and small streams; valley of the lower Rio Grande; in Texas only for a few miles near its mouth; more abundant from Matamoras to Monterey in Nuevo Leon; and southward to the neighborhood of the City of Mexico.

Occasionally planted as a shade and ornamental tree in the towns of the lower Rio Grande valley and in New Orleans, Louisiana.

5. PROSOPIS L. Mesquite.

Trees or shrubs, with branches without a terminal bud and armed with geminate supra-axillary persistent spines, and small obtuse axillary buds covered with acute apiculate dark brown scales. Leaves alternate on branches of the year and fascicled in earlier axils, deciduous, usually 2 rarely 3-4-pinnate, with many-foliolate pinnæ; petioles glandular at apex with a minute gland, and tipped with the small spinescent rachis; stipules linear, membranaceous or spinescent, deciduous. Flowers greenish white, nearly sessile, in axillary pedunculate spikes; calyx campanulate, 5-toothed, or slightly 5-lobed, deciduous; petals 5, connate below the middle or ultimately free, glabrous or tomentose on the inner surface toward the apex, sometimes puberulous on the outer surface; stamens 10, free, inserted with the petals on the margin of a minute disk adnate to the calyx-tube, those opposite the lobes of the calyx rather longer than the others; filaments filiform; anthers oblong, versatile, their connective tipped with a minute deciduous gland, the cells opening by marginal sutures; ovary stipitate, villose; style filiform, with a minute terminal stigma. Legume linear, compressed, or subterete, straight or falcate, or contorted or twisted into a more or less regular spiral, indehiscent; the outer coat thin, woody, pale yellow, inclosing a thick spongy inner coat of sweet pulp containing the seeds placed obliquely and separately inclosed, their envelopes forming nut-like joints. Seeds oblong, compressed, the hilum near the base; seed-coat crustaceous, light brown, lustrous; embryo surrounded by a layer of horny albumen; radicle short, slightly exserted.

Prosopis is distributed in the New World from southern Kansas to Patagonia, and in the Old World is confined to tropical Africa, and to southwestern and tropical Asia. Sixteen or seventeen species have been distinguished. Of the three species found in the territory of the United States two are small trees.

Prosopis produces hard durable wood, particularly valuable as fuel, and the pods are used as fodder.

The generic name is from προσωπίς, employed by Dioscorides as a name of the Burdock.

CONSPECTUS OF THE NORTH AMERICAN ARBORESCENT SPECIES.

Legume compressed or ultimately convex; pinnæ 12—22-foliolate.
1. P. juliflora (C, E, G, H).
Legume thick, spirally twisted; pinnæ 10—16-foliolate.
2. P. pubescens (E, F, G, H).

1. Prosopis juliflora DC. Mesquite. Honey Locust.

Leaves with 2 or rarely 4 pinnæ, and slender terete petioles abruptly enlarged and glandular at base; stipules linear, acute, membranaceous, deciduous. Flowers appearing in successive crops from May to the middle of July, fragrant, about 1/12′ long, on short pedicels, in slender cylindric spikes 1½′—4′ long, on stout peduncles ½′—¾′ in length; calyx glabrous or puberulous, about one fourth as long as the narrowly oblong acute petals, glabrous or puberulous on the outer surface and covered on the inner surface toward the apex with hoary tomentum; stamens twice as long as the corolla, the dark-colored connective of the anther-cells furnished at apex with a stalked gland; ovary short-stalked, clothed with silky hairs. Fruit in drooping clusters, linear, at first flat, becoming subterete at maturity, constricted between the 10-20 seeds, straight or falcate, contracted at the ends, 4′—9′ long, ¼′—½′ wide; seeds about ¼′ long.

A low tree, with a large thick taproot descending frequently to the depth of 40°-50°, and furnished with radiating horizontal roots spreading in all directions and forming a dense mat, a trunk 6′—8′ in diameter, divided a short distance above the ground into many irregularly arranged crooked branches forming a loose straggling head, and slender branchlets at first pale yellow-green, turning darker in their second year, furnished in the axils of the leaves of their first season with short spur-like excrescences covered with chaffy scales, and armed with stout straight terete supra-axillary persistent spines ½′—2′ long, or rarely unarmed; more often a shrub, with numerous stems only a few feet high. Bark of the trunk thick, dark reddish brown, divided by shallow fissures, the surface separating into short thick scales. Wood heavy, close-grained, rich dark brown or sometimes red, with thin clear yellow sapwood; almost indestructible in contact with the soil, and largely used for fence-posts, railway-ties, the underpinnings of buildings, and occasionally in the manufacture of furniture, the fellies of wheels, and the pavements of city streets; the best fuel of the region, and largely made into charcoal. The ripe pods supply Mexicans and Indians with a nutritious food, and are devoured by most herbivorous animals. A gum, resembling gum-arabic, exudes from the stems.

Distribution. Western Texas and eastern New Mexico, and on the island of Jamaica; eastward and westward diverging into two extreme forms. These are

Prosopis juliflora var. glandulosa Cock.

Leaves 8′—10′ long, 2-pinnate, with long slender petioles, the pinnæ 12—20-foliolate; leaflets distant, linear, mostly acute, glabrous, dark green, often 2′ long and ⅛′—¼′ wide. Flowers with a usually glabrous calyx. Fruit occasionally conspicuously constricted between the seeds (f. _constricta_ Sarg.).

A round-topped tree, often 20° high, with a trunk a foot in diameter, and long gracefully drooping branches forming a symmetrical round-topped head.

Distribution. Eastern Texas to western Louisiana (near Shreveport, Caddo Parish), western Oklahoma and southern Kansas, and southward into northern Mexico. The common Mesquite of eastern Texas; reappearing with rather shorter and more crowded leaflets in Arizona, southern California, and Lower California.

Prosopis juliflora var. velutina Sarg.

Leaves 5′—6′ long, often fascicled, 2—4-pinnate, cinereo-pubescent, with short petioles, the pinnæ 12-22-foliolate; leaflets oblong or linear-oblong, obtuse or acute, crowded, pale green, ¼′—½′ long. Flowers in densely-flowered spikes 2′—3′ long; calyx villose.

A tree, often 50° high, with a trunk 2° in diameter, covered with rough dark brown bark, and heavy irregularly arranged usually crooked branches.

Distribution. Dry valleys of southern Arizona and of Sonora.

2. Prosopis pubescens Benth. Screw Bean. Screw Pod Mesquite.

Leaves canescently pubescent, 2′—3′ long, with a slender petiole ⅓′—⅔′ in length, and pinnæ 1½′—2′ long and 10—16-foliolate; stipules spinescent, deciduous; leaflets oblong or somewhat falcate, acute, sessile or short-petiolulate, often apiculate, conspicuously reticulate-veined, ⅓′—⅔′ long, ⅛′ wide. Flowers beginning to open in early spring, and produced in successive crops from the axils of minute scarious bracts, in dense or interrupted cylindric spikes 2′—3′ long; calyx obscurely 5-lobed, pubescent on the outer surface, one third to one fourth as long as the narrow acute petals coated on the inner surface near the apex with thick white tomentum, and slightly puberulous on the outer surface; ovary and young fruit hoary-tomentose. Fruit ripening throughout the summer and falling in the autumn, in dense racemes, sessile, twisted with from 12—20 turns into a narrow straight spiral 1′—2′ long; seeds 1/16′ long.

A tree, 25°-30° high, with a slender trunk sometimes a foot in diameter, and terete branches canescently pubescent or glabrate when they first appear, becoming glabrous and light red-brown in their third year, and armed with stout spines ⅓′—½′ long. Bark of the trunk thick, light brown tinged with red, separating in long thin persistent ribbon-like scales. Wood heavy, exceedingly hard, close-grained, not strong, light brown, with thin lighter colored sapwood of 6 or 7 layers of annual growth; used as fuel and occasionally for fencing. The sweet, nutritious legumes are valued as fodder.

Distribution. Sandy or gravelly bottom-lands; valley of the Rio Grande in western Texas, and through New Mexico and Arizona to southern Utah and Nevada, and to San Diego County, California, and northern Mexico; attaining its largest size in the United States in the valleys of the lower Colorado and Gila Rivers, Arizona.

6. CERCIS L.

Trees or shrubs, with scaly bark, slender unarmed branchlets prolonged by an upper axillary bud, marked by numerous minute pale lenticels, and in their first winter by small elevated horizontal leaf-scars showing the ends of two large fibro-vascular bundles, and small scaly obtuse axillary buds covered by imbricated ovate chestnut-brown scales. Leaves simple, entire, 5—7-nerved with prominent nerves, long-petiolate, deciduous; petioles slender, terete, abruptly enlarged at apex; stipules ovate, acute, small, membranaceous, caducous. Flowers appearing in early spring before or with the leaves on thin jointed pedicels, in simple fascicles or racemose clusters produced on branches of the previous or earlier years, or on the trunk, with small scale-like bracts often imbricated at the base of the inflorescence, and minute bractlets; calyx disciferous, short-turbinate, purplish, persistent, the tube oblique at base, campanulate, enlarged on the lower side, 5-toothed, the short broad teeth imbricated in the bud; corolla subpapilionaceous; petals nearly equal, rose color, oblong-ovate, rounded at apex, unguiculate, slightly auricled on one side of the base of the blade, the upper petal slightly smaller and inclosed in the bud by the wing-petals encircled by the broader slightly imbricated keel-petals; stamens 10, inserted in 2 rows on the margin of the thin disk, free, declinate, those of the inner row opposite the petals and rather shorter than the others; filaments enlarged and pilose below the middle, persistent until the fruit is grown; anthers uniform, oblong, attached on the back near the base; ovary short-stalked, inserted obliquely in the bottom of the calyx-tube; style filiform, fleshy, incurved, with a stout obtuse terminal stigma; ovules 2-ranked, attached to the inner angle of the ovary. Legume stalked, oblong or broad-linear, straight on the upper edge, curved on the lower edge, acute at the ends, compressed, tipped with the thickened remnants of the style, many-seeded, 2-valved, the valves coriaceo-membranaceous, many-veined, tardily dehiscent by the dorsal and often by the wing-margined ventral suture, dark red-purple and lustrous at maturity. Seeds suspended transversely on a slender funicle, ovoid or oblong, compressed, the small depressed hilum near the apex; seed-coat crustaceous, bright reddish brown; embryo surrounded by a thin layer of horny albumen, compressed; cotyledons oval, flat, the radicle short, straight or obliquely incurved, slightly exserted.

Cercis is confined to eastern and western North America, southern Europe, and to southwestern, central and eastern Asia. Of the eight species now distinguished, three occur in North America. Two of these are arborescent.

The generic name is from κερκίς, the Greek name of the European species, from a fancied resemblance of the fruit to the weaver’s implement of that name.

CONSPECTUS OF THE NORTH AMERICAN ARBORESCENT SPECIES.

Flowers in sessile clusters; leaves ovate, acute, cordate or truncate
at base.
1. C. canadensis (A, C).
Flowers fascicled or slightly racemose; leaves reniform.
2. C. reniformis (C).

1. Cercis canadensis L. Redbud. Judas-tree.

Leaves broad-ovate, acute or acuminate and often abruptly contracted at apex into a short broad point, truncate or more or less cordate at base, entire, glabrous with the exception of axillary tufts of white hairs, or sometimes more or less pubescent below, 3′—5′ long and broad; turning in the autumn before falling bright clear yellow; petioles 2′—5′ in length. Flowers ½′ long, on pedicels ⅓′—½′ in length and fascicled 4-8 together; rarely white (var. _alba_ Rehdr.). Fruit fully grown in the south by the end of May and at the north at midsummer, and then pink or rose color, 2½′—3½′ long, falling late in the autumn or in early winter; seeds about ¼′ long.

A tree, sometimes 40°-50° high, with a straight trunk usually separating 10°-12° from the ground into stout branches covered with smooth light brown or gray bark, and forming an upright or often a wide flat head, and slender glabrous somewhat angled branchlets, brown and lustrous during their first season, becoming dull and darker the following year and ultimately dark or grayish brown. Bark of the trunk about ½′ thick and divided by deep longitudinal fissures into long narrow plates, the bright red-brown surface separating into thin scales. Wood heavy, hard, not strong, close-grained, rich dark brown tinged with red, with thin lighter colored sapwood of 8-10 layers of annual growth.

Distribution. Borders of streams and rich bottom-lands, forming, especially west of the Alleghany Mountains, an abundant undergrowth to the forest; valley of the Delaware River, New Jersey, central and southern Pennsylvania southward to northern Florida, northern Alabama and southern Mississippi (Crystal Springs, Copiah County), and westward to southwestern Ontario (Point Pelee, Essex County), and through southern Michigan to southern Iowa, southeastern Nebraska, eastern Kansas, western Oklahoma (Major and Dewey Counties), Louisiana, and the valley of the Brazos River, Texas; and on the Sierra Madre of Nuevo Leon; common and of its largest size in southwestern Arkansas, Oklahoma and eastern Texas, and in early spring a conspicuous feature of the landscape.

Often cultivated as an ornamental tree in the northeastern states, and occasionally in western Europe.

2. Cercis reniformis Engl. Redbud.

_Cercis texensis_ Sarg.

Leaves reniform, when they unfold light green and slightly pilose, and at maturity subcoriaceous, dark green and lustrous on the upper surface, paler, glabrous or pubescent on the lower surface, and 2′—3′ in diameter; petioles 1½′—2′ in length. Flowers about ½′ long, on slender pedicels ½′—¾′ in length and fascicled in sessile clusters, or occasionally racemose. Fruit 2′—4′ long, ½′—1′ wide; seeds ¼′ long.

A slender tree, occasionally 20° or rarely 40° high, with a trunk 6′-12′ in diameter, and glabrous branchlets marked by numerous minute white lenticels, light reddish brown during their first and second years, becoming dark brown in their third season; more often a shrub, sending up numerous stems and forming dense thickets only a few feet high. Bark of the trunk and branches thin, smooth, light gray. Wood heavy, hard, close-grained brown streaked with yellow, with thin lighter colored sapwood of 5 or 6 layers of annual growth.

Distribution. Limestone hills and ridges; neighborhood of Dallas, Dallas County, Texas to the Sierra Madre of Nuevo Leon; common in the valley of the upper Colorado River, Texas; of its largest size on the mountains of northeastern Mexico.

7. GYMNOCLADUS Lam.

Trees, with stout unarmed blunt branchlets with a thick pith, prolonged by axillary buds, rough deeply fissured bark, thick fleshy roots, and minute buds depressed in pubescent cavities of the bark, 2 in the axil of each leaf, superposed, remote, the lower and smaller sterile and nearly surrounded by the enlarged base of the petiole, their scales 2, ovate, rounded at apex, coated with thick dark brown tomentum, infolded one over the other, accrescent with the young shoots. Leaves deciduous, unequally bipinnate; pinnæ many-foliolulate, with 1 or 2 pairs of the lowest pinnæ reduced to single leaflets; pinnæ and leaflets usually alternate; leaflets thin, ovate, entire, petiolulate; stipules foliaceous, early deciduous. Flowers regular, diœcious, greenish white, long-pedicellate, the slender pedicels from the axils of long lanceolate scarious caducous bracts, bibracteolate near the middle; staminate flowers in a short terminal racemose corymb; pistillate flowers in elongated terminal racemes, on pedicels much longer than those of the staminate flowers; calyx tubular, elongated, 10-ribbed, lined with a thin glandular disk, 5-lobed, the lobes, lanceolate, acute, nearly equal, erect; petals 4 or 5, oblong, rounded or acute at apex, pubescent, as long as the calyx-lobes or rather longer and twice as broad, inserted on the margin of the disk, spreading or reflexed; stamens 10, free, inserted with the petals, erect, included; filaments filiform, pilose, those opposite the petals shorter than the others; anthers oblong, uniform, small and sterile in the pistillate flower; ovary sessile or slightly stipitate, acute; styles short, erect, obliquely dilated into 2 broad lobes stigmatic on their inner surface, rudimentary or 0 in the sterile flower; ovules numerous, suspended from the angle opposite the posterior petals. Legume oblong, subfalcate, turgid or slightly compressed, several-seeded, 2-valved, tardily dehiscent, the thin tough woody valves thickened on the margins into narrow wings, pulpy between the seeds. Seeds ovoid or slightly obovoid, suspended by a long slender funicle; seed-coat thick, bony, brown and opaque, of 3 layers; embryo surrounded by a thin layer of horny albumen; cotyledons ovate, orange-colored, thick and fleshy, the radicle short, erect.

Gymnocladus, with two species, is confined to eastern North America and to central China.

Gymnocladus is slightly astringent and purgative, and the detersive pulp surrounding the seeds of the Asiatic species is used in China as a substitute for soap.

The generic name, from γυµνός and κλάδος, relates to the stout branchlets destitute of spray.

1. Gymnocladus dioicus K. Koch. Kentucky Coffee-tree. Mahogany.

Leaves 1°—3° long, 18′—24′ wide, obovate, 5—9 pinnate, the pinnæ 6—14-foliolate, covered when they unfold with hoary tomentum except on the upper surface of the ovate acute leaflets, often mucronate, especially while young, cuneate or irregularly rounded at base, pink at first, soon becoming bronze-green and lustrous, glabrous on the upper surface with the exception of a few scattered hairs along the midrib, and at maturity thin, obscurely veined, dark green above, pale yellow-green and glabrous below, with the exception of a few short hairs scattered along the narrow midrib, 2′—2½′ long and 1′ wide, or those replacing the lowest or occasionally the 2 lower pairs of pinnæ sometimes twice as large; turning bright clear yellow in the autumn before falling; petioles abruptly and conspicuously enlarged at base, at first hoary-tomentose, becoming glabrous at maturity; stipules lanceolate or slightly obovate, glandular-serrate toward the apex, ⅓′ long. Flowers: inflorescence of the staminate tree 3′—4′ long, the lower branches usually 3 or 4-flowered; inflorescence of the pistillate tree 10′—12′ long, the flowers on stout pedicels 1′—2½′ long or twice to five times as long as those of the staminate flowers; flowers hoary-tomentose in the bud; calyx ⅔′ long, covered on the outer surface when the flowers open with pale hairs and on the inner surface with hoary tomentum; petals keeled, pilose on the back, slightly grooved, tomentose on the inner surface; anthers bright orange color; ovary hairy. Fruit 6′—10′ long, 1½′—2′ wide, dark red-brown, covered with a glaucous bloom, on stout stalks 1′—2′ in length, remaining unopened on the branches through the winter; seeds separated by a thick layer of dark-colored sweet pulp, ¾′ long.

A tree, 75°—110° high, with a trunk 2°—3° in diameter, usually dividing 10°—15° from the ground into 3 or 4 principal stems spreading slightly and forming a narrow round-topped head, or occasionally sending up a tall straight shaft destitute of branches for 70°—80°, and branchlets coated when they first appear with short dense pubescence faintly tinged with red, bearing at their base the conspicuous orange-green obovate pubescent bud-scales, ¼′—⅓′ thick at the end of their first season, very blunt, dark brown, often slightly pilose, marked by orange-colored lenticels, and roughened by the large pale broadly heart-shaped leaf-scars displaying the ends of 3 or 4 conspicuous fibro-vascular bundles. Bark of the trunk ¾′—1′ thick, deeply fissured, dark gray tinged with red, and roughened by small persistent scales. Wood heavy although not hard, strong, coarse-grained, very durable in contact with the soil, rich light brown tinged with red, with thin lighter colored sapwood of 5 or 6 layers of annual growth; occasionally used in cabinet-making and for fence-posts, rails, and in construction. The seeds were formerly used as a substitute for coffee; a decoction of the fresh green pulp of the unripe fruit is used in homœopathic practice.

Distribution. Bottom-lands in rich soil; central and western New York and Franklin County, Pennsylvania, through southern Ontario and southern Michigan to southeastern Minnesota, northeastern and southern Iowa, southeastern South Dakota, eastern and northeastern Nebraska, eastern Kansas, southwestern Arkansas and northeastern Oklahoma (with isolated stations in Woods and Custer Counties and in the western parts of Cimarron County); in Eastern Kentucky, and western and middle Tennessee; nowhere common.

Occasionally cultivated in the gardens and parks of the eastern United States, and of northern and central Europe.

8. GLEDITSIA L.

Trees, with furrowed bark, slender terete slightly zigzag branchlets thickened at the apex and prolonged by axillary buds, thick fibrous roots, the trunk and branches often armed with stout simple or branched spines or abortive branchlets developed from supra-axillary or adventitious buds imbedded in the bark. Winter-buds minute, 3 or 4 together, superposed, the 2 or 3 lower without scales and covered by the scar left by the falling of the petiole, the upper larger, nearly surrounded by the base of the petiole and covered by small scurfy scales. Leaves long-petiolate, often fascicled in earlier axils, abruptly pinnate or bipinnate, the pinnæ increasing in length from the base to the apex of the leaf, the lowest sometimes reduced to single leaflets; deciduous; leaflets thin, their margins irregularly crenate, without stipels; stipules minute, caducous. Flowers regular, polygamous, minute, green or white on short pedicels, in axillary or lateral simple or fascicled racemes, with minute scale-like caducous bracts; calyx campanulate, lined with the disk, 3—5-lobed, the narrow lobes nearly equal; petals as many as the lobes of the calyx, nearly equal; stamens 6—10, inserted with the petals on the margin of the disk, exserted; filaments free, filiform, erect; anthers uniform, much smaller and abortive in the pistillate flower; ovary subsessile, rarely bicarpellary, rudimentary or 0 in the staminate flower; styles short; stigma terminal, more or less dilated, often oblique; ovules 2 or many, suspended from the angle opposite the posterior petal. Legume compressed, many-seeded, elongated, straight and indehiscent, or 1—3-seeded, ovoid and tardily dehiscent. Seeds transverse, ovoid to suborbicular, flattened, attached by a long slender funicle; seed-coat thin, crustaceous, light brown; embryo surrounded by a layer of horny orange-colored albumen; cotyledons subfoliaceous, compressed; radicle short, erect, slightly exserted.

Gleditsia is confined to eastern North America, where three species occur, southwestern Asia, China, Formosa, Japan, and west tropical Africa. It produces strong, durable, coarse-grained wood. In Japan the pods are used as a substitute for soap.

The generic name is in honor of Johann Gottlieb Gleditsch (1714—1786), professor of botany at Berlin.

CONSPECTUS OF THE NORTH AMERICAN ARBORESCENT SPECIES.

Legume linear-oblong, elongated, many-seeded, indehiscent.
Legume 12′—18′ long, with pulp between the seeds; ovary
hoary-tomentose.
1. G. triacanthos (A, C).
Legume 4′—5′ long, without pulp between the seeds.
2. G. texana (C).
Legume oval, oblique, 1—3-seeded, without pulp, tardily dehiscent;
ovary glabrous.
3. G. aquatica (A, C).

1. Gleditsia triacanthos L. Honey Locust.

Leaves 7′—8′ long, 18—28-foliolulate or sometimes bipinnate, with 4—7 pairs of pinnæ, those of the upper pair 4′—5′ long, when they unfold hoary-tomentose, and at maturity pubescent on the petiole and rachis, the short stout petiolules, and the under surface of the midrib of the oblong-lanceolate leaflets, unequal at base, acute or slightly rounded at apex, remotely crenulate-serrate, dark green and lustrous above, dull yellow-green below, 1′—1½′ long and ½′ wide; turning in the autumn pale clear yellow. Flowers appearing in June when the leaves are nearly fully grown from the axils of leaves of previous years; the staminate in short many-flowered pubescent racemes 2′—2½′ long and often clustered; the pistillate in slender graceful few-flowered usually solitary racemes 2½′—3½′ long; calyx campanulate, narrowed at base, the acute lobes thickened, revolute and ciliate on the margins, villose with pale hairs, rather shorter than and half as wide as the erect acute petals; filaments pilose toward the base; anthers green; pistil rarely of 2 carpels, hoary-tomentose. Fruit 12′—18′ long, dark brown, pilose and slightly falcate, with straight thickened margins, 2 or 3 together in short racemes on stalks 1′—1½′ long, their walls thin and tough, contracting in drying by a number of corkscrew twists, and falling late in the autumn or early in winter; seeds oval, ⅓′ long, separated by thick succulent pulp.

A tree, 75°—140° high, with a trunk 2°—3° or occasionally 5°—6° in diameter, slender spreading somewhat pendulous branches forming a broad open rather flat-topped head, and branchlets marked by minute lenticels, at first light reddish brown and slightly puberulous, soon becoming lustrous and red tinged with green, and in their second year greenish brown and armed with stout rigid long-pointed simple or 3-forked spines at first red, and bright chestnut-brown when fully grown, or rarely unarmed (var. _inermis_ Pursh.). Bark of the trunk ½′—¾′ thick, divided by deep fissures into long narrow longitudinal ridges and roughened on the surface by small persistent scales. Wood hard, strong, coarse-grained, very durable in contact with the ground, red or bright red-brown, with thin pale sapwood of 10—12 layers of annual growth; largely used for fence-posts and rails, for the hubs of wheels, and in construction.

Distribution. Borders of streams and intervale lands, in moist fertile soil, usually growing singly or occasionally covering almost exclusively considerable areas; less commonly on dry sterile gravelly hills; western slope of the Alleghany Mountains of Pennsylvania, westward through southern Ontario and southern Michigan to southeastern Minnesota, southern Iowa, southeastern South Dakota, eastern Nebraska, eastern Kansas, and Oklahoma to the Salt Fork of the Arkansas River (near Alva, Woods County) and to creek valleys near Cache, Comanche County (_G. W. Stevens_), and southward to northern Alabama, Mississippi and western Florida and to the valley of the Brazos River, eastern Texas; and in the cañon of Paloduro Creek near Canyon, Randall County, northwestern Texas (_E. J. Palmer_); in Pennsylvania and West Virginia occasionally on the eastern slopes of the Appalachian Mountains; attaining its largest size in the valleys of small streams in southern Indiana and Illinois; now often naturalized in the region east of the Alleghany Mountains. The var. _inermis_, the prevailing form in Taney County, southern Missouri.

Often cultivated as an ornamental and shade tree in all countries of temperate climates.

2. Gleditsia texana Sarg. Locust.

Leaves 6′—7′ long, 12—22-foliolulate, with a slender rachis at first puberulous, ultimately glabrous, or often bipinnate, usually with 6 or 7 pairs of pinnæ, the lower pairs frequently reduced to single large leaflets; leaflets oblong-ovate, often somewhat falcate, rounded or acute or apiculate at apex, obliquely rounded at base, finely crenately serrate, thick and firm in texture, dark green and lustrous above, pale below, ½′—1′ long, with a short petiolule coated while young, like the base of the slender orange-colored midrib, with soft pale hairs. Flowers appearing toward the end of April, the staminate dark orange-yellow, in slender glabrous often clustered racemes lengthening after the flowers begin to open and finally 3′—4′ in length; calyx campanulate, with acute lobes thickened on the margins, villose-pubescent and rather shorter and narrower than the puberulous petals; stamens with slender filaments villose near the base and green anthers; pistillate flowers unknown. Fruit 4′—5′ long, 1′ wide, straight, much compressed, rounded and short-pointed at apex, full and rounded at the broad base, thin-walled, dark chestnut-brown, puberulous, slightly thickened on the margins, many-seeded, without pulp; seeds oval, compressed, dark chestnut-brown, very lustrous, ½′ long.

A tree, 100°—120° high, with a trunk rarely exceeding 2½° in diameter, ascending and spreading branches forming a narrow head, and comparatively slender more or less zigzag branchlets roughened by numerous small round lenticels, light orange-brown when they first appear, gray or orange-brown during their first year, ashy gray the following season, and unarmed. Bark thin and smooth.

Distribution. Only in a single grove on the bottom-lands of the Brazos River, near the town of Brazoria, Brazoria County, Texas.

3. Gleditsia aquatica Marsh. Water Locust.

Leaves 5′—8′ long, 12—20-foliolate, or bipinnate, with 3 or 4 pairs of pinnæ; leaflets ovate-oblong, usually rounded or rarely emarginate at apex, unequally cuneate at base, slightly and remotely crenate or often entire below the middle, glabrous with the exception of a few hairs on the short stout petiolule, dull yellow-green and lustrous on the upper surface, dark green on the lower surface, about 1′ long and ⅓′—½′ wide. Flowers appearing in May and June after the leaves are fully grown on short stout purple puberulous pedicels, in slender racemes 3′—4′ long; calyx-tube covered with orange-brown pubescence, the lobes narrow, acute, slightly pilose on the two surfaces, as long as but narrower than the green erect petals rounded at apex; filaments hairy toward the base; anthers large, green; ovary long-stipitate, glabrous. Fruit fully grown in August, pendent in graceful racemes, obliquely ovoid, long-stalked, crowned with a short stout tip, thin, 1′—2′ long, 1′ broad, without pulp, its valves thin, tough, papery, bright chestnut-brown, lustrous and somewhat thickened on the margins; seeds 1 or rarely 2 or 3, flat, nearly orbicular, orange-brown, ½′ in diameter.

A tree, 50°—60° high, with a short trunk 2°—2½° in diameter, usually dividing a few feet from the ground into stout spreading often contorted branches forming a wide irregular flat-topped head, and glabrous orange-brown branchlets becoming in their second year gray or reddish brown, marked by occasional large pale lenticels, and armed with usually flattened simple or short-branched straight or falcate sharp rigid spines 3′—5′ long, about ½′ broad at the base, and dark red-brown and lustrous. Bark ⅛′—¼′ thick, smooth, dull gray or reddish brown, and divided by shallow fissures into small plate-like scales. Wood heavy, very hard and strong, coarse-grained, rich bright brown tinged with red, with thick light clear yellow sapwood of about 40 layers of annual growth.

Distribution. Eastern South Carolina to Florida, through the coast region of the Gulf states to the valley of the Brazos River, Texas, and northward through western Louisiana and southern Arkansas to northwestern Mississippi, middle Kentucky and Tennessee, the bottoms of the Mississippi at La Pointe, Saint Charles County, Missouri, western and southern Illinois and southwestern Indiana; rare east of the Mississippi River and only in deep river swamps; very abundant and of its largest size westward on rich bottom-lands; in Louisiana and Arkansas often occupying extensive tracts submerged during a considerable part of the year.

9. PARKINSONIA L.

Trees or shrubs, with smooth thin bark and terete branches often armed with simple or 3-forked spines. Leaves abruptly bipinnate, alternate or fascicled from earlier axils, short-petiolate, the rachis short and spinescent, with 2—4 secondary elongated rachises bearing numerous minute opposite entire leaflets without stipels; stipules short, persistent and spinescent, or caducous. Flowers perfect on thin elongated jointed pedicels from the axils of minute caducous bracts, in slender axillary solitary or fascicled racemes; calyx short-campanulate, 5-lobed, the lobes slightly imbricated or subvalvate in the bud, narrow, membranaceous, nearly equal, becoming reflexed, deciduous; petals bright yellow, unguiculate, much longer than the lobes of the calyx, spreading, the upper petal rather broader than the others and glandular at the base of the claw; stamens 10, inserted in 2 rows on the margin of the thin disk, free, slightly declinate, those of the outer row opposite the sepals and rather longer than the others; filaments villose below the middle, the upper filament enlarged at base and gibbous on the upper side; anthers uniform, versatile; ovary short-stipitate, pilose, contracted into a slender filiform incurved style infolded in the bud and tipped with a minute stigma; ovules numerous, suspended from the inner angle of the ovary. Legume linear, torulose, acuminate at the ends, 2-valved, the valves thin, convex by the growth of the seeds, contracted between and beyond them, longitudinally striate. Seeds oblong, suspended longitudinally on a slender funicle; hilum minute, near the apex; seed-coat thin, crustaceous, light brown; embryo inclosed on the sides only by thick layers of horny albumen; cotyledons oval, flat, slightly fleshy, the radicle very short and straight.

Parkinsonia, with four species, is confined to the warm parts of America and to southern Africa. Two species occur within the limits of the United States.

The genus is named for John Parkinson (1567—1650), an English botanical author, and herbalist to James I.

CONSPECTUS OF THE NORTH AMERICAN SPECIES.

Flowers in long slender racemes; petals imbricated in the bud; stamens
shorter than the petals; legume 1—8-seeded, 12′—18′ long; leaves
7′—8′ long; rachis of the pinnæ flat, wing-margined,
50—60-foliolate; branches with spines.
1. P. aculeata (G, H).
Flowers in short racemes; petals valvate in the bud; stamens longer
than the petals; legume 1—2-seeded; leaves about 1′ long; rachis
of the pinnæ terete, 8—12-foliolate; branches without spines.
2. P. microphylla (G, H).

1. Parkinsonia aculeata L. Retama. Horse Bean.

Leaves of two forms, short-petiolate, persistent, light green and glabrous, except for a few hairs on the lower part of the young secondary rachis, 12′—18′ long; primary leaves on young branches, with 2—4 pinnæ, and a spinescent rachis developing into a stout ridged persistent short-pointed chestnut-brown spine 1′—1½′ long and marked near the base by the prominent scars left by the fall of the pinnæ; stipules persistent, appearing as lateral spiny branches on the spines; secondary leaves fascicled from the axils of the primary leaves, nearly sessile with a short terete spinescent rachis and 2 pinnæ; pinnæ flat, 12′—18′ in length, wing-margined, acute at apex, with 25—30 pairs of ovate or obovate petiolulate leaflets, 1/16′—⅛′ long. Flowers appearing on the growing branches during the spring and summer, and in the tropics throughout the year, on slender pedicels ⅓′—½′ in length, in slender erect racemes 5′—6′ long; petals bright yellow, the upper one marked near the base on the inner surface with conspicuous red spots; stamens shorter than the petals. Fruit hanging on pedicels ½′—¾′ in length, in graceful racemes, 2′—4′ long, long-pointed, dark orange-brown, slightly pilose, compressed between the remote seeds; seeds ⅓′ long, nearly terete, with thick albumen and a bright yellow embryo.

A tree, 18°—30° high, with a trunk sometimes a foot in diameter, usually separating 6°—8° from the ground into slender spreading somewhat pendulous branches forming a wide graceful head, and slightly zigzag branchlets puberulous and yellow-green during their first season, becoming glabrous, gray or light orange color and roughened by lenticels in their second and third years. Bark of the trunk about ⅛′ thick, brown tinged with red, the generally smooth surface broken into small persistent plate-like scales. Wood heavy, hard, close-grained, with very thick lighter colored sapwood tinged with yellow.

Distribution. Low moist soil, valley of the lower Rio Grande, Texas; common in northern Mexico and in the valley of the lower Colorado River, Arizona; widely distributed in Lower California; naturalized on Key West, the Bahamas, the West Indian islands, and in many other tropical countries.

Cultivated in most warm countries as an ornament of gardens, and to form hedges.

2. Parkinsonia microphylla Torr.

Leaves 1′ long, pale, densely tomentose when they unfold, pubescent at maturity, deciduous at the end of a few weeks; petiole ¼′ long; rachis short, rarely spinescent; leaflets in 4—6 pairs, distant, entire, sessile, broad-oblong or nearly orbicular, obtuse or somewhat acute at apex, oblique at base, ⅙′ long; stipules caducous. Flowers opening in May or early June before the leaves, on slender pedicels, in racemes 1′ or less long from the axils of leaves of the previous year, pale yellow; stamens longer than the petals. Fruit persistent on the branches for at least a year, frequently 1 or 2, rarely 3-seeded, 2′—3′ long, slightly puberulous, especially toward the base, with a long acuminate often falcate apex; seeds compressed, ⅓′ long, with a bright green embryo.

An intricately branched tree, occasionally 20°—25° high, with a trunk a foot in diameter, and stout pale yellow-green rigid branchlets terminating in a stout spine, covered at first with deciduous tomentum, slightly puberulous during their first and second seasons, and often marked by the persistent scales of undeveloped buds. Bark dark orange color, generally smooth, although sometimes roughened by scattered clusters of short pale gray horizontal ridges, becoming on old trees ¼′ thick; more often a shrub, frequently only a few feet tall. Wood heavy, hard, close-grained, dark orange-brown streaked with red, with thick light brown or yellow sapwood of 25—30 layers of annual growth.

Distribution. Deserts of southern Arizona and adjacent regions of California and Sonora, and in northern Lower California; known to attain the size and habits of a tree only in the neighborhood of Wickenburg, Maricopa County, Arizona.

10. CERCIDIUM Tul.

Trees or shrubs, with stout tortuous branches, covered with bright green bark and armed with slender straight axillary spines, and minute obtuse buds. Leaves alternate, abruptly pinnate, petiolate, early deciduous; pinnæ 2 or occasionally 3, 6—8-foliolate; stipules inconspicuous or 0; leaflets ovate or obovate, without stipels. Flowers perfect in short few-flowered axillary racemes, solitary or fascicled, with minute membranaceous early deciduous bracts; calyx 5-lobed, the lobes equal, acute, reflexed at maturity, their margins scarious, slightly revolute; petals orbicular or short-oblong, unguiculate, bright yellow, the upper petal broader and longer clawed than the others, slightly auriculate at base of the blade, the claw conspicuously glandular at base; stamens 10, inserted with the petals on the margin of the disk, free, slightly declinate, exserted; filaments filiform, pilose below, the upper filament enlarged at base and gibbous on the upper side; anthers uniform, ovoid, versatile; ovary short-stalked, inserted at the base of the calyx-tube; styles slender, involute, infolded in the bud, with a minute terminal stigma; ovules suspended from the angle of the ovary opposite the posterior petal. Legume linear-oblong, compressed or somewhat turgid, straight or slightly contracted between the seeds, thickened on the margins, the ventral suture acute, or slightly grooved, tipped with the remnants of the style, tardily dehiscent, 2-valved, the valves membranaceous or subcoriaceous, obliquely veined. Seeds suspended longitudinally on a long slender funicle, ovoid, compressed, the minute hilum near the apex; seed-coat thin, crustaceous; embryo compressed, light green, covered on the sides only by a thin layer of horny albumen; cotyledons oval, flat, rather fleshy; radicle very short, erect, near the hilum.

Cercidium is confined to the warmer parts of the New World, where it is distributed with four or five species from the southern borders of the United States through Mexico, Central America, and Venezuela to Mendoza. Of the three species found within the territory of the United States two are small trees.

Cercidium produces hard wood sometimes used as fuel.

The generic name, from κερκίδιον, refers to the fancied resemblance of the legume to the weaver’s instrument of that name.

CONSPECTUS OF THE NORTH AMERICAN ARBORESCENT SPECIES.

Legume compressed, with straight margins; leaflets green, slightly
glandular.
1. C. floridum (E).
Legume somewhat turgid, the margins often slightly contracted between
the seeds; leaflets glaucous.
2. C. Torreyanum (G, H).

1. Cercidium floridum Benth. Green-barked Acacia.

Leaves 1′—1½′ long, with 2 or rarely 3 pinnæ, a broad pubescent petiole and rachis, and oval or somewhat obovate dull green puberulous minutely glandular leaflets about 1/16′ in length, rounded or slightly emarginate at apex, and when they unfold covered on the lower surface with scattered white hairs; petiolules short, stout, pubescent; appearing in April and deciduous in October. Flowers opening with the leaves, and produced in successive crops during three or four months, ¾′ in diameter, on slender pedicels, in 4 or 5-flowered racemes 1½′—2′ long, with small acute minute membranaceous caducous bracts. Fruit compressed, oblong, straight or slightly falcate, acute, narrowly and acutely margined on the ventral suture, glabrous, 2 or 3-seeded, 2′—2½′ long, ½′ broad, tardily dehiscent, the valves papery, yellow tinged with brown on the outer surface, and bright orange color within; seeds ⅓′ long.

A tree, 18°—20° high, with a short crooked trunk 8′—10′ in diameter, stout spreading branches covered with thin smooth bright green bark, forming a low wide head, and branchlets light or dark olive-green, slightly puberulous at first, soon glabrous, marked by occasional black lenticels, and armed with slender spines 1′ or less in length. Bark 1/16′ thick, light brown tinged with red, with numerous short horizontal light gray ridge-like excrescences. Wood light, soft, close-grained, pale yellow tinged with green, with thick lighter colored sapwood.

Distribution. Shores of Matagorda Bay to Hidalgo and Valverde Counties, Texas, and in northern Mexico; not common in Texas; very abundant and a conspicuous feature of vegetation in Mexico from the mouth of the Rio Grande to the foothills of the Sierra Madre.

2. Cercidium Torreyanum Sarg. Green-barked Acacia. Palo Verde.

Leaves few and scattered, 1′ long, hoary-tomentose when they first appear, puberulous at maturity, with a slender petiole and 2 pinnæ, with 2 or 3 pairs of oblong obtuse glaucous leaflets narrowed toward the somewhat oblique base, 1/12′—⅙′ long; unfolding in March and April and falling almost immediately when fully grown. Flowers ¾′ in diameter, on slender pedicels ¾′—1′ long, in 4 or 5-flowered racemes about 1′ in length, with small acute membranaceous caducous bracts. Fruit ripening and falling in July, 3′—4′ long, ¼′—⅓′ wide, 2—8-seeded, slightly turgid, often somewhat contracted between the seeds, frequently grooved on the ventral suture; seeds turgid, ⅓′ long.

A low intricately branched tree, leafless for most of the year, 25°—30° high, with a short often inclining trunk 18′—20′ in diameter, stout spreading branches covered with yellow or olive-green bark, forming a wide open irregular head, and glabrous slightly zigzag light yellow or pale olive-green and glaucous branchlets armed with thin straight or curved spines ¼′ long. Bark thin, smooth, pale olive-green, becoming near the base of old trunks reddish brown, ⅛′ thick, furrowed and separating into thick plate-like scales. Wood heavy, not strong, soft, close-grained, light brown, with clear light yellow sapwood.

Distribution. Sides of low cañons and depressions, and sandhills of the desert; valley of the lower Gila River, Arizona, to the Colorado Desert of southern California, and southward into Sonora and Lower California; when in flower in early spring the conspicuous and most beautiful feature of the vegetation of the Colorado Desert.

11. SOPHORA L.

Trees or shrubs, with minute scaly buds, unarmed terete branches prolonged by an upper axillary bud, and fibrous roots. Leaves unequally pinnate, with numerous small or few and ample thin or coriaceous leaflets; stipules minute, deciduous; stipels often 0. Flowers in terminal or axillary racemes, with linear minute deciduous bracts and bractlets; calyx broad-campanulate, often slightly turbinate or obconic at base, obliquely truncate, the short teeth nearly equal or the 2 upper subconnate and often somewhat larger than the others; disk cupuliform, glandular, adnate to the calyx-tube; corolla papilionaceous; petals white or violet blue, unguiculate; standard obovate or orbicular, usually shorter than the oblong, suberect keel-petals, as long or rather longer than the oblong-oblique wings, overlapping each other at the back, barely united; stamens free, or 9 of them slightly united at base, uniform; anthers attached on the back near the middle; ovary short-stipitate, contracted into an incurved style, with a minute truncate or slightly rounded capitate stigma; ovules numerous, suspended from the inner angle of the ovary, superposed, amphitropous. Legume terete, much contracted between the seeds, woody or fleshy, usually many-seeded, each seed inclosed in a separate cell, indehiscent. Seed oblong or oval, sometimes somewhat compressed; seed-coat thick, membranaceous or crustaceous; cotyledons thick and fleshy; radicle short and straight or more or less elongated and incurved.

Sophora is scattered over the warmer parts of the two hemispheres, with about twenty species of trees, shrubs or herbs; of the six North American species two are small trees. Several of the species produce valuable wood, and from the pods and flower-buds of the Chinese _Sophora japonica_ L., a dye is obtained used to dye white cloth yellow and blue cloth green. This tree is often cultivated as an ornament of parks and gardens in northern China, Japan, the eastern United States, and in western, central, and southern Europe.

The generic name is from _Sophera_, the Arabic name of some tree with pea-shaped flowers.

CONSPECTUS OF THE NORTH AMERICAN ARBORESCENT SPECIES.

Flowers violet blue, in terminal racemes; the upper calyx-lobes larger
than the others and united; legume woody; seeds without albumen;
leaves coriaceous, persistent.
1. S. secundiflora (C, E, H).
Flowers white, in axillary racemes; calyx-lobes equal; legume fleshy;
seeds with albumen; leaves thin, deciduous.
2. S. affinis (C).

1. Sophora secundiflora DC. Frijolito. Coral Bean.