Christi, Nueces County, to the Rio Grande and to Comal and Valverde Counties; in
northeastern Mexico; of tree-like habit and of its largest size on the high sandy banks of
the lower Rio Grande and its tributaries; often covering large areas with dense impenetra-
ble chaparrai.

2. REYNOSIA Griseb.

Trees or shrubs, with rigid unarmed terete branches, and scaly buds. Leaves mostly
opposite, entire, coriaceous, short-pet iolate, reticulate-veined, persistent. Flowers minute,
on stout pedicels bibracteolate near the base and two or three times longer than the flower,
in small axillary sessile umbels; calyx persistent, .3-lobed, the lobes deltoid or ovate, acute or
acuminate, spreading, petaloid, deciduous; disk fleshy; petals 0; stamens 5, inserted on the
margin of the disk, rather shorter than the calyx-lobes; filaments incurved; anthers oval;
ovary free from the disk, almost superior, conic, 2-3-celIed, contracted into a short erect
thick style; stigma 2-3-lobed. Fruit drupaceous; flesh thin; stone crustaceo-membrana-
ceous. Seed ovoid or subglobose; seed-coat very thin, conspicuously rugose and tubercu-
late; embryo axile in copious subcorneous ruminate albumen; cotyledons oblong.

Reynosia is distributed from southern Florida and the Bahama Islands to the Antilles.
Four species are recognized; of these, one, a small tree, extends into southern Florida.

The generic name is in honor of Alvaro Reynoso (1830-1888), the distinguished Cuban
chemist and writer on agriculture and scientific subjects.

1. Reynosia septentrionalis Urb. Red Ironwood. Darling Plum.
Leaves oblong to ovate or obovate, or sometimes nearly orbicular, rounded, truncate or




Fig. 647



frequently emarginate and usually minutely apiculate at apex, gradually narrowed at base
into a short broad petiole, very thick and coriaceous, dark green on the upper, rather paler



RHAMNACE^E 721

or often rufous on the lower surface, I'-l |' long and \' broad, with thickened re volute mar-
gins, a stout broad midrib, about five pairs of primary veins spreading nearly at right angles,
and numerous reticulate veinlets; unfolding in April and remaining on the branches for
one and sometimes for two years. Flowers yellowish green appearing in May, iV long;
sepals ovate, acute. Fruit ripening in Florida in November or frequently not until the
following spring, short-obovoid, \' long, purple or nearly black, edible, with an agreeable
flavor.

A tree, 20-25 high, with a trunk 6'-8' in diameter, stout terete rigid branchlets slightly
puberulous when they first appear, soon becoming glabrous and gray faintly tinged with
red, growing darker in their second season, then often covered by small tubercles and
marked by the prominent elevated leaf-scars. Winter-buds minute, chestnut-brown.
Bark of the trunk rV-i' thick, dark-red-brown, and divided into large plate-like scales.
Wood heavy, exceedingly hard, strong, close-grained, rich dark brown, with light brown
sapwood of 15-20 layers of annual growth.

Distribution. Florida, coast and islands from the Marquesas group to the shores of
Bay Biscayne and the Everglade Keys, Dade County; common and generally distrib-
uted; on the Bahama Islands.

3. KRUGIODENDRON Urb.

A small tree or shrub, with slender unarmed terete branches roughened by numerous
small lenticels, and minute scaly buds. Leaves opposite or obliquely opposite, or some-
times alternate on lower branches, ovate or oval, often emarginate, coriaceous, entire,
short-petiolate, feather- veined, persistent; stipules acuminate, persistent. Flowers green-
ish yellow, on short slender pedicels, in axillary simple or dichotomously branched cymes;
calyx broad-obconic, 5-lobed, the lobes triangular, acute, erect or spreading, conspicuously
crested on the inner surface, deciduous; disk annular, broad, fleshy, 5-lobed, surrounding
the base of the ovary; petals 0; stamens 5, inserted under the margin of the disk; anthers
ovoid or ovoid-orbicular, obtuse; ovary conic, imperfectly 2-celled; styles short and thick,
united nearly to the apex, the branches spreading and stigmatic on the inner face; ovule
ascending from the base of the cell. Fruit 1-seeded, oval or ovoid; flesh thin and black;
wall of the stone thin and bony. Seed ellipsoid, compressed, without albumen ; seed-coat
membranaceous; embryo filling the cavity of the seed; cotyledons thick and fleshy, obovate
or elliptic.

Krugiodendron, with a single species, is confined to southern Florida and the West Indies.

The generic name is in honor of Leopold Krug (1833-1898), a student of the flora of the
Antilles.

1. Krugiodendron ferreum Urb. Bkck Ironwood.

Leaves bright green and lustrous above, pale yellow-green below, glabrous with the excep-
tion of a few scattered hairs on the upper surface and on the petiole, I'-l^' long and f'-l'
wide, with entire or slightly undulate margins; persistent for two or three years; petioles
stout, \' in length. Flowers on bibracteolate pedicels |' long, in 3-5-flowered cymes on
peduncles sometimes \' in length, usually much shorter and often branched near the apex,
on branchlets of the year; calyx about T V long. Fruit generally solitary, \' in length, on
a stem \'-\' long.

A tree, sometimes 30 high, with a trunk 8'-10' in diameter, and slender branchlets at
first green and covered with dense velvety pubescence, becoming glabrous in their second
year, and then gray faintly tinged with red and roughened by small crowded lenticels; gen-
erally much smaller and more often shrubby than arborescent. Bark of the trunk about
\' thick and divided into prominent rounded longitudinal ridges broken on the surface into
short thick light gray scales. Wood exceedingly heavy, hard, strong, close-grained, brittle,
rich orange-brown, with thin lighter colored sapwood.

Distribution. Florida, Cape Canaveral on the east coast to the shores of Bay Biscayne



TREES OF NORTH AMERICA



and on the Everglade Keys, Dade County, near Cape Sable, and on the southern keys;
one of the commonest of the small trees of the region; on the Bahama Islands and on
several of the Antilles.




Fig. 648



4. RHAMNUS L.

Trees or shrubs, with terete often spinescent branches, without a terminal bud, scaly
or naked axillary buds and acrid bitter bark. Leaves alternate or rarely obliquely
opposite, conduplicate in the bud, petiolate, feather- veined, entire or dentate, stipulate.
Flowers perfect or polygamo-dioecious, in axillary simple or compound racemes or fascicled
cymes; calyx campanulate, 4-5-lobed, the lobes triangular-ovate, erect or spreading, keeled
on the inner surface, deciduous; disk thin below, more or less thickened above; petals 5,
inserted on the margin of the disk, ovate, unguiculate, emarginate, infolded round the sta-
mens, deciduous, or 0; stamens 4 or 5; filaments very short; anthers oblong-ovoid or sagit-
tate, rudimentary and sterile in the pistillate flower; ovary free, ovoid, included in the tube
of the calyx, 2-4-celled, rudimentary in the staminate flower; styles united below, with
spreading stigmatic lobes or terminating in a 2-3-lobed obtuse stigma; ovule erect from the
base of the cell. Fruit drupaceous, oblong or spherical; flesh thick and succulent, inclosing
2-4 separable cartilaginous 1-seeded nutlets. Seeds erect, obovoid, grooved longitudinally
on the back, with a cartilaginous seed-coat, the raphe in the groove, or convex on the back,
with a membranaceous seed-coat, the raphe lateral next to one margin of the cotyledons;
embryo large, surrounded by thin fleshy albumen ; cotyledons oval, folia ceous, with revolute
margins, or flat and fleshy.

Rhamnus with about sixty species is widely distributed in nearly all the temperate
and in many of the tropical parts of the world with the exception of Australasia and the
islands of the Pacific Ocean. Of the five species indigenous to the United States three
attain the size of small trees. The fruit and bark of Rhamnus are drastic, and yield
yellow and green dyes. The European Rhamnus cathartica L., the Buckthorn, has long
been used as a hedge plant in northern Europe, and in eastern North America, where it has
now become sparingly naturalized.

The generic name is from pd/j.vos, the classical name of the Buckthorn.

CONSPECTUS OF THE NORTH AMERICAN ARBORESCENT SPECIES.

Flowers polygamo-direcious, in sessile umbels; calyx 4-lobed; petals 0; anthers oblong-
ovoid; lobes of the stigma elongated, spreading; fruit red; seed grooved on the back;
seed-coat cartilaginous; leaves often sharply toothed, persistent; winter-buds scaly.

1. R. crocea (G).



RHAMNACE.E



723



Flowers perfect, in pedunculate umbels; calyx 5-lobed; petals 5; anthers sagittate; lobes
of the stigma short and obtuse; fruit black; seed rounded on the back; seed-coat mem-
branaceous; leaves deciduous; winter-buds naked.

Peduncles shorter than the petioles. 2. R. caroliniana (C).

Peduncles longer than the petioles. :}. R. Purshiana (B, G).

1 . Rhamnus crocea Nutt.

Leaves persistent, often in fascicles, elliptic, broad-ovate to suborbicular, rounded and
often apiculate at apex, glandular-denticulate with minute teeth, coriaceous, yellow-green
and lustrous 011 the upper surface, pale and frequently bronzed or copper color on the lower
surface, glabrous or often puberulous while young, with a prominent midrib and slender
primary veins, i'-f long; petioles short and stout; stipules minute, acuminate. Flowers
polygamo-dioecious, on slender often puberulous pedicels, in small clusters from the axils
of the leaves or of small lanceolate persistent bracts on shoots of the year; calyx 4-lobecl,
with acuminate lobes, about |' long; petals 0; stamens rather shorter than the calyx, with
short stout incurved filaments and large ovoid anthers, minute and rudimentary in the pis-
tillate flower; ovary ovoid, contracted into a long slender style divided above the middle
into two wide-spreading acuminate stigmatic lobes, rudimentary in the staminate flower.
Fruit red, obovoid, slightly grooved or lobed at maturity, j' long, with thin dry flesh and
1-3 nutlets; seed broad-ovoid, pointed at apex, deeply grooved on the back and |' long,
with a thin membranaceous pale chestnut-colored coat.

A shrub, 6'-3 high, with slender rigid often spinescent branchlets forming thickets.

Distribution. Coast mountains of central and southern California. Passing into

Rhamnus crocea var. ilicifolia Greene.

Leaves oval or orbicular, spinulose-dentate, often golden beneath and I'-l^' long and
'-!' wide. Flowers with 4 or occasionally 5 calyx-lobes and stamens.

A tree, occasionally 25 high, with a trunk 6 '-8' in diameter, stout spreading branches,
and slender branchlets yellow-green and puberulous or glabrate when they first appear, be




Fig. 649



coming dark red or reddish brown and glabrous in their second season. Winter-buds ob-
tuse, barely more than iV long, with small puberulous apiculate imbricated scales ciliate
on the margins. Bark of the trunk usually from TV-f ' thick, the dark gray surface slightly
roughened by minute tubercles.

Distribution. California, valley of the Sacramento River southward along the western
slopes of the Sierra Nevada, and on the coast ranges and southern mountains to San Diego



724



TREES OF NORTH AMERICA



County; Arizona, Oak Creek and Sycamore Canons, near Flagstaff, Coconino County,
(P. Lowell), Copper Canon, west of Camp Verde, Yavapai County, and on the Final and
Santa Catalina Mountains.
Passing into

Rhamnus crocea var. insularis Sarg.

A form with larger less prominently toothed leaves sometimes 3' long and 1|' wide,
rather larger flowers, with shorter and broader calyx-lobes a less deeply divided style,




Fig. 650



and larger fruits. A tree often growing to the height of 25-30, flowering later than the
var. Uicifolia, and not uncommon on the islands of the Santa Barbara group and on
the mountains of the adjacent mainland. A form (f. pttosa Trel.) with narrow revolute
leaves densely pilose throughout, occurs in the Santa Maria valley of the mountains near
San Diego.

2. Rhamnus caroliniana Walt. Indian Cherry.

Leaves deciduous, elliptic-oblong or broad-elliptic, acute or acuminate, cuneate or some-
what rounded at base, remotely and obscurely serrate, or crenulate, densely coated when
they unfold with rusty brown tomentum, and at maturity thin, dark yellow-green above,
paler below, glabrous or somewhat hairy on the lower surface, 2'-6' long and 1' to nearly
2' wide, with a prominent yellow midrib and about 6 pairs of conspicuous yellow primary
veins; turning yellow in the autumn before falling; petioles slender, pubescent, \' to nearly
1' in length; stipules nearly triangular. Flowers appearing from April to June when the
leaves are almost fully grown, on slender pedicels about \' long, in few-flowered pubescent
umbels, on peduncles varying from \'-\' in length; calyx 5-lobed, with a narrow 7 turbinate
tube and triangular lobes; petals 5, broad-ovate, deeply notched at apex and folded round
the short stamens; ovary contracted into a long columnar style terminating in a slightly 3-
lobed stigma. Fruit ripening in September and sometimes remaining on the branches until
the beginning of winter, globose, \' in diameter, black, with thin sweet rather dry flesh and
2-4 nutlets; seeds obtuse at apex, rounded on the back, reddish brown, about \' long.

A tree, 30-40 high, with a trunk 6'-8' in diameter, small spreading unarmed branches,
and slender branchlets light red-brown and puberulent or covered with a glaucous bloom
when they first appear, becoming slightly angled, gray, and glabrous, and marked during
their second season by the small horizontal oval leaf-scars; more often a tall shrub, with
numerous stems 15-20 high. Winter-buds naked, hoary-tomentose. Bark of the trunk
about $' thick, slightly furrowed, ashy gray and often marked by large black blotches.
Wood rather hard, light, close-grained, not strong, light brown, with lighter colored sap-
wood of 5 or 6 layers of annual growth.



RHAMNACE^E



725



Distribution. Borders of streams on rich bottom-lands, and on limestone ridges; Vir-
ginia to western Florida and westward through the valley of the Ohio River to southern




Fig. 651

Iowa and southeastern Nebraska, eastern Kansas, the valley of the Washita River, Okla-
homa (Ardman County), and to Kendall, Kerr and Uvalde Counties, western Texas; occa-
sionally tree-like in western Florida and Mississippi, and of its largest size only in southern
Arkansas and the adjacent portions of Texas; very abundant on the limestone barrens of
central Kentucky and Tennessee.

3. Rhamnus Purshiana DC. Bearberry. Coffee-tree.

Leaves deciduous, broad-elliptic, obtuse or bluntly pointed at apex, rounded or slightly
cordate at base, finely serrate, or often nearly entire, with undulate margins, thin, villose
with short hairs on the lower surface and on the veins above, l|'-7' long, l^'-2' wide,
conspicuously netted- veined, with a broad and prominent midrib and primary veins; turn-
ing pale yellow late in the autumn before falling; petioles stout, often pubescent, 5'-!' in
length; stipules membranaceous, acuminate. Flowers on slender pubescent pedicels '-!'
long, in axillary cymes on slender pubescent peduncles ^'-1' in length on shoots of the year;
calyx nearly campanulate, with 5 spreading acuminate lobes; petals 5, minute, ovate,
deeply notched at apex, and folded round the short stamens; stigma 2 or 3-lobed. Fruit
globose or broad-obovoid, black, $'-%' in diameter, slightly or not at all lobed, with thin
rather juicy flesh, and 2 or 3 obovoid nutlets usually \ f long, rounded on the back, flat-
tened on the inner surface, with 2 bony tooth-like enlargements at base, 1 on each side of
the large scar of the hilum, and a thin gray or pale yellow-green shell; seeds obtuse
at apex, rounded on the back* seed-coat thin and papery, yellow-brown on the outer sur-
face, bright Orange color on the inner surface like the cotyledons.

A tree, 35-40 high, with a slender trunk often 18'-20' in diameter, separating 10-15
from the ground into numerous stout upright or sometimes nearly horizontal branches,
and slender branchlets coated at first with fine soft pubescence, pale yellow-green or reddish
brown, and pubescent, glabrous, or covered with scattered hairs in their second season and
then marked by the elevated oval horizontal leaf-scars; often shrubby and occasionally
prostrate. Winter-buds naked, hoary-tomentose. Bark of the trunk rarely more than \'
thick, dark brown to light brown or gray tinged with red, broken on the surface into short
thin scales. Wood light, soft, not strong, brown tinged with red, with thin lighter colored
sapwood. The bark possesses the drastic properties peculiar to that of other species of
the genus, and is a popular domestic remedy in Oregon and California, and under the name
of Cascara Sagrada has been admitted into the American materia medica.



726 TREES OF NORTH AMERICA

Distribution. Rich bottom-lands and the sides of canons, usually in coniferous forests;
shores of Puget Sound eastward along the mountain ranges of northern Washington to the
Bitter Root Mountains of Idaho and the shores of Flat Head Lake, Montana, and south-
ward to central California; Arizona, southern slope of the Grand Canon of the Colorado




Fig. 652

River, Coconino County (A Rehder), Cave Creek Canon, Chiricahua Mountains,
Cochise County (J. W. Tourney).

Occasionally cultivated in the gardens of western Europe and of the eastern United
States.

5. CEANOTHUS L.

Small trees or shrubs, with slender terete branches, without a terminal bud, and small
scaly axillary buds. Leaves petiolate, 3-ribbed from the base, or pinnately veined, per-
sistent in the arborescent species. Flowers on colored pedicels, in umbellate fascicles col-
lected in dense or prolonged terminal or axillary thyrsoid cymes or panicles, blue or white;
calyx colored, with a turbinate or hemispheric tube and 5 triangular membranaceous peta-
loid lobes; disk fleshy, thickened above; petals 5, inserted under the margin of the disk,
unguiculate, wide-spreading, deciduous, the long claw infolded round the stamens; stamens
.">, inserted with and opposite the petals, persistent, filaments spreading; ovary partly im-
mersed in and more or less adnate to the disk, 3-celled, sometimes 3-angled, the angles
often surmounted by a fleshy gland persistent on the fruit; styles short, united below;
stigmas 3-lobed with spreading lobes; ovule erect from the base of the cell. Fruit 3-lobed,
subglobose, with a thin outer coat, soon becoming dry, and separating into 3 crustaceous
or cartilaginous longitudinally 2-valved nutlets. Seeds erect, obovoid, lenticellate, with
a broad basal excrescence surrounding the hilum; seed-coat thin, crustaceous; albumen
fleshy; embryo axile; cotyledons oval or obovate.

Ceanothus is confined to the temperate and warmer regions of North America, with
about thirty species, mostly belonging to California. The leaves, bark, and roots are as-
tringent and tonic. Of the species of the United States three are small trees.

The generic name is from Kedvudos, the classical name of some spiny plant.

CONSPECTUS OF THE ARBORESCENT SPECIES OF THE UNITED STATES.

Branchlets not spinose, leaves 3-ribbed.

Leaves broad-ovate to elliptic, subcordate or rounded at base, pale and tomentose below.

1. C. arboreus (G).



RHAMNACE.E 727

Leaves elliptic, acute at base, glabrous except on the veins below.

2. C. thyrsiflorus (G).

Branchlets spinose; leaves with a single midrib, mostly elliptic, rounded or subcordate at
base, glabrous. 3. C. spinosus (G).

1. Ceanothus arboreus Greene.

Leaves broad-ovate or elliptic, acute, conspicuously glandular-crenate, dark green and
softly puberulent on the upper surface, pale and densely tomentose on the lower surface,
2^'-4' long and \'-^,\' wide, with prominent veins; petioles stout, pubescent, \'-\' in length;
stipules subulate from a broad triangular base, j' long. Flowers pale blue opening in July
and August, on slender hairy pedicels 5'-!' long, from the axils of large scarious caducous
bracts, in ample compound densely hoary-pubescent thyrsoid clusters 3'-4' long and
l|'-2' wide, on a leafy or naked axillary peduncle at the end of young branches. Fruit
black, j' across.

A round-headed tree, 20-25 high, with a straight trunk 6'-10' in diameter, dividing
4-5 Q from the ground into many stout spreading branches, and slender slightly angled
pale brown branchlets covered with short dense tomentum, becoming in their second season




Fig. 653

terete, nearly glabrous, roughened with scattered lenticels and marked by large elevated
leaf-scars; often a shrub. Bark of the trunk dark brown, about ' thick, and broken into
small square plates separating into thick scales.

Distribution. Santa Catalina, Santa Cruz, and Santa Rosa Islands of the Santa Barbara
group off the coast of southern California; most abundant and of its largest size on the
northern slopes of Santa Cruz;on the other islands usually shrubby, with numerous slender
stems.

2. Ceanothus thyrsiflorus Eschs. Blue Myrtle. California Like.

Leaves oblong or oblong-ovate, minutely glandular-serrate, smooth and lustrous on the
upper surface and paler and slightly pubescent on the lower surface, especially along the 3
prominent ribs, \'-\\' long and |'-1'wide; petioles stout, \'-\' in length; stipules mem-
branaceous, acute. Flowers blue or white, appearing in early spring in small pedunculate
corymbs from the axils of minute deciduous bracts, and collected into slender rather loose
thyrsoid clusters 2'-3' long in the axils of upper leaves or of small scarious bracts, and
usually surmounted by the terminal leafy shoot of the branch. Fruit ripening from July
to December, black; seeds T V long, smooth, dark brown or nearly black.

A tree, occasionally 35 high, with a trunk 12'-14' in diameter, dividing 5-6 from the



728



TREES OF NORTH AMERICA



ground into many small wide-spreading branches, and conspicuously angled pale yellow-
green branchlets slightly pubescent when they first appear, soon becoming glabrous; more
often a tall or low shrub. Bark of the trunk thin, with a bright red-brown surface separat-
ing into thin narrow appressed scales. Wood close-grained, rather soft, light brown, with
thin darker colored sap wood.

Distribution. Shady hillsides on the borders of the forest and often in the neighborhood
of streams; coast mountains of California from Mendocino Countv to the vallev of the San




Luis Rey River, San Diego County; of its largest size northward, and in the Redwood-for-
ests of the Santa Cruz Mountains; southward often a low shrub, frequently flowering on the
wind-swept shores of the ocean when only l-2 high.

3. Ceanothus spinosus Nutt. Lilac.

Leaves elliptic to oblong, full and rounded, apiculate or often slightly emarginateor grad-
ually narrowed and pointed or rarely 3-lobed at apex, and rounded or cuneate at base, when





Fig. 655



they unfold villose-pubescent below r along the stout midrib and obscure primary veins,
soon glabrous, coriaceous, usually about 1' long and \' wide; petioles stout, \'-\' in length,
at first villose, becoming nearly glabrous; leaves on vigorous shoots sometimes ovate, con-



RHAMNACE.E 7 C 29

spicuously 3-nerved, irregularly serrate with incurved apiculate teeth, or coarsely dentate,
and often 1|' long and f ' wide; stipules minute, acute. Flowers light or dark blue, very
fragrant, opening from March until May, in lax corymbs from the axils of acute pubescent
red caducous bracts on upper leafy branchlets of the year, the whole inflorescence forming
an open thyrsus often 5'-6' long and 3'-4' thick, leafless toward the apex. Fruit depressed,
obscurely lobed, crestless, black, \'-\' in diameter.

A tree, 18-20 high, with a trunk o'-6' in diameter, upright branches forming a narrow
open head, and slender divaricate angled branchlets pubescent or puberulous when they
first appear, soon glabrous, bright green, ultimately reddish brown, frequently terminating
in sharp leafless thorn-like points; more often shrubby. Bark of the trunk thin, red-brown,
roughened by small closely appressed scales.

Distribution. California, common in mountain canons near the coast of Santa Barbara,
Ventura, and Los Angeles Counties; often forming a dense undergrowth in the forest, which
it enlivens for many weeks in early spring by its large clusters of bright blue flowers.

6. COLUBRINA Brong.

Trees or shrubs, with terete branches and scaly buds. Leaves alternate, petiolate,
pinnately veined or triple-veined from the base, often ferrugineo-tomentose on the lower