TABLE OF CONTENTS
[Map of North America (exclusive of Mexico) showing the eight regions into which the country is divided according to the prevailing character of the trees] Frontispiece [Synopsis of the Families of Plants described in this work] xi [Analytical Key to the Genera of Plants described in this work, based chiefly on the character of their leaves] xvi [Manual of Trees] 1 [Gymnospermæ] 1 [Angiospermæ] 96 [Monocotyledons] 96 [Dicotyledons] 118 [Apetalæ] 118 [Petalatæ] 342 [Polypetalæ] 342 [Gamopetalæ] 790 [Glossary of Technical Terms] 893 [Index] 899
SYNOPSIS
OF THE FAMILIES OF PLANTS DESCRIBED IN THIS BOOK
Class I. GYMNOSPERMÆ.
Resinous trees; stems formed of bark, wood, or pith, and increasing in diameter by the annual addition of a layer of wood inside the bark; flowers unisexual; stamens numerous; ovules and seeds 2 or many, borne on the face of a scale, not inclosed in an ovary; embryo with 2 or more cotyledons; leaves straight-veined, without stipules.
I. Pinaceæ ([p. 1]). Flowers usually monœcious; ovules 2 or several; fruit a woody cone (in Juniperus berry-like); cotyledons 2 or many; leaves needle-shaped, linear or scale-like, persistent (deciduous in Larix and Taxodium). II. Taxaceæ ([p. 90]). Flowers diœcious, axillary, solitary; ovules 1; fruit surrounded by or inclosed in the enlarged fleshy aril-like disk of the flower; cotyledons 2; leaves linear, alternate, persistent.
Class II. ANGIOSPERMÆ.
Carpels or pistils consisting of a closed cavity containing the ovules and becoming the fruit.
Division I. MONOCOTYLEDONS.
Stems with woody fibres distributed irregularly through them, but without pith or annual layers of growth; parts of the flower in 3’s; ovary superior, 3-celled; embryo with a single cotyledon; leaves parallel-veined, persistent, without stipules.
III. Palmæ ([p. 96]). Ovule solitary; fruit baccate or drupaceous, 1 or rarely 2 or 3-seeded; leaves alternate, pinnate, flabellate or orbicular, persistent. IV. Liliaceæ ([p. 110]). Ovules numerous in each cell; fruit 3-celled, capsular or baccate; leaves linear-lanceolate.
Division II. DICOTYLEDONS.
Stems formed of bark, wood, or pith, and increasing by the addition of an annual layer of wood inside the bark; parts of the flower mostly in 4’s or 5’s; embryo with a pair of opposite cotyledons; leaves netted-veined.
Subdivision 1. Apetalæ. Flowers without a corolla and sometimes without a calyx.
Section 1. Flowers in unisexual aments (female flowers of Juglans and Quercus solitary or in spikes); ovary inferior (superior in Leitneriaceæ) when a calyx is present.
V. Salicaceæ ([p. 119]). Flowers diœcious, without a calyx. Fruit a 2—4-valved capsule. Leaves simple, alternate, with stipules, deciduous. VI. Myricaceæ ([p. 163]). Flowers monœcious or diœcious; fruit a dry drupe, covered with waxy exudations; leaves simple, alternate, resinous-punctate, persistent. VII. Leitneriaceæ ([p. 167]). Flowers diœcious, the staminate without a calyx; ovary superior; fruit a compressed oblong drupe; leaves alternate, simple, without stipules, deciduous. VIII. Juglandaceæ ([p. 168]). Flowers monœcious; fruit a nut inclosed in an indehiscent (Juglans) or 4-valved (Carya) fleshy or woody shell; leaves alternate, unequally pinnate without stipules, deciduous. IX. Betulaceæ ([p. 200]). Flowers monœcious; fruit a nut at the base of an open leaf-like involucre (Carpinus), in a sack-like involucre (Ostrya), in the axil of a scale of an ament (Betula), or of a woody strobile (Alnus); leaves alternate, simple, with stipules, deciduous. X. Fagaceæ ([p. 227]). Flowers monœcious; fruit a nut more or less inclosed in a woody often spiny involucre; leaves alternate, simple, with stipules, deciduous (in some species of Quercus and in Castanopsis and Lithocarpus persistent).
Section 2. Flowers unisexual (perfect in Ulmus); calyx regular, the stamens as many as its lobes and opposite them; ovary superior, 1-celled; seed 1.
XI. Ulmaceæ ([p. 308]). Fruit a compressed winged samara (Ulmus), a drupe (Celtis and Trema), or nut-like (Planera), leaves simple, alternate, with stipules, deciduous (persistent in Trema). XII. Moraceæ ([p. 328]). Flowers in ament-like spikes or heads; fruit drupaceous, inclosed in the thickened calyx and united into a compound fruit, oblong and succulent (Morus), large, dry and globose (Toxylon), or immersed in the fleshy receptacle of the flower (Ficus); leaves simple, alternate, with stipules, deciduous (persistent in Ficus).
Section 3. Flowers usually perfect; ovary superior or partly inferior, 1—4-celled; leaves simple, persistent in the North American species.
XIII. Olacaceæ ([p. 336]). Calyx and corolla 4—6-lobed; ovary 1—4-celled; fruit a drupe more or less inclosed in the enlarged disk of the flower; leaves alternate or fascicled, without stipules. XIV. Polygonaceæ ([p. 338]). Calyx 5-lobed; ovary 1-celled; fruit a nutlet inclosed in the thickened calyx; leaves alternate, their stipules sheathing the stems. XV. Nyctaginaceæ ([p. 340]). Calyx 5-lobed; ovary 1-celled; fruit a nutlet inclosed in the thickened calyx; leaves alternate or opposite, without stipules.
Subdivision 2. Petalatæ. Flowers with both calyx and corolla (without a corolla in Lauraceæ, in Liquidambar in Hamamelidaceæ, in Cercocarpus in Rosaceæ, in Euphorbiaceæ, in some species of Acer, in Reynosia, Condalia, and Krugiodendron in Rhamnaceæ, in Fremontia in Sterculiaceæ, in Chytraculia in Myrtaceæ, in Conocarpus in Combretaceæ and in some species of Fraxinus in Oleaceæ).
Section 1. Polypetalæ. Corolla of separate petals.
A. Ovary superior (partly inferior in Hamamelidaceæ; inferior in Malus, Sorbus, Heteromeles, Cratægus, and Amelanchier in Rosaceæ).
XVI. Magnoliaceæ ([p. 342]). Flowers perfect; sepals and petals in 3 or 4 rows of 3 each; fruit cone-like, composed of numerous cohering carpels; leaves simple, alternate, their stipules inclosing the leaf-buds, deciduous or rarely persistent. XVII. Anonaceæ ([p. 353]). Flowers perfect; sepals 3; petals 6 in 2 series; fruit a pulpy berry developed from 1 or from the union of several carpels; leaves simple, alternate, without stipules, deciduous or persistent. XVIII. Lauraceæ ([p. 356]). Flowers perfect or unisexual; corolla 0; fruit a 1-seeded drupe or berry; leaves simple, alternate, punctate, without stipules, persistent (deciduous in Sassafras). XIX. Capparidaceæ ([p. 365]). Flowers perfect; sepals and petals 4; fruit baccate, elongated, dehiscent; leaves alternate, simple, without stipules, persistent. XX. Hamamelidaceæ ([p. 366]). Flowers perfect or unisexual; sepals and petals 5 (corolla 0 in Liquidambar); ovary partly inferior; fruit a 2-celled woody capsule opening at the summit; leaves simple, alternate, with stipules, deciduous. XXI. Platanaceæ ([p. 371]). Flowers monœcious, in dense unisexual capitate heads; fruit an akene; leaves simple, alternate, with stipules, deciduous. XXII. Rosaceæ ([p. 376]). Flowers perfect; sepals and petals 5 (petals 0 in Cercocarpus); ovary inferior in Malus, Sorbus, Heteromeles, Cratægus, and Amelanchier; fruit a drupe (Prunus and Chrysobalanus), a capsule (Vauquelinia and Lyonothamnus), an akene (Cowania and Cercocarpus), or a pome (Malus, Sorbus, Heteromeles, Cratægus, and Amelanchier); leaves simple or pinnately compound, alternate (opposite in Lyonothamnus), with stipules, deciduous or persistent. XXIII. Leguminosæ ([p. 585]). Flowers perfect, regular or irregular; fruit a legume; leaves compound, or simple (Dalea), alternate, with stipules, deciduous or persistent. XXIV. Zygophyllaceæ ([p. 630]). Flowers perfect; calyx 5-lobed; petals 5; fruit capsular, becoming fleshy; leaves opposite, pinnate, with stipules, persistent. XXV. Malpigiaceæ ([p. 631]). Flowers usually perfect rarely dimorphous; calyx 5-lobed; petals 5, unguiculate; fruit a drupe or samara; leaves opposite, simple, entire, persistent; often with stipules. XXVI. Rutaceæ ([p. 633]). Flowers unisexual or perfect; fruit a capsule (Xanthoxylum), a samara (Ptelea), of indehiscent winged 1-seeded carpels (Helietta), or a drupe (Amyris); leaves alternate or opposite, compound, glandular-punctate, without stipules, persistent or rarely deciduous (0 in Canotia). XXVII. Simaroubaceæ ([p. 641]). Flowers diœcious, calyx 5-lobed; petals 5; fruit drupaceous (Simarouba), baccate (Picramnia), a samara (Alvaradoa); leaves alternate, equally pinnate, without stipules, persistent. XXVIII. Burseraceæ ([p. 645]). Flowers perfect; calyx 4 or 5-parted; petals 5; fruit a drupe; leaves alternate, compound, without stipules, deciduous. XXIX. Meliaceæ ([p. 648]). Flowers perfect; calyx 5-lobed; petals 5; fruit a 5-celled dehiscent capsule; leaves alternate, equally pinnate, without stipules, persistent. XXX. Euphorbiaceæ ([p. 649]). Flowers perfect; calyx 4—6-parted (Drypetes), 3-lobed (Hippomane), or 0 (Gymnanthes); petals 0; fruit a drupe (Drypetes and Hippomane), or a 3-lobed capsule (Gymnanthes). XXXI. Anacardiaceæ ([p. 655]). Flowers usually unisexual, diœcious or polygamo-diœcious (Pistacia without a calyx, and without a corolla in the North American species); fruit a dry drupe; leaves simple or compound, alternate, without stipules, deciduous (persistent in Pistacia and in one species of Rhus). XXXII. Cyrillaceæ ([p. 665]). Flowers perfect; calyx 5—8-lobed; petals 5—8; fruit an indehiscent capsule; leaves alternate, without stipules, persistent (more or less deciduous in Cyrilla). XXXIII. Aquifoliaceæ ([p. 668]). Flowers polygamo-diœcious; calyx 4 or 5-lobed; petals 5; fruit a drupe, with 4—8 1-seeded nutlets; leaves alternate, simple, with stipules, persistent or deciduous. XXXIV. Celastraceæ ([p. 674]). Flowers perfect, polygamous or diœcious; calyx 4 or 5-lobed; petals 4 or 5; fruit a drupe, or a capsule (Evonymus); leaves simple, opposite or alternate, with or without stipules, persistent (deciduous in Evonymus). XXXV. Aceraceæ ([p. 681]). Flowers diœcious or monœciously polygamous; calyx usually 5-parted; petals usually 5, or 0; fruit of 2 long-winged samara joined at the base; leaves opposite, simple or rarely pinnate, without or rarely with stipules, deciduous. XXXVI. Hippocastanaceæ ([p. 702]). Flowers perfect, irregular; calyx 5-lobed; petals 4 or 5, unequal; fruit a 3-celled 3-valved capsule; leaves opposite, digitately compound, long-petiolate, without stipules, deciduous. XXXVII. Sapindaceæ ([p. 711]). Flowers polygamous; calyx 4 or 5-lobed; corolla of 4 or 5 petals; fruit a berry (Sapindus and Exothea), a drupe (Hypelate), or a 3-valved capsule (Ungnadia); leaves alternate, compound, without stipules, persistent, or deciduous (Ungnadia). XXXVIII. Rhamnaceæ ([p. 718]). Flowers usually perfect; calyx 4 or 5-lobed; petals 4 or 5 (0 in Reynosia, Condalia, and Krugiodendron); fruit drupaceous; leaves simple, alternate (mostly opposite in Reynosia and Krugiodendron), with stipules, persistent (deciduous in some species of Rhamnus). XXXIX. Tiliaceæ ([p. 732]). Flowers perfect; sepals and petals 5; fruit a nut-like berry; leaves simple, alternate, mostly oblique at base, with stipules, deciduous. XL. Sterculiaceæ ([p. 749]). Flowers perfect; calyx 5-lobed; petals 0; fruit a 4 or 5-valved dehiscent capsule; leaves simple, alternate, with stipules, persistent. XLI. Theaceæ ([p. 750]). Flowers perfect; sepals and petals 5; fruit a 5-celled woody dehiscent capsule, loculicidally dehiscent; leaves simple, alternate, without stipules, persistent or deciduous. XLII. Canellaceæ ([p. 753]). Flowers perfect; sepals 3; petals 5; filaments united into a tube; fruit a berry; leaves simple, alternate, without stipules, persistent. XLIII. Kœberliniaceæ ([p. 754]). Flowers perfect; sepals and petals 4, minute; leaves bract-like, alternate, without stipules, caducous. XLIV. Caricaceæ ([p. 755]). Flowers unisexual or perfect; calyx 5-lobed; petals 5; fruit baccate; leaves palmately lobed or digitate, alternate, without stipules, persistent.
B. Ovary inferior (partly inferior in Rhizophora).
XLV. Cactaceæ ([p. 757]). Flowers perfect; petals and sepals numerous; fruit a berry; leaves usually wanting. XLVI. Rhizophoraceæ ([p. 763]). Flowers perfect; calyx 4-parted; petals 4; ovary partly inferior; fruit a 1-celled 1-seeded berry perforated at apex by the germinating embryo; leaves simple, opposite, entire, with stipules, persistent. XLVII. Combretaceæ ([p. 764]). Flowers perfect or polygamous; calyx 5-lobed; petals 5 (0 in Conocarpus); fruit drupaceous; leaves simple, alternate or opposite, without stipules, persistent. XLVIII. Myrtaceæ ([p. 768]). Flowers perfect; calyx usually 4-lobed, or reduced to a single body forming a deciduous lid to the flower (Chytraculia); petals usually 4 (0 in Chytraculia); fruit a berry; leaves simple, opposite, pellucid-punctate, without stipules, persistent. XLIX. Melastomaceæ ([p. 776]). Flowers perfect; calyx and corolla 4 or 5-lobed; stamens as many or twice as many as the lobes of the corolla; fruit capsular or baccate, inclosed in the tube of the calyx; leaves opposite, rarely verticillate, 3—9-nerved, without stipules. L. Araliaceæ ([p. 777]). Flowers perfect or polygamous; sepals and petals usually 5; fruit a drupe; leaves twice pinnate, alternate, with stipules, deciduous. LI. Nyssaceæ ([p. 779]). Flowers diœcious, polygamous, diœcious or perfect; calyx 5-toothed or lobed; petals 5 or more, imbricate in the bud, or 0; stamens as many or twice as many as the petals; fruit drupaceous (Nyssa), usually 1-celled and 1-seeded; leaves alternate, deciduous, without stipules. LII. Cornaceæ ([p. 784]). Flowers perfect or polygamo-diœcious; calyx 4 or 5-toothed; petals 4 or 5; fruit a fleshy drupe; leaves simple, opposite (alternate in one species of Cornus), without stipules, deciduous.
Section 2. Gamopetalæ. Corolla of united petals (divided in Elliottia in Ericaceæ, 0 in some species of Fraxinus in Oleaceæ).
A. Ovary superior (inferior in Vaccinium in Ericaceæ, partly inferior in Symplocaceæ and Styracaceæ).
LIII. Ericaceæ ([p. 790]). Flowers perfect; calyx and corolla 5-lobed (in Elliottia corolla of 4 petals); (ovary inferior in Vaccinium); fruit capsular, drupaceous or baccate; leaves simple, alternate, without stipules, persistent (deciduous in Elliottia and Oxydendrum). LIV. Theophrastaceæ ([p. 804]). Flowers perfect, with staminodia; sepals and petals 5; stamens 5; fruit a berry; leaves simple, opposite or alternate, entire, without stipules. LV. Myrsinaceæ ([p. 805]). Flowers perfect; calyx and corolla 5-lobed; stamens 5; fruit a drupe; leaves simple, alternate, entire, without stipules, persistent. LVI. Sapotaceæ ([p. 808]). Flowers perfect; calyx 5-lobed; corolla 5-lobed (6-lobed in Mimusops), often with as many or twice as many internal appendages borne on its throat; fruit a berry; leaves simple, alternate, without stipules, persistent (deciduous in some species of Bumelia). LVII. Ebenaceæ ([p. 820]). Flowers perfect, diœcious, or polygamous; calyx and corolla 4-lobed; fruit a 1 or several-seeded berry; leaves simple, alternate, entire, without stipules, deciduous. LVIII. Styraceæ ([p. 824]). Flowers perfect; calyx 4 or 5-toothed; corolla 4 or 5-lobed or divided nearly to the base, or rarely 6 or 7-lobed; ovary superior or partly superior; fruit a drupe; leaves simple, alternate, without stipules, deciduous; pubescence mostly scurfy or stellate. LIX. Symplocaceæ ([p. 830]). Flowers perfect; calyx and corolla 5-lobed; ovary inferior or partly inferior; fruit a drupe; leaves simple, alternate, without stipules, deciduous; pubescence simple. LX. Oleaceæ ([p. 832]). Flowers perfect or polygamo-diœcious; calyx 4-lobed (0 in some species of Fraxinus); corolla 2—6-parted (0 in some species of Fraxinus); fruit a winged samara (Fraxinus) or a fleshy drupe (Forestiera, Chionanthus and Osmanthus); leaves pinnate (Fraxinus) or simple, opposite, without stipules, deciduous (persistent in Osmanthus). LXI. Borraginaceæ ([p. 858]). Flowers perfect or polygamous; calyx and corolla 5-lobed; fruit a drupe; leaves simple, alternate, scabrous-pubescent, without stipules, persistent or tardily deciduous. LXII. Verbenaceæ ([p. 864]). Flowers perfect; calyx 5-lobed; corolla 4 or 5-lobed; fruit a drupe or a 1-seeded capsule; leaves simple, opposite, without stipules, persistent. LXIII. Solanaceæ ([p. 867]). Flowers perfect; calyx campanulate, usually 5-lobed; corolla usually 5-lobed; fruit baccate, surrounded at base by the enlarged calyx; leaves alternate, rarely opposite, without stipules. LXIV. Bignoniaceæ ([p. 868]). Flowers perfect; calyx bilabiate; corolla bilabiate, 5-lobed; fruit a woody capsule (Catalpa and Chilopsis) or a berry (Enallagma); leaves simple, opposite (sometimes alternate in Chilopsis), without stipules, deciduous (persistent in Enallagma).
B. Ovary inferior (partly superior in Sambucus in Caprifoliaceæ).
LXV. Rubiaceæ ([p. 875]). Flowers perfect; calyx and corolla 4 or 5-lobed; fruit a capsule (Exostema and Pinckneya), a drupe (Guettarda), or nut-like (Cephalanthus); leaves simple opposite, or in verticils of 3 (Cephalanthus), with stipules, persistent (deciduous in Pinckneya and Cephalanthus). LXVI. Caprifoliaceæ ([p. 882]). Flowers perfect; calyx and corolla 5-lobed; fruit a drupe; leaves unequally pinnate (Sambucus) or simple (Viburnum), opposite, without stipules, deciduous in North American species.
ANALYTICAL KEY
TO THE GENERA OF PLANTS INCLUDED IN THIS BOOK, BASED CHIEFLY ON THE CHARACTER OF THE LEAVES
I. Leaves parallel-veined, alternate, persistent, clustered at the end of the stem or branches. Monocotyledons. Stem simple; leaves stalked. Leaves fan-shaped. Leaf stalks unarmed. Rachis short; leaves usually silvery white below. Leaves 2°—4° in diameter (green below in No. 2), their segments undivided at apex.Thrinax ([p. 96]). Leaves 18′—24′ in diameter, their segments divided at apex.Coccothrinax ([p. 100]). Rachis elongated; leaves green below, their segments divided at apex.Sabal ([p. 101]). Leaf stalks armed with marginal teeth or spines. Leaf stalks furnished irregularly with broad thin large and small, straight or hooked spines confluent into a thin bright orange-colored cartilaginous margin; leaves longer than wide, divided nearly to the middle into segments parted at apex and separating on the margins into thin fibres.Washingtonia ([p. 104]). Leaf stalks furnished with stout or slender flattened teeth; leaves suborbicular, divided to the middle or nearly to the base into segments parted at apex; segments of the blade not separating on the margin into thin fibres.Acœlorraphe ([p. 105]). Leaves pinnate. Leaves 10°—12° in length, their pinnæ 2½°—3° long and often 1½° wide, deep green.Roystonea ([p. 107]). Leaves 5°—6° long, their pinnæ 18′ long and 1′ wide, dark yellow-green above, pale and glaucous below.Pseudophœnix ([p. 109]). Stem simple or branched; leaves sessile, lanceolate, long- and usually sharp-pointed at apex.Yucca ([p. 110]).
II. Leaves 1-nerved, needle-shaped, linear or scale-like, persistent (deciduous in Larix and Taxodium). Gymnospermæ.
1. Leaves Persistent.
a Leaves fascicled, needle-shaped, in 1—5-leafed clusters enclosed at base in a membranaceous sheath.Pinus ([p. 2]). aa Leaves scattered, usually linear. b Leaves linear, often obtuse or emarginate. Base of the leaves persistent on the branches. Leaves sessile, 4-sided, or flattened and stomatiferous above.Picea ([p. 34]). Leaves stalked, flattened and stomatiferous below, or angular, often appearing 2-ranked.Tsuga ([p. 42]). Base of the leaves not persistent on the branches; leaves often appearing 2-ranked. Leaves stalked, flattened, stomatiferous below; winter-buds pointed, not resinous.Pseudotsuga ([p. 47]). Leaves sessile, flattened and often grooved on the upper side, or quadrangular, rarely stomatiferous above, on upper fertile branches often crowded; winter-buds obtuse, resinous (except in No. 9).Abies ([p. 50]). bb Leaves linear-lanceolate, rigid, acuminate, spirally disposed, appearing 2-ranked by a twist in the petiole. Leaves abruptly contracted at base, long-pointed, with pale bands of stomata on the lower surface on each side of the midveins; fruit drupe-like.Torreya ([p. 91]). Leaves gradually narrowed at base, short-pointed, paler, and without distinct bands of stomata on the lower surface; fruit berry-like.Taxus ([p. 93]). bbb Leaves ovate-lanceolate and scale-like, spreading in 2 ranks or linear on the same tree, acute, compressed, keeled on the back and closely appressed or spreading at apex.Sequoia ([p. 61]). aaa Leaves opposite or whorled, usually scale-like.
Internodes distinctly longer than broad; branchlets flattened, of nearly equal color on both sides; leaves eglandular.Libocedrus ([p. 65]). Internodes about as long as broad, often pale below, usually glandular. Branchlets flattened. Branchlets in one plane, much flattened, 1/12′—⅙′ broad.Thuya ([p. 67]). Branchlets slightly flattened, 1/24′—1/16′ broad.Chamæcyparis ([p. 75]). Branchlets terete or 4-angled. Branchlets more or less in one plane; fruit a cone.Cupressus ([p. 69]). Branchlets not in one plane; fruit a berry (leaves needle-shaped, in whorls of 3 in No. 1).Juniperus ([p. 78]).
2. Leaves Deciduous.
Leaves in many-leafed clusters on short lateral spurs.Larix ([p. 31]). Leaves spreading in 2 ranks.Taxodium ([p. 63]).
III. Leaves netted-veined, rarely scale-like or wanting. Dicotyledons.
A. LEAVES OPPOSITE. (B, see [p. xix]).
1. Leaves Simple. (2, see [p. xviii]).
Leaves persistent.
a Leaves with stipules. b Leaves entire or occasionally slightly crenate or serrate. c Leaves emarginate at apex, very short-stalked, 1½′—2′ long. Leaves obovate, gradually narrowed into the petiole.Gyminda ([p. 678]). Leaves oval to oblong, rounded or broad-cuneate (rarely alternate). Branchlets densely velutinous.Krugiodendron ([p. 721]). Branchlets slightly puberulous at first, soon glabrous.Reynosia ([p. 720]). cc Leaves not emarginate at apex. Leaves obtuse, rarely acutish or abruptly short-pointed. Leaves elliptic, 3½′—5′ long.Rhizophora ([p. 763]). Leaves obovate, usually rounded at apex, ¾′—2′ long.Byrsonima ([p. 632]). Leaves acute to acuminate. Leaves oblong-ovate to lanceolate; branchlets glabrous.Exostema ([p. 877]). Leaves broad-elliptic to oblong-elliptic; branchlets villose.Guettarda ([p. 879]). bb Leaves serrate (often pinnate).Lyonothamnus ([p. 378]). aa Leaves without stipules. Petioles biglandular; leaves obtuse or emarginate, 1½′—2½′ long.Laguncularia ([p. 767]). Petioles without glands. Leaves furnished below with small dark glands, slightly aromatic; petioles short. Leaves oblong to oblong-ovate and acuminate or elliptic and bluntly short-pointed.Calyptranthes ([p. 769]). Leaves ovate, obovate or elliptic.Eugenia ([p. 770]). Leaves without glands. Leaves green and glabrous below. Leaves obtuse or emarginate at apex (rarely alternate), 1′—1½′ long.Torrubia ([p. 341]). Leaves acute, acuminate, or sometimes rounded or emarginate, 3′—5′ long. Leaves distinctly veined.Citharexylon ([p. 864]). Leaves obscurely veined.Osmanthus ([p. 856]). Leaves hoary tomentulose or scurfy below. Leaves strongly 3-nerved, acuminate, densely scurfy below.Tetrazygia ([p. 776]). Leaves penniveined, rounded or acute at apex, hoary tomentulose below.Avicennia ([p. 865]).
** Leaves deciduous. a Leaves without lobes. b Leaves serrate. Winter-buds with several opposite outer scales. Leaves puberulous below, closely and finely serrate; axillary buds solitary.Evonymus ([p. 675]). Leaves glabrous below, remotely crenate-serrulate; axillary buds several, superposed.Forestiera ([p. 853]). Winter-buds enclosed in 2 large opposite scales.Viburnum ([p. 886]). bb Leaves entire. c Leaves without stipules. Leaves suborbicular or elliptic to oblong. Leaves rounded or acutish at apex, 1′—2′ long, occasionally 3-foliolate, glabrous; branchlets quadrangular.Fraxinus anomala ([p. 837]). Leaves acuminate or acute at apex, 3′—4′ long. Leaf-scars connected by a transverse line, with 3 bundle-traces; branchlets slender, appressed-pubescent.Cornus ([p. 785]). Leaf-scars not connected, with 1 bundle-trace; branchlets stout, villose, puberulous or glabrous.Chionanthus ([p. 855]). Leaves broad-ovate, cordate, acuminate, 5′—12′ long, on long petioles.Catalpa ([p. 870]). Leaves linear to linear-lanceolate, short-stalked or sessile (sometimes alternate).Chilopsis ([p. 869]). cc Leaves with persistent stipules, entire. Leaves oval or ovate; winter-buds resinous, the terminal up to ½′ in length.Pinckneya ([p. 876]). Leaves ovate to lanceolate; winter-buds minute.Cephalanthus ([p. 878]). aa Leaves palmately lobed.Acer ([p. 681]).
2. Leaves Compound.
a Leaves persistent, with stipules. Leaves equally pinnate; leaflets entire.Guaiacum ([p. 630]). Leaves unequally pinnately parted into 3—8 linear-lanceolate segments (sometimes entire).Lyonothamnus ([p. 378]). Leaves trifoliate. Leaflets stalked.Amyris ([p. 640]). Leaflets sessile.Helietta ([p. 637]). aa Leaves deciduous. Leaves unequally pinnate or trifoliate. Leaflets crenate-serrate or entire, the veins arching within the margins; stipules wanting; winter-buds with several opposite scales.Fraxinus ([p. 833]). Leaflets sharply or incisely serrate, the primary veins extending to the teeth. Leaflets 3—7, incisely serrate; stipules present; winter-buds with 1 pair of obtuse outer scales.Acer Negundo ([p. 699]). Leaflets 5—9, sharply serrate; stipules present; winter-buds with many opposite acute scales; pith thick.Sambucus ([p. 882]). Leaves digitate, with 5—7, sharply serrate leaflets; terminal buds large.Æsculus ([p. 702]).
B. LEAVES ALTERNATE.
1. Leaves Simple. (2, see [p. xxiv]).
* Leaves persistent. (** see [p. xxii]).
a Leaves deeply 3—5-lobed, ⅓′—½′ long, with linear lobes, hoary tomentose below.Cowania ([p. 549]). aa Leaves palmately lobed. Leaves stellate-pubescent, about 1½′ in diameter, with stipules.Fremontia ([p. 749]). Leaves glabrous, 1°—2° in diameter, without stipules.Carica ([p. 755]). aaa Leaves not lobed or pinnately lobed. b Branches spinescent. Leaves clustered at the end of the branches, at least 2′—3′ long.Bucida ([p. 765]). Leaves fascicled on lateral branchlets, obtuse or emarginate, pale and glabrous beneath.Bumelia angustifolia ([p. 816]). Leaves scattered. Leaves generally obovate, mucronate, not more than ½′—1′ long, glabrous and green or brownish tomentulose beneath.Condalia ([p. 719]). Leaves elliptic-ovate to oblong, obtuse or emarginate, glabrous, 1—2 cm. long.Ximenia ([p. 337]). bb Branches not spinescent. c Leaves serrate, or lobed (in some species of Quercus). (cc, see [p. xxii]). d Juice watery. (dd, see [p. xxii]). e Stipules present. (ee, see [p. xxii]). f Primary veins extending straight to the teeth. Leaves and branchlets glabrous or pubescent to tomentose with fascicled hairs. Leaves fulvous-tomentose beneath, repand-dentate, 3′—5′ long.Lithocarpus ([p. 236]). Leaves glabrous or grayish to whitish tomentose beneath, entire, lobed or dentate.Quercus sp. 21—34 ([p. 268]). Leaves and branchlets coated with simpled silky or woolly hairs at least while young, not more than 2½′ long.Cercocarpus ([p. 550]). ff Primary veins arching and united within the margin. Leaves 3-nerved from the base.Ceanothus ([p. 726]). Leaves not 3-nerved. Leaves acute. Leaves sinuately dentate, with few spiny teeth (rarely entire), glabrous.Ilex opaca ([p. 669]). Leaves serrate. Leaves tomentose below; branchlets tomentose. Leaves narrow-lanceolate, glabrous and smooth above.Vauquelinia ([p. 377]). Leaves ovate, cordate, scabrate above.Trema ([p. 327]). Leaves glabrous below.Heteromeles ([p. 392]). Leaves entire, very rarely toothed. Leaves elliptic, glabrous.Prunus caroliniana ([p. 579]). Leaves oblanceolate, pubescent beneath when young.Ilex Cassine ([p. 670]). Leaves obtuse, sometimes mucronate. Leaves spinose-serrate, glabrous. Leaves broad-ovate to suborbicular or elliptic; branchlets dark red-brown, spinescent.Rhamnus crocea ([p. 723]). Leaves ovate to ovate-lanceolate; branchlets yellow or orange-colored, not spinescent.Prunus ilicifolia ([p. 581]). Leaves crenate (often entire), oval to oblong.Ilex vomitoria ([p. 671]). ee Stipules wanting. Leaves resinous-dotted, aromatic, 1½′—4′ long.Myrica ([p. 163]). Leaves not resinous-dotted, crenately serrate, 4′—6′ long. Leaves dark green, glabrous below.Gordonia Lasianthus ([p. 751]). Leaves yellowish green, pubescent below, sometimes nearly entire.Symplocos ([p. 831]). dd Juice milky. Petioles 2½′—4′ long; leaves broad-ovate.Hippomane ([p. 652]). Petioles about ¼′ long; leaves elliptic to oblong-lanceolate.Gymnanthes ([p. 654]). cc Leaves entire (rarely sparingly toothed on vigorous branchlets). d Stipules present. e Stipules connate, at least at first. Stipules persistent, forming a sheath surrounding the branch above the node; leaves obtuse.Coccolobis ([p. 338]). Stipules deciduous, enveloping the unfolded leaf. Leaves ferrugineous-tomentose beneath.Magnolia grandiflora ([p. 345]). Leaves glabrous beneath, with milky juice.Ficus ([p. 333]). ee Stipules free. f Juice milky; leaves oval to oblong, 3′—5′ long.Drypetes ([p. 650]). ff Juice watery. g Leaves obtuse or emarginate at apex. Leaves with ferrugineous scales beneath, their petioles slender.Capparis ([p. 365]). Leaves without ferrugineous scales. Leaves soft-pubescent on both sides.Colubrina cubensis ([p. 730]). Leaves glabrous at least at maturity. Leaves rarely 2′—3′ long, standing on the branch at acute angles.Chrysobalanus ([p. 583]). Leaves rarely more than 1′ long, spreading (sometimes 3-nerved).Ceanothus spinosos ([p. 728]). gg Leaves acute or acutish.
Petioles with 2 glands.Conocarpus ([p. 766]). Petioles without glands. Leaves and branchlets more or less pubescent, at least while young. Leaves fascicled except on vigorous branchlets.Cercocarpus ([p. 550]). Leaves not fascicled. Winter-buds minute, with few pointed scales. Leaves rounded or nearly rounded at base.Colubrina sp. 1, 3 ([p. 729]). Leaves broad-cuneate at base.Ilex Cassine ([p. 670]). Winter-buds conspicuous, with numerous scales. Leaves usually lanceolate, entire, covered below with yellow scales.Castanopsis ([p. 234]). Leaves oblong or oblong-obovate, repand-dentate, fibrous tomentose below.Lithocarpus ([p. 236]). Leaves and branchlets glabrous. Leaf-scar with 1 bundle-trace.Ilex Krugiana ([p. 672]). Leaf-scar with 3 bundle-traces. Cherry Laurels.Prunus sp. 19—22 ([p. 579]). dd Stipules wanting. e Leaves aromatic when bruised. Leaves resinous-dotted.Myrica ([p. 163]). Leaves not resinous-dotted. Leaves obtuse, obovate, glabrous.Canella ([p. 753]). Leaves acute. Leaves mostly rounded at the narrowed base, ovate to oblong, acute, glabrous.Anona ([p. 354]). Leaves more or less cuneate at base, elliptic to lanceolate, usually acuminate. Leaves abruptly long-acuminate, glabrous, the margin undulate; branchlets red-brown.Misanteca ([p. 364]). Leaves gradually acuminate or nearly acute. Leaves strongly reticulate beneath. Branchlets glabrous, light grayish brown; leaves glabrous, light green beneath.Ocotea ([p. 359]). Branchlets pubescent while young, greenish or yellowish; leaves pale beneath, pubescent while young.Umbellularia ([p. 360]). Leaves not or slightly reticulate, glaucous, glabrous or pubescent beneath.Persea ([p. 356]).
ee Leaves not aromatic. f Leaves acute or acutish. Leaves obovate, gradually narrowed into short petioles. Leaves 2′—2½′ long.Schæfferia ([p. 679]). Leaves at least 6′—8′ long.Enallagma ([p. 873]). Leaves elliptic to oblong or ovate. Leaves rough or pubescent above, pubescent below, subcordate to cuneate at base. Leaves stellate-pubescent.Solanum ([p. 867]). Leaves scabrous above. Petiole ⅛′—¼′ long; leaves oval or oblong, 1¼′—4′ long.Ehretia ([p. 862]). Petiole 1′—1½′ long; leaves ovate to oblong-ovate, 3′—7′ long.Cordia ([p. 858]). Leaves smooth above. Winter-buds scaly. Leaves covered below with ferrugineous or pale scales, 1′—3′ long.Lyonia ([p. 797]). Leaves glabrous or nearly so below. Leaves ovate-lanceolate or obovate-lanceolate, 4′—12′ long, usually clustered at end of branchlet, veinlets below obscure.Rhododendron ([p. 792]). Leaves elliptic or oval to oblong or lanceolate. Leaves light yellowish green below and without distinctly visible veins or veinlets, entire, 3′—4′ long.Kalmia ([p. 794]). Leaves pale below and more or less distinctly reticulate, occasionally serrate or denticulate, 1′—5′ long; bark of branches red.Arbutus ([p. 799]). Winter-buds naked. Leaves pubescent below when unfolding. Mature leaves nearly glabrous below. Leaves oblong-lanceolate to narrow-obovate.Dipholis ([p. 810]). Leaves oval.Sideroxylum ([p. 809]). Mature leaves covered below with brilliant copper-colored pubescence. Leaves glabrous below.Chrysophyllum ([p. 817]). Leaves marked by minute black dots, ovate to oblong-lanceolate.Ardisia ([p. 806]). Leaves lepidote, oblong-obovate.Rapanea ([p. 807]). ff Leaves obtuse or emarginate at apex. g Leaves rounded or cordate at base, emarginate, their petioles slender. Leaves reniform to broad-ovate, cordate; juice watery.Cercis ([p. 603]). Leaves elliptic to oblong, rounded at base; juice milky or viscid. Leaves emarginate; petioles slender, rufous-tomentulose.Mimusops ([p. 819]). Leaves obtuse at apex; petioles stout, grayish-tomentulose or glabrous.Rhus integrifolia ([p. 664]). gg Leaves cuneate at base.
Petioles slender, ½′ long.Beureria ([p. 861]). Petioles short and stout. Leaves coriaceous, with thick revolute margins (sometimes opposite).Jacquinia ([p. 804]). Leaves subcoriaceous, slightly revolute. Leaves reticulate-veined beneath. Leaves oval to obovate or oblong-oval, more or less pubescent while young.Vaccinium ([p. 802]). Leaves oblong to oblong-obovate, glabrous.Cyrilla ([p. 666]). Leaves obscurely veined beneath, glabrous. Leaves oblong-lanceolate, narrowed toward the emarginate apex, decurrent nearly to base of petiole.Cliftonia ([p. 667]). Leaves rounded at apex, distinctly petioled.Maytenus ([p. 676]).
** Leaves deciduous.
† Leaves conspicuous. (††, see [p. xxiv].)
a Leaves entire, sometimes 3 or 4-lobed. (aa, see [p. xxiii]). b Stipules present. Juice milky.Maclura ([p. 331]). Juice watery. Stipules connate, enveloping the young leaves, their scars encircling the branchlet. Leaves acute or acuminate, entire; winter-buds pointed, nearly terete.Magnolia ([p. 342]). Leaves truncate, sinuately 4-lobed; winter-buds obtuse, compressed.Liriodendron ([p. 351]). Stipules distinct. Branches spinescent; leaves glandular, caducous (crenately serrate on vigorous shoots).Dalea ([p. 621]). Branches not spinescent; leaves without glands. Winter-buds with a single pair of connate scales.Salix ([p. 138]). Winter-buds with several pairs of imbricate scales. Branchlets without a terminal bud; leaves 3-nerved.Celtis ([p. 318]). Branchlets with a terminal bud, leaves penniveined.Quercus sp. 17—20 ([p. 262]). bb Stipules wanting. c Branchlets bright green and lustrous for the first 2 or 3 years; leaves sometimes 3-lobed, aromatic.Sassafras ([p. 362]). cc Branchlets brown or gray. d Leaves acute or acuminate. Leaves 10′—12′ long, obovate-oblong, acuminate, glabrous, emitting a disagreeable odor.Asimina ([p. 353]). Leaves smaller. Petioles very slender, 1′—2′ long; leaves elliptic, acuminate.Cornus alternifolia ([p. 789]). Petioles short. Branchlets with a terminal bud. Leaf-scars about as long as broad; branchlets without lenticels, light reddish brown.Elliottia ([p. 791]). Leaf-scars crescent-shaped, broader than long, with 3 distinct bundle-traces. Leaves pubescent on both sides, rugulose above; petioles 1′—2′ long, like the young branchlet densely pubescent.Leitneria ([p. 167]). Leaves glabrous and smooth above, glabrous or pubescent below; petioles and branchlets usually glabrous or nearly so at maturity.Nyssa ([p. 779]). Branchlets without a terminal bud. Pubescence consisting of simple hairs or wanting. Leaves 4′—6′ long, pubescent beneath while young; branchlet light brown or gray.Diospyros virginiana ([p. 821]). Leaves 1½′—3′ long, glabrous; branches light yellowish gray.Schœpfia ([p. 336]). Pubescence stellate; leaves obovate or elliptic, 2½′—5′ long, pubescent below.Styrax ([p. 829]). dd Leaves obtuse or acute. Branchlets not spinescent. Leaves glabrous at maturity, their petioles slender.Cotinus ([p. 657]). Leaves pubescent below at maturity; their petioles short and thick.Diospyros texana ([p. 823]). Branchlets spinescent; leaves often fascicled on lateral branchlets.Bumelia ([p. 812]). aa Leaves serrate or pinnately lobed. b Stipules present. (bb, see [p. xxvi].) c Winter-buds naked. Leaves oblique at base, the upper side rounded or subcordate, obovate, coarsely toothed.Hamamelis ([p. 368]). Leaves equal at base, cuneate, finely serrate or crenate.Rhamnus sp. 2, 3 (p. [724], [725]). cc Winter-buds with a single pair of connate scales. Primary veins arching and uniting within the margins; leaves simply serrate or crenate, sometimes entire.Salix ([p. 138]). Primary veins extending to the teeth, leaves doubly serrate, often slightly lobed.Alnus ([p. 220]). ccc Winter-buds with several pairs of imbricate scales. d Terminal buds wanting; branchlets prolonged by an upper axillary bud. Juice milky; leaves usually ovate, often lobed.Morus ([p. 328]). Juice watery; leaves not lobed. Leaves distinctly oblique at base. Leaves with numerous prominent lateral veins. Leaves generally broad-ovate, simply serrate, stellate-pubescent at least while young, rarely glabrous.Tilia ([p. 732]). Leaves never broad-ovate, usually doubly serrate, more or less pubescent with simple hairs, at least while young. Winter-buds ovoid, usually acute, ⅓ to nearly as long as petioles; leaves 1′—7′ long, doubly serrate.Ulmus ([p. 309]). Winter-buds subglobose, minute; leaves 2′—2½′ long, crenate-serrate.Planera ([p. 316]). Leaves 3 or 4-nerved from the base.Celtis ([p. 318]). Leaves slightly or not at all oblique at base. Leaves 3-nerved from the base, glandular-crenate or glandular-serrate.Ceanothus ([p. 726]). Leaves not or obscurely 3-nerved at base, usually doubly serrate. Leaves blue-green; petioles ¼′—½′ long; bark smooth, gray-brown.Carpinus ([p. 201]). Leaves yellow-green. Bark rough, furrowed; petioles ⅛′—¼′ long; leaves not resinous-glandular.Ostrya ([p. 202]). Bark flaky or cherry-tree like; petioles ¼′—1′ long; leaves often resinous-glandular while young.Betula ([p. 205]). dd Terminal buds present. Primary veins arching and uniting within the margin (extending to the margin in the lobed leaves of Malus). Winter-buds resinous; leaves crenate, usually truncate at base; petioles slender.Populus ([p. 119]). Winter-buds not resinous. Leaf-scars with 3 bundle-traces. Leaves involute in bud, often lobed on vigorous shoots; winter-buds obtuse, short, pubescent.Malus ([p. 379]). Leaves conduplicate (or in some species of Prunus convolute), never lobed; winter-buds acute. Winter-buds elongated; branches never spinescent.Amelanchier ([p. 393]). Winter-buds not elongated, ovoid; branches sometimes spinescent.Prunus ([p. 555]). Leaf-scars with 1 bundle-trace; leaves simply serrate.Ilex sp. 5—6 ([p. 673]).
Primary veins extending to the teeth or to the lobes. Leaves lobed.Quercus sp. 1—16, 35—50 (p. [241], [283]). Leaves serrate-toothed. Winter-buds with numerous scales. Leaves lustrous beneath, remotely serrate or denticulate; winter-buds elongated, acuminate.Fagus ([p. 228]). Leaves pale beneath, coarsely dentate or serrate; winter-buds acute. Chestnut Oaks.Quercus sp. 51—54 ([p. 303]). Winter-buds with 2 pairs of scales.Castanea ([p. 230]). Leaves doubly or simply serrate, or lobed, with serrate lobes; branches often furnished with spines. Leaves involute in the bud; branchlets often ending in blunt spines.Malus ([p. 379]). Leaves conduplicate in the bud; branches usually armed with sharp-pointed single or branched axillary spines.Cratægus ([p. 397]). bb Stipules wanting. c Leaves not lobed. Leaves subcoriaceous, oblong, sometimes nearly entire, glabrous.Symplocos ([p. 831]). Leaves thin. Leaves oblong-obovate, acute, pubescent beneath.Gordonia alatamaha ([p. 752]). Leaves oblong or lanceolate, acuminate, glabrous or puberulous while young, turning scarlet in the autumn.Oxydendrum ([p. 796]). Leaves ovate to elliptic, stellate-pubescent or glabrous, turning yellow in the autumn.Halesia ([p. 824]). cc Leaves palmately lobed. Stipules large, foliaceous, united; branchlets without a terminal bud.Platanus ([p. 371]). Stipules small, free, caducous; branchlets with a terminal bud.Liquidambar ([p. 367]).
†† Leaves inconspicuous or wanting; branches spiny or prickly.
Branches or stems succulent, armed with numerous prickles. Branches and stems columnar, ribbed, continuous; leaves 0.Cereus ([p. 757]). Branches jointed, tuberculate; leaves scale-like.Opuntia ([p. 759]). Branches rigid, spinescent. Leaves minute, narrow-obovate. Branchlets bright green.Kœberlinia ([p. 754]). Branchlets red-brown.Dalea ([p. 621]). Leaves scale-like, caducous.Canotia ([p. 677]).
2. Leaves compound.
* Leaves 3-foliolate, without stipules.
Leaves persistent; leaflets obovate, entire, sessile.Hypelate ([p. 716]). Leaves deciduous. Leaflets deltoid to hastate, entire, rounded at apex; branches prickly.Erythrina ([p. 627]). Leaflets ovate to oblong, acuminate, strongly scented and bitter; branches unarmed.Ptelea ([p. 639]).
** Leaves twice pinnate; stipules present.
a Leaves unequally twice pinnate, 2°—4° long, deciduous; leaflets serrate, 2′—3′ in length; branches and stem armed with scattered prickles.Aralia ([p. 778]). aa Leaves equally twice pinnate, usually smaller; branches unarmed or armed with stipular or axillary spines (in Parkinsonia often apparently simply pinnate). b Leaflets crenate; leaves simply or twice-pinnate on the same plant, deciduous, usually armed with simple or branched axillary spines.Gleditsia ([p. 607]). bb Leaflets entire. Leaflets 2—2½′ long; leaves deciduous; branchlets stout, unarmed.Gymnocladus ([p. 605]). Leaflets smaller; leaves usually persistent; branchlets slender. Branches armed with prickles or spines. Leaves with 2 or rarely 4 pinnæ. Branches armed with axillary spines or spiny rachises. Pinnæ with 4—8 leaflets; branches with short axillary spines.Cercidium ([p. 613]). Pinnæ with 8—60 leaflets; branches armed with spiny rachises or rigid branchlets terminating in stout spines.Parkinsonia ([p. 611]). Branches armed with stipular prickles; leaves persistent. Pinnæ with many oblong to linear leaflets.Prosopis ([p. 599]). Pinnæ with 1 pair of orbicular to broad-oblong leaflets.Pithecolobium unguis-cati ([p. 586]). Leaves with 6, or more, rarely 4, pinnæ. Prickles usually spreading, often recurved.Acacia ([p. 591]). Prickles usually more or less ascending, straight.Pithecolobium ([p. 586]). Branches unarmed. Branchlets and petioles glabrous; leaves with 2—5 pair of pinnæ, each with 40—80 leaflets.Lysiloma ([p. 589]). Branchlets and petioles pubescent while young; leaves with 5—17 pair of many-foliolate pinnæ, or pinnæ 2—4 and each with 8—16 leaflets.Leucæna ([p. 596]).
*** Leaves simply pinnate.
a Leaves equally pinnate. Stipules wanting. Leaflets 2—4, generally oblong-obovate.Exothea ([p. 714]). Leaflets 6—12. Leaflets obtuse, usually oblong-obovate. Leaflets 8—12, 2′—3′ long, pale below; leaves occasionally opposite.Simarouba ([p. 642]). Leaflets 6—8, 1′—1½′ long, green below.Xanthoxylum coriaceum ([p. 637]). Leaflets 6—8, acuminate.Swietenia ([p. 648]). Stipules present. Branches armed with infra-stipular spines in pairs; leaflets 10—15, usually oblong-obovate, ½′—¾′ long, persistent.Olneya ([p. 626]). Branches unarmed; leaflets 20—46, ovals ½′—⅔′ long.Eysenhardtia ([p. 620]). aa Leaves unequally pinnate. b Stipules present. Leaflets sharply serrate; leaves deciduous; winter-buds resinous.Sorbus ([p. 390]). Leaflets entire or crenately serrate. Leaves deciduous. Leaflets 7—11, 3′—4½′ long; branches unarmed. Leaflets usually alternate, thin and glabrous at maturity.Cladrastis ([p. 618]). Leaflets opposite, coriaceous, pubescent beneath at least along the veins.Ichthyomethia ([p. 628]). Leaflets 9—21, 1—2 cm. long. Branches usually with stipular prickles, sometimes viscid.Robinia ([p. 622]). Branches unarmed, not viscid; leaflets 13—19, elliptic.Sophora affinis ([p. 617]). Leaves persistent. Leaflets 7—9, oblong-elliptic, 1′—2½′ long; branches unarmed.Sophora secundiflora ([p. 616]). Leaflets 10—15; branches prickly.Olneya ([p. 626]). bb Stipules wanting. d Leaves persistent. Leaflets long-stalked (sometimes nearly sessile in Xanthoxylum flavum). Leaflets oblong-ovate, cuneate at base. Leaflets acuminate, glabrous.Picramnia ([p. 643]). Leaflets obtuse, tomentose when unfolding.Xanthoxylum flavum ([p. 636]). Leaflets broad-ovate, usually rounded or subcordate at base.Metopium ([p. 658]). Leaflets sessile or nearly so. Petiole and rachis winged. Leaflets crenate, obovate, about ½′ long; branches prickly.Xanthoxylum Fagara ([p. 634]). Leaflets entire. Leaflets oblong, usually acute, 3′—4′ long.Sapindus saponaria ([p. 712]). Leaflets spathulate, rounded at apex, not more than ¾′ long.Pistacia ([p. 656]). Petiole and rachis not winged. Leaflets 7—19, acuminate, 2′—5′ long.Sapindus marginatus ([p. 713]). Leaflets 21—41, obtuse, ½′—¾′ long.Alvaradoa ([p. 644]). dd Leaves deciduous. Leaflets long-stalked, 3—7, entire, acute.Bursera ([p. 645]). Leaflets sessile or nearly so. Branches prickly; leaflets crenate.Xanthoxylum clava-Herculis ([p. 635]). Branches unarmed. Juice milky or viscid; leaflets serrate or entire; rachis sometimes winged.Rhus species 1—3 ([p. 660]). Juice watery. Rachis without wings. Leaflets entire, acuminate, 7—9.Sapindus Drummondii ([p. 714]). Leaflets serrate or crenate. Winter-buds large; leaflets 5—23, aromatic. Winter-buds naked.Juglans ([p. 169]). Winter-buds covered with scales.Carya ([p. 176]). Winter-buds minute, globose, scaly; leaflets 5—7, ovate, not aromatic.Ungnadia ([p. 717]). Rachis winged; leaflets 10—20, entire, rounded at apex, not more than ¼′ long.Bursera microphylla ([p. 647]).