Part 99

Tubercles of the branches full and rounded below the areolæ. Joints pale olive color, easily separable, their tubercles broad, mammillate; spines yellow; flowers pink; fruit proliferous, usually spineless, often sterile. 1. O. fulgida (H). Joints green or purple, their tubercles narrow, ovoid; spines white to reddish brown; flowers purple; fruit yellow, sparingly spinescent, rarely proliferous. 2. O. spinosior (H). Tubercles of the branches not full and rounded below the areolæ; joints elongated, dark green or purple, their tubercles elongated; spines brown or reddish brown; flowers green, tinted with red or yellow; fruit green, spinescent, rarely proliferous. 3. O. versicolor (H).

1. Opuntia fulgida Engelm. Cholla.

Leaves light green, gradually narrowed to the acuminate apex, ½′—1′ long. Flowers appearing from June to September, the earliest from tubercles at the end of the branches of the previous year, the others from the terminal tubercles of the immature fruit developed from the earliest flowers of the season, 1′ in diameter when fully expanded, with ovaries nearly 1′ long, 8—10 obtuse crenulate sepals, 5 erect stigmas, and 8 light pink petals, those of the outer ranks cuneate, retuse, crenulate on the margins, shorter than the lanceolate acute petals of the inner ranks, the whole strongly reflexed at maturity. Fruit proliferous, oval, rounded, 1′—1¼′ long and nearly as broad, more or less tuberculate, conspicuously marked by large pale tomentose areolæ bearing numerous small bristles, usually spineless or occasionally armed with small weak spines, hanging in pendulous clusters usually of 6 or 7 and occasionally of 40—50 fruits in a cluster, one growing from the other in continuous succession, the first the largest and containing perfect seeds, the others frequently sterile, dull green when fully ripe, with dry flesh, falling usually during the first winter or occasionally persistent on the branches during the second season, and then developing flowers from the tubercles; seeds compressed, thin, very angular, 1/12′—⅙′ in diameter.

A tree, with a more or less flexuous trunk occasionally 12° in height and sometimes a foot in diameter, a symmetric head of stout wide-spreading branches and thick pendulous joints sometimes almost hidden by the long conspicuous spines and beginning to develop their woody skeletons during their second or occasionally during their third season, the terminal or ultimate joints ovoid or ovoid-cylindric, tumid, crowded at the end of the limbs, pale olive color, 3′—8′ long, often 2′ in diameter, with broad ovoid-oblong tubercles, ½′—¾′ in length. Areolæ of pale straw-colored tomentum and short slender pale bristles, each areola bearing at first 5—15 stout stellate-spreading light yellow spines of nearly equal length, ¾′-1′ long and inclosed in loose lustrous sheaths, additional spines developing in succeeding years at the upper margin of the areolæ, the tubercles of old branches being sometimes furnished with from 40-60 spines persistent on the branches for 4-6 years. Bark of the trunk and of the large limbs about ¼′ thick, separating freely on the surface into large thin loosely attached scales varying in color from brown to nearly black on the largest stems, and unarmed, the spines mostly falling with the outer layers from branches 3′—4′ thick. Wood of old trunks light, hard, pale yellow, with broad conspicuous medullary rays, well marked layers of annual growth, and a thick pith.

Distribution. Plains of Arizona south of the Colorado plateau, and in the adjacent region of Sonora; not rare; apparently most abundant and of its largest size in the United States on the mesas near Tucson, Pima County, at altitudes between 2000° and 3000°.

2. Opuntia spinosior Toumey. Tassajo.

Leaves terete, tapering gradually to the setulose apex, about ¼′ long, remaining on the branches from four to six weeks. Flowers opening in April and May and remaining open for two or three days, 2′—2½′ in diameter, with ovaries about 1′ long, obovate sepals, broad-obovate dark purple petals, sensitive red stamens, and a 6—9-parted stigma. Fruits clustered at the end of the branches of the previous year, persistent during the winter and occasionally during the following summer and then sometimes proliferous, oval or rarely globose or hemispheric, frequently 2′ long and 1½′ thick, with yellow acrid flesh and 20—30 tubercles very prominent during the summer, nearly disappearing as the fruit ripens and enlarges, leaving it marked only by the small oval areolæ covered with short bristles, and bearing numerous slender spines deciduous in December as the fruit begins to turn yellow; seeds nearly orbicular, slightly or not at all beaked, ⅙′—⅕′ in diameter, and marked by linear conspicuous commissures.

A tree, with an erect trunk occasionally 10° high and 5′-10′ in diameter, numerous stout spreading limbs forming an open irregular head, and branches with joints 4′—12′ long and ¾′—1′ thick, covered with a thick epidermis varying from green to purple, and usually developing woody skeletons during their second season, their tubercles prominent, compressed, ovoid, ⅓′—½′ long. Areolæ oval, clothed with pale tomentum and short light brown bristles, their spines 5—15 on the tubercles of young joints and 30—50 on those of older branches, and slender, white to light reddish brown, closely invested in white glistening sheaths, stellate-spreading, ½′—¾′ long, those in the interior sometimes considerably longer than the radial spines. Bark of the trunk and of the larger limbs about ¼′ thick, spineless, nearly black, broken into elongated ridges, and finally much roughened by numerous closely appressed scales. Wood light, soft, pale reddish brown, and conspicuously reticulate, with conspicuous medullary rays and well defined layers of annual growth; sometimes used in the manufacture of light furniture, canes, picture-frames, and other small articles.

Distribution. Widely scattered over the mesas of southern Arizona south of the Colorado plateau and of the adjacent regions of Sonora.

3. Opuntia versicolor Coult.

Leaves terete, abruptly narrowed to the spinescent apex, ⅓′—½′ long, persistent on the branches from four to six weeks. Flowers opening in May, about 1½′ in diameter, with ovaries ⅝′ long, broad-ovate acute sepals, and narrow obovate petals rounded above and green tinged with red or with yellow. Fruit usually clavate, 2′—2½′ long, nearly 1½′ in diameter, with areolæ generally only above the middle and usually furnished with 1—3 slender reflexed persistent spines about ½′ long, or occasionally spineless, rarely nearly spherical and only about ¾′ in diameter, ripening from December to February, and at maturity the same color as the joint on which it grows, usually withering, drying, and splitting open on the tree, or remaining fleshy and persistent on the branches until the end of the following summer, and sometimes through a second winter, or often becoming imbedded in the end of a more or less elongated joint; seeds irregularly angled, with narrow commissures.

A tree, with an erect trunk occasionally 6°—8° high and 8′ in diameter, numerous stout irregularly spreading or often upright branches, and cylindric terminal joints generally 6′—12′ but sometimes 2° in length, ¾′—1′ in diameter, and covered with a thick dark green or purple epidermis, marked by linear flattened tubercles, their woody skeletons usually formed during their second season. Areolæ large, oval, clothed with gray wool, generally bearing a cluster of small bristles, and slender stellate-spreading brown or reddish brown spines, with close early deciduous straw-colored sheaths, 4—14 and on old tubercles 20—25 in number, the inner 1—4 in number, usually deflexed and unequal in length, the longest about ⅓′ long and longer than the radial spines. Bark of the trunk and of the large branches smooth, light brown or purple, usually unarmed, ½′—¾′ thick, finally separating into small closely appressed black scales. Wood reticulate, hard, compact, light reddish brown and rather lustrous, with thin conspicuous medullary rays, well-defined layers of annual growth, and thick pale or nearly white sapwood.

Distribution. Foothills and low mountain slopes of southern Arizona and northern Sonora; very abundant.

XLVI. RHIZOPHORACEÆ.

Glabrous trees or shrubs, with terete branchlets, and usually opposite coriaceous entire persistent leaves, with interpetiolar stipules. Flowers in axillary clusters; calyx-lobes valvate in the bud, persistent; petals inserted on the tube of the calyx and as many as its lobes; stamens inserted at the base of a conspicuous disk; anthers 2-celled, the cells opening longitudinally; pistil of 2—5 united carpels; ovary 2—5-celled; ovules usually 2 in each cell, suspended from its apex, collateral, anatropous; raphe ventral; micropyle superior. Fruit usually indehiscent, 1-celled and 1-seeded.

The Mangrove family is tropical, with most of its seventeen genera confined to the Old World.

1. RHIZOPHORA L. Mangrove.

Trees, with pithy branchlets, thick astringent bark, and adventitious fleshy roots. Leaves ovate or elliptic, glabrous, petiolate; stipules elongated, acuminate, infolding the bud, caducous. Flowers perfect, yellow or creamy white, sessile or pedicellate, bibracteolate, the bractlets united into an involucral cup, in pedunculate dichotomously or trichotomously branched clusters, the base of their branches surrounded by an involucre of 2 ovate 3-lobed persistent bracts, or 1-flowered; calyx 4-lobed, the lobes acute, coriaceous, ribbed on the inner surface and thickened on the margins, two or three times longer than the turbinate globose tube, reflexed at maturity, persistent; petals 4, induplicate in the bud, alternate with and longer than the calyx-lobes, inserted on a fleshy disk-like ring in the mouth of the calyx-tube, involute on the margins, coated on the inner surface with long pale hairs, or flat and naked, caducous; stamens 8—12; filaments short or 0; anthers attached at the base, introrse, elongated, connivent, areolate; ovary partly inferior, conic, 2-celled, contracted into two subulate spreading styles stigmatic at apex. Fruit a conic coriaceous berry surrounded by the reflexed calyx-lobes and perforated at the apex by the germinating embryo. Seed germinating in the fruit before falling, the apex surrounded by a thin albuminous cup-like aril; seed-coat thick and fleshy; embryo surrounded by a thin layer of albumen; cotyledons dark purple; radicle elongated, clavate, and when fully grown separating from the narrow exserted woody tube inclosing the plumule and developed from the cotyledons after the ripening of the fruit.

Rhizophora with three species is widely and generally distributed on the shores of tidal marshes in the tropical regions of the two hemispheres, one specie reaching those of southern Florida. It possesses astringent properties; the bark has been used in tanning leather, in dyeing, and as a febrifuge. The wood is hard, durable, and dark-colored. By means of the aerial germination of its seeds and in its power to develop roots from trunks and branches, Rhizophora is especially adapted to maintain itself on low tidal shores and is an important factor in protecting and extending them into the ocean. Roots springing from the stems at a considerable distance above the ground and arching outward descend into the water and fix themselves in the mud beneath, while roots growing down from the branches enter the ground and gradually thicken into stems. The fully grown radicle ready to put forth roots and leaves, and often 10′—12′ long, is thicker and heavier at the root end than at the other, and in detaching itself from the cotyledons and in falling the heavy end sticks in the mud, while the plumule at the other end, held above the shallow surface of the water, soon unfolds its leaves.

The generic name, from ῥίζα and φέρειν, was used by early authors to designate various climbing plants with thickened roots.

1. Rhizophora Mangle L.

Leaves ovate or elliptic, rounded or acute at apex, gradually narrowed at base, dark green and very lustrous on the upper surface, paler on the lower surface, 3½′—5′ long and 1′—2′ wide, with slightly thickened margins, a broad midrib, and reticulate veinlets; persistent for one or two years; petioles ½′—1½′ in length; stipules lanceolate, acute, 1½′ long, deciduous as the leaf unfolds. Flowers produced through the year, 1′ in diameter, pedicellate, in 2 or 3-flowered clusters on peduncles 1½′ long from the axils of young leaves; petals pale yellow, coated on the inner surface with long pale hairs; stamens 8 with villose filaments. Fruit 1′ long, rusty brown, slightly roughened by minute bosses, the hard woody thick-walled tube developed from the cotyledons protruding ½′—⅔′ from its apex after the germination of the seed, covering the plumule, and holding the dark brown radicle marked with occasional orange-colored lenticels and when fully grown 10′—12′ long and ¼′—⅓′ thick near the apex.

A round-topped bushy tree, with spreading branches usually 15°—20° high, forming almost impenetrable thickets with its numerous aerial roots, or occasionally 70°—80° high, with a tall straight trunk clear of branches for more than half its length, a narrow head, and stout glabrous dark red-brown branchlets, becoming lighter colored in their second year and then conspicuously marked by large oval slightly elevated leaf-scars. Bark of young stems and of the branches smooth, light reddish brown, becoming on old trunks ⅓′—½′ thick, and gray faintly tinged with red, the surface irregularly fissured and broken into thin appressed scales. Wood exceedingly heavy, hard, close-grained, strong, dark reddish brown streaked with lighter brown, with pale sapwood of 40—50 layers of annual growth; used for fuel and wharf-piles.

Distribution. Shores of Florida from Mosquito Inlet on the east coast and Cedar Keys on the west coast to the southern keys; most abundant south of latitude 29°, following the coast with wide thickets and ascending the rivers for many miles; on Cape Sable and the shores of Bay Biscayne sometimes growing at a little distance from the coast on ground not submerged by the tide, and here attaining its largest size, with tall straight trunks and few aerial roots; on Bermuda, the Bahamas, the Antilles, the west coast of Mexico, lower California, the Galapagos Islands, and from Central America along the northeast coast of South America to the limits of the tropics.

XLVII. COMBRETACEÆ.

Trees or shrubs, with astringent juice, naked buds, and alternate or opposite simple entire coriaceous persistent leaves, without stipules. Flowers regular, perfect, or polygamous; calyx 5-lobed, the lobes valvate in the bud; petals 5, valvate in the bud, inserted at the base of the calyx, or 0; disk epigynous; stamens 5—10, inserted on the limb of the calyx; filaments slender, filiform, distinct, exserted; anthers introrse, 2-celled, the cells opening longitudinally; ovary 1-celled; style slender, subulate; stigma minute, terminal, entire; ovules usually 2, suspended from the apex of the cell, collateral, anatropous; raphe ventral; micropyle superior. Fruit drupaceous, often crowned with the accrescent calyx. Seed solitary; albumen 0; embryo straight, with convolute cotyledons; radicle minute, turned toward the hilum.

Of the fifteen genera of this family, widely distributed through the tropics, three have arborescent representatives in southern Florida.

CONSPECTUS OF THE ARBORESCENT GENERA OF THE UNITED STATES.

Corolla 0; leaves alternate. Calyx persistent; flowers in spikes; seeds without wings. 1. Bucida. Calyx deciduous; flowers in capitate heads; seeds winged. 2. Conocarpus. Corolla of 5 petals; calyx persistent; leaves opposite. 3. Laguncularia.

1. BUCIDA L.

A tree or shrub, with terete often spinescent branchlets. Leaves crowded at the end of spur-like lateral branchlets much thickened and roughened by the large elevated crowded leaf-scars, alternate, obovate to oblong-lanceolate, rounded and slightly emarginate or minutely apiculate at apex, gradually narrowed and cuneate at base, coriaceous, bluish green on the upper surface and yellow-green on the lower surface, pubescent while young, especially beneath, and glabrous at maturity with the exception of rufous hairs on the under surface of the stout midrib, and on the short stout petiole. Flowers perfect, greenish white, hairy on the outer surface, sessile in the axils of minute bracts, in lax elongated axillary clustered rufous-pubescent spikes; calyx-tube ovoid, constricted above the ovary, the limb campanulate, 5-lobed, the lobes valvate in the bud, persistent; petals 0; stamens 10, in two ranks, inflexed in the bud, unequal, 5 longer than the others and inserted opposite the calyx-lobes under the hairy 5-lobed disk, the others shorter, alternate with them and inserted higher on the calyx-tube; filaments incurved near the apex; anthers minute, sagittate; ovary included in the tube of the calyx; style thickened and villose at the base; ovules suspended on an elongated slender funiculus. Fruit ovoid, conic, oblique, and more or less falcate, irregularly 5-angled, coriaceous, light brown, puberulous on the outer surface, with thin membranaceous flesh inseparable from the crustaceous stone porous toward the interior. Seed ovoid, acute; seed-coat coriaceous, chestnut-brown; cotyledons fleshy; radicle superior.

Bucida with a single species is confined to tropical America, where it is distributed from southern Florida and the Bahama Islands through the West Indies to Guiana and Central America.

The generic name is from βοῦς, in allusion to the fancied resemblance of the fruit to the horns of an ox.

1. Bucida Buceras L. Black Olive-tree.

Leaves 2′—3′ long, 1′—1½′ wide, their petioles ⅓′—½′ in length. Flowers appearing in Florida in April, ⅛′ long, on spikes 1½′—3′ in length. Fruit about ⅛′ long.

A tree, with a single straight trunk, or often with a short prostrate stem 2°—3° in diameter, producing several straight upright secondary stems 40°—50° high and 12′—18′ in diameter, stout branches spreading nearly at right angles with the trunk and forming a broad head, and branchlets clothed when they first appear with short pale rufous pubescence mostly persistent for two or three years, becoming light reddish brown and covered with bark separating into thin narrow shreds. Bark of the trunk and of the large branches thick, gray tinged with orange-brown, and broken into short appressed scales. Wood exceedingly heavy, hard, close-grained, light yellow-brown sometimes slightly streaked with orange, with thick clear pale yellow sapwood of 30—40 layers of annual growth. The bark has been used in tanning leather.

Distribution. Florida, only on Elliott’s Key; widely distributed in brackish marshes through the West Indies to the shores of the Caribbean Sea and the Bay of Panama.

2. CONOCARPUS L.

A tree or shrub, with angled branchlets. Leaves alternate, short-petiolate, narrow-ovate or obovate, acute, gradually contracted and biglandular at base, glabrous or sericeous. Flowers perfect, minute, in dense capitate heads in narrow leafy terminal panicles, with acute caducous bracts and bractlets coated with pale hairs, on stout hoary-tomentose peduncles bibracteolate near the middle; calyx-tube truncate, obliquely compressed at base, clothed with pale hairs, the limb campanulate, parted to the middle, the lobes ovate, acute, erect, pubescent on the outer and puberulous on the inner surface, deciduous; petals 0; disk 5-lobed, hairy; stamens usually 5, inserted in 1 rank, or rarely 7 or 8 in 2 ranks; anthers cordate, minute; style thickened and villose at base. Fruits scale-like, broad-obovoid, pointed, recurved, and covered at apex with short pale hairs, densely imbricated in ovoid reddish heads; flesh coriaceous, corky, produced into broad lateral wings; stone thin-walled, crustaceous, inseparable from the flesh. Seed irregularly ovoid; seed-coat membranaceous, pale chestnut-brown.

The genus consists of a single species of tropical America and Africa.

The generic name, from χῶνος and καρπὸς, is in allusion to the cone-like shape of the heads of fruits.

1. Conocarpus erecta L. Buttonwood.

Leaves slightly puberulous on the lower surface when they first appear or coated with pale silky persistent pubescence (var. _sericea_, DC.), 2′—4′ long, ½′—1½′ wide, lustrous, dark green or pale on the upper surface, paler on the lower surface, with a broad orange-colored midrib, obscure primary veins, and reticulate veinlets; petioles stout, broad, ½′ in length. Flowers produced throughout the year, in heads ⅓′ in diameter on peduncles ½′—1½′ in length, in panicles 6′—12′ long. Cone of fruit about 1′ in diameter.

A tree, 40°—60° high, with a trunk 20′—30′ in diameter, small branches forming a narrow regular head, and slender branchlets conspicuously winged, light red-brown, usually glabrous, or silky pubescent (var. _sericea_, DC.), becoming terete and marked by large orbicular leaf-scars in their second year; or sometimes a low shrub, with semiprostrate stems. Bark of the trunk dark brown, divided by irregular reticulating fissures into broad flat ridges broken on the surface into small thin appressed scales. Wood very heavy, hard, strong, close-grained, dark yellow-brown, with thin darker colored sapwood of about 10 layers of annual growth; burning slowly like charcoal and highly valued for fuel. The bark is bitter and astringent, and has been used in tanning leather, and in medicine as an astringent and tonic.

Distribution. Low muddy tide-water shores of lagoons and bays; Florida, Cape Canaveral and Cedar Keys to the southern keys; of its largest size in Florida on Lost Man’s River near Cape Sable; at its northern limits a low shrub; common on the Bahama Islands, in the Antilles, on the shores of Central America and tropical South America, on the Galapagos Islands, and on the west coast of Africa.

3. LAGUNCULARIA Gærtn.