The NCSU Libraries
North Carolina State University

This book was presented by

Kenneth W. Winston,
Sr.

N I Hill! I AR0UNA STAT- UN,VERS,TY LIBRARIES

S02569159 .

This book is due on the date indicated unless
recalled by the Libraries. Books not returned on
time are subject to replacement charges.
Borrowers may access their library accounts at:
http://www.Iib.ncsu.edu/ads/borrow.html

INTRODUCTION

TO

STRUCTURAL AND SYSTEMATIC

BOTANY,

AND VEGETABLE PHYSIOLOGY,

BEING

A FIFTH AND REVISED EDITION

OF

THE BOTANICAL TEXT-BOOK,

ILLUSTRATED WITH OVER THIRTEEN HUNDRED WOODCUTS.

By ASA GRAY, M.D.,

USHER PROFESSOR OF NATURAL HISTORY IN HARVARD UNIVERSITY.

IVISON, BLAKEMAN, TAYLOR & CO.,

NEW YORK AND CHICAGO.

1877.

Entered according to Act of Congress, in the 3-ear 1857. by

IVISON AND rHINNisV,

in the Clerk's Office of the District Court for the Southern District of New York.

PREFACE

This compendious treatise is designed to furnish classes
in the higher seminaries of learning, colleges, and medi-
cal schools, as well as private students generally, with a
suitable text-book of Structural and Physiological Botany,
and a convenient introduction to Systematic or Descriptive
Botany, adapted to the present condition of the science.
The favor with which the former editions have been re-
ceived, while it has satisfied the author that the plan of the
work is well adapted to the end in view, has made him the
more desirous to improve its execution, and to render it a
better exponent of the present state of Botany. In this
view, the structural and physiological part of the work, and
the chapters on the Principles of Classification and of the
Natural System, have been again almost entirely rewritten,
and such changes made as the advanced state of our knowl-
edge required, or the author's continued experience in
teaching has suggested. This has been done without in-
creasing the extent of this part of the volume, which, con-
sidering the limited time devoted to the study in our col-
leges, &c, is found to be as full as is desirable for a text-
book. Being intended as a manual for instruction merely,
the Illustrations of the Natural Orders, which form the prin-
cipal portion of the systematic part of the work, arc brief

IV PREFACE.

and general. Such a sketch, however amplified, could never
take the place of a Flora, or System of Plants, but is de-
signed merely to give a general idea of the distribution of
the vegetable kingdom into families, &c, with a cursory no-
tice of their structure, properties, and principal useful pro-
ducts. In applying the principles of classification, and his
knowledge of the structure of plants, to the investigation of
the plants that grow spontaneously around him, the student
will necessarily use some local Flora, such, for example, as
the author's Manual of the Botany of the Northern United
States. For particular illustrations the botanist may ad-
vantageously consult the author's Genera of the Plants of
the United Stales illustrated by Figures and Analyses from
Nature, of which two volumes have been published.

About twenty-four of the wood-cuts are, by permission,
selected from original sketches made for a Report on the
Trees of the United States, in preparation by the author for
the Smithsonian Institution. The numerous figures added
to this edition are wholly of an original character.

The numerals enclosed in parentheses, which abound in
the pages of this work, are references to other and mostly
earlier paragraphs, in which the subjects or the terms in
question are treated of or explained.

A full Glossary or Dictionary of Botanical Terms (com-
bined with an Index) is added to the volume. In this, it
is thought, the student will find explanations of all the
technical botanical terms he is likely to meet with in descrip-
tive works, written in the English language. The words
are here accentuated, in all cases where this seemed to bo
needful.

Harvard University, Cambridge, Sept. 1857.

CONTEN T S.

Paqb

INTRODUCTION. — General View of tiie Science . . 13
PAET I.

STRUCTURAL AND PHYSIOLOGICAL BOTANY.

CHAPTER I. — OF THE ELEMENTARY STRUCTURE OF

PLANTS

17

Sect. I. Of Organization in General . . . .17

The Elementary Constitution of Plants . . . • 17

Their Organic Constitution . . » • • • .18

Distinctions between Minerals and Organized Beings 1 9
Individuals and Species ...»>•• 20

Life 21

Difference between Vegetables and Animals • . .21

Sect. II. Of the Cells and Cellular Tissue of Plants 22

Cellular Structure 23

The Cell as a Living Organism 26

Its Formation and Growth 27

Original Cell- Formation 27

Cell-Multiplication 28

Free Cell-Multiplication within a Mother-Cell . .30

Cell-Growth . 30

Branching Cells 31

Cyclosis or Circulation in Cells . • • • • • 3l
1*

VI CONTKNTS.

Transference of Fluid from Cell to Cell • . . . .33

Increase of Cell-Walls in Thickness 34

Markings of the Walls of Cells 36

Dots or Pits 37

Disks of Coniferous Wood 38

Bands, Kings, or Spiral Markings ..... 39

Gelatinous Coils 40

Sect. III. Of the Kinds oh Transformations of Cellu-
lar Tissue, viz. Woody Tissue, Ducts, etc. 40

Parenchyma 41

Prosenchyma, Woody Tissue 41

Bast Tissue 44

Vascular Tissue or Vessels, Dotted Ducts, &c. . . .45

Interlaced Fibrilliform Tissue 48

Laticiferous Tissue 49

Intercellular System , 50

Epidermal System 51

Sect. IV. Of the Contents of Cells . . .52

Sap, Sugar . 53

Starch 54

Amyloid .......... 55

Oils, Wax, Vegetable Acids 56

Essential Oils, Tannin, Alkaloids . . . . . .57

Chlorophyll 58

Earthy Incrustations' 58

Crystals or Raphides, Cystolithes 59

CHAPTER II. — OF THE GENERAL DEVELOPMENT AND

MORPHOLOGY OF PLANTS CO

Sect. I. Plants of the Lower Grade; their Develop-
ment from the Cell 61

Plants of a Single Cell CI

Plants of a Single Row of Cells 65

Plants of a Single Plane or Layer of Cells . . . . G6

Plants of a Solid Tissue of Cells 67

Plants with a Distinct Axis and Foliage • . . . .67

Cellular and Vascular Plants ...... 68

Flowerless or Cryptogamous Plants . . . . .69

CONTENTS. Vii

Sect. II. Plants of the Higher Grade ; their Devklop-

MENT FROM THE SEED ..... C9

Flowering or Phaenogamous Plants G9

Organs of Vegetation and of Reproduction ... 70

The Seed 70

The Development of the Embryo in Germination . . 71

Number of Cotyledons ....... 78

CHAPTER III. — OF THE ROOT, OR DESCENDING AXIS 79

Absorption by Roots ; their Growth 80

Primary and Secondary Roots 83

Annuals, Biennials 83

Perennials ......... 84

Aerial Roots 85

Epiphytes, or Air-Plants 87

Parasites 88

CHAPTER IV. — OF THE STEM, OR ASCENDING AXIS 91

Sect. I. Its General Characteristics and Mode of

Growth 91

Nodes and Internodes 92

Buds 93

Plan of Vegetation 95

Phytons 96

Sect. II. Ramification 97

Branches 97

Adventitious and Accessory Buds 98

Excurrent and Deliquescent Stems ..... 99

Definite and Indefinite Growth . . . . . .100

Propagation from Buds 100

Sect. III. The Kinds of Stem and Branches . .101

Herbs, Shrubs, Trees, &c 101

Stolons, Suckers, Runners 102

Offsets, Tendrils . . 103

Spines or Thorns 104

Subterranean Modifications 105

V1U CONTENTS.

Rhizoma or Rootstoek 106

Tuber 107

Corm 108

Bulbs and Bulblets 109

Consolidated Forms of Vegetation 110

Sect. IV. Tiik Internal Structure of thk Stem . Ill

Skct. V. Thk Endogenous or Monocotyledonous Stem 114

Sect. VI. The Exogenous or Dicotyledonous Stem 116

The First Year's Growth 118

The Wood 119

The Bark 120

The Cambium-Layer 122

Annual Increase of the Wood 123

Sap-wood and Heart-wood 124

The Bark ; its particular Structure 1 26

The Living Parts of a Tree, &c 129

The Plant a Composite Being, Individuality . . .131

Comparison of Endogenous with Exogenous Structure . 132

CHAPTER V. — OF THE LEAVES 133

Sect. I. Their Arrangement 133

Phyllotaxis 133

Vernation or Prajfoliation 143

Sect. II. Their Structure and Conformation . .145

Anatomy of the Leaf • 145

Stomata 150

Development of Leaves • 153

The Venation and Forms of Leaves 154

Compound Leaves 163

Leaves of Peculiar Conformation or Transformation . . 165

The Petiole or Leafstalk, Phyllodia, Stipules . . . 170

Sect. III. The Duration of Leaves; their Action, etc. 172

Fall of the Leaf 173

Death of the Leaf 1 74

Exhalation from the Leaves, Rise of the Sap . . . 175

CONTENTS. IX

CHAPTER VI. — OF THE FOOD AND NUTRITION OF

FLANTS 177

Sect. I. The General Physiology of Vegetation . 177

Sect. II. The Food and the Elementary Composition

of Plants 179

The Organic Constituents . . . . . . 180

The Inorganic or Earthy Constituents . . . .186

Sect. III. Assimilation, or Vegetable Digestion, and

its Results 190

Process and Results of Assimilation . . . . .191

Effect on the Atmosphere 199

Relations of the Vegetable to the Animal and Mineral King-
doms 201

CHAPTER VII. — OF FLOWERING 204

Flowering an Exhaustive Process 204

Evolution of Heat 206

Plants need a Season of Rest 207

CHAPTER VHL— OF THE INFLORESCENCE . . 209

Indefinite or Indeterminate Inflorescence . . . .210
Definite or Determinate Inflorescence . . . . 217

CHAPTER IX.— OF THE FLOWER 221

Sect. I. Its Organs, or Component Parts . . . 221

Sect. II. Its Theoretical Structure or Morphology 224

Sect. III. Its Symmetry 232

Alternation of the Floral Organs 235

Position as Respects the Axis and Bract . . . . 237

Sect. IV. The Various Modifications of the Flower 238

Augmentation of the Floral Circles 242

Chorisis or Deduplication 243

X CONTENTS.

Anteposition or Superposition 248

Coalescence of Parts . 249

Adnation or Consolidation 250

Irregularity 253

Suppression or Abortion ...... 255

Unusual States of the Receptacle 2CC

The Disk 2G7

Skct. V. The Floral Envelopes in Particular . . 2C8

Their Development or Organogeny .... 2G8

Their ^Estivation or Praefloration. 209

The Calyx 274

The Corolla 275

Sect. VI. The Stamens 279

The Filament and Anther . . . . . . .281

The Pollen 285

Sect. VII. The Pistils 287

The Simple Pistil 288

The Placenta 289

The Compound Pistil 290

Modes of Plaeentation 292

Gynaecium of Gymnospermous Plants .... 296

Skct. VIII. The Ovule 297

Sect. IX. Fertilization and Formation of the Embryo 300

Parthenogenesis 300

Access of the Pollen ........ 301

Action of the Pollen on the Stigma ..... 302

Origin of the Embryo . 304

CHAPTER X. — OF THE FRUIT 308

Sect. I. Its Structure, Transformations, &c. . . 308

The Pericarp or Seed-vessel 308

Obliteration or Alteration 309

Ripening, Dehiscence . . . . . . • 310

Skct. II. Irs Kinds 311

CONTENTS. XI

CHAPTER XL — OF THE SEED 320

Sect. I. Its Structure and Parts 320

The Nucleus and Albumen 322

The Embryo . . . . . . . . .323

Sect. II. Germination 328

CHAPTER XII. — OF REPRODUCTION IN CRYPTO-

GAMOUS OR FLOWERLESS. PLANTS . . 330

CHAPTER XIII. — OF THE SPONTANEOUS MOVEMENTS

AND VITALITY OF PLANTS .... 340

Special Directions 341

Sensible Movements from Irritation .... 345

Spontaneous or Automatic Movements . . . .34 7
Free Movements of the Spores of Algae .... 348
Locomotion of Adult Microscopic Plants .... 349

PART II.

SYSTEMATIC BOTANY.

CHAPTER I. — OF THE PRINCIPLES OF CLASSIFICA-
TION 352

Individuals 352

Species 354

Varieties, Races, Hybrids or Cross-breeds .... 355

Genera 358

Orders or Families, Classes, &c 359

Characters 362

Binomial Nomenclature 363

Natural and Artificial Systems 365

CHAPTER II. — OF THE NATURAL SYSTEM OF BOT-
ANY 386

Sketch of the Classes, &c 369

Nomenclature of Orders, Tribes, &c. . . . . 373

Xii CONTENTS.

CHAPTER III. — ILLUSTRATIONS OF THE NATURAL

ORDERS OR FAMILIES 373

CHAPTER IV. — OF THE ARTIFICIAL SYSTEM OF

LINN^US 511

APPENDIX.

Signs and Abbreviations 517

Directions for Collecting and Preserving Plants, &c. 518

GLOSSARY OF BOTANICAL TERIV^ JB INDEX . 521

THE

BOTANICAL TEXT-BOOK

INTRODUCTION.

GENERAL VIEW OP THE SCIENCE.

1. Botany is the Natural History of the Vegetable Kingdom.
The vegetable kingdom consists of those beings (called Plants)
which derive their sustenance from the mineral kingdom, that is,
from the earth and air, and create the food upon which animals
live. The proof of this proposition will be hereafter afforded, in
the chapter upon the Food and Nutrition of Plants. The vegetable
kingdom, therefore, occupies a position between the mineral and
the animal kingdoms. Comprehensively considered, Botany accord-
ingly embraces every scientific inquiry that can be made respect-
ing plants, — their nature, their kinds, the laws which govern
them, and the part they play in the general economy of the world,
— their relations both to the lifeless mineral kingdom below them,
from which they draw their sustenance, and to the animal kingdom
above them, endowed with higher vitality, to which in turn they
render what they have thus derived.

2. There are three aspects under which the vegetable world may
be contemplated, and from which the various departments of the
science naturally arise. Plants may be considered either as indi-
vidual beings ; or in their relations to each other, as collectively
constituting a systematic unity, that is, a vegetable kingdom ; or in
their relations to other parts of the creation, — to the earth, to
animals, to man.

3. ..Under the first aspect, namely, when our attention is directed
to the plant as an individual, we study its nature and structure, the

2

14 INTRODUCTION.

kind of life with which it is endowed, the organization through
which its life is manifested ; — in other words, how the plant lives
and grows, and fulfils its destined offices. This is the province of
PHYSIOLOGICAL BOTANY. This department of the science
naturally divides into two branches, namely, Structural Botany and
Vegetable Physiology, which arise from the different views we may
take of plants. The study of their organization belongs to Struc-
tural Botany, which includes every inquiry respecting their
structure and parts. And this may again be divided into two
branches, viz.: — 1st, Vegetable Anatomy, or Phytotomy, the
study of the minute structure of vegetables as revealed by the
microscope ; and 2d, Organography, the study of the organs or
conspicuous parts of plants, as to their external conformation ; in-
cluding Morphology (the study of forms), which relates to the
conformation and the symmetrical arrangement of these organs,
and the modifications they undergo, either in different species,
according to the conditions of their existence, or in the same indi-
vidual in the course of its development, — a department analogous
to what is termed Comparative Anatomy in the animal kingdom.
Thus in Structural Botany, whether we regard the external con-
formation or the m-nute internal structure, the plant is viewed as
a piece of machinery, adapted to the accomplishment of certain
ends. On the other hand, the study of this apparatus in action,
endowed with life, and fulfilling the purposes for which it was in-
tended, and also of the forces which operate in it and by it, is the
province of Vegetable Physiology.

4. The subjects which Physiological Botany embraces, namely,
Vegetable Anatomy, Organography, and Physiology, therefore,
spring naturally from the study of vegetables as individuals, —
from the contemplation of an isolated plant throughout the course
of its existence, from germination to the flowering state, and the
production of a seed like that from which the parent stock origi-
nated. These branches would equally exist, and would form a
highly interesting study (analogous to human anatomy and physi-
ology), even if the vegetable kingdom were restricted to a single
species.

5. But the science assumes an immeasurably broader interest and
more diversified attractions, when we look upon the vegetable crea-
tion as consisting, not of wearisome repetitions of one particular form,
in itself however perfect or beautiful, but as composed of thousands

INTRODUCTION. 15

of species, all constructed upon one general plan, indeed, but this
plan modified in each according to the rank it holds, and the cir-
cumstances in which it is placed. This leads to the second great
department of the science, namely, SYSTEMATIC BOTANY, or
the study of plants in their relations to one another; as forming a
vegetable kingdom, which embraces an immense number of species,
resembling each other in very various degrees, and therefore capable
of being grouped into kinds or genera, into orders, classes, &c.

6. Thus arises Classification, or the arrangement of plants in
systematic order, so as to show their relationships ; also Special
Descriptive Botany, embracing a scientific account of all known
plants, designated by proper names, and distinguished by clear and
exact descriptions. Necessarily connected with these departments
is Terminology or Glossology, which relates to the application
of distinctive names or terms to the several organs of plants, and
to their numberless modifications of form, &c. The accomplishment
of this object renders necessary a copious vocabulary of technical
terms ; for the current words of ordinary language are not suf-
ficiently numerous or precise for this purpose. New terms are
therefore introduced, for accurately expressing the great variety
of new ideas to which the exact comparison of plants gives rise ;
and thus a technical language has gradually been formed (in this
as in every other science), by which the botanist is able to describe
the objects of his study with a clearness and brevity not otherwise
attainable.

7. These several departments include the whole natural history
of the vegetable kingdom, considered independently. But, under
a third point of view, plants may be contemplated in respect to their
relations to other parts of the creation ; whence arises a series of
interesting inquiries, which variously connect the science of Botany
with Chemistry, Geology, Physical Geography, &c. Thus, the re-
lations of vegetables with the mineral kingdom, considered as to
their influence upon the soil and the air, — as to what vegetation
draws from the soil and what it imparts to it, what it takes from
and what it renders to the air we breathe ; and, again, the relations
of the vegetable to the animal kingdom, considered as furnishing
sustenance to the latter, and the mutual subservience of plants and
animals in the general economy of the world, — all these inquiries
belong partly to Chemistry and partly to Vegetable Physiology ;
while the practical deductions from them lay the foundation of

16 INTRODUCTION.

scientific Agriculture, &c. The relations of plants to the earth,
considered in reference to their natural distribution over its surface
and the laws that regulate that distribution, especially as connected
with climate, give rise to Geographical Botany, a subject which
connects Botany with Physical Geography. Under the same gen-
eral department naturally falls the consideration of the changes
which the vegetable kingdom has undergone in times anterior to
the present state of things, as studied in the fossil remains of plants,
(a contribution which Botany offers to Geology,) as well as of those
changes which man has effected in the natural distribution of
plants, and the alterations in their properties or products which
have been developed by culture.

8. Of these three great departments of the science, that of
Physiological Botany, forming as it does the basis of all the rest,
first demands the student's attention.

PART I.

STRUCTURAL AND PHYSIOLOGICAL BOTANY.

9. The principal subjects which belong to this department of
Botany may be considered in the most simple and natural order
by tracing, as it were, the biography of the vegetable through the
successive stages of its existence, — the development of its essen-
tial organs, root, stem, and foliage, the various forms they assume,
the offices they severally perform, and their combined action in
carrying on the processes of vegetable life and growth. Then the
ultimate development of the plant in flowering and fructification
may be contemplated, — the structure and office of the flower, of
the fruit, the seed, and the embryo plant it contains, which, after
remaining dormant for a time, at length in germination develops
into a plant like the parent ; thus completing the cycle of vegetable
life. A preliminary question, however, presents itself. To under-
stand how the plant grows and forms its various parts, and to get
a clear idea of what growth is, we must first ascertain what plants
are made of.

CHAPTER I .

OF THE ELEMENTARY STRUCTURE OP PLANTS.
Sect. I. Of Organization in General.
10. The Elementary Constitution of Plants. In considering the

materials of which vegetables are made, it is not necessary at the
outset to inquire particularly into their chemical or ultimate com-
position, that which they have in common with the mineral world.

2*

18 THK ELEMENTARY STRUCTURE OF PLANTS.

As they derive all the materials of their fabric from the earth and
air, plants can possess no simple element which these do not supply.
They may take in, to some extent, almost every element which is
thus supplied. Suffice it for the present to say, that, of the about
sixty simple substances now recognized by chemists, only four are
essential to vegetation and are necessary constituents of the vege-
table structure. These are Carbon, Hydrogen, Oxygen, and Nitro-
gen. Besides these, a few earthy bodies are regularly found in
plants, in small and varying proportions. The most important of
them are Sulphtir and Phosphorus, which are thought to take an
essential part in the formation of certain vegetable products, Potas-
sium and Sodium, Calcium and Magnesium, Silicon and Aluminum,
Iron and Manganese, Chlorine, Iodine, and Bromine. None of these
elements, however, are of universal occurrence, nor are they actual
components of any vegetable tissue.

11. Their Organic Constitution. Although plants and animals have
no peculiar elements, though the materials from which their bodies
spring, and to which they return, are common earth and air, yet in
them these elements are wrought into something widely different
from any form of lifeless mineral matter. Under the influence of
the principle of life, in connection with which alone such phenomena
are manifested, the three or four simple constituents effect peculiar
combinations, giving rise to a few organizable elements, as they
may be termed ; because of them the organized fabric of the vege-
table or animal is directly built up. This fabric is in a good degree
similar in all living bodies ; the solid parts, or tissues, in all assuming
the form of membranes, arranged so as to surround cavities, or form
the walls of tubes, in which the fluids are contained. It is called
organized structure, and the bodies so composed are called organized
bodies, because such fabric consists of parts co-operating with each
other as instruments or organs adapted to certain ends, and through
which alone the living principle, under whose influence the structure
itself was built up, is manifested in the operations which the plant
and animal carry on. There is in every organic fabric a necessary
connection between its conformation and the actions it is destined to
perform. This is equally true of the minute structure, or tissues, as
revealed by the microscope, and of the larger organs which the tissues
form in all plants and animals of the higher grades, such as a leaf,
a petal, or a tendril, a hand, an eye, or a muscle. The term organ-
ization formerly referred to the possession of organs in this larger

ORGANIZATION. 19

sense, that is, of conspicuous parts, or members. It is now applied
as well to the intimate structure of these parts, themselves made up
of smaller organs through which the vital forces directly act.

12. Distinctions between Minerals and Organized Beings. In no

sense can mineral bodies be said to have organs, or parts subor-
dinate to a whole, and together making up an individual, or an
organized structure in any respect like that which has just been
spoken of, and is soon (as regards plants) to be particularly de-
scribed. Without attempting to contrast mineral or unorganized
with organized bodies in all respects, we may briefly state that the
latter are distinguished from the former, — 1. By parentage: plants
and animals are always produced under the influence of a living
body similar to themselves, or to Avhat they will become, in whose,
life the offspring for a time participates ; while in minerals there is'
no relation like that of parent and offspring, but they are formed
directly, either by the aggregation of similar particles, or by the
union of unlike elements combined by chemical affinity, independent
of the influence, and utterly irrespective of the previous existence,
of a similar thing. 2. By their development: plants and animals
develop from a germ or rudiment, and run through a course of
changes to a state of maturity ; the mineral exhibits no phases in
its existence answering to the states of germ, adolescence, and
maturity, — has no course to run. 3. By their mode of growth:
the former increasing by processes through which foreign materials
are taken in, made to permeate their interior, and deposited inter-
stitially among the particles of the previously existing substance ;
that is, they are nourished by food ; — Avhile the latter are not
nourished, nor can they properly be said to grow at all ; if they
increase in any way, it is merely by juxtaposition, and because
fresh matter happens to be deposited on their external surface.
4. By the power of assimilation, or the faculty that plants and
animals alone possess of converting the proper foreign materials
they receive into their own peculiar substance. 5. Connected
with assimilation, as a part of the function of nutrition, which can
in no sense be predicated of minerals, is the state of internal ac-
tivity and unceasing change in living bodies ; these constantly under-
going decomposition and recomposition, particles which have served
their turn being continually thrown out of the system as new ones
are brought in. This is true both of plants and animals, but more
fully of the latter. The mineral, on the contrary, is in a state of

20 THE ELEMENTARY STRUCTURE OF PLANTS.

permanent internal repose : whatever changes it undergoes are
owing to the action of some extraneous force, not to any inherent
power. This holds true even in respect to the chemical combina-
tions which occur in the mineral and in the organic kingdoms. In
the former they are stable ; in the latter they are less so in pro-
portion as they are the more under the influence of the vital prin-
ciple: as if in the state of unstable equilibrium, a comparatively
slight force induces retrograde changes, through which they tend
to reassume the permanent mineral state. 6. Consequently the
duration of living beings is limited. They are developed, they
reach maturity, they support themselves for a time, and then perish
by death, sooner or later. Mineral bodies have no life to lose, and
contain no internal principle of destruction. Once formed, they
exist until destroyed by some external power ; they lie passive
under the control of physical forces. As they were formed irrespec-
tive of the pre-existence of a similar body, and have no self-deter-
mining power while they exist, so they have no power to determine
the production of like bodies in turn. The organized being may
perish, indeed, from inherent causes ; but not until it has given rise
to new individuals like itself, to take its place. The faculty of re-
production is, therefore, an essential characteristic of organized
beings.

13. Individuals. The mass of a mineral body has no necessary
limits ; a piece of marble, or even a crystal of calcareous spar,
may be mechanically divided into an indefinite number of parts,
each one of which exhibits all the properties of the mass. But
plants and animals exist as individuals; that is, as beings, com-
posed of parts which together constitute an independent whole, that
can be divided only by mutilation. Each owes its existence to a
parent, and produces similar individuals in its turn. So each in-
dividual is a link of a chain ; and to this chain the natural-historian
applies the name of

14. Species. The idea of species is therefore based upon this suc-
cession of individuals, each deriving its existence, with all its peculi-
arities, from a similar antecedent one, and transmitting its form
and other peculiarities essentially unchanged from generation to
generation. By species we mean abstractly the type or original
of each sort of plant, or animal, thus represented by a perennial
succession of like individuals : or, concretely, the species is the sum
of such individuals.

ORGANIZATION. 21

15. Life. All these peculiarities of organized, a* contrasted with
inorganic bodies, will be seen to depend upon this : that the former
are living beings, or their products. The great characteristic of
plants and animals is life, which these beings enjoy, but minerals
do not. Of the essential nature of the vitality which so controls
the matter it becomes connected with, and of the nature of the
connection between the living principle and the organized structure,
we are wholly ignorant. We know nothing of life except by the
phenomena it manifests in organized structures. We have adverted
only to some of the most universal of these phenomena, those which
are common to every kind of organized being. But these are so
essentially different from the manifestations of any known physical
force, that we are compelled to attribute them to a special principle.
We may safely infer, however, that life is not a product, or result,
of the organization ; but is a force manifested in matter, which it
controls and shapes into peculiar forms, — into an apparatus, in
which means are manifestly adapted to ends, and by which results
are attained that are in no other way attainable. As we rise in the
scale of organized structure from plants through the various grades
of the animal creation, the superadded vital manifestations become
more and more striking and peculiar. But the fundamental char-
acteristics of living beings, — those which all enjoy in common, and
which necessarily give rise to all the peculiarities above enumer-
ated (12), — are reducible to two, viz.: — 1. the power of self-
support, or assimilation, that of nourishing themselves by taking
in surrounding mineral matter and converting it into their own
proper substance ; by which individuals increase in bulk, or grow,
and maintain their life : 2. the power of self-division or reproduc-
tion, by which they increase in numbers and perpetuate the species.*

16. Difference between Vegetables and Animals. The distinction be-
tween vegetables and minerals is therefore well defined. But the
line of demarcation between plants and animals is by no means
so readily drawn. Ordinarily, there can be no difficulty in dis-
tinguishing a vegetable from an animal. All the questionable

* A single striking illustration may set both points in a strong light. The
larva of the flesh-fly possesses such power of assimilation, that it will increase
its own weight two hundred times in twenty-four hours ; and such consequent
power of reproduction, that LinnaMis perhaps did not exaggerate, when ho
affirmed that " three flesh-flies would devour the carcass of a horse as quickly
as would a lion."

22 TIIE ELEMENTARY STRUCTURE OF PLANTS.

cases occur on the lower confines of the two kingdoms, which
exhibit forms of the greatest possible simplicity of structure, and
of a minuteness of size that baffles observation. Even here the
uncertainty may be attributable rather to the imperfection of
our knowledge, than to any confusion of the essential character-
istics of the two kinds of beings. If we cannot absolutely define
them, or, at least, cannot always apply the definition to the actual
and certain discrimination of the lowest plants from the lowest
animals, we may indicate the special functions and characters of
each. The essential characteristics of vegetables doubtless depend
upon the position which the vegetable kingdom occupies between
the mineral and the animal, and upon the general office it fulfils.
Plants, as stated at the outset (1), are those organized beings that
live directly upon the mineral kingdom, — upon the surrounding
earth and air. They alone convert inorganic, or mineral, into
organic matter ; while animals originate none, but draw their whole
sustenance from the organized matter which plants have thus elab-
orated. Plants, having thus the most intimate relations with the
mineral world, are generally fixed to the earth, or other substance
upon which they grow, and the mineral matter on which they feed
is taken directly into their system by absorption from without, and
is assimilated under the influence of light in organs exposed to the
air; while animals, endowed with volition and capable of respond-
ing promptly to external impressions, have the power of selecting
the food ready prepared for their nourishment, which is received
into an internal reservoir or stomach. The permanent fabric of
plants is composed of only three elements, Carbon, Hydrogen, and
Oxygen. The tissue of animals contains an additional element,
viz. Nitrogen. Plants, as a necessary result of assimilating their
inorganic food, decompose carbonic acid and restore its oxygen to
the atmosphere. Animals in respiration continually recompose car-
bonic acid, at the expense of the oxygen of the atmosphere and the
carbon of plants. These peculiarities will be explained and illus-
trated in the progress of this work.

Sect. II. Of the Cells and Cellular Tissue of Plants.

17. The question recurs, What is the organized fabric or tissue
of plants, and how is vegetable growth effected ? The stem, leaves,

CELLULAR TISSUE,

23

and fruit appear to ordinary inspection to be formed of smaller parts,
which are themselves capable of division into still smaller portions.
Of what are these composed ?

18. Cellular Structure. To obtain an answer to this question, we
examine, by the aid of a microscope, thin slices or sections of any
of these parts, such, for example, as the young rootlet of a seed-
ling plant. A magnified view of such a rootlet, as in Fig. 1, pre-
sents on the cross-section the appearance of a network, the meshes
of which divide the whole space into more or less regular cavi-
ties. A part of the transverse slice more highly magnified (Fig. 2)
shows the structure with greater distinctness. A perpendicular
slice (Fig. 3) exhibits somewhat similar meshes, showing that the
cavities do not run lengthwise through the whole root without in-
terruption. In whatever direction the sections are made, the cav-
ities are seen to be equally circumscribed, although the outlines
may vary in shape. Hence, we arrive at the conclusion, that the
fabric, or tissue, consists of a multitude of separate cavities, with

closed partitions ; forming a structure not unlike a honeycomb.
This is also shown by the fact, that the liquid contained in a juicy
fruit, such as a grape or currant, does not escape when it is cut in
two. The cavities being called Cells, the tissue thus constructed
is termed Cellular Tissue. When the body is sufficiently trans-
lucent to be examined under the microscope by transmitted light,
this structure may usually be discerned without making a section.

FIG. 1. Portion of a young root, magnified. 2 A transverse slice of the same, more mag-
nified 3 A smaller vertical slice, magnified.

FIG. i Cellular tissue from the apple, as seen in a section. 5. Some of the detached cells
from the ripe fruit, magnified.

FIG 6 Portion of a hair from the filament of the Spider Lily (Tradescantia), magnified:
o, vestige of the nucleus.

24

THE ELEMENTARY STRUCTURE OF PLANTS.

ODQCGDQC:

We may often look directly upon a delicate rootlet (as in Fig. 1),
or the petal of a flower, or a piece of thin and transparent sea-weed,
and observe the closed cavities, entirely circumscribed by nearly
transparent membranous walls.

19. Does this cellular tissue consist of an originally homogeneous
mass, filled in some way with innumerable cavities ? Or is it com-
posed of an aggregation of little blad-
ders, or sacs, which by their accumu-
lation and mutual cohesion make up
the root or other organ? Several cir-
cumstances prove that the latter is the
correct view. 1. The partition between
two adjacent cells is often seen to be
double ; showing that each cavity is
bounded by its own special walls.
2. There are vacant spaces often to
be seen between contiguous cells, where the walls do not entirely
fit together. These intercellular spaces are sometimes so large
and numerous, that many of the cells touch each other at a few
points only; as in the green pulp of leaves (Fig. 7). 3. When
a portion of any young and tender vegetable tissue, such as an
Asparagus shoot, is boiled, the elementary cells separate, or may
readily be separated by the aid of fine needles, and examined by
the microscope. 4. In pulpy fruits, as in the apple, the walls of
the cells, which at first cohere together, spontaneously separate as
the fruit ripens (Fig. 4, 5).

20. The vegetable, then, is constructed of these cells or vesicles,
much as a wall is built up of bricks. When the cells are separate,
or do not impress each other, they are generally
rounded or spherical. By mutual pressure they be-
come many-sided. In a mass of spheres each one is
touched by twelve others ; so, if equally impressed in
every direction, the yielding cells, flattening each
other at the points of contact, become twelve-sided ; and in a
section, whether transverse (as in Fig. 2) or longitudinal (as in

FIG 7 A magnified section through the thickness of a leaf of Illicium Floridanum, show-
ing the irregular spaces or passages between the cells, which are small in the upper layer of
the green pulp, the cells of which (placed vertically) are well compacted, so as to leave only
minute vacuities at their rounded ends ; hut the spaces are large and copious in the rest of
the leaf, where the cells are very loosely arranged, a, The epidermis or skin of the upper,
b, of the lower surface of the leaf, composed of perfectly combined and thick-walled cells

FIG. 8 View of a twelve-sided cell, detached entire, from tissue like that of Fig S.

CELLULAR TISSUE

25

Fig. 3), (he meshes consequently appear six-sided. If the organ
is growing in one direction more than another, the cells commonly
lengthen more or less in that
direction. It is not necessary to
detach a cell in order to ascertain
its shape ; that may usually be
inferred from the outlines of the
section in two or three directions.

21. The shape of cells, there-
fore, when they compose a tissue,
depends very much upon the way
in which they are arranged and
press upon each other. When
separate, as they are in the sim-
plest vegetables, or when nearly
free from each other, like the hairs on the surface of many plants,
they determine their own form by their mode of growth, and assume
a great variety of shapes, some of Avhich are shown in the follow-
ing illustrations. The natural and primitive form may be said to
be roundish or spherical. By increased growth in one direction
they become ohlong or cylindrical, or, when still more extended,
they become tubes. Of this kind are the hair-like prolongations
on the surface of young rootlets (shown just beginning in Fig. 1,
and more elongated in Fig. 135-137); and the fibres of cotton
are slender hairs-, consisting of single, very long cells, growing on
the surface of the seed.

22. The walls of young cells are transparent and colorless. The
various colors Avhich the parts of the plant present, the green of
the foliage, and the vivid hues of the corolla, do not belong to the
tissues themselves, but to the matters of different colors which the
cells contain (92). As they become older, the walls often lose most
of their transparency, and even acquire peculiar colors, as in the
heart-wood of various trees.

23. The cells vary greatly in size, not only in different plants,
but in different parts of the same plant. The largest are found in
aquatics, and in such plants as the Gourd, where some of them are
as much as one thirtieth of an inch in diameter. Their ordinary
diameter in vegetable tissue is between 2|lT and y^g- of an inch.

FIG. 9 A small portion of the tissue of pith, seen both in transverse and longitudinal
section, much magnified.

3

26 THE KLKMKNTA11Y STRUCTURE OE PLANTS.

The smaller of these sizes would allow of as many as 1728 millions
of cells in the compass of a cubic inch !

24. Some idea may be formed respecting the rate of their pro-
duction, by comparing their average size in a given case with the
known amount of growth. Upon a fine day in the spring, many
stems shoot up at the rate of three or four inches in twenty-four
hours. When the Agave or Century-plant blooms in our conser-
vatories, its flower-stalk often grows at the rate of a foot a day ; it
is even said to grow with twice that rapidity in the sultry climate to
which it is indigenous. In such cases, new cells must be formed at
the rate of several millions a day. The rapid growth of Mushrooms
has become proverbial. A gigantic species of Puff-ball has been
known to attain the size of a large gourd during a single night:
in this case the cells of which it is composed are computed to have
been developed at the rate of three or four hundred millions per
hour. But this rapid increase in size is owing, in great part, to the
expansion of cells already formed.

25. The Cell as a living Organism. Thus far we have considered
only the membrane or permanent Avail of the cell, — that which
makes up the tissue or fabric of plants, and which remains un-
altered, and performs some of its offices even long after life has
departed. But Ave should now regard the cell as a living thing,
and consider what the wall encloses, and what operations are
effected in it. For the whole life of the plant is that of the cells
which compose it ; in them and by them its products are elaborated,
and all its vital processes carried on.

.26. A young, living, vitally active cell consists, — 1st, of the
membrane or permanent Avail, already described ; 2d, of a delicate
mucilaginous film, lining the wall, called by Mohl the primordial
utricle ; 3d, most commonly the centre of the cell, and sometimes
the greater part of the cavity, is occupied by the nucleus, a soft
solid or gelatinous body; and 4th, the space between the nucleus
and the lining membrane is filled at first by a viscid liquid, called
protoplasm, having an abundance of small granules floating in it.
As the cell enlarges by the groAvth and expansion of its Avails, the
space betAveen the latter and the nucleus becomes filled Avith watery
sap, leaving the protoplasm merely as a viscid coating of the inside
of the primordial utricle, and of the nucleus, if this remains.

27. The cell-membrane, or proper Avail of the cell, is chemically
composed of the three elements, carbon, hydrogen, and oxygen,

FORMATION AND GROWTH OF CELLS. 27

and has the same composition (when pure) in all plants. This sub-
stance — the general material of vegetable fabric — is called Cellu-
lose. Its chemical composition is Carbon 12, Hydrogen 10, and
Oxygen 10. It is insoluble in water, alcohol, ether, and dilute acids,
and, like starch, it turns blue when acted upon by iodine, aided by
sulphuric acid. The primordial utricle, or delicate lining of the
cell, appears to have the same composition as protoplasm. It may
be regarded as an exterior portion of the mucilaginous protoplasm,
which has acquired the consistence of a very soft membrane. In
addition to the three elements, carbon, hydrogen, and oxygen, pro-
toplasm contains nitrogen, in considerable quantity. It is colored
yellow by iodine, and is coagulated by alcohol* and acid*. The
substance of which it principally consists is named by chemists
Proteine, and is known among vegetable products under various
forms, viz. as diastase, gluten, fibrine, vegetable albumen, and the
like. Such being the nature and the parts of the cell, we may now
consider

28. Its Formation and Growth. Under this head we may briefly
explain, as far as we are able, — 1st, how cells are originated; and
2d, how they are multiplied.

29. Original Cell-Formation. Cells are originated only within other
cells, or at least in matter which has been contained in and elab-
orated by them. They appear to be formed in the following man-
ner. A portion of the elaborated or organizable matter, which
abounds in the fluid contents of living cells, condenses into a soft
solid, or half-solid and more or less transparent mass, usually of a
globular or oval shape, the nucleus : around this nucleus a portion of
protoplasm accumulates ; a denser film of the same substance forms
on the surface of the protoplasm, giving the mass a definite outline ;
this is the primordial utricle : upon this a layer of cellulose is soon
deposited, making the cell-membrane. The nuclei in such cases are
very minute, and either few or many of them may be formed in
one parent cell, and be developed in this way into new cells, which
are, at least at first, of small size as compared with the parent cell
(Fig. 88). A variation of this mode occurs in many of the lower
Algae, where a considerable portion of the contents of a cell con-
denses into a rounded mass, the surface becomes coated with a
layer of protoplasm or primordial utricle, and this with a membrane
of cellulo e, completing the cell. Thus, in Vaucheria the whole
green contents at the end of certain branches condense into a

28 THE ELEMENTARY STRUCTURE OF PLANTS.

globular mass (Fig. 89), which at length is coated with cell-mem-
brane, and so becomes a cell of considerable size. In Zygnema
(Fig. 635) the whole contents of two cells are united, and give
rise in a similar way to one new cell.

30. In the higher or flower-bearing division of plants, this process
of original or free cell-formation occurs only in the sac in which the
embryo is formed. The first cell of the embryo originates in this
way ; but all the subsequent growth is effected by a different pro-
cess. In the simplest grade of plants it occurs more frequently,
but only in the formation of those bodies which in them take the
place and fulfil the office of seeds ; that is, which serve for repro-
duction.

31. It appears, therefore, that the azotized or nitrogenous mate-
rial, the proteine, plays the most important part in the formation
of cells. The layer of protoplasm, with its delicate coating, the
primordial utricle, precedes the proper cell-membrane, and in
some unexplained way causes the latter to be deposited on its sur-
face. And these soft nitrogenous parts are the seat of the whole
vital activity of the cell. The wall of cellulose may be regarded
as a kind of protecting coat or shell, which constitutes the per-
manent fabric of the plant, but is alive only so long as the living
protoplasmic lining remains.

32. In a growing young cell, the walls enlarge much faster than
the nucleus, and the latter soon ceases to grow at all. It is there-
fore left in the centre, or else remains adherent to the wall on one
side, where traces of it may often for a long time be detected ; or
more commonly it dissolves and disappears altogether. At length,
in older cells, the liquid contents and the protoplasmic lining also
disappear, and only the walls of cellulose remain as the permanent
vegetable fabric. The fabric of plants, however, as has already
been stated, is not built up by original cell-formation, but by

33. Cell-Multiplication. A living cell, formed in Avhatever manner,
has the power of multiplying itself by dividing into two, these again
into two more, and so on. By this process the single cell, which
each vegetable begins Avith, gives rise to the embryo or rudimen-
tary plantlet contained in a seed ; and by it the embryo in germina-
tion develops into a seedling, and the seedling into the herb, shrub,
or tree. Vegetable growth accordingly consists, — 1st, of the growth
or expansion of each cell up to its full size, which ordinarily is very
soon attained ; and 2d, of what is called their merismatic multiplied-

FORMATION AND GROWTH OV CKLLS.

29

©

tion, namely, the successive division of cells into two. This takes

place only when they are young and active, and mostly before they
are full-grown. It is effected by the formation of a

partition across the cavity of the cell, dividing it into ( &J

two (Fig. 10-14). In this way, a single cell gives J0
rise to a row of connected cells, when the division

takes place in one direction only ; or to a plane or | <&)

solid mass of such cells, when it takes place in two K®J

or more directions, thus producing a tissue. "

34. In this multiplication of cells by division, as in f^%
the original formation of a cell, the contents and the f $p%
■protoplasmic lining play the most im- i2
portant part. The nucleus, when pres-
ent, as it commonly is, first divides /^z\

into two (Fig. 11) ; then the lining mem- r '" \

. . . . fevSJa

brane, or primordial utricle, is gradu- f ^1

ally constricted or infolded at the line 13

of division, which, soon meeting in the
centre, separates the whole contents ( j

into two parts by a delicate partition ; (jljk

upon this a layer of cellulose is de- LJ^\
posited as a permanent wall, which /-/H"]
QO O© completes the transformation of one '{{"

€$© g©@ cell into two (Fig. 21, 22).

3.5. Cells multiplying in this way, and remaining
united, build up a row or a surface of cells, or a solid tissue, ac-
cording to the mode of division. But in many of the simplest
plants, growing in water, the cells separate as they form, and be-
come independent. A microscopic plant very common in shallow
pools in early spring, forming slimy green masses, well illustrates
this, as shown in Figures 15-19. At each step of this multipli-
cation new cell-membranes are formed, and the old one, for instance,
the wall of Fig. 15 and the common envelope of the two in, Fig. 17,

O

US?

mm

18
QOOO

OQO©

FIG. 10 A young cell, — the first cell of an embryo, — with its nucleus in the centre.
II The same, with its nucleus divided into two, and a cross-partition beginning to form.
12. The partition completed, so converting the first cell into two 13 The lower one again
divided into two, making three cells in a row. 14 The fourth cell converted into four by a
division in two directions, forming seven cells in all.

FIG. 15. A single <ell, or plant of a kind of Palmella, magnified 1G. The same dividing,
and, 17, completely separated into two. 18. Each of these dividing in the opposite direc-
tion, four cells are produced 19. Each of these again dividing into four, they produce a
cluster of sixteen cells.

3*

THE ELEMENTARY STRUCTURE OF PLANTS.

and of the four in Fig. 18, forms a part of the thickness of the
coat of each, or is destroyed by the distention, or else (as in the
present instance) is dissolved into a jelly A slight modification of
this process occurs in .„„ O2lo «

36. Free Cell-Multiplication within

a Mother-Cell, which is intermediate
in character between original cell-
formation and ordinary cell-multi-
plication. Here the whole contents
of a living cell, by constriction or
infolding of the primordial utricle,
divide into two or four parts (as
in Fig. 81 — 83), and these may be
again divided ; — each portion has
a coat of cellulose deposited over
its surface, and thus so many sep-
arate cells are produced, lying loose
in the cavity of the mother-cell, whose thin and
now dead cellulose-wall, which is all that is left of
it, usually disappears sooner or later, or is broken
up by the growth of the new crop of cells within.
In this way are formed the grains of pollen in the
anther, and the spores, or bodies which answer to
seeds, in the higher grades of Flowerless Plants.

37. Cell-Growth. By appropriating assimilated
matter, the young cell increases in size until it
attains its full growth ; its walls, as they expand

and enclose a greater space, not diminishing, but rather increasing
in thickness. Therefore it not merely enlarges, but grows. If it
grows equally in all directions, and is not pressed upon on any side,
it -keeps a spherical form ; if it grows more in one direction than in
any other it becomes oblong or cylindrical. In this way a cell is
sometimes drawn out into a slender tube ; of which the fibres of
cotton, and the cells of fibrous bark (Fig. 49) are good examples.
In the simplest plants, cells sometimes continue to elongate almost

FIG 20 The branching summit of a plantlet of Conferva glomerata, magnified ; after
Mohl The plant consists of a row of cells, filled with green grains floating in liquid : the
long cell at the upper end is seen in the process of dividing into two, at a, by constriction of
the primordial utricle.

FIG 21. A portion of the same at a, more magnified, showing the formation of the par-
tition. 22. Same, with the partition completed.

CIRCULATION IN CKLLS. 31

indefinitely from one end, by a sort of gemmation or budding growth,
•while all the rest remains stationary, or while the opposite extremity
is dead or decaying. Fig. 20 would represent a case of the kind,
except that partitions form, as the upper end grows on, dividing the
tube into a toav of cylindrical cells. Sometimes a new point of
growth commences on the side of a cell, so giving rise to

38. Branching Cells. The hair-
like bodies that copiously appear
on the surface of young rootlets
furnish examples of the kind, as
is shown in Fig. 1, 23, 24. More
conspicuous examples are furnish-
ed by certain Algae of the simplest
structure, where the cell branches
profusely as it elongates, but the
tubes are all perfectly continu-
ous throughout ; as in Botrydium
(Fig. 88), where an originally
spherical cell is extended and
ramified below in the fashion of
a root; in Vaucheria (Fig. 89),

where a slender tube forks or branches sparingly ; and in Bryopsis
(Fig. 91), where numerous branches are symmetrically arranged in
two opposite rows, like the plume of a feather. In these cases, the
fully developed plant, with all its
branches, is only one proliferous
cell, extended from various points
by this faculty of continuous bud-
ding growth. The mycelium or
spawn of Mushrooms, and the in-
tricate threads of Moulds (Fig.
92-94) are formed of very attenuated branching cells. And in
Lichens and many Fungi, cells of this kind are densely interwoven
into a filamentous tissue (Fig. 25).

39. Cyclosis or Circulation in Cells. In all young cells, probably,

at least at some period, the fluid protoplasm interposed between the
cell-walls and the watery sap is in a state of movement. Under

FIG 23 Magnified cellular tissue from the rootlet of a seedling Maple ; some of the ex-
ternal cells growing out into root-hairs 24 A few of fie cells more highly magnified

FIG 25 Entangled, filamentous, branching cells from the fibrous tissue of the Reindeer
Lichen (Cladonia rangiferina), magnified.

32

THE ELEMENTARY STRUCTURE OF PLANTS.

the microscope, currents, rendered more visible by the contained
granules or solid atoms, are seen flowing around the cell, vr around
some portion of its periphery, in a circuit which returns upon itself!
The cause of this curious phenomenon and the object it subserres
are unknown; but it is doubtless a vital circulation, and not a
mechanical movement. In most plants it is not to be seen in
mature cells. But it may be observed in many
water-plants when full-grown, and in the hairs on
the sui-face of a great variety of land-plants. The
string of bead-like cells which compose the jointed
hairs of the common Spider Lily (Tradescantia,
Fig. 6) show this circulation Avell, under a magni-
fying power of about four hundred diameters.
With this power, a set of thread-like currents
may be seen to move between the cell-wall and
the enclosed colored contents, traversing the cell
in various directions, without much regularity, ex-
cept that the streamlets appear to radiate from,
and return to, the nucleus. The large stinging
hairs of Nettles, and the bristles on the ovary of
Cimea, show this circulation very well. In the
latter, instead of the separate and slender stream-
lets of Tradescantia, we perceive a broad and con-
tinuous stream flowing up on one side of the long
cell, around the summit, and down the opposite
side. This circulation may be more readily ob-
served in the cells of many aquatic plants. In
26 Chara and Nitella, — plants composed of large

cells lined with green granules, — a magnifying power of fifty or
one hundred diameters shows the circulation very well. And the
leaves of Vallisneria spiralis (the Tape-grass or Eel-grass of fresh
water) are still more beautiful objects, when magnified from two to
four hundred diameters. Through their nearly transparent walls, a
current of protoplasm, usually carrying with it some globular loose
grains of chlorophyll, may be seen coursing up the entire breadth
of the wall of each cell, across its summit, down the opposite side,
and across the other end to complete the circuit ; and often the
current is strong enough to set the large nucleus, or a central mass

FIG. 26 A few cells of the leaf of Naias Texilis, highly magnified, showing the circulation ;
the direction of the currents indicated by arrow-heads. (Drawn by II. J Clark )

CIRCULATION IN CELLS ! ENDOSMOSE. 33

of green grains, into revolution. The circulation is more active in
the subjacent than in the superficial layer of cells, although occasion-
ally conspicuous in the latter : it is stopped or retarded by lower-
ing, and accelerated by raising the temperature. The motion often
appears to be quite rapid ; but it should be remembered that this is
magnified as well as the object. Mohl states it to be very slow, not
more than the -5^ of a lire per second in the hairs of Tradescan-
tia. But in Yallisneria the green grains sometimes complete the
circuit of a cell of the ordinary size in less than twenty seconds ;
and in the bristles on the fruit of Circaea, which are half a line
long, Mr. H. J. Clark has seen the revolution completed in about a
minute. The circulation in one cell is totally independent of that
in the adjacent ones. The current is commonly seen to flow in
opposite directions on the two sides of a partition, or to move on
one side when quiescent on the other. Cyclosis, whatever its
nature may be, evidently has nothing to do with the

40. Transference of Fluid from Cell to Cell, All cells, at least when

young and living, have perfectly closed walls. There is no passage
from one to another through visible openings or pores, although
such openings may be formed in older parts. Nevertheless fluids
do permeate cell-walls, as they do all organic membranes. And in
this way water, along with other matters which the roots absorb, is
carried up into the leaves even of the topmost bough of a tree,
passing in its course through many millions of apparently water-
tight partitions. However governed by forces inherent in the plant,
the actual transference of fluids from one cell to another takes place
in obedience to a physical law, i. e. by the process which has been
named Endosmose or Endosrnosis,* and which operates in dead parts

* Endosmose and erosmose are names given by Dntrochct (a French physi-
ologist) to a physical process of permeation and interchange which takes
place in fluids, according to the following law, briefly stated. When two
liquids of unequal density are separated by a permeable membrane, the
lighter liquid or the weaker solution will flow into the denser or stronger,
with a force proportioned to the difference in density {endosmosis) ; but at the
same time, a smaller portion of the denser liquid will flow out into the weaker
(exosmosis). Thus, if the lower end of an open tube, closed with a thin men
brane, such as a piece of moistened bladder, be introduced into a vessel of pure
water, and a solution of sugar in water be poured into the tube, the water from
the vessel will shortly be found to pass into the tube, so that the column of
liquid it contains will increase in height to an extent proportionate to the
strength of the solution. At the same time, the water in the vessel will become

34 THK ELEMENTARY STRUCTURE OF PLANTS.

as well as in living ones. Tae law is, that when two fluids of un-
equal density are separated by an organic membrane, or by any thin
and porous partition, an interchange takes place, — more or less
rapidly according to the thinness of the intervening partition and
the difference in the density of the fluids on the two sides, — a small
quantity of the denser fluid passing into the lighter, but a much larger
portion of the lighter passing into the denser ; and this continues
until the two fluids are brought to the same density. Hence, as
the cells of a living plant always contain organizable or assimilated
matter (mucilage, protoplasm, &c), which especially abounds in
young and growing parts, the cells of the rootlets are always able
to imbibe the ordinary moisture which is presented to them in the
soil ; and by diminishing the portion of water, or in any other way
increasing the density of the liquid contents of the cells of any part
of the plant, a flow may be attracted into them.

41. Increase of Cell-walls in Thickness. Up to a certain point, the

walls of cells thicken as they grow by the incorporation of new
matter interstitially into their substance. After attaining, for the
most part rapidly, a definite size, the cell ceases to enlarge, and its
wall no longer incorporates new materials. Some cells remain with
exceedingly thin and delicate walls. But in most cells that make
part of the permanent structure of a plant, the cell-membrane con-
tinues to thicken long after it has ceased to enlarge. Then the
new matter can no longer be incorporated with the old ; but
the thickening is now effected by its deposition on the inner sur-
face of the original membrane, between it and the protoplasmic

slightly sweet ; showing that a small quantity of sirup has passed through the
pores of the membrane into the water without, while a much larger portion of
water has entered the tube. The water will continue to enter the tube, and a
small portion of sirup to leave it, until the solution is reduced to the same
strength as the liquid without. If a solution of gum, salt, or any other sub-
stance, be employed instead of sugar, the same result will take place. If the
same solution be employed both in the vessel and the tube, no transference or
change will be observed. But if either be stronger than the other, a circulation
will be established, and the stranger solution will increase in quantity until the
two attain the same density. If two different solutions be employed, as, for
instance, sugar or gum within the tube, and potash or soda without, a circula-
tion will in like manner take place, the preponderance being towards the denser
fluid, and in a degree proportionate to the difference in density. Instead of ani-
mal membrane, any vegetable matter with fine pores, such as a thin piece of wood,
or even a porous mineral substance, may be substituted, with the same result.

THICKENING OK THE WALLS OF CLLLS.

85

lining. Every degree of this secondary deposition occurs, from a
slight increase in the thickness of the memhrane to the fillin"-
up of the greater part of the cavity of the cell. Any hard wood
furnishes illustrations of this. Indeed, the difference between sap-
wood and heart-wood in trees is principally owing to the increase
of this deposit, which converts the former into the latter ; as may
be seen by comparing, under the microscope, the tissue of the older
with that of the newest rings of wood,
taken from the same tree. Figures
196-199 show this in a piece of oak
wood. Fig. 29 represents a highly
magnified cross-section of some wood-
cells from the bark of a Birch, with 2? 23
their calibre almost obliterated in this way. It is by the same
process that the stone of the peach, cherry, &c. acquires its extreme
hardness. Similar indurated cells of the same kind are met with

even in the pulp of some
g fruits, as in the gritty grains,
which every one has noticed
in the flesh of certain pears,
especially of the poorer sorts.
A section of a few cells of the
kind is represented in Fig.
27, with their cavity much
reduced and rendered very
•regular by this internal in-
crustation. Similar cells may
be found in some parts of the tissue even of such juicy fruits as the
cranberry and the blueberry (Fig. 28).

42. The thickening matter, when pure, is of the same nature as
the original membrane of the cell, that is, it consists of cellulose
(27). But with this are mingled some mineral matters, — small
quantities of which must needs be dissolved in the water which
the plant imbibes by its roots, and be deposited in the cells of the

FIG. 27 Magnified section of the gritty cells of the pear ; the cavity almost filled with an
internal deposit. 28. Similar cells found in the pulp of the blueberry (Vaccinium corym-
bosum).

FIG 29. Highly magnified cross-section of a bit of the old liber of the bark of the Birch ;
the tubes nearly filled with a deposit of solid matter in concentric layers. (From Link )

FIG 30. Highly magnified wood-cells (seen in transverse and longitudinal section), from
the root of the Date Palm ; showing the thickening deposit in layers, and some connecting
canals or pits. (From Jussieu, after Mirbel )

36 THE ELEMENTARY STRUCTURE OF PLANTS.

wood, and especially in those of the leaves, where much of the water
escapes by evaporation, — and sometimes certain coloring matters
also, such as give the different tints to heart-wood, &c. Even
when purified as much as possible from all admixture of foreign
materials, the secondary deposit is said to differ a little from cellu-
lose, or original cell-membrane, in containing a somewhat larger
proportion of carbon and hydrogen : it is therefore richer in combus-
tible matter. Forming as it does the principal part of the weight
of wood {lignum), it has received the name of Lignine (also that of
Sclerogen) ; but it is only cellulose a little modified. This differ-
ence in chemical composition, however, shows why the hard woods,
such as hickory and oak, which abound in this lignified deposit,
should be more valuable for fuel, weight for weight, than the soft
woods, which have little of it ; at least, when the latter are not
charged with resinous matter.*

* 43. The section of the Avail of a cell thickened by internal
deposit, when moderately magnified, commonly appears to be homo-
geneous and uniform. But under a high magnifying power it may
often be distinguished more or less distinctly into successive con-
centric layers (Fig. 27-31). However this may be, it rarely hap-
pens that the thickening deposit is spread evenly over the whole
inner surface of a cell. It is commonly interrupted or much thinner
at some places, so as to give the diminished cavity of the cell very
irregular outlines (as in Fig. 27, 28) ; or else it is wanting at cer-
tain small and definite spots, which, being more transparent, when
looked down upon from the outside appear like holes or pores (Fig.
32, 56, 57) or slits (Fig. 58, 59), according to their shape. In this
way are formed the various

44. Markings of the Walls of .Cells. These, whether in the form of
bands, spiral lines, dots, or apparent pores, all arise from the unequal

* From the manner in which the thickening takes place, it would appear that
the innermost layers must always be the most recent. But M. Tre'cul has con-
vinced himself that the primary cell-membrane sometimes produces a secondary
one outside of itself, as well as on the inside, so that the oiiginal cell-wall is
intermediate. And also, that, when the thickening deposit is wholly within the
primary wall, the intermediate layers are occasionally secreted 'in some way by
the outer or inner ones, and therefore more recent than the inner. Unlikely
as all this seems, M Trend's investigations are entitled to great attention.
His elaborate memoir, upon Secondary Formations in Cells, is published in the
Annates des Sciences Naturclles, 4th ser. Vol. IT. 1854.

MARKINGS OF THE WALLS OF CICLLS.

distribution of the secondary deposit. They are portions of the
Avails which are either thinner or thicker than the rest. These
markings display the greatest variety of forms, many of them of
surpassing elegance. The principal kinds occur with perfect uni-
formity in each species or family, and in definite parts of the plant ;
so that, in a multitude of cases, the sort of plant may be as certainly
identified by the minute sculpture of its cells alone, as by more con-
spicuous external characters. They are preserved even when the
tissue is fossilized, and the 33

external form, with every
outwai'd appearance of or-
ganization, is obliterated.
Through thin slices and

--sfe,.p- JO

HH

mt

^WA

other contrivances, the hid- |j
den structure is revealed
under the microscope, and
thus the true nature of the
earth's earliest vegetation
may be often satisfactorily made out.
In this way, and by taking advantage of
the fact, that the secondary deposits in
the cells contain a good deal of mineral
matter, which is left behind in the ashes,
Professor Bailey was able first to dis-
cover vegetable structure in anthracite
coal.* The simplest and commonest
markings are those which appear as
pores or holes, but are really

45. Dots or Pits, such as those on the
cells of the pith of Elder (Fig. 38), and

tSOP

* See Silliman's American Journal of Science and Arts, New Series, Vol. I.

FIG 31. Magnified cross-section of a small portion of heart-wood of the Plane-tree or
Buttonwood (Platanus occidentalis). 82. A corresponding longitudinal section, parallel with
the circumference a, The dotted woody tissue ; the lower ends of the two cells to which the
letters are appended are divided lengthwise, so as to show the irregularly thickened calibre ;
the others are mostly entire, showing the dots : in the cross-section the secondary deposit is
seen to form indistinct layers, and some of the dots to form cauals of lateral communication.
b, Dotted ducts : the middle one in the longitudinal section is obliquely joiuted c, Medullary
ray.

FIG. 33. Portion of four cells of the woody tissue, with both transverse and longitudinal
section, highly magnified, showing the canals or deep pits in the thickened walls, and their
apposition in adjoining cells : on the cross-section the layers of deposit are more plainly visible

38

THIS ELEMKNTAKV ST11UCTURK OF PLANTS.

upon what are called dotted ducts ; as in Fig. 32, b, and Fig. 56, 57.
All markings of this kind are thin spots, which, for some reason,
have not partaken in the general thickening of the wall. Although
they are not primarily pores or real perforations, yet they often be-
come so with age, by the destruction of the thin primary membrane,
after the cell has lost its vitality. Fig. 32 shows these dots on the
wood-cells and the ducts of the Plane-tree. And Fig. 33, represent-
ing some of the wood-cells more highly magnified, explains their
real nature, namely, as deep pits in the thick wall. It will be seen
that the pits of contiguous cells exactly correspond ; showing that
there is nothing accidental in the origin or the arrangement of these
markings. They are manifestly designed for maintaining communi-
cation between contiguous cells, and for the ready conveyance of the
sap from cell to cell, notwithstanding the thickening of their walls.
Of similar nature, although of greater size, are the so-called

oft

1

3

®

G

\

§

A

Q

e

0

3

0

0

0

0

9V

0

f

°l

©\

£

V

©

0

or

0

0

© C~;

4? *n

[ °J

/5=\ 1

\®<

©

P

1

'©'

%

l©l

0

V 1

1 '

I® 1

46. Discs or Circular Markings of Coniferous Wood (Fig. 34-37).

These are of universal occurence in the wood of Pines, Firs, and all
that family of Coniferous trees ; and something very like them, if
not the same, occurs in the Winter's-Bark tree (as long ago shown
by Mr. Brown), the Star- Anise, and even in the Magnolia, and other
aromatic trees. They may readily be seen in a thin Pine shaving,
taken parallel with the silver-grain : for in the Pine family they are
nearly all found on the lateral walls of the cells, few or none being
visible on the sides which look towards the bark or towards the

FIG. 34. Piece of a Pine shaving, magnified, to show the discs or thin spots which appear
on the cells of all Coniferous wood 35. A separate cell of the above, more strongly magnified.

FIG 36. A small portion of five cells of White-Pine wood magnified ; seen both in trans-
verse and longitudinal section, n, a, discs, in transverse section : 6, 6, discs as looked down
upon in longitudinal view.

FIG. 37. A highly magnified transverse section of one complete wood-cell, connected with
adjacent cells, and of a disc (a) : after Mohl.

MARKINGS OF THE "WALL'S OF CKLLS.

39

pith ; while the smaller dots, of the ordinary kind, as on the wood-
cells of the Plane-tree (Fig. 32), are most abundant on the sides that
look towards the centre and the circumference of the trunk. The
nature of these disc-like markings is plainly revealed in the accom-
panying microscopical dissections of White-Pine wood (Fig. 36, 37).
They are thin places, which have not received the thickening deposit
that has lined all the rest of the calibre, or have received it in a
lesser degree. Those of contiguous wood-cells always exactly cor-
respond, just as do the smaller dots or pits of ordinary wood; and
the two cell-membranes separate from each other, each being some-
what curved inward, thus leaving a lenticular space between them,
like that between two watch-glasses put together by their edges.

47. Bands, Rings, or Spiral Markings. These are mostly definite
portions of the wall more thickened than the rest ; as is shown by
the spiral vessel, where the secondary formation is restricted to a
delicate thread, capable of being unwound (GO), and particularly
by the remarkably thick plate which winds around in the cells of
certain Cacti, like a spiral staircase (Fig. 42, 43). The accompany-
ing figures illustrate various forms of banded, reticulated, or spiral
markings.

48. When the primitive walls of such banded cells remain very
thin and delicate, they are apt to become obliterated at maturity,
leaving the firmer fibrous markings as separate threads. This

FIG. 38. A cell of the pith of Elder, marked with oblong dots, which are thin places

FIG. 39. Cells of the leaf of Sphagnum, or Peat-Moss, marked with a spiral fibre.

FIG. 40 - 43 Spirally banded cells from species of Cactus, after Schleiden

FIG. 44. Hairs from the seed-coat of Dipteracanthus strepens ; one with a spiral band, the

other with a set of rings developed on the inner surface of the tube.
FIG. 45. Tissue from the lining of the anther of Coba;a scandens ; where, the delicate walls

of the cells being soon obliterated, nothing but the fibrous bands with which they were marked

40 THE ELEMENTARY STRUCTURE OF TLANTS.

occurs in the tissue that lines the walls of the anther ; and in this
way the spirally marked tubes (called Elaters) which occur in the
spore-cases of the Hepatic Mosses or Liverworts are converted into
elastic spiral threads. Of a similar nature are the

49. Gelatinous Coils, or soft spiral threads, such as occur in the
hairs or projecting cells which invest the coats of many seeds or
seed-like fruits, and which when moistened often uncoil and are
projected from the bursting cell in a striking manner. When water
is applied, this is absorbed by endosmosis (40), the gelatinous threads
swell, burst the cell-membrane, and gush out in the form of uncoil-
ing mucilaginous fibres or bands. Good examples of the kind are
furnished by the seeds of Collomia and Gilia, and by hairs or papilla?
on the seed-like fruits of numerous species of Senecio and the allied
genera. Those of Crocidium project a thick, mucilaginous, twisted
band, in place of a thread. They may subserve a useful purpose in
fixing light seeds to the ground where they lodge, by means of the
moisture of the first shower they receive.

Sect. III. Of the Kinds or Transformations of Cellular
Tissue ; viz. Woody Tissue, Ducts, etc.

50. The statements of the preceding section apply in general to
the cells of which all plants are composed, irrespective of the mani-
fold forms they may assume, and of some peculiar transformations
they may undergo. Some of these should now be specified ; as
they give rise to kinds of tissue so unlike the ordinary cellular, in
outward appearance at least, that they have always been distin-
guished by special names. We allude particularly to Woody Tissue
or Woody Fibre, and Vascular Tissue or Vessels, of various forms.
These, although formerly regarded as of independent origin, are
now known to be mere modifications of one common type, the cell,
and are produced in the same mode as ordinary cells. So all the
statements of the foregoing section, in respect to the formation, mul-
tiplication, and growth of cells, are equally applicable to these also.
Some kinds differ from ordinary cells in shape alone ; others result
from their combination or confluence. This is shown in two ways :
first, by noting the intermediate gradations which may be found be-
tween every particular sort; and secondly, by watching their de-
velopment and tracing them directly from their earliest condition, as

PARENCHYMA AND PROSKNCHY.MA.

■11

ordinary cells, to the peculiar forms they soon assume. In enumer-
ating the kinds of vegetable tissue, we commence with cellular tissue
strictly so called, or

51. Parenchyma. This is the distinctive name for ordinary mem-
branous cellular tissue in general, such as that which forms the pith
of stems and their outer bark. In the most restricted application, it
belongs to such tissue when composed of angular or polyhedral cells
(as in Fig. 1-3, 9, &c.) ; the name of Merenchyma having been
proposed for the looser tissues (as in Fig. 7, and in the pulp of
leaves and fruits generally), formed of rounded or ellipsoidal cells,
that is, where they do not mutually impress each other into plane
faces. But this distinction vanishes in the numberless intermediate
states ; and the name of Parenchyma is applied to both. That in
which the walls touch each other, more or less, and leave interven-
ing spaces where the ends or sides are rounded off, is termed by
Schleiden incomplete parenchyma ; and that in which the cells are in
perfect contact on every side, complete parenchy-
ma. The latter is regular, when the cells are
dodecahedral or cubical ; elongated or prismatic,
when extended longitudinally ; and tabular, when
cubical cells are much flattened; one kind of
which, called the muriform, because the laterally
compressed cells appear in the magnified section
like courses of bricks in a wall, is seen in the
silver-grain of wood (Fig: 192).

52. Proscncliyma is the general name for tissues
formed of elongated cells, especially those Avith
pointed or oblique extremities. Every gradation
may be traced between this and parenchyma. As
to length, such cells vary from fusiform, or spindle-
shaped, only three or four times longer than broad,
to tubular, and to tubes so long and narrow that
they are commonly called fibres. The most char-
acteristic form of prosenchyma is

53. Woody Tissue. {Pleurenchyma of Meyer and
Lindley. Woody Fibre of the older authors.)
Wood, which makes up so large a j)art of trees

FIG. 40 Some wood-cells of the Plane-t ee or Buttonwood, highly magnified : a, thin
spots in the walls, looking like holes ; on the right-hand side, where the walla are cut through,
these (b) are seen in profile.

4*

42 THE ELEMENTARY STRUCTURE OP PLANTS.

and shrubs, and some part of almost all ordinary herbaceous plants,
is wanting in Mosses and plants of still lower grades, such as
Lichens, Sea-weeds, and Fungi. That is, in the latter there is no
formation corresponding to the wood of higher plants, although
many of them exhibit, at least in certain parts, cells more or lesa
elongated, or even drawn out into tubes or hollow fibres of greater
length and tenuity than are those of ordinary wood ; such, for
instance, as the interlaced fibrous tissue of Lichens (Fig. 25).
Nor, on the other hand, does the proper wood of trees (except ii»
the Pine family) consist entirely of what is named woody tissue,
but has some other sorts variously intermingled with it. Indeed,
there are some trees whose wood is almost entirely composed
of true parenchyma, or of large dotted cells ; while in stone-fruits,
and many like cases, common parenchymatous cells acquire by in-
ternal deposit (41) a ligneous consistence, and even greater hardness
than ordinary wood (39). Nevertheless, the principal and charac-
teristic component of wood in general is thick-walled prosenchyma.
So that this takes the name of woody tissue even in the bark and
leaves, as well as in the trunk. Fig. 32 represents some of the
various elements of the wood of the Plane-tree. And Fig. 46 ex-
hibits three or four wood-cells from the same tree, more highly
magnified; the two right-hand ones cut through lengthwise, and
one of these, at the upper end, with a piece of another, also cut
across, to show the thickness of the walls.

54. This and the following figures likewise show how the wood-
cells are as it were spliced together, overlapping one another by
their tapering ends. Forming wood consists of oblong or prismatic
cells, with their ends nearly square or merely oblique: as these
young cells lengthen, the ends become more oblique, and push by
each other, or become wedged together. The wood-cells repre-
sented in Fig. 46 are about gVijij of an inch in diameter. Those of
our Linden or Bass-wood (a few of which are shown in Fig. 50, 51)
are rather larger, but not more than y^g- of an inch in diameter.*
Their size varies in different plants almost as much as ordinary cells
do, but they are usually much smaller than parenchyma, especially
in herbaceous plants. Perhaps the largest are found in the Pine
family, where they are of a peculiar sort, and are often as much

* Lindley states that the woody tubes of the Linden are as much as -jl^ of
an inch in diameter ; but I find none of anything like this size.

"WOODY TISSUE.

43

83 mta or 2 Itt °f an inch in diameter. The density or closeness of
grain in wood, however, does not depend so much on the fineness
of the wood-cells as upon the thickness of their walls. This is
much greater in proportion to their diameter than in ordinary
parenchyma, and, with their slenderness, and their very compact
arrangement into threads or masses which run lengthwise through
the stem, conspires to give the toughness and strength which charac-
terize those parts in which this tissue abounds. In old wood of the
harder kinds, the walls of the cells become so thick as almost to
obliterate the calibre (Fig. 198). The thickening is generally uni-
form, giving rise to no markings except the pits, or small thin spots,
already described (45), which appear like pores. These are of very
general occurrence, and are readily seen in the wood of the Plane-
tree (Fig. 32, a, 46). Markings of this kind are most conspicuous
in the Disc-bearing Woody Tissue {Glandular Woody Tissue of
Lindley) of the Pine Family, the nature of which has just been
explained (46). On account of their markings and their unusual
size, and because in the Pine family they make up the wood without
any admixture of ducts, these pecu-
liar wood-cells have been thought to
be rather a form of vascular tissue.
But in the Star-Anise much the
same kind of marking is found on
undoubtedly genuine woody tissue
(Fig. 47). In the Yew, on the
other hand, where the discs are
few, delicate spiral markings appear
(Fig. 48), showing a transition be-
tween the proper woody and the
vascular tissues ; as is seen by com-
paring the figure with that of a
spirally marked duct of Bass-wood, 47 48

Fig. 50, a. Here the thickening deposit is in two successive and
dissimilar layers ; the first, with circular vacuities, forming the discs,
while the second or innermost bears the spiral markings.

FIG. 47. Magnified woody tissue of Illicium Floridanum (longitudinal view), marked with
large dots, like the discs on the wood-cells of the Pine family.

FIG. 48 Magnified woody tissue from the American Yew (longitudinal view), some cells
showing delicate spiral lines only ; some showing the disc-like markings or dots of ordinary
Coniferae ; and others with both kinds of markings. Across the base is seen a portion of a
medullary ray.

44

THE ELEMENTARY STRUCTURE OF PLANTS.

oo. Bast Tissue, or Woody Tissue of the Liber. The bast or bass,
fibrous inner bark, or liber, as it is variously termed, of those plants

49 50 52 that have a true bark separable from

the avoocI of the stem, usually consists of
or contains much longer, very thick-sided,
and tougher, but more soft and flexible
cells, than those of the wood itself. These
properties are " probably given them that
they may possess the strength, combined
with flexibility, which their position near
the circumference of a branch renders
necessary." These especially adapt them
to the useful purposes they so largely
subserve for clothing and cordage. The
textile fibres of flax, hemp, &c. are all de-
rived from this woody tissue of the bark,
separated from the brittle cells of the
wood itself, and freed from the surround-
ing thin-sided parenchyma by macera-
tion (which soon decomposes the latter)
and by mechanical means.* The length
of bast-cells as compared with wood-cells
is exemplified in the accompanying figures
of the two, from our Basswood (Fig. 49

51 54 S3 ' V O

-51). The difference in the thickness
of the walls in this case is also great ; the cells of the soft wood hav-
ing rather thin walls even when old (Fig. 52), while those of the

* Cotton differs from linen in many respects, and is of a very different origin.
It consists of hairs, or long tubular cells, growing on the seeds of the plant.
These have very thin walls, which collapse so that the tube flattens, and then
twists spirally, which gives them a peculiar adaptation to be spun, or drawn out
together by torsion into a thread, contiguous fibres thus moderately clinging to
each other as they are drawn out. But they have not such thick and tough
walls as liber-cclls ; so a cotton fabric is not so heavy nor so durable as linen.

FIG. 49. One bast-cell, and part of another, from the bark of American Basswood. 50.
Some woody tissue from the wood of the same, with, a, upper end of a spirally-marked duct.
51. A separate cell from the wood All magnified to the same degree

FIG. 52 Transverse section of some wood-cells of the Basswood, highly magnified. 53.
Similar section of some bast-cells from the bark of the same tree, equally magnified.

FIG. 54, 55 Ends of bast-cells from the bark of the Leather-wood (Dirca palustris), mag-
nified.

VASCULAR TISSUE. 45

bast (Fig. 53) are so extremely thick-walled as almost to obliterate
the cavity. The disproportion in length is still greater in our
Leather-wood, which has a bark of extraordinary toughness, used
for thongs, while the wood is very brittle and tender. Its capillary
bast-cells measure from an eighth to a sixth of an inch in length,
with an average diameter of s^ of an inch (so that, if the whole
length of a cell, magnified as in Fig. 54, 55, were given, the figure
would be from a foot to a foot and a'half in length) ; while those of
the wood itself are only the hundredth of an inch long. Among the
bast-cells are found the longest cells which occur in any tissue. Still
the individual cells are by no means absolutely so long as they are
supposed, and have sometimes been stated, to be. Few are of such
length as those of the Leather-wood, above mentioned. According
to Mohl (Bot. Zeit. 1855, p. 876) there are few plants in which
they exceed the twelfth of an inch ; but he has found them an inch
long in Flax and in our common Milkweed (Asclepias Cornuti), and
somewhat longer in the Nettle.

56. Woody tissue runs lengthwise through the stem, root, or other
organ ; hence it is sometimes designated as Longitudinal Tissue, the

Vertical or Longitudinal System of the stem, &c. It shares this
name, however, with some other forms of tissue Avhich accompany
it, particularly in the wood. The cells which compose it agree
in exhibiting markings of some kind on their walls, and in being
larger than those of woody tissue : they are all more or less tubular,
or conspire to form tubes of considerable length, and hence they have
all been combined, in a general way, under the name of

57. Vascular Tissue or Vessels. Not to be misled by the name, it
should be remembered that these so-called vessels are mere modifica-
tions of cellular tissue, and are wholly unlike the veins and arteries
of animals. It is much better to call them ducts, a name appropriate
to their nature and office, and leading to no false inferences. Their
true nature is most readily shown in the largest and most conspicu-
ous kind, one which often exhibits unequivocal indications of its
cellular origin, viz.

58. Dotted Ducts, called also Pitted or Vasiform Tissue, Boihren-
chyma, &c. (Fig. 56, 57). They have likewise been termed Porous
Cells or Porous Vessels ; but the numerous dots that characterize

them are places which have not been thickened in the manner
already explained (41, 44), and not perforations, except in old cells,
where the primary membrane may be obliterated. Sometimes they

40

THE ELEMENTARY STRUCTURE OF PLANTS.

are continuous tubes of considerable length (Fig. 57) ; but occasion-
ally they exhibit cross-lines at certain intervals, plainly showing that
they are made up of a row of cells placed end to
end, and becoming a tube by the obliteration of the
intervening partitions (Fig. 56). In Fig. 32 some
dotted ducts (one of them exhibiting oblique parti-
tions or ends) are shown in place among the woody
tissue. It is in the wood that they commonly
abound. Being of greater calibre than any other
cells or vessels found there, they form the pores so
conspicuous to the naked eye on the cross-section
of many kinds of wood, such as of Oak, Chestnut,
56 57 and Mahogany, as well as the lines or channels
seen on the longitudinal section. Their size, compared with that of
the wood-cells in the wood of the Plane-tree, is shown both in longi-
tudinal and transverse section, in Fig. 31, 32.

59. Scalariform DllClS (Fig. 58, 59), differ from dotted ducts only
in the form of the markings, the thin spots being transversely elon-
gated instead of circular, and appearing like

cross-bars, which have been likened to the
rounds of a ladder, whence the name. This
is the more striking when the ducts are pris-
matic (by mutual pressure) and the cross-bars
occupy nearly the whole length of each side, as
in Fig. 58. Ducts of this sort abound in the
stems or stalks of Ferns. The markings are
often spiral in their arrangement; as is shown
in Fig. 59, by the way the duct tears into a
band. Ducts of this and of the foregoing sort,
where the markings are thin places, have been
named by Morren and Lindley Bothrenchyma,
meaning pitted tissue.

60. Reticulated, Annular, and Spiral Ducts (Fig. 60-65), on the

other hand (called Tracheae, from their resemblance to the windpipe,
or rather to the tracheae or air-tubes of insects), have been distin-
guished by Morren and Lindley under the general name of Trachen-
chyma. In these the markings, at least in most cases, are thicker

FIG. 56 Portion of a dotted duct from the Vine, evidently made up of a series of short cells.

FIG 57. Part of a smaller dotted duct, showing no appearance of such composition

FIG. 58. Scalariform ducts of a Fern, rendered prismatic by mutual pressure.

FIG 59 Similar duct of a Fern, torn into a spiral band.

VASCULAR TISSUE.

•17

places than the rest of the wall. They are elongated cells, or tubes
formed by the confluence of several cells into one, with the delicate
walls strengthened by the
deposition on their inner
surface of additional ma-
terial, in the form of bands,
sometimes branching and
forming network (the Re-
ticulated duct), as in the
middle of Fig. 60, or of
rings (the Annidar duct),
as in the middle of Fig.
61, or of a continuous spi-
ral thread (Fig. 62, 63), or
a number of such threads
(Fig. 64), thus forming the
Spiral duct or Spiral vessel. The coiled thread has been generally
thought to be solid. But Trecul, in a memoir already referred to
(42, note), insists that it is hollow, and it really appears to be so in
the thick threads or bands of certain cells in the wood of several
a b c d t sorts of Cactus, such as are shown in Fig. 40 - 43,
which are well adapted for the investigation of
this point. In the true Spiral Vessel the fibre is
so strong and tough, in comparison with the deli-
cate membrane on which it is deposited, that it
may be torn out and uncoiled when the vessel is
pulled asunder, the cell-wall being destroyed in
the operation. This is seen by breaking almost
any young shoot or leafstalk, or the leaf of an
Amaryllis, and gently separating the broken ends ;
when the uncoiled threads appear to the naked

FIG 60. A portion of a duct from the leafstalk of Celery ; the lower part annular ; the
middle reticulated, and the thread at the upper part broken up into short pieces

FIG. 61 Duct from the Wild Balsam or Jewel-weed ; the coils of the thread distant ; a
portion forming separate rings.

FIG. 62 A simple spiral vessel, torn across, with the thread uncoiling.

FIG. 63 Two such vessels joined at their pointed extremities.

FIG. 64 A compound spiral vessel, partly uncoiled, from the Banana.

FIG. 65. A bundle of spiral ducts from the stem of Prince's Feather (Polygonum orientale),
magnified : a, one composed of short cells and with the fibre closely coiled : the next, 6, is
composed of much longer joints, and ha? a very loose coil : c is short-jointed, and the fltre of
the loose coil is occasionally forked : d and e show no appearance of joints or partitions, and
the turns of the spiral fibro are still more remote.

48 THE ELEMENTARY STRUCTURE OF PLANTS.

eye like a fine cobewb. In stems furnished with pith, the spiral
vessels usually occupy a circle immediately around it. They occur
also in the veins of the leaves, and in all parts which are modifi-
cations of leaves. More commonly the coil is formed of a single
fibre, as in Fig. 62, 63 : it rarely consists of two fibres ; but not
uncommonly of a considerable number, forming a band, as in Fig.
64. Spiral vessels of the latter kind are to be found in an Aspara-
gus shoot, and are finely seen in the stems of the Banana. From
the Musa textilis of Manilla, of the same genus as the Banana,
these cobwebby fibres are said to be extracted in large quantities,
and used in the production of the most delicate of textile fabrics.

61. True spiral vessels, capable of uncoiling, occur in all plants
of the higher grades, but only in particular parts. Reticulated and
annular ducts abound in most herbaceous stems ; and every transi-
tion may be detected between the various kinds. Fig. 65 shows a
number of variations, such as may be seen at one view in the stem
of a Polygonum. Some have the fibre closely coiled ; in others the
turns are distant. Some are simple tubes, and apparently formed of
a single elongated cell : others show cross partitions, or vestiges of
them, and so are made up of a row of cells ; and if these be com-
pared with Fig. 39 - 43, &c, it will plainly appear that ducts of all
sorts are only a modification of ordinary cells. Even the longest
are of no great length ; very rarely are they above half an inch
long ; and they terminate by closed ends, like all other cells ; the
termination being either abrupt or more commonly conical or ob-
tusely pointed. In young parts the ducts, like other cells, contain
liquid, the ordinary juices of the plant: in older stems they are
filled with air, except when the whole tissue is gorged with sap,
which then finds its way into these also.

62. Interlaced Fibrilliform Tissue. This is quite as distinct from

ordinary cellular tissue, and as worthy of a special name, as any of
the kinds already described. It is the more worthy of notice,
from its near resemblance to some forms of animal tissue. It
consists of very long, much attenuated, simple or branching, fibre-
like cells, or strings of cells, inextricably entangled or interwoven
without order, so as to make up a loose, fibrous tissue. It is prin-
cipally met with in Fungi, Moulds, &c, where the cells are ex- .
tremely soft and destructible ; and in Lichens (Fig. 25), where it is
dry and much firmer. A remaining and a very ambiguous element
of vegetable fabric is

VESSELS OK THE LATEX.

■19

63. Laticifei'OllS Tissue ( Vessels of the Latex or Milky Juice.
Cinenchjma of Morren and Lindley.) This consists of long and
irregular branching tubes or passages, lying in no definite position
with respect to other tissue, and when young of such extreme tenu-
ity (their average diameter being less than the fourteen-hundredth
of an inch) and of such trans-
parency that the}r are hardly
visible, even under powerful mi-
croscopes, except by particular
manipulation. But their older
trunks are larger and more evi-
dent, when gorged with the milky
or other special juices which it is
their office to contain, and when
their sides are thickened by
the deposition of such matters. 67

Another peculiarity is, that they anastomose or inosculate, forming
a sort of network by the union of their branches, so that they freely
communicate with each other. In this respect, as well probably as
in the mode of their formation, they resemble the veins of animals.
But their branches do not proceed from larger trunks, and in turn
divide into smaller branchlets. They merely fork and inosculate
here and there, the branches being commonly as large as the trunk
before division. The articulations which they often present (as in
the upper part of Fig. 67) would seem to prove that they are formed
by the confluence of cylindrical cells. It is altogether most probable,
however, that they are not composed of cells at all ; but are, at first,
mere passages in the intercellular spaces, which in time are bounded
by walls formed by deposition from the contained fluid. Schultz,
who discovered these peculiar vessels and gave to them their present
name, describes a regular circulation of the juice they contain ;
which would make them still more analogous to the vessels or veins
of animals. But this has been shown to have no real existence.
There is merely a mechanical Aoav from any part under pressure, or
towards a place from which the latex is escaping, as from a wound.
Laticiferous vessels occur in the bark, especially in the liber, in the
leafstalks, and in the leaves, especially of those plants which have
a milky juice.

FIG 65 Vessels of the latex, ramifv ing among cellular tissue, in the Dandelion ; and 67,
older and larger vessels from the same plaut ; all highly magnified

5

50 THE ELEMENTARY STRUCTURE OF PLANTS.

G4. All the different kinds of tissue that enter into the composi-
tion of the plant have now heen described, and all (excepting the
doubtful latex-vessels) referred to the cell as their original. Every
plant, or each organ, consists at first of one or more cells of proper
cellular tissue. In many of the simpler vegetables, the cells multi-
ply in this primitive form solely ; and the fully developed plant con-
sists of parenchyma alone. But in all plants of the higher grades,
some of them early assume the forms of wood-cells and of ducts.
These modified cells always lie vertically in, or conspire to form,
bundles or cords that run lengthwise through, the stem or other
organ they occur in. They are associated with each other, and
together make up the woody parts, as in the wood proper, in the
liber or inner bark, and in the fibrous framework of the leaves.
Although the various kinds exhibit transitions through every man-
ner of intermediate forms, the whole, taken together, compose tissues
which are almost always manifestly different from the parenchyma
in which they are imbedded. It is convenient, therefore, to give
them a general name, and to denominate them, from their position,
the Vertical or Longitudinal System, or, from their nature, the
Fibro-vascidar or Woody System ; in contradistinction to the Hori-
zontal or common Celhdar System of the plant, consisting of paren-
chyma alone.

65. Intercellular System. The only exception to the statement
that all the vegetable tissues are formed of cells, is that of the
so-called vessels of the latex, which, according to the view now best
supported, are a secondary formation, resulting from the transuda-
tion of peculiar assimilated matters into the interspaces between the
cells ; and are therefore rather to be classed with other receptacles,
canals, or intervals that are found among or between the cells.
Some of these are accidental, or at least are irregular and indefi-
nite: such are the Intercellular Spaces or Passages, left
when the cells are not in contact throughout. Of the same char-
acter are the larger and irregular spaces in the lower stratum of
the tissue of most leaves (Fig. 7 and Fig. 221), and which form
irregular winding passages through which the air, admitted through
the stomates (70), freely circulates.

66. Ail'-Passages, however, are not always so irregular. The stalks,
and often the foliage also, of aquatic and marsh plants generally
abound with regular air-channels, of much greater diameter than
the cells of the tissue. These air-passages are symmetrically ar-

INTERCELLULAR AND EPIDERMAL SYSTEMS. • 51

ranged, and are as elaborately constructed as any proper organ can
be. They are built up of cells in a manner which may be compared
to a stack of flues or chimneys built of brick : they are constructed
upon a uniform plan in each species, and are evidently essential
parts ; plants which grow in water requiring a full supply of air
in their interior. Fig. 68 shows some of these air-passages in the
flower-stalk of Calla JEthiopica.

67. Receptacles of Special Secretions. These arise from the exuda-
tion of the proper juices of the cells into intercellular passages,
which are distended by the accumulation; or from the obliteration
of contiguous cells, so as to form cavities of considerable size. Such
are the turpentine-canals of the Pines, &c. ; the oil-cells of the
fruit of the Umbelliferae, and those in the rind of the orange and
lemon ; the latex-canals in Sumach, &c. Internal Glands, such as
those which form the translucent dots in the leaves of the Orange
and Myrtle, are little clusters of cells, filled with essential oil.

68. Epidermal System. In most plants, except of the lowest grades,
and those which grow under water, the superficial layer of cells is
different from the rest, and forms

69. The Epidermis, or skin of the plant. This consists of one or
more layers of empty thick-walled cells, cohering so as to form a
firm and close membrane, which may be detached from the subjacent
tissue. It covers all parts of the plant which are directly exposed to
the air, except the stigma. Its structure and office will be described
in the chapter on the Leaves. The epidermis forms a complete
and continuous covering, except that in certain parts, especially on
the lower surface of the leaves, it is perforated by a multitude of
small openings, called

FIG. 68 A magnified slice across part of the flower-stalk of Calla ^Kthiopica of our green-
houses, showing the large air-passages, built up of cells _: nearly in the centre, a bundle of
woody tissue is seen in cross-section.

52 THE ELEMENTARY STRUCTURE CKF PLANTS.

70. Stomates (Stomata) or Breathing-Pores. These have a peculiar
structure, the opening being guarded usually by a pair of thin-walled
cells, so arranged as to close or open according to circumstances.
They will also be illustrated in the chapter on the Leaves, to which
they more particularly belong.

71. Hairs are external prolongations of cells of the epidermis, con-
sisting either of single elongated cells, or of several cells placed end
to end, or of various combinations of such cells. They are simple
or branched, single or clustered (stellate, &c), and exhibit the
greatest variety of forms. In what are called Glandular Hairs, or
Stalked Glands^, the upper cell or cluster of cells has a peculiar
structure, and elaborates peculiar (usually odorous) products, such
as the fragrant volatile oil of the Sweetbrier.

72. Glands. This name is applied to any secreting apparatus, and
especially to superficial appendages of the epidermis which elaborate
odorous or other products.

73. StingS, or Stinging Hairs, such as those of the Nettle, gener-
ally consist of a rigid and pointed cell, borne on an expanded base,
or gland, which secretes an irritating fluid.

74. Bristles (Setts) are rigid, thick-walled hairs, usually of a single
cell. But the name is likewise given to any similar bodies, of what-
ever nature.

75. Prickles are larger and indurated, sharp-pointed processes of the
epidermis or the bark (but not of the wood) ; such as those of the
Rose and Blackberry.

76. Scurf, or Lepidote, Scale-like Hairs, are flattened, star-like
clusters of cells, united more or less into a sort of scale, which is
fixed by its centre to the epidermis. They are well shown in the
Oleaster, Shepherdia, and most silvery leaves like theirs. Our
species of Vesicaria exhibit beautiful gradations between these and
star-shaped (stellate) hairs.

Sect. IV. Of the Contents op Cells.

77. These comprise all the -products of plants, and also the
materials plants take in from which these products are elaborated.
To treat of them fully would anticipate the topics which belong to
the chapter on Nutrition. Some of the contents of cells, however,
have already been mentioned, in the account of their production and

SAP, SUGAR, ETC. 53

growth (27-40) : others require a brief notice here, especially two
solid products which are of nearly universal occurrence and of
great importance in the vegetable economy, namely, Chlorophyll and
Starch.

78. The same cells contain liquids, solids, and air, at different
ages. Growing and vitally active cells are filled with liquid (at
least while vital operations are carried on), namely, with water
charged more or less with nutritive assimilated matters, the pre-
pared materials of growth- (11, 27). Any air they may contain at
this period is, for the most part, held in solution. Completed cells
may still be filled with liquid, or with air, or with solid matter only.
The liquid contents of the vegetable tissues, of whatever nature or
complexity, are generally spoken of under the common and some-
what vague name of

79. Sap. In employing this name we must distinguish, first,
Crude Sap ; the liquid which is imbibed by the roots and carried
upwards through the stem. This is water, impregnated with certain
gaseous matters derived from the air, and with a minute portion of
earthy matter dissolved from the soil. It is therefore inorganic (12).
But, as it enters the roots and traverses the cells in its ascent, it
mingles with the liquid or soluble assimilated matters which these
contain, so that unmixed crude sap is never met with in the plant.
On reaching the leaves, a part of the inorganic materials of the
ascending sap are transformed, under the influence of light, into
organizable or assimilated matter ; and the liquid, thus charged with
the prepared materials of growth, is now Elaborated Sap. The
nutritive matter of the elaborated sap is of two general kinds :
1. The ternary, which consists of only the three elements, carbon,
hydrogen, and oxygen ; and 2. The quaternary, which consists of
four elements, viz. of nitrogen in addition to tho^e just mentioned.
Sugar and dextrine, or dissolved starch, are representatives of the
first class ; and these have, nearly the same chemical composition as
cellulose or cell-membrane. Protoplasm or proteine represents the
second class (27).

80. Sugar (of which there are two distinct kinds, Cane and Grape
Sugar) is the most soluble form of ternary organizable matter.
Though sometimes crystallized as an excretion in the nectaries of
flowers, yet in the plant it exists only in solution. It abounds in
growing parts, in many stems just before flowering, as tho-re of the
Sugar-cane, Maize, Maple, &c, in pulpy fruits, and in seeds when

o*

54 THE ELEMENTARY STRUCTURE OF PLANTS.

they germinate ; and is the appropriate prepared material for the
plant's nourishment and growth. Dextrine is a substance inter-
mediate in nature between sugar and starch.

81. Starch {Farina, Fecula) is one of the most important and
universal of the contents of cells, in which it is often accumulated
in great quantity, so as to fill them completely (Fig. 70) ; as in

farinaceous roots,
seeds, &c. It oc-
curs in the pa-
renchyma of al-
most every part
of the plant, ex-
69 70 cepting the epi-

dermis : but while chlorophyll is nearly restricted to the superficial
parts, directly exposed to the light, starch is most abundant in inter-
nal or subterranean parts, concealed from the light, as in roots and
tubers, the pith of stems, and seeds. Starch consists of transparent
oval or rounded grains, sometimes becoming angular by mutual
pressure, as in rice. The size of the grains varies extremely in
different plants, and even in the same cell ; as in the potato, where
the larger grains measure from -jjg- to -g-^-j of an inch in their larger
diameter, but the smallest only -j-^1,,^ of an inch. In wheat-flour the
larger grains are ^^ to -g-^ of an inch in diameter. And the
largest starch-grains known are ^<j of an inch long. Indeed, from
their formation, we Tnight expect that their bulk would vary con-
siderably. The mode of their formation is indicated by the peculiar
markings, by which most starch-grains may be recognized ; namely,
by the dot or darker point which is seen commonly near one end of
the grain, and the fine concentric lines drawn around it. These are
best seen in starch from the potato, one of the most characteristic
forms and easiest to be examined, under a magnifying power of
from 250 to 500 diameters (Fig. 69). The chemical composition
of starch is exactly the same as that of cellulose (27) ; and the
grains are solid throughout, but their interior usually softer or more
gelatinous. The lines evidently show that starch-grains consist of
concentric layers, of different density, successively deposited on an

FIG 69 Two cells of a potato, with some contained =tarch-grains, highly magnified ; one
of the cells contains a few cubical crystals also.

FIG 70 A minute portion of Indian meal, strongly magnified ; the cells absolutely filled
with grains of starch.

STARCH, AMYLOID. 55

original nucleus. The layers are commonly much thicker on one
side than the other, so that the dot or nucleus, which all the lines
surround, becomes very eccentric. Starch-grains lie loose in the
cell where they are formed, and are usually separate and simple.
But occasionally two or more small grains are combined by new
layers into one, and in some plants they are regularly united into a
cluster or compound grain, as in West-India Arrowroot, the corms
of Colchicum and Arum, and the rootstocks of the Water-Lily
(Nymphrea) and "Water-Shield (Brasenia). In the latter the grains
are oblong or club-shaped, and remarkably large. Starch-grains are
nearly uniform in the same plant or organ, and of very different
appearance in different plants : so that the smallest quantity of
starch from the potato, wheat, rice, maize, arrow-root, &c, may at
once be distinguished under the microscope. In this way adultera-
tions of arrow-root, &c. may be detected. The outer layers of
large and well-developed starch-grains (such as those of the potato)
are denser than the inner : consequently, each grain is marked by a
dark cross when viewed by polarized light. Starch is unaffected
by cold water; but hot water is absorbed by it; the inner part of
the grain softens first and swells, inflating the denser superficial
portion into a large sac, which may at length burst or be dissolved.
It thus forms a jelly with boiling water, but is not really soluble in
it When truly dissolved, it is no longer starch, but, by a slight
change in its character, it is changed into dextrine (80). The
chemical test of starch is iodine, winch turns it blue.

82. Starch is the form in which nourishing matter is stored up in
the plant for future use ; in which respect it may be likened to the
fat of animals. It is the ready-prepared material of vegetable fabric,
— the same as cellulose in a particular and more soluble fonn, —
accumulated in the cells of certain parts as a provision for future
growth. When about to be used, the grains are dissolved in the
plant at the natural temperafure ; that is, the starch is converted into
dextrine, which differs chiefly in being soluble in cold water, and this
changes into sugar, which is still more soluble ; and thus a sirup is
formed, which the sap dilutes and conveys to the adjacent parts, or
to wherever growth is going on.

83. Amyloid (of which Bassorin, Salep, and Pectine are apparently
modifications), which in solution is Vegetable Jelly, is intermediate in
character between starch, dextrine, and eclhiloe, and has nearly the
properties of starch, when this has been altered by hot water. It

56 T1IK ELEMENTARY STRUCTURE OF PLANTS.

abounds in the almond, bean, and some other esculent seeds, in the
tubers of Orchises (as Salep, &c), and forms the principal substance
of many sea-weeds, such as the Carragheen Moss (Chondrus crispus),
from which jelly is obtained for culinary purposes. When dry, it is
horny or cartilaginous, and lines the cells ; when moist, it swells
up, becomes gelatinous, and is capable of being perfectly diffused
through cold water. We have it as an excretion in Gum Traga-
canth. True gums, such as Gum Arabic, are states of nearly the
same substance, and are likewise formed only as excretions.

84. Fixed Oils belong to the class of ternary products, but they
contain little oxygen, and some of them none at all. The fatty oils
take the place of starch in the seeds of many plants (as in flax-seed,
walnuts, &c), and of sugar in some fruits, such as the olive. They
also occur in the herbage of most plants.

85. Wax is a product of nearly the same nature as the fixed oils,
only it is solid at the ordinary temperature. It occurs as an excre-
tion, particularly on the surface of leaves and fruits, forming the
bloom or glaucous surface which repels water, and so prevents such
surfaces from being wetted. It forms a thick coating on some fruits,
as the bayberry. Wax also exists in all herbage, being one of the
components of the green matter of plants (02).

8G. Vegetable Acids. Tartaric, Citric, and Malic Acids are the
principal kinds; they are found in the herbage of those plants which
have a sour juice, such as Sorrel and the Grape- Vine. They are
ternary products, with a larger proportion of oxygen than staich,
sugar, and the like. They do not appear to play any leading part
in vegetation. They seldom exist in a free state, but are combined
with the alkaloids, and with the inorganic or earthy alkalies (Potash,
Soda, Lime, and Magnesia), which are introduced into plants from
the soil with the water imbibed by the roots. The more soluble
salts thus produced are found dissolved in the sap ; the more insolu-
ble are frequently deposited in the cells, either as an incrustation of
their walls, or in the form of minute crystals. When these crystals
contain a vegetable acid, it is almost always Oxalic Acid. This is
an almost universal vegetable product, and is a binary body (that is,
consists of two elements only, carbon and oxygen), differing from
carbonic acid in ultimate composition only in having a little more
oxygen. Hydrocyanic or Prussic Acid is one of the special pro-
ducts peculiar to certain plants, and of "s cry dilferent composition,
containing a large portion of nitrogen.

OILS, ACIDS, ALKALOIDS, KTC. 57

87. Tanilin cr Tannic Acid, which most abounds in older bark, is
probably a product of the oxidation or commencing decomposition
of the tissues. So, also, Humus, Ilumic Acid, Ulmine, Ulmic Acid,
and the numerous related substances distinguished by the chemists,
are products of further decomposition of vegetable tissue, rather
than true products of vegetation.

88. Essential Oils, Turpentine, Caoutchouc, &c. These are some of

the Proper Juices of plants, peculiar to certain plants, and occurring
under a great variety of forms in different species. It is not known
that they are of any account in vegetable growth or nutrition. They
undergo changes on exposure to the air, and become resins, gums,
&c. They are apt to be accumulated in intercellular cavities, or to
be excreted from the^ surface of the plant. Not knowing of what
use they are to the vegetable, we are inclined to regard them as of
the nature of excretions. Caoutchouc exists in the form of minute
globules, diffused as an emulsion in the milky juice of plants, of
various families. The original India-Rubber of the East Indies is
the milky juice of a species of Fig. That of South America, now
so largely used for a great variety of purposes, comes from certain
trees of the Euphorbia family. It equally occurs in the juice of our
Milkweeds or Silkweeds. Gutta-Percha is a similar product of the
milky juice of a Sapotaceous tree of Borneo.

89. The quaternary class of products (viz. those which consist of
the four elements, carbon, hydrogen, oxygen, and nitrogen, 79) are
of two kinds, the special and the general. The former are peculiar
to certain plants ; the latter are universal products of vegetation.
Examples of the special kind are found in Hydrocyanic or Prussic
Acid, already mentioned (86), and the

90. Alkaloids, such as Morphine, Strychnine, and Quinine. These
are principally formed in the bark and the leaves. We do not know
that they bear any part in vegetation, nor of what use they are to
the plant. In these substances reside the most energetic properties
of the vegetable, considered as to its action on the animal economy,
the most powerful medicines, and the most virulent poisons. That
they are of the nature of excretions may be inferred from the fact,
that a plant may be poisoned by its own products, introduced into its
ascending sap.

91. The principal general quaternary product of plants is Pro-
teine, the nature and uses of which have already been explained
(27, 79). ' As it exists in living cells in a liquid or gelatinous

58 THE ELEMENTARY STRUCTURE OF TLANTS.

state, it receives the name of protoplasm. Besides lining the Avails
of living cells and forming the nucleus, it is also a component of one
of the most important vegetable products, viz.

92. Chlorophyll, or, as the name denotes, Leaf-green, the substance
which gives the universal green color to the leaves and herbage.
This is formed principally in parts exposed to the light, such as the
green bark, and especially the leaves. It generally occurs in the
form of minute soft granules, either separate or in clusters, which
lie free in the cells (Fig. 71), or adhere loosely to their sides. In
some common Confervas the chlorophyll takes the form of rows of
granules, or of continuous bands, often spiral in form. The exact
composition of chlorophyll is still unknown. The green coloring
matter makes only a small part of the bulk of the grains. It may
be dissolved out by alcohol or ether, leaving a' colorless mass, which,
as it is turned yellow by iodine, evidently contains nitrogen. The
green matter is found to consist partly of wax, and partly of a pecu-
liar quaternary substance allied to indigo.

93. Earthy Incrustations. As the roots naturally take in some
earthy matters, dissolved in the water they absorb from the soil,
these necessarily accumulate in the cells of the plant. The siliceous
and calcareous matters, being very sparingly soluble, are usually
deposited on the Avails of the cells as an incrusting lining, or else
are incorporated into its substance along with the organic thickening
deposit (41). This earthy part of vegetable fabric may be brought
to vieAv by carefully burning a piece of a leaf or any other organ, —
Avhich decomposes and drives off all the vegetable matter, — and then
examining the ashes by the microscope. These are mineral matter,
and when undisturbed they will be found to have copied the shape
and all the minute markings of the cells, like casts. In the Diato-
maceae, — a family of microscopic and ambiguous plants of the sim-
plest structure, — a great part of the thickness of the cell-wall is
silex, and consequently indestructible by decay. So that the forms
of these minute organisms are preserved indefinitely, after the de-
composition of the organic structure ; their silicious remains accu-
mulating at the bottom of the water in which they lived, to such
extent as to produce immense strata in many places, their forms and
markings so perfectly preserved for ages that the species may be
nearly as Avell characterized from these casts as from living indi-
viduals. Earthy matters also occur in the cells of plants in the
form of microscopic

CRYSTALS OR RAPHIDES.

59

94. Crystals, or Rapllides (Fig. 71-78). These exist in more or
less abundance in almost every plant, especially in the cells of the
bark and leaves, as well as in the wood and pith of herbaceous
plants. In an old stem of the Old-man Cactus (Cereus senilis), the
enormous quantity of eighty per cent of the solid matter left after
the water was driven off was found to consist of these crystals. In
the thin inner layers of the bark of the Locust, each cell contains a
single crystal, as is shown in Fig. 75. Professor Bailey, who has de-
voted particular attention to this subject, computed that, in a square
inch of a piece of Locust-bark, no thicker than ordinary writing-paper,
there are more than a million and a half of these crystals. There
is frequently a group of separate crystals in the same cell, or a con-
glomerate cluster, as in Fig. 76. The most common form is that
of a long and narrow four-sided prism, so slender that it resembles
a needle (Fig. 71-73). Such crystals were accordingly called
It aphides, i. e. needle-shaped bodies, — a name which has been ex-
tended to include all crystals in plants, of whatever shape. When
the crystals are needle-shaped, they usually occur in large numbers
in each crystal-bearing cell, packed together in a bundle. These

FIG 71. Raphides, or acicular crystals, from the stalk of the Rhubarb : three of the cells
contain chlorophyll, and two of them raphides

FIG 72. Kaphides of an Arum, contained in a large cell ; and 73, the same, detached from
the surrounding tissue, and discharging its contents upon the application of water

FIG. 74 Crystals from the base of an onion, one of them a hemitrope or double.

FIG. 75. Crystals of the inner bark of the Locust.

FIG 76. A glomerate mass of crystals from the Beet-root.

FIG 77.78 Crystals from the bark of Hickory. Figures 73-78, and also 69, are from
sketches kindly supplied by the late Professor Bailey of West Point.

60 THE GENERAL DEVELOPMENT OE PLANTS.

may be readily found in the stalks of tlie Rhubarb, the Four-o'clock,
the Arum or Indian Turnip, and the Calla. In the latter plants, a
crystal-bearing cell in the leaf may often be detached entire from
the surrounding tissue : when moistened, it absorbs water by endos-
mosis, becomes distended, and may sometimes be seen to eject its
crystals one by one, in a curious maimer, through a minute perfora-
tion at one or both ends (Fig. 73). As to their composition, these
crystals more commonly consist of oxalate of lime; but those of car-
bonate, sulphate, or phosphate of lime are not unfrequent.

95. CystolitllCS are a peculiar structure composed of crystalline
mineral and of vegetable matter combined, of common occurrence in
the leaves of the Fig, Hop, Mulberry, and all the Nettle family,
just beneath the epidermis. They are globular or club-shaped
bodies, or of various other forms, usually hanging by a short stalk
in an enlarged cell : their principal mass is found to be cellulose ;
but their surface is studded with crystalline joints of carbonate of
lime.

CHAPTER II.

OP THE GENERAL DEVELOPMENT AND MORPHOLOGY OP PLANTS.

96. Having ascertained what vegetable fabric consists of, we are
prepared to consider how these organic materials, the cells, are com-
bined to constitute a vegetable, what the parts or organs of plants
are, how they are related to each other, and how they live, grow,
and perform the work of vegetation. Viewing plants as individual
beings, we may now proceed to study their Organography or Mor-
phology (3).

97. Plants occur under the greatest diversity of forms. Some
kinds are of the utmost simplicity ; and many of these are so minute,
that separately they are invisible to the naked eye, and become
apparent only by their aggregation in vast numbers. Others are
highly complex in structure, and may attain a great size, such as
gigantic trees, some of which have flourished for a thousand years
or more. But each plant or tree, however vast or complex it may
become, commenced its existence as a single vegetable cell, by the

PLANTS OF THE LOWER GRADE. 61

multiplication of which the whole fabric was built up. All our or-
dinary herbs and trees, however, even while in the seed, have already
passed beyond this stage, and consist at this time of a mass of cells,
more or less distinctly wrought into the form of a plantlet ; while
the germs of plants of a lower grade, at the time of their separation
from the parent plant, are each no more than a single cell. Cells of
this kind, destined to give rise to new individuals (i. e. for reproduc-
tion), are called Spokes. The name spore is from a Greek word,
meaning the same as seed.

98. Plants may be distinguished, therefore, into two great Series
or Grades, a lower and a higher ; — the lower or simpler grade con-
sisting of those plants which directly spring from single cells or
spores ; the higher grade, of those which spring from seeds.

Sect. I. Plants of the Lower Grade; their Develop-
ment from the Cell.

99. This grade includes the simplest and minutest plants, and
also many which attain a great size, and exhibit no small complexity
of structure, such as Tree Ferns (Fig. 100), for instance. The
very lowest kinds not only begin their existence as single cells, but
continue so throughout their whole growth. The most simple possi-
ble form of vegetation therefore consists of

100. Plants Of a Single Cell. In these minims of the vegetable
world, the plant is reduced to its lowest terms : the plant and the
cell are here identical. The cell constitutes an entire vegetable xoith-
out organs, imbibing its food by endosmosis (40) through its walls,
assimilating tins "food in its interior, and converting the organizable
products at first into the materials of its own enlargement or growth,
and finally into new cells, which constitute its progeny. Thus we
have an epitome of all that is essential in vegetation, even on the
largest scale ; namely, the imbibition of inorganic materials ; their
assimilation; their application to the growth of the individual, or
nutrition ; and the formation of new individuals, or reproduction.
Every stream or pool of water abounds with such plants, often in
great variety. Simple as these plants are, they are by no means
restricted to one monotonous pattern : perhaps they present as great
diversity of form as do the kinds of ordinary vegetation, all hough
from their minuteness they are mostly invisible to the naked eye.

6

THE GENERAL DEVELOPMENT OE PLANTS,

The admirable memoirs of Nageli and of Braun upon One-celled
Plants, and the works of Ralfs, Kutzing, Thvvaites, &c. upon the
Desmidiaceae and Diatomaceae, illustrate a great variety of forms.
The simplest possible case is that of

101. Plants of a Single Globular Cell:

79 81 82 •> "

that is, of a cell which grows equally in
every direction, and therefore retains the
original form. The microscopic plant
known as giving rise to the phenomenon
of red snow furnishes a good illustration
of the kind (Fig. 79, 80) : and so does a
more common species, Protococcus cru-
entus, which forms dull-crim.-on patches, resembling blood-stains, on
the northern side of damp rocks or old walls. Each sphere is a
single cell, which, quickly attaining its growth, produces (probably
by division of the contents) a number of free cells in its interior.
These escape by the decay of the Avails of the mother-cell, grow
speedily into similar cells or plants themselves, giving rise to another
generation, and perish in their turn. Fig. 81 represents another
and similar one-celled plant ; and Fig. 82 and 83 show its mode of
propagation, namely, by division of the whole living contents into
two portions, and these again into two, these four globular masses
soon acquiring a wall of cellulose, and becoming so many distinct
cells or plants ; — the whole process admirably illustrating a com-
mon mode of cell-multiplication (36). Indeed, another microscopic
plant of the kind, very common in shallow pools at the beginning of
spring, was taken as the readiest example of this multiplication of
cells (Fig. 18 - 22). This propagation causes the destruction of the
mother-plant in each generation, all its living contents being em-
ployed in the formation of the progeny, and its effete wall obliter-
ated by softening or decay, and by the enlargement of the contained
cells. Thus the simplest vegetation goes on, from generation to
generation. The softened remains of the older cells often accumu-
late and form a gelatinous stratum or nidus, in which the succeeding
generations are developed, and from which they doubtless derive a

FIG. 79 Several individuals of the Red-Snow Plant (Protococcus nivalis) magnified 80.
An individual highly magnified, showing more distinctly the new cells or spores formed with-
in it

FIG. 81 An individual of Chroococcus rufescens, after Ndgcli. much magnified. 82 A
more advanced individual, with the contents forming two Lew cells by division. 83 Another,
with the contents divided into four new cells.

OF THE LOWER GRADE.

part of their sustenance, — just as a tufted Moss is nourished in part
from the underlying bed of vegetable mould which is formed of the
decayed remains of its earlier growth. Other one-celled plants
enlarge in one direction more than in any other, so becoming oval
or oblong, and making a transition to a somewhat higher grade of
vegetation, viz.

102. Plants of a Single Elongated Cell. Such plants may be con-
ceived to bear the same relation to the foregoing, that ducts (57)
and wood-cells (53) do to cells of parenchyma (51). For an ex-
ample we may take any species of Oscillaria

(Fig. 84) ; a form of aquatic vegetation of mi-
croscopic minuteness, considered as to the size
of the individuals ; but these rapidly multiply
in such inconceivable numbers, that, at certain
seasons, they sometimes color the surface of
whole lakes of a green hue, as suddenly as
broad tracts of alpine or arctic snow are red-
dened by the Red-Snow Plant. If the trans-
verse markings of some Oscillarias answer to
internal partitions, then they make a transition
between one-celled plants and those formed of
a row of cells. — Since cells which form part of
the fabric of vegetables are sometimes branched
(38), we should naturally expect to find, as the
next step in the development,

103. Plants of an Elongated and Branching Cell. Good ex.
amples of the sort are furnished by the species of Vaucheria, which
form one kind of the delicate and flossy green threads abounding in
fresh waters, and known in some places by the name of Brook-silk.
These, under the magnifying-glass, are seen to be single cells, of
unbroken calibre, furnished here and there with branches (Fig. 89).
The branches are protrusions, or new growing points, which shoot
forth by a sort of budding, and have the power of continuous growth
from the apex. In Bryopsis (Fig. 91), a beautiful small Sea-weed,
the branches are much more numerous and regularly arranged;
their cavity is continuous with that of the main stem, if we may
so call it : in other words, the whole plant, which is by no means
minute, consists of a single, repeatedly many-branched cell. And
in Codium, another genus of marine Algne, we have an indefinitely

FIG 84. Two individuals of Oscillaria spiralis, magnified ; one with an extremity cut off".

ci

THE GENERAL DEVELOPMENT OF PLANTS,

ramified cell, intricately interlaced or compacted, and forming dense
masses of considerable size and of definite shapes.

83 a 90

6\J)

104. While in these cases the ramifications of the cell imitate, oi
as it were foreshadow, the stem and branches of higher organized
plants, we have in Botrydium (Fig. 88) a cell whose ramifications'
resemble and perform the functions of a root. This consists of an
enlarged cell, which elongates and ramifies downwards, the slender
branches penetrating the loose and damp soil on which the plant grows,
exactly in the manner of a subdivided root. Meanwhile, a crop of
spores or rudimentary new cells is produced, by original cell-forma-
tion (29), in the liquid contents of the mother-cell: these, escaping
when that decays or bursts, grow into similar plants, in the manner
shown by Fig. 86, 87. The spores by which Vaucheria is propagated
originate in a somewhat different way. When about to fructify, the
apex of a branch enlarges, its green contents thicken, separate from
those below, condense into a rounded mass, which acquires a coat of
protoplasm (Fig. 89, a) : the sac in which it was formed soon bursts
open, and the new-born spore escapes into the water (Fig. 90). It
moves about freely for some hours (678), when a coat of cellulose is
formed upon its surface, converting it into a true cell, which soon

FIG 85-87. Botrydium Wallrothii in its development, and with new cells forming within ;
after Kutzing: 85. the cell still spherical: 86, pointing into a tube below: 87, the tube pro.
longed and branched : all much magnified.

b'lG 88 Botrydium argilUiceum, after Endlicher ; the full-grown plant, magnified

FIG 89 Vaucheiia clavata, enlarged; o, a spore formed in the enlarged apex of that
branch 90 End of the branch, more magnified, with the spore escaped from the burst apex.

FIG. 91. Brjopsis plumosa ; sumir.it cf a stem with its brar.chlets, much enlarged.

OF THK LOWER GRADE.

65

grows by elongating into a thread, one end of which fixes itself to a
stone or some other solid body, while the other grows first into a
simple tube, and then sends off branches like its parent. In this
way, a plant composed of a single cell imitates not obscurely the
upward and downward growth (the root and the stem) of the more
perfect plants, or when cells like these, whether simple or branched,
form cross-partitions as they grow, in the maimer of the Conferva
(Fig. 15) used to illustrate this mode of cell-multiplication, they give
rise to

105. Plants Of a Single Row of Cells, Most of the thread-like green
Algae (Confervea;), which abound in pools and brooks, are of this
sort. So are the
Moulds or Mildew
Fungi, of which
three kinds are here
represented ; viz.
the Bread-Mould
( Fig. 92 ), and
the Cheese-Mould
(Fig. 93), which
live upon dead or-
ganic matter; and
a species of Botrytis (Fig. 94). The latter, and other Moulds of
the same or of other kinds, feed upon the juices of living plants, and
even animals, where they commit great ravages. The too well-
known potato-disease, for example, is probably caused by the attack
of a species of Botrytis ; a similar species has long been known as
the cause of the muscardine, a fatal malady of silk-worms, and the
malady which lias for several years destroyed a great part of the
grape-crop in Europe is caused by another parasitic plant of the
same simple structure. The accompanying figures show only the
perfect state of these troublesome little plants, or rather their fructi-
fication. Their vegetation consists of long and branching threads
(of which a small portion only is represented at the base), which
penetrate and spread widely and rapidly through the vegetable, ox-
other body they live on, and feed upon its juices. At length they
break out upon the surface, and produce countless numbers of

FIG. 92-94. Three kinds of Mould, magnified. 92. The Hread-Mould (Mucor, or Asco-
phora). 93. The Cheese-Mould (Aspergillus glauous). 94. liotijtis Bassiaua, the species
which attacks silk-worms, &c.

6*

66 THE GENERAL DEVELOPMENT OF PLANTS,

spores (97), or minute rudimentary ceils, which are detached from
the parent plant and serve the purpose of seeds. The spores are
in some cases produced (probably by original cell-formation), in an
enlarged terminal cell, as in the Bread-Mould (Fig. 92,,; while in
other cases they are naked, and arise from cell-division, as in Fig.
93, 94.

10G. Plants of this simple structure (belonging chiefly to the
lower Algoe and Fungi) are almost as various in form and numerous
in species as are the higher kinds of vegetation. Some consist of a
single jointed thread ; others are excessively branched ; and some-
times the branches are interlaced or compacted to form masses or
strata of considerable size. Some of them present little or no dis-
tinction among the cells they consist of, each cell performing the
same office as any other, and each capable of producing spores or in
some way serving for reproduction ; such may well be regarded
as rows of one-celled plants, more or less united. But more com-
monly, even in the simplest vegetable forms, the work which the
plant has to perform is divided, some parts serving for vegetation or
nutrition, and others for reproduction, as we see is the case with the
Moulds, &c. Even a one-celled plant may begin to have organs, or
parts adapted to special purposes, as is well shown by Botrydium
and Vaucheria (Fig. 85-90). As we ascend in the scale of Aege-
table life, more and more specialization will be found at every step.

107. A slight change in the way the cells multiply, namely, the
formation of partitions in two directions instead of only one, intro-
duces the next advance in vegetable development, giving rise to

■b

H

US

ii

law

«es&

108. Plants of a Single Plane or Layer of Cells. Figures 18 - 22 show

how a plant of a single spherical cell may multiply, by repeated

TIG. 95. A piece of Delesseria I.eprieurei, from Hudson River, of twice the natural size.
95. A portion of the whole breadth of the same, more magnified, to show the cellular struc-
ture. The cells have thick gelatinous walls ; Uose in the middle are elongated, those towards
the margins rounded. 9". A small portion still more magnified.

OF THE LOWER GRADK. 67

division, into two, four, and sixteen such plants, and so on. But if
these cells had merely remained in connection as they multiplied,
they would have composed one plant, consisting of a stratum of cells.
This is just what we have in the Dulse or Laver (Ulva, &c.) and
some other simple leaf-like Algre of various kinds, such, for example,
as that illustrated in Fig. 95 - 97. When the Avhole hody of a plant
is thus expanded and leaf-like, it forms Avhat is called a Fkond.

108". Not only Sea-weeds, hut many Liverworts and Lichens,
grow in this way. (In Lichens, &c, the expanded hody usually
takes the name of Tiiallus.) In most cases, however, such plants
are composed of more than one layer of cells, or of a considerahle
number of layers. And those of thread-like forms, resembling naked
stems and branches, in all the coarser and in some very delicate
kinds, are made up, like the parts of ordinary vegetables, of several
thicknesses of cells ; that is, they are

109. Plants of a Solid Tissue of Cells, formed by cell-multiplication
through division taking place in more than two directions. Sea-
weeds, Lichens, and other plants of the lowest orders, forming in
this way a tissue of cells, generally exhibit either leaf-like or stem-
l.ke shapes, but seldom if ever do they present both in the fame
plant. They may resemble leaves, or they may resemble stem and
branches, or display a variety of forms intermediate between stem
and leaf. But it is only when we come to the highest tribe of
Liverworts, and to the true Mosses, that the familiar type of ordinary
vegetation is realized in

no. riants with a Distinct Axis and Foliage; that is, with a stem

which shoots upward from the soil, or whatever it is fixed to, or
creeps on its surface ; which grows onward from its apex, and is
symmetrically clothed with distinct leaves as it advances. All these
lower vegetables, of whatever form, imbibe their food through any
or every part of their surface, at least of the freshly formed parts.
Their roots, when they have any, are usually intended to fix the
plant to the rock or soil, rather than to draw nourishment from it.
The strong roots of the Oar-weed, Devil's Apron (Laminaria), and
other large Sea-weeds of our coast, are merely hold-fasts, or cords
expanding into a disc-like surface at the extremity, which by their
adhesion bind these large marine vegetables firmly to the rock on
which they grow. Mosses also take in their nourishment through
their whole expanded surface, principally therefore by their leaves;
but the stem; aho shoot forth from time to time delicate rootlets,

68

TIIK GENERAL DEVELOPMENT OF PLANTS.

composed of slender cells which grow in a downward direction, and
doubtless perform their part in absorbing moisture. A Moss, there-
fore, is like an ordinary herb in minia-
ture, and exhibits the three general
Organs ov Vegetation, viz. Jiooty
Stem, and Leaves.

111. Cellular and Vascular Plants.

"While the Mosses emulate ordinary
herbs and trees in vegetation and ex-
ternal appearance, they accord with
the lowest kinds of plants in the sim-
plicity of their anatomical structure.
They are entirely composed of cellu-
lar tissue strictly so called, chiefly in
the form of parenchyma (51) ; at least
they have no distinct vessels or ducts
(57) and no true wood in their com-
position. The Mosses, along with the
Lichens, Algaj, Fungi, &c, were there-
fore denominated Cellular Plants
by De Candolle. All plants of higher
grade, inasmuch as vascular and woody
tissues enter into their composition,
when they are herbs as well as when
they form shrubs or trees, he distinguished by the general name of
Vascular Plants.

112. The strength which woody tissue imparts (54) enables
plants in which it abounds to attain a great size and height ; while
Mosses and other cellular plants are of humble size, except when
they live in water, in which some of the coarser Sea-weeds do indeed
acquire a prodigious length. Although true Mosses have no wood
in their composition, yet the so-called Club-Mosses have. So also
have the Ferns, the highest organized family of the lower grade of
plants ; and although these are mostly herbs, or else plants with
their more or less woody stems creeping on or beneath the surface
of the ground, yet in" warm climates some species rise with woody
trunks into tall and palm-like trees. But even these, like the hum-

FIG. 98. An individual of a Moss (Physcomitrium pyriformc), enlarged to about twelve
times the natural size 90 'lip of a leal, cut across, mueli niaguiGcd, to show that it is made
up (except the uiidiib) of a sing'.e lajcr of cells.

PLANTS OF TUK HIGHER GRADE,

GO

blest Mosses or the minutest Moulds, spring from single cells or
spores (97), and not from true seeds. And the apparatus by which
these spores are produced, whatever be its nature, is not a flower.
Plants of the lower grade (98,
99) are therefore collectively
denominated

113. Flowerless or Cryptosa-

mOHS PlaillS. The first name
expresses the fact that the or
gans of fructification in these
plants are not of the nature
of real flowers. The second
name, which was introduced
by Linnteus, and is composed
of two Greek words meaning
" concealed fructification," re-
fers to the obscure nature of
the organs or the processes of
reproduction in these plants,
which have only recently come
to be understood. Some ac-
count of them will be given
in Chapter XII

Sect. II. Plants of the Higher Grade ; their Develop-
ment froji the Seed.

114. Flowering Of PliaMlOgamous Plants,* — eo called in contradis-
tinction to the Flowerless or Cryptogamous, — is the general name
for the higher grade of plants, to which our ordinary herbs, shrubs,
and trees belong, and which may be said to exhibit the perfected type
of vegetation. The lower grade begins with plants so simple as to

* Sometimes written Phanerogamous. Both terms are made from the same
Greek words, and signify, by a metaphorical expression, the counterpart of
Cryptogamous ; that is, that the essential organs of the Mower are manifest or
conspicuous.

FIG. 100. Sketch of a Tree Fern, Dicksonia arborescens, of St. Helena ; after Dr J. D.
Hooker. 101. Poh podium vulgaro, a common Fern, with its creeping stem or rootstock.

TO

DEVELOPMENT OF FLOWERING OR PILENOGAMOUS

be destitute of organs ; and it is only in the higher Cryptogamous
plants, such as Mosses and Ferns, that the familiar organs of ordi-
nary vegetation appear as separate parts of the plant, viz. the root,
stem, and leaves. In the higher grade (i. e. in Phamogamous
Plants) these three parts are well defined, and always present, in
some form or other; — a few anomalous instances excepted, such
as the common Duck-weed, for example (Fig. 102).
Here stem and leaf are as it were blended, in the
manner of a Liverwort, to form a flat green body,
which floats on the water, exposing the upper sur-
face like a leaf to the light, while one or more roots
proceed from the lower, and a small and simple
flower at length makes its appearance on some part
of the margin. This is an extremely simplified
state of a Phasnogamous plant.

115. Ordinarily, not only are the root, stem, and
foliage distinct and separate from each other, but
also distinct from the apparatus for reproduction.
So that the plant is composed of two kinds of or-
102 gans, viz. Organs of Vegetation and Organs

of Reproduction.

116. The Organs of Vegetation are the Root, Stem, and Leaves (110).
These are so called because they are jointly concerned in the nutri-
tion and growth of the plant, and in the performance of all its char^
acteristic functions, and they are all that is so concerned. Making
up as they do the entire vegetable, and repeated under varied forms
throughout its whole development, they are also termed the Funda-
mental Organs of plants.

117. The Organs of Reproduction in the simplest Cryptogamous

plants are not distinct from those of vegetation ; but in most plants,
even of the lowest families, the cells for reproduction are different
in appearance and in the mode of their formation from those which
serve for vegetation. These reproductive cells, or Spores, with the
apparatus for their production and protection, whatever it may be,
constitute the organs of reproduction in Cryptogamous plants. In
Phaenogamous plants the organs of reproduction are the Flower,
essentially consisting of Stamens and Pistils, and the result of their
co-operation is the production of Seed.

118. A Seed is a body produced by the agency of a flower, which
contain.?, within one or more coats or coverings, a ready-formed

PLANTS FROM THE SEED. 71

plantlet in a rudimentary state. Flowerless or Cryptogamous plants
spring from spores or single cells, which when ('hey germinate multi-
ply to produce a tissue or an aggregation of cells, that at length
grows and forms a plantlet. But a seed contains a plantlet ready
formed, or a germ, which is called an Embryo. And the history of
a Flowering or Phamogamous plant naturally begins with

119. The Development of the Embryo from the Seed. The embryo

varies exceedingly in size, shape, and appearance in different plants ;
but it is constructed upon the same general plan in all ; and the
development of almost any plantlet from the seed will serve to illus-
trate the principal laws and processes of vegetable growth. To
commence with the study of the seedling is the readiest way to un-
derstand the whole vegetable structure and life.

120. The seeds of the Red or the Sugar Maple furnish good
illustrations, and they are readily met with in germination, i. e. just
developing the embryo into a plant. Also they are large enough to
allow the embryo to be extracted from the seed-coats, and inspected
by the naked eye, or by the aid of a common hand-glass. (Fig.
103-105.) Here

the whole contents — ^ //-t^

of the seed consist //T\\ ff'f^KxS /r\\^^b

of an embryo, neatly \((f$/ SiVn \\ \*^—

coiled up within the ^=^ * .V~™ || ^^

seed-coats.' If un-
folded, or, which is

better, if examined when just unfolding itself in germination, it is
seen to consist of a tiny stem or axis (Fig. 104, 105, a), bear-
ing a pair of small leaves on its summit. The axis is called the
Radicle, because it was supposed to be the root ; though it is really
the rudiment of the stem rather than of the root, and therefore were
better named the Caulicle ; but the former name is now too well
established to be superseded. The two little seed-leaves (b, b) are
technically called Cotyledons : and a little bud which will pres-
ently appear between them (Fig. 106, c), or may be discerned there
in many embryos before germination (as in the Almond, Fig.
108, a) is named the Plumule. The embryo, accordingly, is a
short axis or stem bearing upon one end some rudimentary leaves ;

FIG. 1C3. Embryo of Sugar-Maple as coiled up in the reed. 104. 105. The Fame, just be-
ginning to unfold and develop in germination : a, tiie radicle, or primary stem : b, b, th«
cotyledons or seed-leaves.

DEVELOPMENT OF FLOWERING OR PHLFNOG AMOU3

or, in other words, it is a primary stem crowned with a leaf-bud.
When it grows, this stem elongates throughout its whole length, so
as usually to raise the budding apex ahove the surface of the soil,
into the light and air, where its cotyledons expand into leaves ; and
at the same time from the opposite ex-
tremity is formed the root, which grows
in a downward direction, so as to pen-
etrate more and more into the soil. The
two extremities of the embryo are dif-
ferently organized, are differently affect-
ed by light and air, and grow in opposite
directions. The budding end invaria-
bly turns towards the light, and grows
upwards into the air; the root-end turns
constantly from the light, and buries it-
self in the dark and moist soil. These
tendencies are absolute and irreversible.
If the budding end happen to lie point-
ing downwards and the root end up-
103 wards, both will curve quite round as

they grow to assume their appropriate positions. If obstacles inter-
vene, the root will take as nearly a downward, and the stem as
nearly an upward direction, as possible. These are only the first
manifestations of an inherent property, which continues,* with only
incidental modifications, throughout the whole growth of the plant,
although, like instinct in the higher animals, it is strongest at the
commencement : and it insures that each part of the plant shall be
developed in the medium in which it is designed to live and act, —
the root in the earth, and the stem and leaves in the air. The
plantlet, therefore, possesses a kind of polarit}r ; it is composed of
two counterpart systems, namely, a Descending Axis, or root, and an
Ascending Axis, or stem. The point of union or base of the two
has been termed the crown, neck, or collar. Both the root and stem
branch; but the branches are repetitions of the axis from which
they spring, and obey its laws ; the branches of the root tending
to descend, and those of the stem to ascend.

FIG. 10G A germinating cmhryo of Sugar-Maple, more advanced: a, the radicle elongated
into the first joint of stem, bearing the unfolded cotyledons or seed-leaves, i, and between
them the plumule (c), or rudiments oi the next p^ir oi leaves ; while troiu its lower extremity
the root, cl, is formed.

PLANTS FROM THE SEED.

73

121. The root and the stem grow not only in opposite directions,
hut in a different mode. The little stem, pre-existing in the seed,
grows throughout its whole length, (but most in its upper part,)
so that a radicle of perhaps less than a line in length may become a
stemlet two or three inches long. It is by this elongation that the
seed-leaves are raised out of the soil, so as to expand in the light
and air. Meanwhile a root begins to be formed at the other end of
the radicle; and this lengthens by continued cell-multiplication mainly
at its lower extremity, the parts once formed scarcely if at all elon-
gating afterwards ; but the growth takes place continuously at the tip
alone. The primary stem, bearing the pair of seed-leaves, soon
completes its development, and ceases to lengthen. Then, if not
before, the plumule (Fig. 106, c) begins its growth and develops
into a second stemlet on the summit of

the first, bearing its pair of leaves. It
lengthens in the manner its predeces-
sor did, and carries up the second pair
of leaves to some distance above the
first ; then from between them springs
a third joint of stem, crowned with its
pair of leaves (Fig. 107) ; and so on,
building up the whole herb or tree by
this succession of similar growths or
joints of stem. The root, on the other
hand, grows on in a downward direc-
tion continuously, is not composed of a
series of joints, and bears no leaves or
other organs.

122. The youngest seedling is there-
fore provided with all the organs of
vegetation that the full-grown plant
possesses ; and even the embryo in
the seed is already a miniature vege-
table. It has a stem, from the lower
end of which it strikes root in ger-
mination ; it has leaves, and it has or

soon forms a bud, which develops into new joints of stem bearing
additional leaves, while beneath it sends its root deeper and deeper

FIG. 107. A seedling Maple which has developed two additional joints of stem, each with
their pair of leaves.

7

74

DEVELOPMENT OF FLOWERING OR PHJENOGAMOUS

into the soil. The root absorbs materials for the plant's nourish-
ment from the soil ; these are conveyed through the stem into the
leaves, and there assimilated (12, 15), under the influence of the
light of the sun and the air, into organic matters which serve directly
for further growth, and form the fabric of new portions of stem, new
leaves, and new roots, the vegetable thus increasing its size and its
power at every step.

123. Once established, therefore, the plant can provide for itself,
drawing the needful materials from the earth and the air, and
assimilating or organizing them by its own
peculiar power. But at the beginning, and
until it has sent forth its root into the soil
and spread out its first leaves in the light,
it must be nourished and grow by means of
organized matter supplied by the parent
plant. This supply in the Maple was de-

10S 109 110 111 111"

posited in the seed-leaves of the embryo, and was barely sufficient
to develop the radicle into a tiny stem, to form a simple root at
the lower extremity, and above to expand in the light the pair
of small, green seed-leaves ; when the plantlet is left to its own
resources. Very commonly a larger store of nourishment is pro-
vided for the plant's earliest growth. In the almond, for instance
(Fig. 108), the large cotyledons are so thickened by this nourishing
matter, deposited in their tissue, that they have not the appearance
of leaves. It is the same in the Plum and Cherry (Fig. Ill"),
and in the Apple, only on a smaller scale (Fig. 110, 111) ; and the
Beech (Fig. 112 - 114) and the Bean (Fig. 115 - 117) afford familiar

FIG. 108. Embryo (kernel) of the Almond. 109 Same, with one cotyledon removed, to
show the plumule, a.

FIG 110 Section of an Apple-seed, magnified, cutting through the thickness of the
cotyledons. 111. Embryo of the same, extracted entire, the cotyledons a little separated.

FIG. 111". Germination of the Cherry, showing the thick cotyledons little altered, and
the plumule developing the earliest real foliage.

PLANTS FROM THE SEED.

75

illustrations of the kind. The ample store of nourishment in such
cases enables the germinating plantlet to grow with remarkable
vigor, and to develop the strong plumule
with its leaves before the seed-leaves
have expanded, or the root has obtained
much foothold in the soil. In these
instances the cotyledons are so much
thickened that,
although they
turn greenish
in the light,
they only im-
perfectly as-
sume the ap-
pearance and
perform the(
functions of or-
dinary leaves ;
and the earli-
est real foliage
consists of the
leaves of the
plumule. Such
cotyledon:
serve chiefly
as depositories
of nourishment
for the germi-
nating plant. 1U
124. Still more strongly marked cases of this kind are presented
by the Pea (Fig. 118, 119), the Chestnut and Horsechestnut, the
Oak (Fig. 120, 121), &c. Here the cotyledons are excessively
thickened, so as to lose all likeness to leaves and all power of ful-
filling the office of foliage. Accordingly they remain unchanged
within the seed-coats, supplying abundant nourishment to the

if

FIG. 112 A Beech-nut, cut across. 113 Beginning germination of the Beech, showing
the plumule growing before the cotyledons have opened or the root has scarcely formed.
114. The same, a little later, with the second joint lengthened.

FIG. 115 The embryo (the whole kernel) of the Bean. 116. Same early in germination ;
the thick cotyledons expanding and showing the plumule. 117 Same, more advanced in
germination ; the plumule developed into a joint of stem bearing a pair of leaves.

76

DEVELOPMENT OF FLOWERING OR PHyENOGAMOUS

plumule, which gives rise to the first leaves that appear. As the
radicle itself scarcely if at all elongates, the cotyledons are not ele-
vated in germination but remain under ground (i. e. are hypoyccous),
or rest on the surface of the soil.

125. In all the foregoing illustrations the
nourishment provided for the growth of the
embryo into a plantlet is deposited in the
tissue of the embryo itself, i. e. in the seed-
leaves. In other

cases it is depos-
ited around the

embryo ; when it

forms what is

commonly called

the Albumen of

the seed. This

makes up the

principal bulk of/!

the seed in the

Buckwheat, In-
dian Corn (Fig.

126, 127), and

most other sorts

of grain. The

greater the quan-
tity of this, the

floury part of the

seed, the smaller

or less developed

is the embiyo,

or the less thick

are its cotyledons.

In the Morning- m

Glory, for instance (Fig. 122-125), where the embryo is surround-
ed by mucilaginous albumen, the cotyledons appear in the seed as
a pair of very thin and well-formed green leaves. These absorb
the nourishment required for the plantlet's earliest growth from

FIG. 118. Embryo of a Pea. 119. The same in germination

FIG. 120. An acorn, divided lengthwise, showing a section of the very thick ani fleshy
cotyledons and the very small radicle. 121. Germination of the acorn.

PLANTS FROM THE SEED.

77

the surrounding albumen, which in germination is gradually lique-
fied, its starch or amyloid being transformed into dextrine and
sugar (80, 82, 83). Thus nourished, the radicle rapidly lengthens
into a stem, and develops a root from its 122 123

lower extremity, connecting it with the

soil ; and when the enlarging cotyledons
extricate themselves from the decaying
seed-coats and expand in
the light as the first pair
of leaves, the plantlet is
already established as a
complete miniature vege-
table, able to nourish it-
self, and make sufficient
provision for its own con-
tinued growth. ,a 123

126. The embryo in seeds provided with albumen
is sometimes very small, as in Fig. 131, or even
much more minute, and with its parts' so rudimentary
that they are hardly or not at all discernible previous
to their gradual development in germination. But
sometimes it is pretty large, and with all its parts
i» obvious in the seed; as in the Morning-Glory
and in Indian Corn (Fig. 122). The latter has a highly organized

FTG. 122 Seed and embryo of the common Morning-Glory, cut across ; the latter seen
edgewise. 123 Embryo of the same, detached and straightened, seen flatwise. 124. Germi-
nating Morning-Glory. 125. The same further advanced ; its two thin seed-leaves expanded.

FIG. 126. A grain of Indian Corn, seen flatwise, divided through the embryo, which is
viewed ljing on the albumen, which makes the principal bulk of the seed

FIG 127. Another grain of Corn, cut through the middle in the opposite direction, divid-
ing the embryo through its thick cotyledon and its plumule, the latter consisting of two
leaves, one enclosing the other

FIG 128. The embryo taken out whole : the thick mass is the cotvledon ; the narrow
body partly enclosed by it is the plumule ; the little projection at its base is the very short
radicle enclosed in the sheathing base of the first leaf of the plumule.

FIG. 129. A grain of Indian Corn in germination.

78

DEVELOPMENT OF PH^ENOGAMOUS PLANTS.

embryo, with a strong and well-developed plumule, of several leaves
enwrapped one within another ; and, being amply nourished by the
copious mealy albumen, it sprouts with re-
markable vigor, sending up three or four
leaves in rapid succession before the earliest
has completed its growth, at the same time
sending forth additional roots downwards into
the soil. Here also, as in the Pea and the
Oak, &c. (124) the germination is hypogceous,
the cotyledons remaining in the seed under
ground, and the leaves which
appear above ground belonging
to the plumule. This is also the,'
case in the Iris (Fig. 132) and
most plants of the same class.
But in the Onion the co-
tyledon (which is single)
lengthens, raises the seed
out of the ground, and be-
comes the first leaf.

127. In Indian Corn (Fig.
130), in Iris (Fig. 132), and
also in the germinating Cher-
ry (Fig. Ill"), Oak (Fig.
119), the leaves of the plumule
succeed one another singly, that is, there is only one
upon each joint of stem : in other words, the leaves are
alternate. Whereas in the seedling Beech and the Bean
(Fig. 114, 117) these early leaves are in pairs, that is,
are opposite. A similar difference is to be noticed in the
embryo as to the

128. Number Of Cotyledons. All the earlier illustra-
tions are taken from plants which have a pair of cotyle-
dons, or seed-leaves, belonging to the first joint of stem,
that is, to the radicle. Such embryos are accordingly
said to be Dicotyledonous, — a name expressive of this fact.
But in the Lily, Onion, Iris, Indian Corn, and the like, the embryo

FIG. 130. Indian Corn more advanced in germination, and with a cluster of roots.
FIG. 131 Section of a seed of Iris or Flower-de-Luce, magnified, showing the small emb'-yo
enclosed in the albumen, near its base. 132. Germinating plantlet of Iris.

THE KOOT.

79

has only one cotyledon or true seed-leaf (Fig. 128, &c.) ; the other
leaves, if any are apparent, are enclosed by the cotyledon and be-
long to the plumule ; and the embryo with one cotyledon is ac-
cordingly termed Moxocoxyledonous. The difference in this
respect coincides with striking differences in the
structure of the stems, leaves, and blossoms, and
lays a foundation for the division of Flowering or
Phamogamous plants (114) into two great Classes.

129. In a few plants, such as Pines, the embryo
is provided with from three to ten cotyledons,
which expand into a circle of as many green leaves
in germination (Fig. 133, 134) : such an embryo
is said to be Polycotyledonous, i. e. of many
cotyledons.

130. Having taken this general survey of the \)pf-
development of Phamogamous plants from the
seed, and of their common plan of growth, their
further development and their morphology may 133 134
best be studied by examining in succession the three universal
organs of vegetation (11G) of which they all consist, viz. the Root,
Stem, and Leaves.

CHAPTER III.

OF THE ROOT, OR DESCENDIiNG AXIS.

131. The Root is the descending axis (120), or that portion of
the body of the plant which grows downwards, ordinarily fixing the
vegetable to the soil and absorbing nourishment from it. As already
mentioned (121), the root grows in length by continual additions of
new fabric to its lower extremity, elongating from that part only or
chiefly ; so that the tip of a growing root always consists of the most
newly formed and active tissue. It begins, in germination, at the
root-end of the radicle. That only this extremity of the radicle is
root is evident from the mode in which the radicle grows, namely,

FIG 133 Section of a peed of a Pine, with its embryo of several cotyledons. 134. Early
seedling Piue, with its stemlet, displaying its six seed-leaves.

80

THE ROOT,

by lengthening throughout every part; which is a characteristic
feature of the stem.

132. The root, however, -does not grow from its very apex, as is
commonly stated ; but the new formation (by continued multiplica-
tion of cells, 33) takes place just behind the
apex (Fig. 135), which consists of an obtusely
conical mass of older cells. As these wear
away or perish, they are replaced by the layer
beneath; and so the advancing point of the
root consists, as inspection plainly shows, of
older and denser tissue than the portion just
behind it. The point of every branch of the
root is capped in the same way. It follows
that the so-called spongiolcs or spongelets of

the. roots, or enlarged tips of delicate forming tissue, have no ex-
istence. Not only are there no special organs of this sort, but
absorption evidently does not take place, to any considerable extent,
through the rather firm tissue of the very point itself.

133. Absorption by Roots. As the surface of the root, like every
part of a plant, consists of closed cells, it is evident that the moist-
ure it so largely takes in must iss

be imbibed through the walls of
the cells, by endosmose (40) ;
and that the whole surface of a
fresh root Avill take part in ab-
sorption. The newer the root,
however, the more actively does
it absorb, the cells then having
thinner walls. As they become
older, the superficial layer of
cells thicken their walls and
form a kind of skin, or epider-
mis (69), through which absorp-
tion does not take place so free- 13?
ly. Roots accordingly absorb mostly by their fresh tips and the
adjacent parts ; and these are constantly renewed by growth, and

FIG 135 The tip of the root of a seedling Maple (Fig 106), magnified : n, the place where
growth is mainly taking place, by cell-multiplication : b, the original tip of the radicle

FIG 136, 137 Portions of the surface of the same, highly magnified, showing the nature
<?•" the root-hairs or fibrils.

ITS STRUCTURE AND GROWTH. 81

extended farther into the soil. The absorbing surface of the new
parts of roots is greatly increased by the

134. Root-hairs, or delicate fibrils which they bear. These are
often discernible by the naked eye, as in the young seedling Maple
(Fig. 106), and may almost always be plainly shown by a moderate
magnifying power, as in Fig. 135; while a higher power distinctly
reveals their nature, as prolongations of some of the superficial cells
from a certain point into slender tubes (Fig. 136, 137), thus largely
increasing the absorbing surface. As fast as the superficial cells are
converted into epidermis, the root-hairs die away, fresh ones taking
their place on the newer parts.

135. The advancing extremity of the root consists of parenchyma
alone ; but vessels and woody tissue appear in the forming root
soon after their appearance in the radicle or stemlet above. The
arrangement of the woody matter is generally the same as in the
stem, except that the root seldom exhibits a distinct pUh. The root
increases in diameter in the same manner as the stem. (Chap. IV.
'Sect. IV., V.)

136. The growth of the root and its branches keeps pace with
the development of the stem. As the latter shoots upward and
expands its leaves, from which water is copiously exhaled during
vigorous vegetation, the former grow onward and continually renew
the tender tissue through which the absorption, required to restore
what is lost by evaporation or consumed in growth, is principally
effected. Hence the danger of disturbing the active roots during
the season of growth. In early summer, while new branchlets and
leaves are developing, and when the sap is rapidly consumed by the
fresh foliage, the rootlets are also in rapid action, are extending at a
corresponding rate, and their tender absorbing points are most fre-
quently renewed. They cannot now be removed from the soil with-
out injury, at, the very time when their action is essential to restore
the liquid which is continually exhaled from the leaves. But at the
close of summer, as the leaves become inactive and the growth of
the season is attained, the rootlets also cease to grow, the epidermis
forms a comparatively firm covering quite down to the tip, and ab-
sorption at length ceases. This indicates the proper period for
transplanting, namely, in the autumn after vegetation is suspended,
or in early spring before it recommences.

137. This elongation of roots by their advancing points alone is
admirably adapted to the conditions in which they are placed.

82 THE ROOT,

Growing as they do in a medium of such unequal resistance as the
soil, if roots increased like growing stems, by the elongation of
their whole body, they would be thrown, whenever the elongating
force was insufficient to overcome the resistance, into knotted or con-
torted shapes, ill adapted for the free transmission of fluid. But,
lengthening only at their farthest extremity, they insinuate them-
selves with great facility into the crevices or yielding parts of the
soil, and afterwards by their expansion in diameter enlarge the
cavity ; or, when arrested by insuperable obstacles, their advancing
points follow the surface of the opposing body until they reach a
softer medium. In this manner, too, they readily extend from place
to place, as the nourishment in their immediate vicinity is consumed.
Hence, also, may be derived a simple explanation of the fact, that
roots extend most rapidly and widely in the direction of the most
favorable soil, without supposing any self-determining power beyond
what belong* to all growing parts. (Chap. XIII.)

138. We have taken the root of the seedling as an example and
epitome of that of the whole herb or tree ; as we rightly may, for
in its whole development the root produces no other parts ; it bears
nothing but naked branches, which spring from different portions of
the surface of the main root, nearly as this sprung from the radicle,
and exactly imitate its growth. They and their ramifications are
mere repetitions of the original descending axis, serving to multiply
the amount of absorbing surface. The branches of the root, more-
over, shoot forth irregularly, or at least in no order like that of the
branches of the stem, which have a symmetrical arrangement, de-
pendent upon the arrangement of the leaves (1G6).

139. To the general statement that roots give birth to no other
organs, there is this abnormal, but by no means unusual exception,
that of producing buds, and therefore of sending up leafy branches.
Although not naturally furnished with buds, like the stem, yet,
under certain circumstances, the roots of many trees and shrubs,
and of some herbs, have the power of producing them abundantly.
Thus, when the trunk of a young Apple-tree or Poplar is cut off
near the ground, while the roots are vigorous and full of elaborated
sap, those which spread just beneath the surface produce buds, and
give rise to young shoots. The roots of the Madura, or Osage
Orange, habitually give rise to such irregular or adventitious (168)
buds and branches.

140. Although the root does not produce ascending axes, or stems,

IN ANNUAL AND BIKNNIAL PLANTS. 83

except in certain rather unusual instances, yet stems habitually pro-
duce roots, whenever circumstances favor it, namely, when they are
covered by the damp. and moist soil, or rest on its surface. Roots
accordingly may be distinguished into primary and secondary.

141. The Primary Root is that which originates from the root end
of the embryo in germination, including also its branches. If this
continues as a main root, it commonly forms a tap-root. But very
often the main root, is soon lost in the branches. Sometimes a
cluster of roots is produced directly from the lower extremity of
the radicle, as in the Pumpkin, and Indian Corn (Fig. 130). In the
latter the second and the succeeding short joints of stem also send
out roots. These are early instances of

142. Secondary Roots, i. e. roots emitted by other parts of the
ascending axis than the radicle. Most creeping plants produce
them at every joint ; and" most branches, when bent to the ground
and covered with earth, so as to afford the moisture and darkness
they require, will strike root. So, often, will separate pieces of
young stems, if due care be taken ; as when plants are propagated
by cuttings. Cryptogamous plants, growing from spores and hav-
ing no embryo stem or axis to commence with, are furnished with
secondary roots only.

143. Viewed as to the duration of the plant, roots are distin-
guished into annual, biennial, and perennial.

144. Annual Roots are those of a plant which springs from the
seed, flowers, and dies the same year or season. Such plants
always have fibrous roots, composed of numerous slender branches,
fibres, or rootlets, proceeding laterally from the main or tap-root ;
or else the whole root divides at once into such fibrous branches, as
in all annual Grasses (Fig. 130). These multiplied rootlets are
well adapted for absorption from the soil, but for that alone. The
food which the roots absorb, after being digested and elaborated in
the leaves, is all expended in the production of new leafy branches,
and at length of blossoms. The flowering process and the maturing
of the fruit exhaust the vegetable greatly (in a manner hereafter to
be explained), consuming all the nourishing material which it con-
tains, or storing it up in the fruit or seed for its offspring ; and the
exhausted plant perishes at the close of the season, or whenever it
has fully gone to seed.

145. Biennial Roots are those of plants which do not blossom until
the second season, and which die when they have matured their

84

THE EOOT.

seed. Such plants send up no lengthened stem during the first
summer, but produce a large tuft of leaves next the ground, and .
proceed to elaborate -what they re-
ceive from the roots and from the air
into organic or nourishing matter, and
store it up in the root, in the form of
p^TV, '"^^T/^i^sv starch, vegetable jelly, and the like.
^^^tdl s!\\^ s!h 'jH^^ The root enlarges, or becomes fleshy,
as this accumulates. In biennials this
accumulation generally takes place in
the primary or main root, as in the
Radish, Carrot, Beet, &c. This, when
only moderately thickened and taper-
ing downwards, is a common tap-root :
when more enlarged and broadest at
the crown, or junction with the ex-
tremely abbreviated stem, it forms a
conical root, like that of the common
Beet and Parsnip : when broadest in
the middle and tapering to both ends, it is spindle-shaped or fusi-
form, as in the Radish (Fig. 138) : when much broader than long,
and abruptly contracted below, like a turnip, it is napiform. Such
roots, abounding in nourishment, are appropriated by man for food.
The plant itself uses this store for the same purpose. When the
vegetation of these biennials is resumed, the following spring, the
new shoots, fed by this abundant stock of nourishment provided for
them, grow with great vigor, and produce flowers, fruit, and seed
almost entirely at its expense ; and this stock being exhausted by the
time the seeds are matured, when the cells of the great root will be
found to be emptied of their contents and dead, the plant perishes.

146. Perennial Roots are those of plants which last year after year.
In shrubs and trees the roots themselves live and grow indefinitely ;
but in perennial herbs the same roots seldom survive more than a
year or two, and a new set is formed annually. Here, also, a store
of nourishment for the vigorous commencement of the succeeding
year's growth is not unfrequently deposited in the root. The Sweet
Potato, the Peony, and the Dahlia (Fig. 139), furnish good illustra-
tions of the kind. These roots are generally fascicled or clustered;
that is, they consist of a cluster of roots from the base of the stem.

FIG , 138 Fusiform root of the Radish, with some foliage.

ITS STRUCTURE AND GROWTH.

8;,

While some of these remain slender and serve merely for absorption,

others, thickened by this deposit; may become tuberous (as in Fig.

139) ; and buds, formed on the stem

just above, draw upon this store when

they start into growth in the spring.

These particular roots perish when

exhausted of their store ; but new

accumulations have meanwhile been

formed in some of the roots of the

season, which serve the same purpose

the following spring ; and so the plant

survives, year after year.

147. Some less ordinary modifica-
tions of roots remain to be noticed.
It has already been stated that they
may spring (as secondary roots, 142)
from any part of the stem, although
they commonly do so only when this 139

rests on or is covered by the soil, which affords the darkness and
moisture congenial to them. Some stems, however, strike root freely
in the open air, forming

148. Aerial Roots. The Ivy of Europe, our own Poison Ivy (Rhus
Toxicodendron), and the Trumpet Creeper climb by such roots, in
the form of small rootlets, which attach themselves to the bark of
trees, &c. These serve merely for mechanical support. Other
plants produce larger aerial roots, which, emitted from the stem in
the open air, descend to the ground and establish themselves in the
soil. This may be observed, on a small scale, in the stems of In-
dian Corn, where the lower joints often produce roots which grow
to the length of several inches before they reach the ground. More
remarkable cases of the kind abound in those tropical regions where
the sultry air, saturated with moisture for a large part of the year,
favors the utmost luxuriance of vegetation. The Pandanus or
Screw-Pine (a Palm-like tree, often cultivated in our conserva-
tories) affords a well-known instance. Here (Fig. 140) strong roots,
emitted in the open air from the lower part of the trunk, and soon
reaching the soil, give the tree the appearance of having been par-
tially raised out of the ground. The famous Banyan-tree of India
(Fig. 142) affords a still more striking illustration. In this the

Fascicled tuberous roots of the Dahlia.

8

86

THE ROOT.

aerial rootlets strike from the horizontal branches of the tree, often
at a great height, at first swinging free in the air, but finally reach-
ing and establishing
themselves in the
ground, where they
increase in diame-
ter and form acces-
sory trunks, sur-
rounding the origi-
nal boll and sup-
porting the wide-
spread canopy of
branches and foli-
age. Very similar
is the economy of
the Mangrove (Fig.
141), which forms
impenetrable thick-
ets on low and mud-
dy sea-shores in the
tropics, and even
occurs on the coast
of Florida and Lou-
isiana. Here aerial roots spring not only from the main trunk, as
in the Pandanus, but also from the branchlets, as in the Banyan.

FIG 140. The Pandanus, or Screw-Fine; with, 141. a Mangrove-tree (Rhizophora Mangle)
FIG. 142. The Banyan-tree, or Indian Fig (Fi.us Iudieu).

EPIPHYTES OR AIR-ri.ANT9.

87

Moreovei*, this tendency to shoot in the air is shown even in the
embryo, which begins to germinate while the fruit is yet attached to
the parent branch, often elongating its radicle to the length of a loot
or more before the fruit falls to the ground.

149. Epiphytes, j)r Air-PlaiJtS, exhibit a further peculiarity. Their
roots not only strike in the open air, but throughout their life have
no connection with the soil. These generally grow upon the trunks
and branches of trees ; their roots merely adhering to the bark to
fix the plant in its position, or else hanging loose in the air, from
which such plants draw all their nourishment. Of this kind are a
large portion of the gorgeous Orchidaceous plants of very warm and
humid climes, Avhich are so much prized in hot-houses, and which,
in their flowers as well as their general aspect, exhibit such fantastic
and infinitely varied forms. Some of the flowers resemble butter-

flies, or strange insects, in shape as well as in gaudy coloring ;
such, for example, as the Oncidium Papilio (Fig. 143). To another

FTG 143. Oncidium Papilio, and. 144, Comparettia rosea; two epiphjtes of the OrchU
fjjiiilj ; showing the uiodo in which these Air-plauU grow.

88

THE ROOT.

family of Epiphytic plants belongs the Tillandsia, or Long Moss,
which, pendent in long and gray tangled clusters or festoons from
the branches of the Live-Oak or Long-leaved Pine, gives such a
peculiar and sombre aspect to the forests of the warmer portions
of our Southern States. They are called Air-pl%nts, in allusion to
the source of their nourishment ; and Epiphytes, from their grow-
ing upon other plants, and in contradistinction to

150. Parasites, that not only grow upon other vegetables, but live
at their expense ; which Epiphytes do not. Parasitic plants may
be divided into two sorts, viz.: — 1st, those that have green foliage;
and 2d, those that are destitute of green foliage. They may vary
also in the degree of parasitism ; some being absolutely dependent
upon the foster plant for nourishment, while others, such as the
Cursed Fig (Clusia rosea) of Tropical America, often take root in
the soil, and thence derive a part of their support. The latter oc
curs only in

151. Green Parasites, or those furnished with green foliage, or
proper digestive organs of their own. These strike their roots

through the bark and directly into the new wood of the foster
plant ; whence they draw the ascending, mostly crude sap, which

they have to assimilate in
their own green leaves.
The Mistletoe is the most
familiar example of this
class. It is always com-
pletely parasitic, being at no
period connected with the
earth ; but the seed germinates upon the trunk or branch of the

FIG 145 Roots of Gerardia flava , some of the rootlets attaching themselves parasitically
to the root of a Blueberry. (From a drawing by Mr J StaufTer )

HG. H6 Section of one of the attached rootlets, showing the union.

TARASITIC TLANTS.

80

tree where it happens to fall, and its nascent root, or rather the
woody mass that it produces in place of the root, penetrates the
hark of the foster stem, and forms as close a junction with its young
wood as that of a natural branch. The Cursed Fig, commonly be-
ginning as a parasite, sends down aerial roots, some of which strike
into the wood of the foster tree lower down, while others descend
to the ground and draw from it a portion' of their sustenance in the
ordinary manner. Some common herbaceous plants, hitherto not
suspected of such habits, have recently been found to fix themselves
clandestinely, under ground, by means of some of their rootlets, to
the roots of neighboring plants, and furtively draw from them a
portion of their sustenance. This is the case with our Comandra,
as well as with the Thesiums of the Old World, and also with our
Gerardias and many other plants of that family, which have long
been known as uncuhivable, although the cause of their being so
has only lately been detected. It would appear that this partial
parasitism is necessary to their existence. Gerardia appears to im-
plant its rootlets upon the bark of the roots of neighboring shrubs,
and therefore to steal elaborated sap (Fig. 14o, 14G).

152. Pale or Colored Parasites, such as Beech-Drops, Pine-Sap,
&c, are those which are destitute of
green herbage, and are usually of a
white, tawny, or reddish hue ; in fact,
of any color except green. These
strike their roots, or sucker-shaped
discs, into the bark, mostly that of
the root, of other plants, and thence
draw their food from the sap already
elaborated. They have accordingly
no occasion for digestive organs of
their own, i. e. for green foliage.
The Dodder (Fig. 147) is a common
plant of this kind which is parasitic
above ground. Its seeds germinate
in the earth ; but when the slender
twining stem reaches the surrounding

FIG 147 The common Dodder of the Northern States (Cuscuta Gronovii), of the natural
nizo, parasitic upon the stem of an herb : the uncoiled portion ftt the lower end shows the
mode of its attachment 148. The coiled embryo taken from the seed, moderately magnified.
149 The same in germination ; the lower end elongating into a root, the upper into a thread-
like leafless stem.

8*

90 THE ROOT.

herbage, it forms suckers, which attach themselves firmly to the
surface of the supporting plant, penetrate its epidermis, and feed
upon its juices ; while the original root and base of the stem perish,
and the plant has no longer any connection with the soil. Thus
stealing its nourishment ready prepared, it requires no proper diges-
tive organs of its own, and, consequently, does not produce leaves.
This economy is foreshadowed in the embryo of the Dodder, which
is a naked thread spirally coiled in the seed (Fig. 148, 149), and
presenting no vestige of cotyledons or seed-leaves. A species of Dod-
der infests and greatly injures flax in Europe, and sometimes makes
its appearance in our own flax-fields, having been introduced with
the imported seed. Sach parasites do not live upon all plants in-
discriminately, but only upon those whose elaborate juices furnish a
propitious nourishment. Some of them are restricted, or nearly so,
to a particular species ; others show little preference, or are found
indifferently upon several species of different families. Their seeds,
in some cases, it is said, Avill germinate only when in contact with
the stem or root of the species upon which they are destined to live.
Having no need of herbage, such plants may be reduced to a stalk
bearing a single flower (Fig. 965) or a cluster of flowers (Fig. 968),
or even to a single blossom developed from a bud directly parasitic
on the bark of the foster plant. Of this kind are the several species
of Pilostyles (parasitic flowers on the shoots of Leguminous plants)
in Tropical America, one species of which was recently discovered
by Mr. Thurber near the southern borders of New Mexico. Here
the flowers are small, only about a quarter of an inch in diameter.
The most wonderful plant of this kind is that vegetable Titan, the
RafHesia Arnoldi of Sumatra (Fig. 150), which grows upon the
stem of a kind of Grape-vine. It is a parasitic flower, measuring

TIO 150 Rafflesia Arnoldi ; an expanded flower, and a bud, directly parasitic on the stem
of a vine : reduced to the scale of half an inch to a foot.

THK STEM. 91

nine feet in circumference, and weighing fifteen pounds ! Its color
is light orange, mottled with yellowish-white.

153. Among Cryptogamous plants, numerous Fungi are parasitic
upon living, especially upon languishing vegetables ; others infest
living animals ; the rest feed on dead or decaying vegetable or
animal matters : all are destitute of chlorophyll or anything like
green herbage. It is probable that our Monotropa, or Indian Pipe,
a pallid Phamogamous plant, looking like a Fungus, actually lives
like one, and draws its nourishment, at least in great part, from the
decaying leaves among which it grows.

CHAPTER IV.

OP THE STEM, OR ASCENDING AXIS.
Sect. I. Its General Characteristics and Mode of Growth.

154. The Stem is the ascending axis, or that portion of the trunk
which in the embryo grows in an opposite direction from the root,
seeking the light, and exposing itself as much as possible to the air.
All Phamogamous plants (114) possess stems. In those which are
said to be acaidescent, or stemless, it is either very short, or concealed
beneath the ground. Although the stem always takes an ascending
direction at the commencement of its growth, it does not uniformly
retain it ; but sometimes trails along the surface of the ground, or
burrows beneath it, sending up branches, flower-stalks, or leaves
into the air. The common idea, that all the subterranean portion
of a plant belongs to the root, is by no means correct.

155. The root gives birth to no other organs, but itself directly
performs those functions which pertain to the relations of the vege-
table with the soil; — its branches bind the plant to the earth; its
newly formed extremities or rootlets imbibe nourishment from it.
But the aerial functions of vegetation are chiefly carried on, not so
much by the stem itself as by a distinct set of organs which it bears,
namely, the leaves. Hence, the production of leaves is one of the

92 THE STEM,

characteristics of the stem. These are produced only at certain
definite and symmetrically arranged points, called

15G. Nodes, literally knots, so named because the tissues are here
more or less condensed, interlaced, or interrupted, as is conspicuous-
ly seen in the Bamboo, in a stalk of Indian Corn, or of any other
Grass. Here each node forms a complete ring, because the leaf
arises from the whole circumference of the stem at that place.
When the base of the leaf or leafstalk occupies only a part of the
circumference, the nodes are not so distinctly marked, except by
the leaves they bear, or by the scars left by their fall (Fig. 151, &c.)
They are often called joints, and sometimes, indeed, the stem is
actually jointed, or articulated, at these points ; but commonly there
is no tendency to separate there. Each node bears either a single
leaf (as in Fig. Ill, 121, &c), or two leaves placed on opposite
sides of the stem (as in Fig. 107), or else three or more, placed in
a ring (in botanical language, a whorl or verticil) around the stem.
The naked portions or spaces that intervene between the nodes are
termed

157. Itltcmodes. The undeveloped stem is, in fact, made up of a
certain number of these leaf-bearing points, separated by short in-
tervals ; and its growth consists, primarily, in the successive elonga-
tion of these internodes so as to separate the nodes more or less, and
allow the leaves to expand.

158. This brings to view the leading peculiarity of the stem;
namely, that it is formed of a succession of similar parts, developed
one upon the summit of another, each with its own independent
growth. Each developing internode, moreover, lengthens through-
out its whole body, unlike the root, which elongates continuously
from its extremity alone (121). To have a good idea of this, we
have only to observe the gradual evolution of a germinating plant,
where each internode develops nearly to its full length, and ex-
pands the leaf or pair of leaves it bears, before the elongation of
the succeeding one commences. As already described (120, &c),
the radicle, or internode which pre-exists in the embryo, elongates,
and raises the seed-leaves into the air ; they expand and elaborate
the material for the next joint, the leaves of which in turn prepare
the material for the third, and so on. The internode lengthens
principally by the elongation of its already formed cells, particularly
in its lower part, which continues to grow after the upper portion
has finished.

ITS STRUCTURE AND GROWTH.

93

159. Buds. The apex of the stem, accordingly, is always crowned
with an undeveloped portion, with rudimentary parts similar to
those already unfolded, that is, with a Bud. The embryo itself
may be viewed as an internode (the radicle) bearing the fundamental
bud (the plumule) on its apex, from which the whole plant is de-
veloped; just as an ordinary bud of a tree or shrub develops to
form the growth of the season. Except that, in the latter case, the
different steps follow each other more closely ; for the bud usually
has a considerable number of parts ready formed in miniature before
it begins to grow, and has a full store of assimilated sap accumulated
in the parent stem to feed upon. This is no less the case in many
strong embryos highly developed in the seed, and supplied with
abundant nourishment, either in
the cotyledons, as in the Pea
(Fig. 119) and Oak (Fig. 120),
or in the albumen, as in Indian
Corn (Fig. 126-130). The
strong buds which in many
shrubs and trees crown the
apex of a stem when it has
completed its growth for the
season, often exhibit the whole
plan and amount of the next
year's growth ; the nodes, and
even the leaves they bear, being
already formed, and only re-
quiring the elongation of the
internodes for their full ex-
pansion. This is rudely shown
in the annexed diagrams, Fig.
151, 152. As the bud (Fig. a
153) is well supplied with
nourishment in spring by the
stem on which it rests, its axis elongates rapidly ; and although the
growth commences with the lowest internode, yet the second, third,

FIG. 151. Diagram of the vertical section of a strong bud, such as that of Ilorsechestnut.

FIG. 152. The axis of the same developing, the elongation beginning with the lowest inter-
node, soon followed by the others in succession.

FIG. 153. A year's growth of Horsc.hestnut, crowned with a terminal bud : a, scars left
by the bud-scales of the previous year : b. scars left by the fallen leafstalks : c , axillary buds.

FIG 154. Branch and buds (all axillary) of the lilac.

94

THE STEM,

and fourth internodes, &c. have begun to lengthen long before the
first has attained its full growth. The stem thus continued from
a terminal bud is, if it survive, again terminated with a similar bud
155 iss at the close of the season, which in its

development repeats the same process.
A set of narrow rings on the bark
(Fig. 153, a) commonly mark the limit
of each year's growth. These are the
scars left by the fall of the scales of
the bud ; and these, in the Horsechest-
nut, and other trees Avith large scaly
buds, may be traced back on the stem
for a series of years, growing fainter
with age, until they are at length ob-
literated by the action of the weather
and the distention caused by the in-
crease of the stem in diameter. The
same is the case with the more con-
spicuous leaf-scars, or marks on the
bark left by the separation of the leaf-
stalk, which are for a long time con-
spicuous on the shoots of the Horse-
chestnut (Fig. 153, b) and the Mag-
nolia (Fig. 155).

160. A bud, therefore, is nothing
more than the first stage in the de-
velopment of a stem, with the axis still
so short that the rudimentary leaves
within successively cover each other,
while the whole is covered and pro-
tected by the scales without. Buds
vary greatly, however, in size, ap-
pearance, and degree of development.
Those of many shrubs and trees are
minute, and hidden by the bark until
their vernal growth commences, as in

FIG. 155. Branch of Magrolia Umbrella, of the natural size, crowned with the terminal
bud ; and below exhibiting the large, rounded leaf-scars, as well as the rings or annular scars
left by the fall of the bud-scales of the previous season 15G A detached scale from a similar
bud ; its thickened axis is the base of a leafstalk ; the membranous sides consist of the pair of
stipules.

ITS STRUCTURE AND GROWTH. 95

Sumac, Locust, Honey-Locust (Fig. 1G4), &c. : in these buds the
parts are few and very rudimentary, and are mostly formed
as they develop. In some, they are naked, that is, are entirely
destitute of protecting scales, and exhibit the forming leaves directly
exposed to the air, just as they are in herbs. This occurs in many
tropical trees, but not in all, and in some shrubs of cold climates,
such as our Viburnum nudum and V. lantanoides. But the greater
number of plants which have a winter to endure are provided with
scaly buds. Those of Beech and Hickory, as well as of Horsechest-
nut and Magnolia already referred to, are conspicuous and well-
developed examples. The scales serve to protect the tender parts
within against injury from moisture and from sudden changes in
temperature during the dormant state. To ward off moisture more
'effectually, they are sometimes coated with a waxy, resinous, or
balsamic exudation, as is conspicuous on the scales of the Horse-
chestnut, Balsam-Poplar or Balm of Gilead, and Balsam-Fir. To
guard against sudden changes of temperature, they are often lined,
or the rudimentary leaves within invested with non-conducting
down or wool.

161. The bud-scales themselves are leaves in a modified state.
This is evident from their situation and arrangement, which are
the same as of the proper leaves of the species, and by the gradual
transitions from the former to the latter in many plants. In the
turions, or subterranean budding shoots of numerous perennial
herbs, and in the unfolding buds of the Lilac and Sweet Buckeye
(JEsculus parviflora), every gradation may be traced between bud-
scales and foliage, showing that no absolute line can be drawn be-
tween them, but that the two are essentially of the same nature, i. e.
are different modifications of the same organ.

162. Plail of Vegetation. In fact, a simple stem bears nothing but
leaves in some form or other, and its branches are only repetitions
of itself, following the same laws. The embryo consists of a pri-
mary joint of stem crowned with a bud, the first leaves or leaf of
which takes the special form of cotyledons ; the following ones de-
velop as ordinary foliage, and leaf after leaf, or pair after pair, is
formed and elevated upon the successive internodes as the stem is
built up. At the close of the growing season, if the stem is to
endure, this is terminated, as it began, by a bud ; and the bud-scales,
if any, are leaves developed in this peculiar form, subservient to
protection alone, and borne upon nodes which are never separated

THE STEM.

by elongation of the internodes. With the ensuing spring growth
recommences, and another set of internodes, and of nodes bearing
ordinary leaves, form the second year's growth, like the first ; and
so, by annual increments, a simple leafy stem is developed and
carried up. Not only is the whole stem growing from year to year
thus composed of a succession of similar growths, each the offspring
of the preceding and the parent of the next,
but also each annual growth itself consists of a
lineal succession of similar parts, viz. of leaf-
bearing joints of stem, developed each upon its
predecessor, and in turn surmounted by the
next in the series. These similar parts, which
by their repetition make up the Phamogamous
plant, have been termed

163. PhytOllS (from the Greek ^utoV, plant),
or plant-elements. The first phyton is the
radicle of the embryo, with its^W/ftyledon or
pair of cotyledons, from its btis^tfev eloping the
root, from above expanding its leaf or pair of
leaves (as already described in detail, 119 —
122), and then giving birth to the next phyton,
or joint of stem and leaf, and so on, in lineal
succession. So that the whole herb, shrub, or
tree, as to its upward growth, is a multiplica-
tion of the simple plantlet it began with as it
developed from the seed. Moreover, any joint
of stem, when favorably situated for the pur-
pose, may produce secondary roots (142), and
thus complete the vegetable individuality, hav-
ing all the organs of vegetation (116).

164. The repetition of these similar parts in
137 the direct line, each from the summit of its pre-
decessor, builds up a simple or main stem, to which many plants are
restricted during the first year's growth, and some, such as Palms
and Reeds, throughout their whole existence. Their production
from new starting-points gives rise to branches.

FIG 157. Diagram of a pimple-stemmed plant, like
phytons, a to g, of which it is composed.

Grass, and of the similar parts, or

RAMIFICATION. 97

Sect. H. Ramification.

1G5. Branches spring fsoni lateral or axillary buds. These are
new growing points, which habitually appear, or at least may ap-
pear, one (or occasionally two or three) in the axil of each leaf, —
that is, in the upper angle which the leaf forms with the stem. (See
Fig. 1 53, c, where the point at which the fallen leaves were attached
is marked by the broad scar, b, just below the bud.) When these
buds grow, they give rise to Branches ; which are repetitions, as it
were, of the main stem, growing just as that did from the seed ; ex-
cepting merely, that, while that was implanted in the ground, these
proceed from the parent stem. The branches are in turn provided
with similar buds in the axils of their leaves, capable of developing
into branches of a third order, and so on indefinitely, producing the
whole ramification of the plant. The ultimate ramifications are
termed Branchlets.

16G. The arrangement of axillary buds depends upon that of the
leaves. When the leaves are opposite (that is, two on each node,
placed on opposite sides of the stem), the buds in their axils are
consequently opposite; as in the Maple, Horsechestnut (Fig. 153),
Lilac (Fig. 154), &c. When the leaves are alternate, or one upon
each node, as in the Apple, Poplar, Oak, Magnolia (Fig. 155), &c,
the buds implicitly follow the same arrangement. Branches, there-
fore, being developed axillary buds, their arrangement follows that
of the leaves. When the leaves are alternate, the branches will be
alternate ; when the leaves are opposite, and the buds develop regu-
larly, the branches will be opposite. But the perfect symmetry of
the ramification, thus provided for, is frequently obscured by the

1G7. Non-development of some of Hie Buds. As the original bud of

the embryo remains for a time latent in the seed, growing only
when a conjunction of favorable circumstances calls its life into
action, so also many of the buds of a shrub or tree may remain
latent for a long time, and many of them fail to grow at all. In our
trees, most of the lateral buds generally remain dormant for the first-
season : they appear in the axils of the leaves early in summer, but
do not grow into branches until the following spring ; and even then
only a part of them usually grow. Sometimes the failure occurs
without appreciable order; but it often follows a nearly uniform
rule in each species. Thus, when the leaves are opposite, there aro
9

98 THE STEM.

usually three buds at the apex of a branch ; namely, the terminal,
and one in the axil of each leaf; but it seldom happens that all
three develop at the same time. Sometimes the terminal bud con-
tinues the hranch, the two lateral generally remaining latent, as hi
the Horscchestnut (Fig. 153) ; sometimes the terminal one regu-
larly fails, and the lateral ones grow, when the stem annually be-
comes two-forked, as in the Lilac (Fig. 154). The undeveloped
buds do not necessarily perish, but are ready to be called into action
in case the others are checked. When the terminal buds are
destroyed, some of the lateral, that would else remain dormant,
develop in their stead, incited by the abundance of nourishment,
which the former would have monopolized. In this manner our
trees are soon reclothed with verdure, after their tender foliage and
branches have been killed by a late vernal frost, or other injury.
And buds which have remained latent for several years occasionally
shoot forth into branches from the sides of old stems. Such branch-
es, however, more commonly originate from irregular, accidental, or,
as they are named

168. Adventitious Buds. It has been already remarked, that roots,
although naturally destitute of buds, do yet produce them in certain
plants, especially when wounded (139). So likewise do the stems
of some shrubs and trees, especially when surcharged with sap, as
is commonly seen in Willows and Lombardy Poplars. Here buds
break out habitually on the sides of trunks, at least when they are
wounded or pollarded, or spring from the cut surface where the bark
and avooc! join. These adventitious buds do not originate from
nodes, nor affect any order in their appearance, but are wholly
casual as to the point of origin. Thus the predestined symmetry of
the branches is obscured or interfered with in two distinct ways ;
first, by the failure of a part of the regular buds to develop ; and
secondly, by the irregular and casual development of buds from
other parts than the axils of the leaves : to which Ave may add, that
great numbers of branches perish and fall away after they have be-
gun to gi-ow. There is still another source of irregularity, namely,
the production of

1G9. Accessory Buds. These are, as it Avere, multiplications of the
regular axillary bud, giving rise to two, three, or more buds, instead
of one ; in some cases situated one above another, in others side by
side. In the latter case, Avhich occurs occasionally in the Hawthorn,
:n certain WilloAvs, in the Maples (Fig. 158), &c, the axillary bud

RAMIFICATION.

99

fl

seems to divide into three, or itself give rise to a lateial bud on
each side. On some shoots of the Tartarean Honeysuckle (Fig.
1G0) from three to six buds appear in
each axil, one above another, the lower
being successively the stronger and earlier
produced, and the one immediately in the
axil, therefore, grows in preference : oc-
casionally two or more of them grow, and
superposed accessory branches result. It
is much the same in Aristolochia Sipho,
except that the uppermost bud is there
strongest. So it is in the Butternut (Fig.
159), where the trae axillary bud is mi-
nute and usually remains latent, while the
accessory ones are considerably remote,
and the uppermost, which is much the
strongest, is far out of the axil ; this
usually develops, and gives rise to an
extra-axillary branch.

170. Excurrent ami Deliquescent Stems.

Sometimes the primary axis is prolonged
without .interruption, by the continued
evolution of a terminal bud, even through
the whole life of a tree (unless acciden-
tally destroyed), forming an undivided
main trunk, from which lateral branches proceed ; as in most Fir-
trees. Such a trunk is said to be excurrent. In .other cases the

main stem is arrested, sooner or
later, either by flowering, by the
failure of the terminal bud, or by
the more vigorous detelopment
of some of the lateral buds ; and
thus the trunk is dissolved into
branches, or is deliquescent, as in
160 the White Elm and in most of

our deciduous-leaved trees. The first naturally gives rise to conical

FIG. 158. Branch of Red Maple, with triple axillary buds, placed side by side.

FIG. 159 Piece of a branch of the Butternut, with accessory buds placed ODe above
another : a, the leaf-scar : 4, proper axillary bud c, il, accessory buds.

FJG 160. Part of a branch of Tartarean Honey suckle, with crowded accessory buds in
each axil

100 THE STEM.

or spire-shaped trees ; the second, to rounded or spreading forms.
As stems extend upward and evolve new brunches, those near the
base, being overshadowed, are apt to perish, and thus the trunk be-
comes naked below. This is well seen in the excurrent trunks of
Firs and Pines, which, when grown in forest, seem to have been
branchless for a great height. But the knots in the centre of the
trunk are the bases of branches, which have long since perished,
and have been covered with a great number of annual layers of
wood, forming the clear stuff of the trunk.

171. Definite and Indefinite Annual Growth of Branches. In the

larger number of our trees and shrubs, especially those with scaly
buds, the whole year's growth is either already laid down rudi-
mentally in the bud (159), or else is early formed, and the develop-
ment is completed long before the end of summer ; when the shoot is
crowned with a vigorous terminal bud, as in the Horsechestnut (Fig.
158) and Magnolia (Fig. 155), or with the uppermost axillary buds,
as in the Lilac (Fig. 154) and Elm. Such definite shoots do not
die down at all the following winter, but grow on directly, the next
spring, from these terminal or upper buds, which are generally more
vigorous than those lower down. In other cases, on the contrary,
the branches grow onward indefinitely through the whole summer,
or until arrested by the cold of autumn : they mature no buds at or
near their summit ; or at least the lower and older axillary buds
are more vigorous, and alone develop into branches the next spring ;
the later-formed upper portion most commonly perishing from the
apex downward for a certain length in the winter. The Rose and
Raspberry, and among trees the Sumac and Honey Locust, are
good illustrations of this sort ; and so are most perennial herbs,
their stems dying down to or beneath the surface of the ground,
where the persistent base is charged with vigorous buds, well pro-
tected by the ground, for the next year's vegetation.

172. Propagation from Buds. Buds, being, as it were, new indi-
viduals springing from the original stem, may be removed and
attached to other parts of the parent trunk, or to that of another
individual of the same, or even of a different, but nearly related
species, where they will grow equally well. This is directly accom-
plished in the operation of budding. In ingrafting, the bud is
transferred, along with a portion of the shoot on which it grew.
Moreover, as the cut end of such shoots, when buried in moist and
■warm soil, will commonly, under due care, send out adventitious

KINDS OF STEM AND BRANCHES. 101

roots, they may be marie to grow independently, drawing their
nourishment immediately from the soil, instead of indirectly through
the parent trunk. This is done in the propagation of plants by
cuttings. The great importance of these horticultural operations
depends chiefly on the well-known fact, that buds propagate indi-
vidual peculiarities, which are commonly lost in raising plants from
the seed.

Sect. III. Thk Kinds of Stem and Branches.

173. On the size and duration of the stem the oldest and most
obvious division of plants is founded, namely, into Herbs, Shrubs,
and Trees.

174. Herbs are plants in which the stem does not become woody
and persistent, but dies annually or after flowering, down to the
ground at least. The difference between annual, biennial, and
perennial herbs has already been pointed out (144-146). The
same species is so often either annual or biennial, according to cir-
cumstances or the mode of management, that it is convenient to
have a common name for plants that flower and fruit but once, at
whatever period, and then perish: such De Candolle accordingly
designated as Monocarpic plants; while to perennials, whether
herbaceous or woody, large or small, he applied the counterpart
name of Polycarpic plants, signifying that they bear fruit an
indefinite number of times.

175. Undmhrubs, or suffruticose plants, are woody plants of hum-
ble stature, their stems rising little above the surface. If less
decidedly woody, they are termed suffrutescent.

176. Shrubs are woody plants, with stems branched from or near
the ground, and less than five times the height of a man. Between
shrubs and trees there is every intermediate gradation. A shrub
which approaches a tree in size, or imitates it in aspect, is said to
be arborescent.

177. Trees are woody plants with single trunks, which attain at
least five times the human stature.

178. A Culm is a name applied to the peculiar jointed stem of
Grasses and Sedges, whether herbaceous, as in most Gx-asses, or
woody or arborescent, as in the Bamboo.

179. A Caudex is a name usually applied to a Palm-stem (Fig.

9*

/02 - THE STEM.

184), to that of a Tree Fern (Fig. 100), and to any persistent,
erect or ascending, root-like forms of main stems.

180. Those stems which are too weak to stand upright, but re-
cline on the ground, rising, however, towards the extremity, are
said to be decumbent : if they rise obliquely from near the base,
they are said to be ascending. When they trail flat on the ground,
they are procumbent, prostrate, or running ; and when such stems
strike root from their lower surface, as they are apt to do, they are
said to be creeping, or repent. They are climbing when they cling
to neighboring objects for support; whether by tendrils, as the
Vine and Passion-flower, by their leafstalks, as the Virgin's Bower
(Clematis), or by aerial rootlets, as the Poison Oak (Rhus) ; and
twining, or voluble plants, when they rise, like the Convolvulus, by
coiling spirally around stems or other bodies within their reach.
Other modifications of the stem or branches have received particu-
lar names, some of which merit notice from having undoubtedly sug-
gested several operations by which the cultivator multiplies plants.

181. A Stolon is a branch which naturally curves or falls down to
the ground, where, favored by shade and moisture, it strikes root,
and then forms an ascending stem, capable of drawing its nourish-
ment directly from the soil,- and, by the perishing of the portion
which connects it with the parent stem, at length acquiring an
entirely separate existence. The Currant, Gooseberry, &c., multi-
ply in this way, and doubtless suggested to the gardener the opera^
tion of layering ; in which he not only takes advantage of and
accelerates the attempts of nature, but incites it in species which do
not ordinarily multiply in this manner.

182. A Slicker is a branch of subterranean origin, which, after run-
ning horizontally and emitting roots in its course, at length, follow-
ing its natural tendency, rises out of the ground and forms an erect
stem. The Pose, the Raspberry, and the Mint afford familiar illus-
trations, as well as many other species which shoot up stems "from
the root," as is generally thought, but really from subterranean
branches. Cutting off the connection with the original root, the
gardener propagates such plants by division.

183. A Runner, of which the Strawberry furnishes the most familiar
example, is a prostrate, slender branch, sent off from the base of the
parent stem, which strikes root at its apex, and produces a tuft of
leaves ; thus giving rise to an independent, plant capable of extend.
ing itself in the same manner.

RUNNERS, TENDRILS, ETC.

103

184. An Offset is a similar, but short, prostrate branch, with a tuft
of leaves at the end, which, resting on the ground, there takes root,
and at length becomes independ-
ent; as in the Houseleek.

185. A Tendril is commonly a
thread-like, leafless branch, capable
of coiling spirally, by which' some
climbing plants attach themselves
to surrounding bodies for support ;
as in the Grape-vine (Fig- 1G1).
But sometimes tendrils belong to
the leaves, as in the Pea; when
they are slender prolongations of
the leafstalk. Some tendrils cling
by hooking their tips around the
supporting object. Others, such as
those of the Virginia Creeper (Fig.
1G2, 163), commonly expand the
tips of the tendrils into a flat disc, —
much as do many aerial rootlets (as
those of Ivy) when subservient to
the same office, — which firmly ad- ,61

heres to walls or the bark of trees, thus enabling the plant to ascend
and cover their surface. As soon as they are attached, tho vtj^lril

FIG. 161 End of a shoot of the Grape-vine, with young tendrils

FIG 162. A portion of a stem of Ampelopsis, or Virginia Creeper, with a leaf and a tend iL

FIG. 163 Ends of the latter, enlarged, showing the expanded tips by which they cling.

104

THE STEM.

usually shortens itself by coiling spirally, thus drawing up the
climbing shoot closer to the supporting object.

186. A Spine Of Thorn is an imperfectly developed, indurated, leaf-
less branch of a woody plant, attenuated 10 a point. The nature of

spines is manifest in the Haw-
thorn (Fig. 165), not only by
their position in the axil of a
leaf, but often by producing im-
perfect leaves and buds. And
in the Sloe, Pear, &c, many
of the stinted branches become
spinose or spinescent at the
apex, tapering off gradually in-
to a rigid, leafless point, thus
exhibiting every gradation be-
tween a spine and an ordinary
branch. These spinose branch-
es are less liable to appear on
the cultivated tree, when duly
cared for, such branches being
thrown mostly into more vigor-
ous growth. In the Hawthorn,
the spines spring from the main
axillary bud, while accessory
buds (169), one on each side, ap-
pear, and one or both grow the
next season into an ordinary
branch. In the Honey Locust, it is the uppermost of several ac-
cessory buds, placed far above the axil, that develops into the thorn
(Fig. 164). And here the spine itself branches, and sometimes be-
comes extremely compound. Sometimes the stipules of the leaves
develop into spines, as in the Prickly Ash. Sometimes the leaf it-
self is developed as a spine ; of which 'the Barberry affords a familiar
example. When the spine is situated in the axil of a leaf or a leaf-
scar, it is necessarily of the nature of a branch. When it bears a

Flfl 104. Branching thorn of the Honey Locust (Gleditschia), an indurated branch devel-
oped ftoni an accessory bud produced above the axil. a. Three buds under the base of the
leafstalk, brought to view in a section of the stem and leafstalk below.

FIG. 105 Thorn of the Cockspur Thorn, developed from the central of three axillary buds ;
ene of the lateral buds is seen at its base.

ITS SUBTF.RRANKAN MODIFICATIONS. 105

bud or branch in its axil (as in the Barberry, Fig. 296), it must be
of the nature of a leaf.
187. The Subterranean Modifications of the Stem are scarcely less

numerous and diverse than the aerial ; but they may all be reduced
to a few principal types. They are perfectly distinguishable from
roots by producing regular buds, or by being marked with scars,
which indicate the former insertion of leaves, or furnished with
scales, which are the rudiments or the vestiges of leaves. All the
Scaly roots of the older botanists are therefore forms of the stem or
branches, with which they accord in every essential respect. So,
likewise, what are popularly called Creeping roots are really subter-
ranean branches ; such as those of the Mint, and of most Sedges and
Grasses. Some of these, such as the Carex arenaria (Fig. 1GG) of

Europe, render important service in binding the shifting sands of
the sea-shore. Others, like the Couch-Grass, are often very trouble-
some to the agriculturist, who finds it next to impossible to destroy
them by the ordinary operations of husbandry ; for, being furnished
with buds and roots at every node, which are extremely tenacious of
life, when torn in pieces by the plough, each fragment is only placed
^in the more favorable condition for becoming an independent plant.
The Nut-Grass (Cyperus Hydra), an equally troublesome pest to
the planters of Carolina and Georgia, is similarly constituted ; and

FIG 166 Creeping subterranean stem of Carex arenaria.

FIG. 167. Rhizoma of Diphyllcia cymosa, showing six years' growth, and a bud fcr the
seventh : a, the bud : 4, base of the stalk of the current year : c, scar left by the decay of the
annual stalk of the year before ; and beyond are the scars of previous } oars

106

xh:s stem.

besides, the interminable subterranean branches bear tuber*, or
reservoirs of nutritive matter, in their course, which have still
greater powers of vitality, as they contain a copious store of food
for the development of the buds they bear. The name of

188. Rllizoma or RootstOCk is applied in a general way to all these
perennial, horizontally elongated, more or less subterranean, root-
like forms of
the stem ; and
more particu-
larly to those
that are consid-
erably thick-
ened by the ac-
163 cumulation of

starch or other forms of nutritive matter in their tissue, such as the
so-called roots of Ginger, of the Iris or Flower-de-luce (Fig- 291), of
the Calamus or Sweet Flag, and of the Blood-
root. They grow after the manner of ordinary
stems, advancing from year to year by the
annual development of a bud at the apex, and
emitting roots from the under side of the whole
surface ; thus established, the older portions die
and decay, as corresponding additions are made
to the opposite growing extremity. Each year's
growth is often marked, as in some species of
Iris (Fig. 291), by a narrowing at the place
where the growth of the season is suspended,
followed by an enlargement where it recom-
mences ; or else, as in the curious Diphylleia of
the Alleghany Mountains (Fig. 167), and the Polygonatum or
Solomon's Seal (Fig. 168), it is more indelibly stamped by an im-
pressed circular scar (which has been likened to the impression of a
seal), left annually, in autumn, by the death and separation from the
perennial rootstock of the herbaceous stalk of the season which bore
the foliage and blossoms. In Diphylleia the growth is so slow, and
the ascending stems so thick, that the scars of successive years are

FIG. 168 Rootstock of Polygonatum or Solomon's Seal, with the terminal bud, the base of
the stalk of the season, and three scars from which the latter has separated in as many former
years

FIG. 169 The short and upright rootstock of Trillium erectum, or Cirthroot, with its ter-
minal bud

ROOTSTOCKS AND TUBERS.

107

nearly in contact (Fig. 1G7). In the very short and slow-growing
rootstock of Trillium (Fig. 169), the base of the leaf-bearing and
flowering stem of tlie season surrounds and covers the terminal bud.
In our common Dentaria or Toothwort, and in Hydrophyllum, the
base of this annual stalk or of the leafstalks partakes in the thicken-
ing, and persists as a part of the rhizoma, in the form of fleshy scales
or tooth-shaped processes. In other scaly rootstocks, these persist-
ent bases of the leaves are thin, and more like bud-scales, and slowly
decay after a year or two. All such markings are vestiges of leaves,
&c, or the scars from which they have fallen or decayed away, and
indicate the nodes. They show that the body that bears them
belongs to the stem ; and not to the root, which is wholly leafless.
Root-stocks branch, just as other stems do, by the development of
lateral -buds from the axils of their scales or leaves. They serve
as a reservoir of nourishing matter, for the maintenance of the an-
nual growth, in the same manner as do thickened roots (145, 146).
When such subterranean stems are thickened at the apex only, they
produce

189. A Tuber. This is usually formed by the enlargement of the
growing bud of a subterranean branch, and the deposition of starch,

170 171

&c. in its tissue. This deposit serves for the nourishment of the
buds (eyes) which it involves, when they develop the following year.
The common Potato offers the most familiar example; and it is

FIG 170. Base of the stem of the Jerusalem Artichoke (Helianthus tuberosus), with its
tubers

FIG 171. A monstrous branch or bud of the Totato, above ground, showing a transition

to the tuber (From the Gardener's Chronicle )

108

THE STEM.

very evident on inspection of the growing plant, that the tubers
belong to branches, and not to the roots. The nature of the potato

is also well shown by an accidental case (Fig. 171),
of the buds or branches above ground thickened and
manifested a strong tendency to develop in the form
of tubers. By heaping the soil around the stems,
the number of tuberiferous branches is increased.
The Jerusalem Artichoke also affords a familiar il-
lustration of the tuber (Fig. 170). A tuber of a
rounded form, and with few buds, or a rhizoma
somewhat shorter and thicker than that in Fig. 1 G9,
effects a transition to

190. A Corm (Cormus), or Solid Bulb. This is a
fleshy subterranean stem, of a rounded or oval figure
and a compact texture ; as in the Arum or Indian
Turnip (Fig. 175), the Colchicum, the Crocus (Fig.
180, 181, 182), the Cyclamen,* &c. Conns have
been termed solid bulbs. But the principal bulk of
a true bulb consists not of stem but of leaves.

* The flattened corm of Cyclamen originates from the dilatation of the radicle
itself. In the Turnip, Beet, and Radish (Fig. 138), this also enlarges with the
proper root, the upper part of which accordingly partakes of the nature of the stem.

FIG 172 The scaly bulb of a Lily. 173 A vertical section of the same, forming the an-
nual stalk. 174 Axillary bulblets of Lilians bulbiferum 175 Corm of Arum tiiphj Hum.

FIG. 176. A radical leaf of the White Lily, with its base thickened into a bulb-scale, cut
nnoss below to s\nw its thickness

BULBS AND BULBLETS.

109

191. A Bulb is a permanently abbreviated stem, mostly shorter
than broad, and clothed with scales, which are imperfect and thick-
ened leaves, or more commonly the thickened and persistent bases
of ordinary leaves (Fig. 17G). In other words, it is a scaly and
usually subterranean bud, with Ihickened scales, and a depressed
axis which never elongates. Its centre or apex develops upward
the herbaceous stalk, foliage, and flowers of the season, and beneath
emits roots. In the bulb, the thickening by the deposition of nutri-
tive matter, stored for future use, takes place in the leaves or scales
it bears, instead of the stem itself, as in the preceding forms. The
scales are sometimes separate, thick, and narrow, as in the Scaly
bulb of the Lily (Fig. 172); sometimes broad and in concentric
layers, as in the Tunicated bulb of the Onion (Fig. 177).

192. BulbletS are small aerial bulbs, or buds with fleshy scales,
which arise in the axils of the leaves of several plants, such as the
common Lilium bulbiferum of the gardens (Fig. 174), and at length
separate spontaneously, falling to the ground, where they strike root,
and grow as independent plants. In the Onion, and other species of
Allium, bulblets are often produced in place of flower-buds. These
plainly show the identity of bulbs with buds.

193. All these extraordinary, no less than the ordinary, forms

FTO 177. Section of a tunicated bulb of the Onion.

FIG. 173. Vertical section of the bulb of the Tulip, showing its stem (a) and buds (6, ej.
FIG. 179. Bulb of a Garlic, with a crop of young bulbs.
FIG. 180. Vertical section of the corm of Crocus : a, new buds.

FIG 181. Vertical section of the corm of Colchicum, with the withered corm of the pr
ceding (a), and the forming one (c) for the ensuing )ear.

10

110

TIIK STEM.

of the stem, grow and branch, or multiply, by the development of
terminal and axillary buds. This is perfectly evident in the rhizoma
and tuber, and is equally the case in the corm and bulb. The stem
of the bulb is usually reduced to a mere plate (Fig. 178, a), which
produces roots from its lower surface, and leaves or scales from the
upper surface. Besides the terminal bud (c), which usually forms
the flower-stem, lateral buds (b, b) are produced in the axils of the
leaves or scales. One or more of these may develop as flowering
stems the next season, and thus the same bulb survive and blossom
from year to year ; or these axillary buds may themselves become
bulbs, feeding on the parent bulb, which in this way is often con-
sumed by its own offspring, as in the Garlic (Fig. 179) ; or, finally
separating from the living parent, just as the bulblets of the Tiger
Lily fall from the stem, they may form so many independent indi-
viduals. So the corm of the Crocus (Fig.
182, 182") produces one or more new ones,
which feed upon and exhaust it, and take its
place ; and the shrivelled remains of the old
corm may be found underneath the new, the
next season. The corm of Colchicum (Fig.
181) produces a new bud on one side at the
base, and is consumed by it in the course of
the season ; the new one, after flowering by
its terminal bud, is in turn consumed by its
own offspring; and so on. In Fig. 181, we
have at one view, a, the dead and shrivelled
corm of the year preceding ; b, that of the
present season (a vertical section).; and c,
is2a the nascent bud for the growth of the ensuing

season. Many of the forms which the stem assumes when above
ground differ as much from the ordinary appearance as do any of
these subterranean kinds, and, in fact, imitate their peculiarities ; a*,
for example, the globular Melon-Cactus and Mamillaria, the colum-
nar Cereus, and the jointed Opuntia or Prickly Pear. These are
remarkably

194. Consolidated Forms Of Vegetation. While ordinary plants are
constructed on the plan of great expansion of surface, these are

FIG 182. Corm of Crocus, the few thin enveloping scales removed, showing the shrivelled
vestige of the last year's corm at the base, and buds developing into new ones on various
parts of its surface. 182". Vertical section of a similar corm, with a terminal and one lateral
bud.

CONSOLIDATED FORMS OF VKGETATION. Ill

formed on the plan of the least possible amount of surface in pro-
portion to their bulk. A green rind serves the purpose of foliage ;
but the surface is as nothing compared with an ordinary leafy plant
of the same amount of vegetable material. This consolidation is
carried to the extreme in the Melon-Cactus, Mamillaria, and the
like, of globular or conn-like shapes ; their spherical figure being
that which exposes the least possible part of the bulk to the air.
Such plants are evidently adapted and des gned for very dry
regions; and in such only are they naturally found. Similarly,
bulbous and corm-bearing plants, and the like, are a form of vege-
tation which in the growing season may in the foliage expand a
large surface to the air and light, while during the period of rest
the living vegetable is reduced to a globular or other form of the
least surface ; and this is protected by its outer coats of dead and
dry scales, as well as by its subterranean situation ; — thus exhibit-
ing another and very similar adaptation to a season of drought.
And such plants mainly belong to countries (such as Southern
Africa, and parts of the interior of Oregon and California) which
have a long hot season, during which little or no rain falls, when,
their stalks and foliage above and their roots beneath being early
cut off by drought, the plants rest securely in their compact bulbs,
filled with nourishment, and retain their moisture with great
tenacity, until the rainy season returns. Then they shoot forth
leaves and flowers with wonderful rapidity, and what was perhaps
a desert of arid sand becomes green with foliage and gay with blos-
soms, almost in a day. This will be more perfectly understood
when the nature and the use of foliage shall have been more fully
considered.

Sect. IV. The Internal Structure of the Stem in
General.

105. Having considered the various external forms and appear-
ances which the stem exhibits, and its mode of increase in length,
our attention may now be directed to its internal structure, and its
mode of increase in diameter.

196. The stem embraces in its composition the various forms of
elementary tissue that have already been described (Chap. I., Sect.
II., III.) ; namely, ordinary cells, woody fibre, and vessels. At

112 the stem.

first, indeed, it consists entirely of parenchyma (SI), which pos-
sesses much less strength and tenacity than woody tissue, and is
therefore inadequate to the purposes for which the stem, in all the
higher plants, is destined. The stem of a Moss or a Liverwort is,
in fact, composed of ordinary cellular tissue alone ; and is therefore
weak and brittle, well enough adapted to plants of humble size,
but not for those which attain any considerable height. Accord-
ingly, as soon as the stems of Phaenogamous plants begin to grow,
and in proportion as the leaves are developed, woody mingled with
vascular tissue is introduced, to afford the requisite toughness and
strength, and to facilitate the rise of the ascending sap. If the
wood accumulates only to moderate extent in proportion to the
parenchyma, the stem remains herbaceous (174) ; if it predominates
and continues to accumulate from year to year, the proper woody
trunk of a shrub or tree is formed.

197. The cellular part of the stem grows with equal readiness,
in whatever direction the forces of vegetation act. It grows verti-
cally, to increase the stem in length, and horizontally, to increase
its diameter. Into this the elongated cells that form the woody
tissue and ducts arc introduced vertically ; they run lengthwise
through the stem and branches. Hence, the latter has been called
the longitudinal, vertical, or perpendicular system (56, 64) ; and
the cellular part, the horizontal system of the stem. Or the stem
may be compared to a web of cloth; the cellular system forming
the woof, and the woody, the warp.

198. The diversities in the internal structure of the stem are
principally owing to the different modes in which the woody or
vertical system is imbedded in the cellular. These diversities are
reducible to two general plans ; upon one or the other of which the
stems of all Flowering plants are constructed. Not only is the
difference in structure quite striking, especially in all stems more
than a year old, but it is manifested in the whole vegetation of the
two kinds of plants, and indicates the division of Phaenogamous
plants into two great classes, recognizable by every eye ; which,
in their fully developed forms, may be represented, one by the Oak
and other trees of our climate, the other by the Palm (Fig. 184).

199. The difference between the two, as to the structure of their
stems, is briefly and simply this. In the first, the woody system is
deposited in annual concentric layers between a central pith and an
exterior bark; so that a cross-section presents a series of rings or

ITS INTERNAL STRUCTURE. 113

circles of wood, surrounding each other and a distinct pith, and all
surrounded by a separable bark. This is the plan, not only of the
Oak, but of all the trees and shrubs of the colder climates. In the
second, the woody system is not disponed in layers, but consists of
separate bundles or threads of woody fibre, &c, running through the
cellular system Avithout apparent order ; and presenting on the cross-
section a view of the divided ends of these threads in the form of
dots, diffused through the whole ; but with no distinct pith, and no
bark which is at any time readily separable from the wood. The
appearance of such a stem, both on the longitudinal and the cross-
section, is shown in Fig. 183 ; it may also be examined in the Cane
or Rattan, the Bamboo, and in the annual stalk of Indian Corn or
of Asparagus. That -of ordinary wood of the first sort is too famil-
iar to need a pictorial illustration.

200. Exogenous Structure. The stem, in th£ first case, increases
in diameter by the annual formation of a new layer of wood, which
is deposited between the preceding layer and the bark ; that is, the
wood increases by annual additions to its outside. Hence, such
stems are said to be Exogenous ; and plants whose stems grow in
this way are called Exogenous Plants, or briefly Exogens ;
that is, as the term literally signifies outside-growers.

201. Endogenous Structure. In the second case, the new woody
matter is intermingled with the old, or deposited towards the centre,
which becomes, more and more occupied

with the woody threads as the stem grows
older ; and increase in diameter, so far as
it depends on the formation of new wood,
generally takes place by the gradual dis-
tention of the whole. Accordingly, these
stems are said to exhibit the Endoge-
nous structure or growth ; and such plants 183
are called Endogenous Plants, or Endogens ; literally, inside-
growers.

202. The two great classes of Phcenogamous plants, indicated by
this difference in the stem, are distinguishable even in the embryo
state, by differences quite as marked as those which prevail in their
whole port and aspect. The embryo of all plants that have en-
dogenous stems bears only a single cotyledon ; hence, Endogens are
aho called Monocotyledonous Plants (128). The embryo of

FIG. 1S3. Section (longitudinal and transverse) of a Palm-stem.

10*

m

THE STEM.

plants "with exogenous stems bears a pair of cotyledons and unfolds
a pair of seed-leaves in germination (Fig. 106, 12,3) ; hence, Exogens
are likewise called Dicotyledonous Plants.

Sect. V. The Endogenous or Monocotyledonous Stem.

203. Endogens, or Inside-growers, although they have many
humble representatives in Northern climes, yet only attain their full
characteristic devel-

'hlfp,.

opment, and display
their noble arbores-
cent forms, under a
tropical sun. Yet
Palms — the type of
the class — do ex-
tend as far north in
this country as the
coast of North Caro-
lina (the natural lim-
it of the Palmetto,
Fig. 184) ; while in
Europe the Date
and the Chamaerops
thrive in the warm-
er parts of the
European shore of
the Mediterranean.
The manner of their
growth gives
them a strik-
ing appear-
ance ; their
trunks being
unbranched, 184

cylindrical columns, rising majestically to the height of from thirty
to one hundred and fifty feet, and crowned at the summit with a
simple cluster of peculiar foliage. Their internal structure is equal-
ly different from that of ordinary wood.

FIG. 184. The Chamajivps Palmetto, in various stages, and the Yucca Draconis.

ENDOGENOUS STRUCTURE.

115

204. The stem of an Endogen, as already explained (199), offers
no manifest distinction into bark, pith, and wood ; and the latter is not
composed of concentric rings or layers. But it consists of bundles of
woody and vascular tissue, in the form of fibres or threads, which are
imbedded, with little apparent regularity, in cellular tissue ; and the
whole is enclosed in an integument, which does not strictly resemble
the bark of an Exogenous plant, inasmuch as it does not increase
by layers, and is never separable from the wood. The fibrous
bundles which compose the wood, and which consist of a mass of
woody fibres surrounding several vessels, are distributed throughout
the cellular system of the stem, but most abundantly towards the
circumference. Each bundle usually contains all the elements of
the wood of the exogenous stem ; namely, vessels, proper Avoody
tissue, and bast-cells. The bundles often may be traced directly
from the base of the leaves down through the stem, some of them
to the roots in a young plant, while others, curving outwards, lose
themselves in the cortical integument,

or rind. As the stem increases, new
bundles, springing from the bases of
more recently developed leaves, are at
first directed towards the centre of the
stem, along which they descend for
some distance, growing more slender
in their course, and then, curving out-
wards, mostly terminate in the rind.
It is partly in consequence of the co-
hesion of these obliquely descending
fibres to the false bark, that the latter
cannot, as in Exogens, be separated
from the wood beneath. The manner
in which the woody threads are consequently interwoven is shown
in Fig. 185. The Palm-like Yuccas of the Southern States offer
beautiful illustrations of the kind.

205. Endogenous stems, instead of having the oldest and hardest
wood at the centre and the newest and softest at the circumference,
as in ordinary trees, are softest towards the centre and most compact
at the circumference. They increase in diameter with the increas-
ing number of woody bundles (which multiply as new leaves are

FTG 185. Vertical and transverse section of a young endogenous stem, showing the curv-
ing of tae fibres.

116 THE STEM.

produced), as long as the rind is capable of distention. In some
instances, as in the arborescent Yuccas and the Dracaenas or Dragon-
trees, the rind remains soft and capable of unlimited growth ; but in
the Palms, and in most woody Endogens, it soon indurates, and the
stem consequently increases no further in diameter. The wood of
the lower part of such stem is more compact than the upper, being
more filled with woody bundles, and the rind is firmer, from the
greater number of ligneous fibres which terminate in it, and from
its proper induration.

206. Palms generally grow from the terminal bud alone, and
perish if this bud be destroyed ; they grow slowly, and bear their
foliage in a cluster at the summit of the trunk, which consequently
forms a simple cylindrical column. But in some instances two or
more buds develop, and the stem branches, as in the Doum Palm of
Upper Egypt, and in the Pandanus, or Screw-Pine (Fig. 140),
which belongs to a family allied to Palms : in such cases the
branches are cylindrical. But when lateral buds are freely devel-
oped (as in the Asparagus), or the leaves are scattered along the
stem or branches (as in the Bamboo, Maize, &c), these taper up-
wards, just as in Exogens. A particular comparison of the structure
and growth of the Endogenous stem with the Exogenous cannot be
instituted until the latter is explained in detail.

Sect. VI. The Exogenous or Dicotyledonous Stem.

207. Sixce the Exogenous class is by far the larger in every part
of the world, and embraces all the trees and shrubs with which we
are familiar in the cooler climates, the structure of this kind of stem
demands more detailed notice. To obtain a true and clear idea of
its internal structure, we should commence at its origin and follow
the course of development.

208. In the embryo, or at least at some period antecedent to
germination, the rudimentary stem is entirely composed of paren-
chyma. But as soon as it begins to grow, some of the cells begin to
lengthen into tubes, to be marked with transverse bai-s or spiral
lines, and thus give rise to ducts or vessels (57-60) ; these form a
small and definite number of bundles or threads, say four equidistant
ones in the first instance, as in the Sugar Maple : surrounding these,
other slender cells of smaller calibre, and destitute of markings,

EXOGENOUS STRUCTURE.

117

soon appear, and form the earliest woody tissue. As. the rudiments
of the next internode and its leaves appear, two or four additional
threads of vascular tissue appear in the stem below, in the paren-
chyma between the earliest ones, and are equally surrounded with
forming woody tissue. At an early stage, therefore, the developing
stem is seen to be traversed by several bundles of woody tissue, with
some vessels imbedded ; and these, as they increase and enlarge, run
together so as to make up a woody zone (or, as seen in the cross-
section, a ring), enclosing the central part of the parenchyma within
it, and itself enclosed by the external parenchyma. Thus a zone or
layer of wood is formed, which is so situated in the original homo-
geneous cellular system as to divide it into two parts ; namely, a
central portion, which forms the pith, and an exterior portion, which
belongs to the bark. The whole is of course invested by the skin
or epidermis, which covers the entire surface of the plant. The
way in which the layer of wood thus originates is somewhat rudely
illustrated by the annexed diagrams (Fig. 186- 188). The several

woody masses, or wedges, are separated from each other by lines or
bands of the original cellular tissue, which pass from the pith to the
bark, and which necessarily become narrower and more numerous as
the woody bundles or wedges increase in size and number. These
bands are the

209. Medullary Rays. These form the radiating lines that the
cross-section of most exogenous wood so plainly exhibits, especially
that of the Oak, Plane, &c. They consist of parenchyma, more

FIG 186. Plan of a cross-section of a forming seedling stem, showing the manner in which
the young wood is imbedded in the cellular system.

FIG 187. The same at a later period, the woody bundles increased so as nearly to fill the
circle.

FIG 188. The same at the close of the season, where the wood has formed a complete
circle, sep.irat;ng the pith from the bark, except that they are still connected by narrow por-
tions of tho cellular system (the meUullaiy rays) which radiate from the pith to the bark.

118

or less flattened by the pressure of the woody wedges, and they
serve to keep up the communication between the pith and the
bark.

210. The First Year's Growth of an exogenous stem accordingly con-
sists of three principal parts, viz.: 1st, a central cellular portion, or
Pith; 2d, a zone of Wood; and 3d, an exterior cellular portion, or

Bark. These several
parts are displayed
in Fig. 189-191, as
they occur in a woody
stem a year old.

211. The Pith (il^-

dulla) consists en-
tirely of soft cellular
tissue, or parenchy-
ma* (51), which is
at first gorged with
sap. Many stems
expand so rapidly in
diameter during their
early growth, that
they become hollow,
the pith being torn
away by the disten-
tion, and its remains
forming a mere lin-
ing to the cavity.
In the Walnut and
the Poke (Phytolac-

* In rare instances a few threads of woody tissue and vessels, arc found dis-
persed through the pith, presenting a somewhat remarkable anomaly. This
occurs in Aralia raccmosa, and more strikingly in Oxybaphus, Mirabilis or
Tour-o'clock, and other Nyctaginaccre.

FIG. 189 Longitudinal and transverse section of a stem of the Soft Maple (Acer dasycar-
puni), at the close of the first years growth ; of the natural size

FIG 190. Portion of the same, magnified, showing the cellular pith, surrounded by the
wood, and that enclosed by the bark

FIG. 191 More magnified slice of the same, reaching from the bark to the pith : a, part of
the pith ; h, vessels of the medullary sheath ; r, the wood ; del, dotted ducts in the wood ; ee,
annular duets ; _/, the liber, or inner fibrous bark ; g-, the cellular envelope, or green bark ; A,
the corky envelope ; i, the skin or epidermis ; &, one of the medullary rays, seen on the trans-
verse section.

EXOGENOUS STRUCTURE.

119

ca) it is early separated into a series of horizontal plates. As the
stem grows older the pith becomes dry and light, its cells filled with
air only ; and then it is of no further use to the plant.

212. The Wood consists of proper woody tissue (53), among which
the vascular is more or less copiously mingled, principally in the
form of dotted ducts (Fig. 191, d), or occasionally some annular
ducts (e), &c. The dotted ducts are of so considerable calibre, that
they are conspicuous to the naked eye in many ordinary kinds of
wood, especially where they are accumulated in the inner portion of
each layer, as in the Chestnut and Oak. In the Maple, Plane, &c,
they are rather equably scattered through the annual layer, and are
of a size so small, that they are not distinguishable by the naked eye.
— Next the pith, i. e. in the very earliest formed part of the wood,
some spiral ducts are uniformly found (Fig. 191, b), and this is the
only part of the exogenous stem in which these ordinarily occur.
They may be detected by breaking a woody twig in two, after divid-
ing the bark and most of the wood by a circular incision, and then
pulling the ends genlly asunder, when their spirally coiled fibres are
readily drawn out as gossamer threads. As these spiral ducts form
a circle immediately surrounding the pith, they form what has been
termed the Medullary Sheath. This is no special organ, and
hardly requires a special name, since it merely represents the earli-
est-formed vascular tissue of the stem.

213. The vertical section in Fig. 191 divides one of the woody
wedges ; and therefore the medullary rays do not appear. But in

■

FIG 192 Vertical section through the wood of a branch of the Maple, a 3-ear old : so as to
show one of the medullary rays, passing transversely from the pith (j>) to the bark (6): mag-
nified But a section can seldom be made so as to show one unbroken plate stretching across
the wood, as in this instance

FIQ 193 A vertical section a-ross the ends of the medullary rays ; magnified.

120 THE STEM.

the much more magnified Fig. 192, the section is made so as to
show the surface of one of these plates, and one of the Medullary
Rays passing horizontally across it, connecting the pith (p) with
the bark (b). These medullary rays form the silver-grain, (as it
is termed,) which is so conspicuous in the Maple, Oak, &c, and
which gives the glimmering lustre to many kinds of wood when cut
in this direction. But a section made as a tangent to the circum-
ference, and therefore perpendicular to the medullary rays, brings
their ends to view, as in Fig. 193 ; much as they appear when seen
on the surface of a piece of wood from which the bark is stripped.
They are here seen to be composed of parenchyma, and to represent
the horizontal system of the wood, or the woof, into which the ver-
tical woody fibre, &c, or warp, is interwoven. The inspection of a
piece of oak or maple wood at once shows the pertinency of this
illustration.

214. The Bark, in a stem of a year old, must next be considered.
At first it consists of simple parenchyma, {indistinguishable from
that of the pith, except that it assumes a green color when exposed
to the light, from the production of chlorophyll (92) in its cells. But
during the formation of the wood of the season, an analogous forma-
tion occurs in the bark. The inner portion, next the wood, has
woody tissue formed in it, and becomes

215. The Liber, or Inner Bark (Fig. 191,/). The fibre-like cells,
which give to the inner bark of those plants that largely contain
them its principal strength and toughness, are of the kind already
described under the name of bast-cells or bast-tissue (55). They are
remarkable for their length, flexibility, and the great thickness of
their walls. They form in bundles, or in bands separated by exten-
sions of the medullary rays, one accordingly corresponding to each
of the woody plates or wedges ; or sometimes (as in Negundo, Fig.
194, 195) they are confluent into an unbroken circle round the
whole circumference. Complete and well-developed liber, like that of
the Basswood, consists of three elements, viz.: 1. bast-cells or fibres ;
2. large and more or less elongated cells, with thinner walls variously
marked with transparent spots, appearing like perforations, and
usually traversed by an exceedingly minute net-work ; and 3. cells
of parenchyma. The liber has received the technical name of
Endophlceum (literally inner bark). In most woody stems the
exterior part of the bark, in which no woody tissue occurs, is early
distinguishable into two parts, an inner and an outer. The former is

EXOGENOUS STRUCTURE.

121

216. The Cellular Envelope, or Green Layer (Fig. 191, g), also called,
from its' intermediate position, the Mesophl<etjm. This is com-
posed of loose parenchyma, with thin walls, much like the green
pulp of leaves, and containing an equal abundance of chlorophyll.
It is the only part of the bark that retains a green color. In woody
stems this is soon covered with

217. The Corky Envelope, or Epiphlozum: (Fig. 191, h), which

gives to the twigs of trees and shrubs the hue peculiar to each spe-
cies, generally some shade of ash-color or brown, or occasionally of
much more vivid tints. It is this tissue, which, taking an unusual
development, forms the cork of the Cork-Oak, and those corky ex-
pansions of the bark which are so conspicuous on the branches of

me*

mm

HBP

FIG. 194. Portion of a transverse section, and 195. a corresponding vertical section, magni-
fied, reaching from the pith, p, to the epidermis, e, of a stem of Ncgundo, a year old : E, the
bark ; TV, the wood ; and C, the cambium-layer, as found in February. The references are in
the text above ; except mr, portion of a medullary ray, seen on the vertical section, where it
runs into the pith : dd, doUed ducts : d, the inner part of the cambium-layer, which begins
the new layer of wood. In this tree, we find a thick layer of parenchyma (I) inside of the bast-
tissue, and therefore belonging to the liber. No bast-tissue is formed in it the second year.
11

122 THE STEM.

the Sweet Gum (Li qui (lumbar), and on some of our Elms (Ulmus
alata and racemosa). It also forms the paper-like, exfoliating layers
of Birch-bark. It is composed of laterally flattened parenchymatous
cells, much like those of the Epidermis (G9, Fig. 191, i), which
directly overlies it, and forms the skin or surface of the stem.

218. The elements of an exogenous stem of a year old, especially
in a woody plant, accordingly are these, proceeding from the centre
towards the circumference : —

I. In the Wood :

1. The Pith, belonging to the cellular system (Fig. 194, 195, p).

2. The Medullary Sheath, ms, ) which belong to the woody or

3. The Layer of Wood, W, w, ) longitudinal system.

4. The Medullary Rays, mr, a part of the cellular system.

II. In the Bark :

5. The Liber, I ; its bast-tissue, h, belongs to the woody system.
G. The Outer Bark, belonging wholly to the cellular system, and

composed of two parts, viz. : 1st, the Green or Cellular En-
velope, ge, and 2d, the Corlcy Envelope, ce.
7. The Epidermis, e, or skin, Avhich invests the whole.

219. An herbaceous stem does not essentially differ from a woody
one of this age, except that the wood forms a less compact or thinner
zone ; and the whole perishes, at least down to the ground, at the
close of the season. But a woody stem makes provision for contin-
uing its growth the second year. As the layer of wood continues to
increase in thickness throughout the season, by the multiplication of
cells on its outer surface, between it and the bark, and when growth
ceases this process of cell-multiplication is merely suspended, so
there is always a zone of delicate young cells interposed between the
wood and the bark. This is called the

220. Cambium-Layer, (Fig. 194, 195, C). It is charged with or-
ganizable matter (protoplasm, dextrine, &c.) in the form of a mu-
cilage, which is particularly abundant in the spring when growth
recommences. This mucilaginous matter was named Cambium by
the older botanists; who supposed — as is still generally thought —
that the bark, then so readily separable, really separated from the
wood in spring, that, a quantity of rich mucilaginous sap was poured
out between them, and that this sap, or cambium, was organized
into a tissue, the inner part becoming new Avood, the outer, new
bark. But delicate slices will show that there is then no more inter-
ruption of the wood and inner bark than at any other season ; that

EXOGENOUS STRUCTURE. 123

the two are always organically connected by an extremely delicate
tissue of young and vitally active cells, just in the state in which
they multiply by division (33). The bark, indeed, is very readily
detached from the wood in spring, because the cambium-layer is then
gorged with sap ; but the separation is effected by the rending of
a delicate forming tissue. And if some of this apparant mucilage be
scraped off from the surface of the wood, and examined under a good
microscope, it will be seen to be a thin stratum of young wood-cells,
with the ends of medullary rays here and there interspersed, and
appearing much as in Fig. 193, only the young wood-cells are mostly
shorter. The inner portion of the cambium-layer is therefore nas-
cent wood, and the outer is nascent bark. And it is by the growth
of the cambium-layer, renewed year after year, that the

221. Animal Increase Of the Wood of Exogenous plants is effected.
As the cells of this layer multiply, the greater number lengthen ver-
tically into prosenchyma or woody tissue ; while some are trans-
formed into ducts, and others, remaining as parenchyma, continue the
medullary rays or commence new ones. In this way a second layer
of wood is formed the second season, over the whole surface of the
former layer and between it and the bark, and continuous with the
woody layer of the new roots below and of the leafy shoots of the
searon above. Each succeeding year another layer is added to the
wood in the same manner, coincident with the growth in length by
the development of the buds. A cross-section of an exogenous stem,
therefore, exhibits the wood disposed in concentric rings between
the bark and the pith ; the oldest lying next the latter, and the
youngest occupying the circumference. Each layer being the pro-
duct of a single year's growth, the age of an exogenous tree may, in
general, be correctly ascertained by counting the rings in a cross-
section of the trunk.*

* The annual layers are most distinct in trees of temperate climates like ours,
where there is a prolonged period of total repose, from the winter's cold, fol-
lowed by a vigorous resumption of vegetation in spring. In tropical trees they
are rarely so well defined ; but even in these there is generally a more or less
marked annual suspension of vegetation, occurring, however, in the dry and
hotter, rather than in the cooler season. There arc numerous cases, moreover,
in which the wood forms a uniform stratum, whatever be the age of the trunk,
as in the arborescent species of Cactus ; or where the layers are few and by no
means corresponding with the age of the trunk, as in the Cycas.

In many woody climbing or twining stems, such as those of Clematis, Aristo-

124 THE STEM.

222. The Limitation of the Annual Layers results from two or more

causes, separate or combined. In oak and chestnut wood, and the
like, the layers are strongly defined by reason of the accumulation of
the large dotted ducts, here of extreme size and in great abundance,
in the inner portion of each layer, where their open mouths. on the
cross-section are conspicuous to the naked eye, making a strong con-
trast between the inner porous, and the exterior solid part of the
successive layers. In Maple and Beech wood, however, the ducts
are smaller, and are dispersed throughout the whole breadth of the
layer ; and in coniferous wood, viz. that of Pine, Cypress, &c, there
are no ducts at all, but only a uniform woody tissue of a peculiar
sort (46, 54). Here the demarcation between two layers is owing
to the greater fineness of the wood-cells formed at the close of the
season, viz. tho^e at the outer border of the layer, while the next
layer begins, in its vigorous vernal growth, with much larger cells,
thus marking an abrupt transition from one layer to the next. Be-
sides being finer, the last wood-cells of the season are often flattened
laterally, more or less.

223. Each layer of wood, once formed, remains unchanged in posi-
tion and dimensions. But in trunks of considerable age, the older
layers generally undergo more or less change in color and density,
distinguishing the wood into two parts, viz.

224. Sap-W00(l and Ileart-WOOd. In the germinating plantlet and in
the developing bud, the sap ascends through the whole tissue, of
whatever sort ; at first through the parenchyma, for there is then no
other tissue ; and the transmission is continued through it, especially
through its central portion, or the pith, in the growing apex of the
stem throughout. But in the older parts below, the pith, eoon
drained of sap, becomes filled with air in its place, and thenceforth it
bears no part in the plant's nourishment. As soon as wood-cells and
ducts are formed, they take an active part in the conveyance of sap ;

lochia Sipho, and Menispermum Canadense, the annual layers are rather obscure-
ly marked, while the medullary rays are unusually broad ; and the wood therefore
forms a series of separable wedges disposed in a circle around the pith. In the
stem of one of our Trumpet-creepers (the Bignonia capreolata) the annual rings,
after the first four or five, arc interrupted in four places, and here as many broad
plates of cellular tissue, belonging properly to the bark, arc interposed, passing
at right angles to each other fiom the circumference towards the centre, so thai:
the transverse section of the wood nearly resembles a Maltese cross. But these
are all exceptional cases, which scarcely require notice in a general view.

SAV-WOOD AND IIEAKT-WOOD

125

for which their tubular and capillary character is especially adapted.
But the ducts in older parts, except when gorged with sap, contain
air alone ; and in woody trunks the sap continues to rise year after
year, to the places where growth is going on, mainly through the
proper woody tissue of the wood. In this transmission the new layers
are most active, and these are in direct communication with the new
roots on the one hand and with the buds or shoots and leaves of the
season on the other So, by the formation of new annual layers out-
side of them, the older ones are each year removed a step farther
from the region of growth; or rather the growing stratum, which
connects the fresh rootlets that imbibe with the foliage that elabo-
rates the sap, is each year removed farther from them. The latter,
therefore, after a few years, cease to convey sap, as they have long

196 1S8

FIG. 196 Magnified cross-section of a portion of woody tissue of White Oak, a year old.
197. A longitudinal as well as cross section of the same, a little iiigher magnified, a, a. Por-
tions of one of the smaller medullary rays

FIG. 198 Magnified cross-section of woody tissue from the same stem, taken from a layer
of heart-wood, 24 years old: b, ducts : a, portion of one of the minuter medullary rays. i99.
Combined cross and longitudinal section of the same : a, tissue of a medullary ray.
11*

126 THE STEM.

before ceased to take part in any vital operations. The cells of the
older layers, also, commonly have thicker walls and smaller calibre
than those of the newer, — as here shown in Fig. 198, 199, compared
with Fig. 196, 197, — owing to the greater amount of thickening or-
ganic materials (43) mingled with encrusting mineral matters intro-
duced with the water imbibed by the roots (93) which have been de-
posited upon them from within. This older, more solidified, and harder
wood, which occupies the centre of the trunk, and is the part princi-
pally valuable for timber, &c, is called Heart- wood, or Duramen :
while the newer layers of softer, more open, and bibulous wood, mote
or less charged with sap, receive the name of Sap-woop, or Albur-
num. The latter name was given by the earlier physiologists in allu-
sion (o its white or pale color. In all trees which have the distinction
between the sap-wood and heart-wood well marked, the latter acquires
a deeper color, and that peculiar to the species, such as the dark brown
of the Black Walnut, the blacker color of the Fbony, the purplish-red
of Red Cedar, and the bright yellow of the Barberry. These colors
are owing to special vegetable products mixed with the incrusting
matters ; but sometimes the hue appers to be rather an alteration of
the lignine with age. In the Red Cedar, the deep color belongs
chiefly to the medullary rays. In many of the softer Avoods, there is
little thickening of the cell-walls, and little change in color of the
heart-wood, except from incipient decay, as in the White Pine, Pop-
lar, Tulip-tree, &c. The heart-wood is no longer in any sense a
living part ; it may perish, as it frequently does, without affecting the
life or health of the tree.

225. The Bark is much more various in structure and growth than
the wood : it is also subject to grave alterations with advancing age,
on account of its external position, viz. to distention from the con-
stant1-' increasing diameter of the stem within, and to abrasion and
decay from the influence of the elements without. It is never entire,
therefore, on the trunks of large trees ; but the dead exterior parts,
no longer able to enlarge with the enlarging wood, are gradually
fissured and torn, and crack off in layers, or fall away by slow decay.
So that the bark of old trunks bears but a small proportion in thick-
ness to the wood, even when it makes an equal amount of annual
growth.

226. The three parts of the bark (214-217), for the most part
readily distinguishable in the bark of young shoots, grow indepen-
dently, each by the addition of new cells to its inner face, eo long as

THE BARK. 127

it grows at all. The green layer does not increase at all after the
first year ; the opaque corky layer soon excludes it from the light ;
and it gradually perishes, never to be renewed. The corky layer
commonly increases for a faw years only, by the formation of new
tabular cells : occasionally it takes a remarkable development, form-
ing the substance called Cork, as in the Cork Oak. A similar growth
occurs on the bark of several

species of Elm, of our Liquid- g ^ <z=es J^^/gjSjSgjg

ambar or Sweet-Gum, &c, pro- l^m^iMSMM&
ducing thick corky plates on the «i^=^^^^lEB3I^!si^
branches. In the White and Pa- 4 ^Sc^^^^^^^S"

ireh, thin layers, of a very
durable nature, are formed for
a great number of years ; each
layer of tabular and firmly cohe-
rent cells (Fig. 200, a) alternates
with a thinner stratum of delicate,
somewhat cubical and less compact cells (i), which break up into a
fine powder when disturbed, and allow the thin, paper-like plates to
exfoliate.

227. The liber, or inner bark (215), continues to grow through-
out the life of the tree, by an annual addition from the cambium-
layer applied to its inner surface. Sometimes the growth is plainly
distinguishable into layers, corresponding with or more numerous
than the annual layers of the wood : often, there is scarcely any
trace of such layers to be discerned. In composition and appearance
the liber varies greatly in different plants* especially in trees and
shrubs. That of Bass-wood or Linden, and of other plants with
a similar fibrous bark, may be taken as best representing the liber.
Here it consists of strata of very thick-walled cells alternating with
thin-walled cells. The thick-walled cells are bast-cells (55, Fig. 49,
53), are much elongated vertically, and form the fibrous portion of

* The best account of the liber that has yet been given is that by Mold,
in the Botanische Zeitung, Vol. 13, p 873 (1855), of which a French translation is
published in the Annates dts Sciences Nat ur tiles, scr. 4, Vol. 5, p. 141, ct scq.
(1856).

FIG 200 Transverse section of a minute portion of White Tirch bark, the corky layer
highly magnified : a, the firm, tabular cells, 6, delicate thiu-walled culls which separate the
papery plates. (After Link )

128

THE STEM.

the bark. The thin-walled cells are those of ordinary parenchyma,
mingled, at the inner part of each stratum, with larger and longer
ones, marked (on some sides at least) with the thin and reticulated
spots or punctuations already described (215). These last may be
termed the proper cells of the liber, as they are peculiar to this part
of the bark, are seldom if ever absent, they contain an abundance of
mucilage and proteine, and in all probability they take the principal
part in the descending circulation of the plant, if it may so be called,
i. e. in conveying downwards and distributing the rich sap which has
been elaborated in the foliage. It is evident that the bast-cells,
which in Linden (Fig. 53) are seen to be almost solid, are not
adapted to this purpose.

228. That bast-cells are not an essential part, is further evident
from the fact, that they are altogether Avanting in the bark of some
plants, and are not produced after the first year in many others. The
latter is the case in Negundo, where abundant bast-cells, like those
of Bass-wood, compose the exterior portion of the first year's liber
(Fig. 194, 195, b), but none whatever is formed in the subsequent
layers. In Beeches and Birches, also, a few bast-cells are produced
the first year, but none afterwards. In Maples a few are formed in
succeeding years. . In the Pear bast-cells are annually formed, but
in very small quantity, compared with the parenchymatous part of
the liber. In Pines, at least in White Pines, the bark is nearly as
homogeneous as the wood, the whole liber, except what answers to
the medullary rays, consisting of one kind of cells, resembling those

of bast or of wood in form, but agree-
ing with the proper liber-cells in their
structure and markings. Although
the liber of Birch produces no bast-
cells after the first year, it abounds
in short cells equally solidified by in-
ternal deposition, and of a gritty tex-
<*rrvW tur6j which might be mistaken for

201 „ bast-cells on the cross-section (Fig.

201). A longitudinal section discloses the difference.

229. The bark on old stems is constantly decaying or falling away
from the surface, without any injury to the tree ; just as the heart-
wood may equally decay within without harm, except by mechani-

FIG 201. Cross-section of a cluster of solidified and indurated cells from t'-ie liber of the
White Birch. (After Link )

THE LIVING PARTS OF A TREE. 129

cally impairing the strength of the trunk. Great differences are
observable as to the time and manner in which the older bark
of different shrubs and trees is thrown off, according to the struc-
ture in each species. Some trees and shrubs have their trunks in-
vested with the liber of many years' growth, although only the in-
nermost layers are alive ; in others it scales off much earlier. On
the stems of the common Honeysuckle, of the Nine-Bark (Spirsea
opulifolia), and of Grape-vines (except of our Muscadine Grape),
the liber lives only one season, and is detached the following year,
hanging loose in papery layers in the former species, and in fibrous
shreds in the latter.

230. While the newer layers of the wood abound in crude sap,
which they convey to the leaves (224), those of the inner bark
abound in elaborated sap (79, 227), which they receive from the
leaves and convey to the cambium-layer or zone of growth. The
proper juices and peculiar products of plants (88) are accordingly
found in the foliage and the bark, especially in the latter. In the
bark, therefore, (either of the stem or of the root,) medicinal and
other principles are usually to be sought, rather than in the wood.
Nevertheless, as the wood is kept in connection with the bark by
the medullary rays, many products which probably originate in the
former are deposited in the wood.

231. The Living Paris of a Tree or Shrub, of the Exogenous kind, are
obviously only these:— 1st. The summit of the stem and branches,
with the buds which continue them upwards and annually develop
the foliage. 2d. The fresh tips of the roots and rootlets annually
developed at the opposite extremity. 3d. The newest strata of wood
and bark, and especially the interposed cambium-layer, which, annu-
ally renewed, maintain a living communication between the rootlets
on the one hand and the buds and foliage on the other, however dis-
tant they at length may be. These are all that is concerned in the
life and growth of the tree ; and these are annually renewed. The
branches of each year's growth are, therefore, kept in fresh commu-
nication, by means of the newer layers of wood, with the fresh
rootlets, which are alone active in absorbing the crude food of the
plant from the soil. The fluid they absorb is thus conveyed directly
to the branches of the season, which alone develop leaves to digest
it. And the sap they receive, having been elaborated and converted
into organic nourishing matter, is partly expended in the upward
growth of new branches, and partly in the formation of a new layer

130 THE ST KM.

of wood, reaching from the highest leaves to the remotest rootlets.*
As the exogenous tree, therefore, annually renews its buds and

* The layers of wood and bark, by which tbo exogenous stem annually in-
creases in diameter, arc formed by the multiplication of the cells of the cambium-
layer throughout its whole extent. That the organic material to supply this
growth in ordinary vegetation descends in the bark, for the most part, and that
the order of growth in the formation of wood is from above downwards, and
also the general dependence of this growth upon the action of the foliage, may
be inferred from a variety of facts and considerations. The connection of the
wood with the leaves is shown : — (I.) By tracing the threads of soft woody
Endogens, such as Yucca, directly from the base of the leaf into the stem, and
thence downward to their termination, towards which they become attenuated,
lose their vessels, and are finally reduced to slender shreds of woody tissue.
(2.) The amount of wood formed in a stem or branch, other things being equal,
is in a relation to the number and size of the leaves it bears ; its amount in any
portion of the branch is in direct proportion to the number of leaves above .that
portion. Thus, when the leaves are distributed along a branch, it tapers to the
summit, as in a common Reed or a stalk of Indian Corn ; when they grow in a
cluster at the apex, it remains cylindrical, as in a Palm (Fig. 184). Consequently
the increase of the trunk in diameter directly corresponds with the number and
vigor of the branches. The greater the development of vigorous branches on a
particular side of a tree, the more wood is formed, and the greater the thickness
of the annual layers on that side of the trunk. (3.) In a seedling, the wood
appears in proportion as the leaves arc developed. (4.) If a young branch be
cut off just below a node (156), so as to leave an internodc without leaves or
bud, little or no increase in diameter will ordinarily take place clown to the first
leaf below. But if a bud be inserted into this naked internodc, as the bud de-
velops, increase in diameter, with the formation of new wood, recommences.
That the formation proceeds from above downwards, or that the elaborated sap
which furnishes the material for the growth is diffused from above downwards,
appears from the effect of a ligature around exogenous stems, or of removing a
ring of bark. It is a familiar fact, that, when a ligature is closely bound around
a growing exogenous stem, the part above the ligature swells, and that below
docs not. Everyone may have observed the distortions that twining stems thus
accidentally prodncc upon woody exogenous trunks, causing an enlargement on
the upper side of the obstruction. When the stem is girdled, by removing a
ring of bark so as completely to expose the surface of the wood, the part above
the ring enlarges in the same manner ; that below docs not. until the incision is
healed. The wood of the roots is manifestly formed in a descending direction.
But this is continuous with that of the stem ; and its first layer, the extension of
the wood of the radicle into the primary root, agrees in composition with the
wood of the succeeding layers in the stem, having no spiral vessels, but only
ducts. Still, whatever analogy there may be between the growth of the wood
in the stem and of roots, there is no real basis for the ingenious conception of
Thouars and of Gaudichaud, that wood is the roots of buds or leaves, or that
it is absolutely dependent upon them for its formation.

COMPOSITE NATURE OK A PLANT. 131

leaves, its wood, bark, and roots, — everything, indeed, that is con-
cerned in its life and growth, — there seems to be no reason, no
necessary cause inherent in the tree itself, why it may not live in-
definitely. Accordingly, some trees are known to have lived for
twelve hundred years or more ; and others now survive which are
probably above two thousand years old, and perhaps much older *
This longevity ceases to be at all surprising when we consider, that,
although the tree or herb is in a certain sense an individual, yet it
is not an individual in the sense that a man or any ordinary animal
is. Viewed philosophically,

232. The Plant is a Composite Being, or community, lasting, in the
case of a tree especially, through an indefinite and often immense
number of generations. These are successively produced, enjoy a
term of existence, and perish in their turn. Life passes onward
continually from the older to the newer parts, and death follows,
with equal step, at a narrow interval. No portion of the tree is now
living that was alive a few years ago ; the leaves die annually and
are cast off, while the internodes or joints of stem that bore them, as
to their Avood at least, buried deep in the trunk, under the wood
of succeeding generations, are converted into lifeless heart-wood, or
perchance decayed, while the bark that belonged to them is thrown
off from the surface. It is the aggregate, the blended mass alone,
that long survives. Plants of single cells, and of a definite form,
alone exhibit complete individuality ; and their existence is ex-
tremely brief. The more complex vegetable of a higher grade is
not to be compared with the animal of the highest organization,
where the offspring always separates from the parent, and the indi-
vidual is simple and indivisible. But it is truly similar to the branch-
ing or arborescent coral, or to other compound animals of the lowest
grade, where successive generations, though capable of living inde-
pendently and sometimes separating spontaneously, yet are usually
developed in connection, blended in a general body, and nourished
more or less in common. Thus the coral structure is built up by
the combined labors of a vast number of individuals, — by the suc-

* The subject of the longevity of trees has been ably discussed by Dc Can-
dolle, in the Bibhothcque Universelk of Geneva, for May, 1831, and in the second
volume of his Physiologie Vcye'tale : also, more recently, by Professor Alphonse
Dc Candolle. In this country, an article on the subject has appeared in tho
North American Review, for July, 1844.

132 THE STEM.

cessive labors of a great number of generations. The surface or the
recent .shoots alone are alive ; and here life is superficial, all under-
neath consisting of the dead remains of former generations. The
arborescent species are not only lifeless along the central axis, but
are dead throughout towards the bottom : as, in a genealogical tree,
only the later ramifications are among the living. It is the same
■with the vegetable, except that, as it ordinarily imbibes its nourish-
ment mainly from the soil through its roots, it makes a downward
growth also, and, by constant renewal of fresh tissues, maintains the
communication between the two growing extremities, the buds and
the rootlets.

233. Individuality being imperfectly realized in the vegetable
kingdom, the question as to what in the Phamogamous plant best
answers to the animal individual is speculative, rather than practical,
and may be more appropriately noticed in another place. (Part II.
Chap. I.)

234. Comparison of Endogenous with Exogenous Structure. The woody

bundles of an exogenous stem (Fig. 18G-188) continue to grow on
the outer side as long as the plant lives. In woody trunks they at
once become wedges with the point next the pith, and growth pro-
ceeds indefinitely by the stratum of perpetually renewed tissue on
the outer face between the wood and the bark. Each wedge is
separated from its neighbor on both sides by an interposed medul-
lary ray, and is composed of wood on the inner side, liber on the
outer, and cambium or forming tissue between. Now each thread
or bundle of endogenous wood (204) is composed of similar or anal-
ogous parts, sometimes irregularly intermixed, but more commonly
similarly disposed. That is, the section of one of these threads ex-
hibits woody tissue and one or two spiral vessels on its inner border,
answering to the proper wood, and very thick-walled elongated cells
on its outer border, of the same nature as the bast-cells of Exogens ;
and between the two is a stratum of cells of parenchyma mixed with
elongated and punctuated cells answering to the proper cells of the
inner part of the liber. The portion of each endogenous thread,
therefore, which looks towards the centre of the trunk, answers to
the wood, and its outer portion to the liber or inner bark, of the ex-
ogenous stem ; and the parenchyma through which the threads are
interspersed answers to the medullary rays and pith together. The
main difference between the endogenous woody threads and the ex-
ogenous woody wedges is, that there is no cambium-layer in the

THE LEAVKS. 133

former between the liber and the wood, and therefore no provision
for increase in diameter. The bundles are therefore strictly limited,
while those of Exogens are unlimited in growth. In Exogens the
woody bundles or wedges, symmetrically arranged in a circle, be-
come confluent into a zone in all woody and most herbaceous stems,
which continues to increase in thickness. In Endogens the woody
bundles are unchanged in size after their formation, but new and
distinct ones are formed in the growing stem with each leaf it de-
velops, and interspersed more or less irregularly among the older
bundles.

CHAPTER V .

OF THE LEAVES.
Sect. I. Their Arrangement. (Piiyllotaxis, etc.)

235. The situation of leaves, as well as their general office in the
vegetable economy, and several of their special adaptations, has
already been stated. Leaves invariably arise from the nodes (15G),
just below the point where buds appear. So that wherever a bud
or branch is found, a leaf exists, or has existed, either in a perfect or
rudimentary state, just beneath it ; and buds (and therefore branch-
es), on the other hand, are or may be developed in the axils of all
leaves, and do not normally exist in any other situation. The point
of attachment of a leaf (or other organ) with the stem is termed its
insertion. The subject of the arrangement of leaves on the stem has
received the name of

236. Piiyllotaxis (from two Greek words, signifying leaf-arrange-
ment).

237. As to their general position, leaves are either alternate, oppo-
site, or verticillate. They are said to be alternate (127 , and Fig.
121, 157, 204) when there is only one to each node, in which
case the successive leaves are thrown alternately to different sides
of the stem. They are said to be opposite when each node bears
a pair of leaves, in which case the two leaves always diverge
from each other as widely as possible, that is, they stand on opposite

12

134

th:: leaves.

sides of the stem and point in opposite directions (127, Fig. 107,
210, &c). They are verticillate, or whorled, when there are three or
more leaves in a circle (verticil or tohorl) upon each node ; in which
case the several leaves of the circle diverge from each other as much
as possible, or are equably distributed around the whole circumfer-
ence of the axis (Fig. 134, 211). The first of the three is the
simplest as well as the commonest method, occurring as it does in
almost every Monocotyledonous plant (where it is plainly the normal
mode, 128), and in the larger number of Dicotyledonous plants
likewise, after the first or second nodes (Fig. Ill*, 121). It
should therefore be first examined.

m 238. Alternate Leaves. This general term

for the case where leaves are placed one after
another, obviously comprises a variety of
modes as to the particular position of succes-
sive leaves. There is, first, the case to which
the name is mo-t applicable, viz. where the
leaves are alternately disposed on exactly op-
posite sides of the stem (as in Fig. 157) ; the
second leaf being on the side farthest from the
first, while the third is equally distant from
the second, and is consequently placed directly
over the first, the fourth stands over the
second, and so on throughout. Such leaves
are accordingly distichous or two-ranked.*
They form two vertical rows : on one side
are the 1st, 3d, 5th, 7th, &c. ; on the op-
posite side are the 2d, 4th, 6th, 8th, and so
on. This mode occurs in all Grasses, in many
other Monocotyledonous plants, and among
the Dicotyledonous in the Linden. A second
mode is

239. The trisdehous or three-ranked ar-
rangement, which is seen in Sedges (Fig.

* In the course of the summer the leaves of Baptisia pcrfoliata, which are
really five-ranked, often appear to be monostichous, or one-ranked ; but this is
owing to a torsion of the axis.

FIG 202. Piece of a stalk, with the sheathing bases of the leaves, of a Se<lg"-Grass (Carex
Crus-corvi), showing the three-ranked arrangement. 2C3 Diagram of the cross-sec tiou of the
same, showing two cycles of leaves.

THKIR ARRANGEMENT. 135

202) and some other Monocotyledonous plants. Taking any leaf we
please to Ijegin with, and numbering it 1, we pass round one third of
the circumference of the stem as we ascend to leaf No. 2 ; another
third of the circumference brings us to No. 3 ; another brings us
round to a point exactly over No 1, and here No. 4 is placed. No. 5
is in like manner over No. 2, and so on. They stand, therefore, in
three vertical rows, one of which contains the numbers 1, 4, 7, 10;
another, 2, 5, 8, 11 ; the third, 3, 6, 9, 12, and so on. If we draw a
line from the insertion of one leaf to that of the next, and so on to
the third, fourth, and the rest in succession, it will be perceived that
it winds around the stem spirally as it ascends. In the first or dis-
tichous mode, the second leaf is separated from the preceding by half
the circumference of the stem ; and, having completed one turn
round the stem, the third begins a second turn. In the tristiehous,
each leaf is separated from the preceding and succeeding by one
third of the circumference, there are three leaves in one turn, or
cycle, and the fourth commences a second cycle, which goes on in
the same way. That is, the angular divergence, or arc interposed
between the insertion of two successive leaves, in the first is £, in the
second ^, of the circle. These fractions severally represent, not
only the angle of divergence, but the whole plan of these two modes ;
the numerator denoting the number of times the spiral line winds
round the stem before it brings a leaf directly over the one it began
with ; while the denominator expresses the number of leaves that
are laid down in this course, or which form each cycle. The two-
ranked mode (|) is evidently the simplest possible case. The three-
ranked (£) is the next, and the one in which the spiral character of
the arrangement begins to be evident. To this succeeds

240. The pentastichous, quincuncial, or jive-ranked arrangement
(Fig. 204, 205). This is much the most common case in alternate-
leaved Dicotyledonous plants. The Apple, Cherry, and Poplar
afford ready examples of it. Here there are five leaves in each
cycle, since we must pass on to the sixth before we find one placed
vertically over the first. To reach this, the ascending spiral line has
made two revolutions round the stem, and on it the five leaves are
equably distributed, at intervals of § of the circumference. The
fraction § accordingly expresses the angular divergence of the suc-
cessive leaves ; the numerator indicates the number of turns made
in completing the cycle, and the denominator gives the number of
leaves in the cycle, or the number of vertical ranks of leaves on such

136

THE LEAVF.S.

H

a stem. If we shorten the axis, as it was in the bud, or make a
204 horizontal plan, we have su5

the parts disposed as in the
diagram, Fig. 206, the low-
er leaves being of course
the exterior.

241. The eight-ranked
arrangement, the next in
order, is likewise not un-
common. It is found in
the Holly, the Callistemon
of our conservatories, the
Aconite, the tuft of leaves
at the base of the common
Plantain, &c. In this case the ninth leaf is
placed over the first, the tenth over the second,
and so on ; and the spiral line makes three turns
in laying down the cycle of eight leaves, each
separated from the preceding by an arc, or an-
gular divergence, of $ of the circumference.

242. All these modes, or nearly all of them, m

were pointed out by Bonnet as long ago as the middle of the last
century ; but they have recently been extended and generalized, and
the mutual relations of the various methods brought to light, by
Schimper, Braun, and others. If we write down in order the series
of fractions which represent the simpler forms of phyllotaxis already
noticed, as determined by observation, viz. i, ^, f , §, we can hardly
fail to perceive the relation that they bear to each other. For the
numerator of each is composed of the sum of the numerators of the
two preceding fractions, and the denominator of the sum of the
two preceding denominators. Also the numerator of each fraction is
the denominator of the next but one preceding. Extending this
series, we obtain the further terms, T5j, ?\, ^f, -§£, &c. Now these
numbers are verified by observation, and, with some abnormal excep-
tions, this series £, \, §, f , T5;j, ?8T, £$, §-£, comprises all the varia-

FIO 204. A branch exhibiting the five-ranked arrangement of leaves

FIG 205. Diagram of the same : a spiral line is drawn ascending the stem and passing
through the successive scars which mark the position of the leaves from 1 to 6. It is made a
dotted line where it passes on the opposite side of the stem, and the scars 2 and 5, which fall
on that side, are made fainter. 206. A plane, horizontal projection of the same ; the dotted
line passing from the edge of the first leaf to the second, and soon to the fifth leaf, which
completes the cycle ; as the sixth would come directly before, or within, the first

THEIR ARRANGEMENT. 137

tions of the arrangement of alternate leaves that actually occur.
These higher forms are the most common where the leaves are
crowded on the stem, as in the rosettes of the Houseleek (Fig 207),
and the scales of the Pine-cones (for the ar-
rangement extends to all parts that are modifi-
cations of leaves), or where they are numerous
and small in proportion to the circumference of
the stem, as the leaves of Firs, &c. ' In fact,
when the internodes are long and the hase of
the leaves large in proportion to the size of the
stem, it is difficult, and often impossible, to tell
whether the 9th, 14th, or 22d leaf stands ex-
actly over the first. And when the internodes are very short, so
that the leaves touch one another, or nearly eo, we may readily per-
ceive what leaves are superposed ; hut it is then difficult to follow
the succession of the intermediate leaves. The order, however, may
be deduced by simple processes.

243. Sometimes we can readily count the number of vertical
ranks, which gives the denominator of the fraction sought. Thus, if
there are eight, we refer the case to the | arrangement in the regu-
lar series ; if there are thirteen, to the T5T arrangement, and so on.
Commonly, however, when the leaves arc crowded, the vertical ranks
are by no means so manifest as two or more orders of oblique serie-,
or secondary spirals, which are at once seen to wind round the
axis in opposite directions, as in the Houseleek (Fig. 207 ; where
the numbers, 1, 6, 11 belong to a spire that winds to the left; 1,
9, 17 to another, which winds to the right; and 3, 6, 9, 12 to still
another, that winds in the same direction) : they are still more ob-
vious in Pine-cones (Fig. 208, 209). These oblique spiral ranks
are a necessary consequence of the regular ascending arrangement
of parts with equal intervals over the circumference of the axis : and
if the leaves are numbered consecutively, these numbers will neces-
sarily stand in arithmetical progression on the oblique ranks, and
have certain obvious relations with the primary spiral which origi-
nates them ; as will be seen by projecting them on a vertical plane.

244. Take, for example, the quincunical (§) arrangement, where,
as in the annexed diagram, the ascending spiral, as written on a
plane surface, appears in the numbers 1 , 2, 3, 4, 5, G, and so on :

FIG 207. An offset of the Houseleek, with the rosette of lenves unexpanded, exhibiting th«
6-13 arrangement ; tlio fourteenth leaf being directly over the first.

12*

138

THE LKAVKS.

ascending to the left

the vertical ranks thus formed, beginning with the lowest (which
we place in the middle column, that it
may correspond with the Larch-cone, Fig.
208, where the lowest scale, 1, is turned
directly towards the observer), are neces-
sarily the numbers 1, G, ] 1 ; 4, 9, 14 ; 2, 7,
12; 5, 10, 15; and 3, 8, 13. But two
parallel oblique ranks are equally apparent,
viz. 1, 3, 5, which, if we coil the diagram
round a cylinder, will be continued into 7, 9, 11, 13, 15 , and also
2, 4, 6, 8, 10, which runs into 12, 14, and so on, if the axis be further
prolonged. Here the circumference is occupied by two secondary
left-hand series, and we notice that the common difference in the
sequence of numbers is two : that is, the number of the parallel sec-
ondary spirals is the same as the common difference of the numbers
on the leaves that compose them. Again, there are other parallel
secondary spiral ranks, three in number, which ascend to the right ;
viz. 1, 4, 7, continued into 10, 13 ; 3, G, 9, 12, continued into 15 ;
and 5, 8, 11, 14, &c. ; where again the common difference, 3, accords
Avith the number of such ranks. This fixed relation enables us to
lay down the proper numbers on the leaves, when too crowded for
directly following their succession, and thus to ascertain the order of
the primary spiral series by noticing what numbers come to be super-
posed in the vertical ranks. We take, for example, the very simple
cone of the small-fruited American Larch (Fig. 208), which usually
completes only two cycles ; for Ave see that the lowest, one interme-
diate, and the highest scale, on the side towards the observer, stand
in a vertical row. Marking this lowest scale 1, and counting the
parallel secondary spirals that Avind to the left, Ave find that two
occupy the Avhole circumference. From 1, Ave number on the scales
of that spiral 3, 5, 7, and so on, adding the common difference 2, at
each step. Again, counting from the base the right-hand secondary
spirals, Ave find three of them, and therefore proceed to number the
lowest one by adding this common difference, viz. 1,4,7, 10; then, pass-
ing to the next, on Avhich the No. 3 has already been fixed, Ave carry
on that sequence, 6, 9, &c ; and on the third, where No. 5 is already
fixed, Ave continue the numbering, 8, 11, &c. This gives us, in the
vertical rank to Avhich No. 1 belongs, the sequence 1, 6, 11, showing

FIG. 208 A rone of the small-fruited American Larch (T.arix Americana), with the scales
numbered, exhibiting tlie five-ranked arrangement, as ia the annexed diugram.

THEIR ARRANGEMENT.

139

that the arrangement is of the quineuncial (f) order. It is further
noticeable, that the smaller number of parallel secondary spirals, 2,
agrees with the numerator of the fraction in this the § arrangement ;
and that this number added to that of the parallel secondary spirals
which wind in the opposite direction, viz. 3, gives the denominator
of the fraction. This holds good throughout ; so that we have only
to count the number of parallel secondary spirals in the two direc-
tions, and assume the smaller number as the numerator, and the sum

Vertical Projection
of the -| Arrange-
ment.

Vertical Projection of the A-
Arrangement.

of this and the larger number as the denominator, of the fraction
which expresses the angular divergence sought. For this we must

FIG 209 A cone of the White Pine, on which the numbers are laid dawn, and the leading
higher secondary spirals are indicated : those with the common difference 8 aie marked by
dotted lines ascending to the right; two of the five that wind in the opposite direction are
also marked with dotted lines : the set with the common difference 3, in one direction, and
that with the common di erence 2, in the other, are very manifest ia the cone.

140 THE LKAVKS.

take, however, the order of secondary spirals nearest the vertical
rank in each direction, when there are more than two, as there are
in all the succeeding cases.

245. A similar diagram of the § arrangement introduces a set of
secondary spirals, in addition to the two foregoing, ascending in a near-
er approach to a vertical line, and with a higher common difference,
viz. 5 There are accordingly five of this sort, viz. those indicated
in the diagram by the series 1, 6, 11, 16 ; 4, 9, 14, 19, 24 ; 2, 7, 12,
17, 22 ; 5, 10, 15, 20, 25 ; and 3, 8, 13, 18, 23. The highest obvious
spiral in the opposite direction, viz. that of which- the series 1, 4, 7,
10, 13 is a specimen, has the common difference 3, and gives the
numerator, and 3 -\- 5 the denominator, of the fraction §. The next
case, T55, which is exemplified in the rosettes of the Houseleek (Fig.
207) and in the cone of the White Pine (Fig. 209), introduces a
fourth set of secondary spirals, eight in number, with the common
difference eight, viz. that of which the series 1, 9, 17, 25 is a repre-
sentative. The set that answers to this in the opposite direction,
viz. 1, 6, 11, 1G, 21, 26, with the common difference 5, gives the
numerator, and 5 -)- 8 the denominator, of the fraction -fs. We may
here compare the diagram with an actual example (Fig. 209) : a
part of the numbers are of course out of sight on the other side of
the cone. The same laws equally apply to the still higher modes.

246. The order is uniform in the same species, but often various
in allied species. Thus, it is only § in our common American Larch ;
in the European species, j8T. The White Pine is T% as is aho the
Black Spruce ; but other Pines with thicker cones exhibit in differ-
ent species the fractions ^8T, £f, and § •-. Sometimes the primitive
spiral ascends from left to right, sometimes from right to left. One
direction or the other generally prevails in each species, yet both
directions are not unfrequently met with, even in different cones of
the same tree.

247. When a branch springs from a stem or parent axis, the spi-
ral is continued from the leaves of the stem to those of the branch, so
that the leaf from whose axil the branch arises begins the spire
of that branch. When the spire of the branch turns in the same
direction as that of the parent axis, as it more commonly does, it is
said to be homodromous (from two Greek words, signifying like
course). : when it turns in the opposite direction, it is said to be
heterodromous (or of different course),

248. The cases represented by the fractions £, I, and § are the

THEIR ARRANGEMENT.

141

most stable and certain, as well as the easiest to observe. In the
higher forms, the exact order of superposition often becomes uncer-
tain, owing to a slight torsion of the axis, or to the difficulty of
observing whether the 9th, 14th, 22d, 35th, or 56th leaf is truly
over the first, or a little to the one side or the other of the vertical
line. Indeed, if we express the angle of divergence in degrees and
minutes, we perceive that the difference is so small a part of the
circumference, that a very slight change Avill substitute one order for
another. The divergence in T57 — 138° 24'. In all those beyond,
it is 137° plus a variable number of minutes, which approaches
nearer and nearer to 30'. Hence M. Bravais considers all these as
mere alterations of one typical arrangement, namely, with the angle
of divergence 137° 30' 28", which is irrational to the circumference,
that is, not capable of dividing it an exact number of times, and con-
sequently never bringing any leaf precisely in a right line over any
preceding leaf, but placing the leaves of what we take for vertical
ranks alternately on both sides of this line and very near it, approach-
ing it more and more, without ever exactly reaching it. These
forms of arrangement he therefore distinguishes as curviserial, be-
cause the leaves are thus disposed on an infinite curve, and are
never brought into exactly straight ranks. The
others are correspondingly termed rectiscrial,
because, as the divergence is an integral part
of the circumference, the leaves are necessarily
brought into rectilineal ranks for the whole
length of the stem.

249. A different series of spirals sometimes
occurs in alternate leaves, viz. \, ^, § , T3^ ; and
still others have been detected; but these are
rare or exceptional cases.

250. Opposite Leaves (237, Fig. 210). In

these, almost without exception, the second pair
is placed over the intervals of the first, the third
over the intervals of the second, and so on.
More commonly, as in plants of the Labiate
or Mint Family, the successive pairs cross each
other exactly at right angles, so that the third
pair stands directly over the first, the fourth
over the second, &c, forming four equidistant vertical ranks for the

FIG 210 Opposite leaves of the Strawberry-bush, or Euonymus Amerieanus.

142

THE LEAVES.

whole length of the stem. In this case, the leaves are said to he
decussate. In other cases, as in the Pink Family, often the succes-
sive pairs deviate a little from this line, so
that we have to pass several pairs hefore we
reach one exactly superposed over the pair
we start with. This indicates a spiral ar-
rangement, which falls into some one of the
modes already illustrated in alternate leaves*
only that here each node bears a pair of
leaves.
251. Yerticillate or Whorled Leaves (Fig. 211)

follow the same modes of arrangement as op-
Sometimes they decussate, or the leaves of one whorl
correspond to the intervals of that underneath, making twice as
many vertical ranks as there are leaves in the whorl ;
sometimes they wind spirally, so that each leaf of the
whorl belongs to as many parallel spirals, analogous
to the secondary spirals in the case of alternate
leaves.

252. The opposition or alternation of the leaves is
generally constant in the same species, and often
through the same family ; yet both modes occasionally
occur on the same stem, as in the common Snap-
dragon and the Myrtle. All Exogens, having their
cotyledons opposite, necessarily commence with that
mode (Fig. 103-125); many retain it throughout;
others change to alternation, either directly in the
primordial leaves (Fig. Ill", 121), or at a later
period. In Endogens, on the contrary, the first leaves
are necessarily alternate (128), and it is seldom that
they afterwards exhibit opposite or whorled leaves.
The Pine in germination commences with a whorl of
leaves (Fig. 133, 134) ; but the subsequent ones are
alternate. The Pine, however (Fig. 212), and the
Larch, bear what are termed 212

253. Fascicled Leaves. These are really the leaves of an axil-
lary bud. They remain in a tuft or cluster because the axis of

TIG. 211. Veiticillate or whorled loaves of a Galium or Bedstraw.

FIG 212. Piece of a branchlet of Pitch l'ine, with three leaves in a fiscicle or bundle in
the axil of a thin scale {a) which answers to a primary leaf The bundle is surrounded at the
base by a short sheath, formed of the delicate scales of the axillary bud.

VERNATION OR PRJEFOLIATION. 143

the bud does not lengthen. This is plainly seen in the spring
leaves of the Barberry and of the Larch (Fig. 213), crowded on
short spurs, some of which soon elongate into ordinary shoots with
scattered alternate leaves. Their
nature is less evident in Pines, on
account of the peculiar character of
the leaves of the main axis, from
whose axil the tuft of two, three, or
five leaves arises, the primary leaf
in this case being a thin and chaffy
scale (Fig. 212, a) which soon falls
off, while the actual foliage all be-
longs to the axillary clusters. So in the common Barberry the prop-
er leaves of the lengthened stems are chiefly in the form of spines
(Fig. 29 G), and the actual foliage appears in fascicles in their axils.
25-1. As regards their general position on the stem, leaves are said
to be radical, when they are borne on the stem at or below the sur-
face of the ground, so as apparently to grow from the root, as those
of the Bloodroot, Plantain, Primrose, and of the acaulescent (154)
Violets : those that arise along the main stem are termed cauline ;
those of the branches, rameal ; and those which stand upon or at
the base of flower-branches are called floral ; the latter, moreover,
are generally termed bracts.

255. With respect to succession, those leaves which manifestly
exist in the embryo are called seminal ; the first or original pair
receiving the name of cotyledons (120), and usually differing wide-
ly in appearance from the ordinary leaves which succeed them.
The earliest ordinary leaves are termed primordial. These, as well
as the cotyledons, usually perish soon after others are developed to
supply their place.

256. As pertaining to the arrangement of leaves, we should here
notice the modes in which they are disposed before expansion in
the bud ; namely, their

257. Vernation 01' Prafoliiltion. The latter is the most character-
istic name, but the former, given by Linnaeus (literally denoting
their spring state), is the more ancient and usual. Two things are
included under this head : — 1st, the mode in which each leaf con-
sidered separately is disposed ; 2d, the arrangement of the several

TIG 213. Piece of a brauchlet of the Larch, -with two fascicles of loaves.

144

THE LEAVES.

leaves of the same bud in respect to each other. This last is evi-
dently connected with phyllotaxis, or their position and order of
succession on the stem. As to the first, leaves are for the most
part either bent or folded, or rolled up in vernation. Thus, the
upper part may be bent on the lower, so that the apex of the leaf
is brought down towards the ba?e, as in the Tulip-tree, when the
leaves are inflexed or reclinate in vernation ; or the leaf may be
folded along its midrib or axis, so that the right half and the left
half are applied together, as in the Oak and the Magnolia, when
the leaves are conduplicate ; or each leaf may be folded up a cer-
tain number of times like a fan, as in the Maple, Currant, and Vine,
when they are said to be plicate or plaited. The leaf may be
rolled either parallel with its axis, or on its axis. In the latter case
it is spirally rolled up from the apex towards the base, like a crosier,
or circinnate, as in true Ferns (Fig. 100), and among Phamoga-
mous plants in the Drosera or Sundew. Of the former there are
three ways ; viz. the whole leaf may be laterally rolled up from one
edge into a coil, with the other edge exterior, when the leaves are
said to be convolute, as in the Apricot and Cherry ; or both edges
may be equally rolled towards the midrib ; either inwards, when
they are involute, as in the Violet and the Water-Lily ; or else out-
wards, when they are revolute, as in the Rosemary and Azalea. Fig.
214-219 are Linnaean diagrams of sections of leaves, illustrating
the principal modes of vernation.

258. Considered relatively to each other, leaves are valvate in

vernation when corresponding ones touch each other by their edges

an 2i3 2:6 only, without overlap-

>^- A f\ ^ — -^ ping: they are imbri-

//^ I *J /^T\\ cated when the outer

far ^i/LS^l J&>"\y successively overlap

the inner, by their
edges at least, in which
case the order of over-
lapping exhibits the
phyllotaxis, or order
of succession and po-
sition. In these cases
the leaves are plane or convex, or at least not much bent or rolled.

TIG. 214 Conduplicate ; 215. riieate or plaited ; 21G. Convolute ; 217
Involute ; and, 219. Circinate. vernation.

Re-olute: 218.

THEIR STRUCTURE AND CONFORMATION. 145

When leaves with their margins involute are applied together in a
circle without overlapping, the vernation is induplicate. "When, in
conduplicate leaves, the outer successively embrace or sit astride of
those next within, the vernation is equitant, as the leaves of* the Iris
at their base (Fig. 296) ; or when each receives in its fold the half
of a corresponding leaf folded in the same manner, the vernation is
half-equitant or obvolute. These terms equally apply to leaves in
their full-grown condition, whenever they are then so situated as to
overlie or embrace one another. They likewise apply to the parts
in the flower-bud, under the name of aestivation or prsefloration.
Chap. IX. Sect. V.

Sect. II. Their Structure and Conformation.

259. Anatomy of tllC Leaf. The complete leaf consists of the
Blade (Lamina or Limb, Fig. 229, b), with its Petiole or Leaf-
stalk, p, and at its base a pair of Stipules, st. Of these the latter
are frequently absent altogether, and in many cases where they
originally exist they fall away as the leaf expands. The petiole is
very often wanting ; when the leaf is sessile, or has its blade rest-
ing immediately on the stem that bears it (as in Fig. 210, 211).
Sometimes, moreover, there is no proper blade, but the whole organ
is cylindrical or stalk-like. It is the general characteristic of the leaf,
however, that it is an expanded body. Indeed, it may be viewed as
a contrivance for increasing the green surface of a plant, so as to
expose to the light and air the greatest practicable amount of paren-
chyma containing the green matter of vegetation (chlorophyll, 92),
upon which the light exerts its peculiar action. Leaves as foliage,
accordingly, are what we are now principally to consider

2 GO. In a general, mechanical way, it may be said leaves are defi-
nite protrusions of the green layer of the bark, expanded horizon-
tally into a thin lamina, and stiffened by tough, woody fibres (con-
nected both with the liber, or inner bark, and the wood), which form
its framework, ribs, or veins. Like the stem, therefore, the leaf is
made up of two distinct parts, the cellular and the woody. The
cellular portion is the green pulp or parenchyma : the woody, is the
skeleton or framework which ramifies among and strengthens the
former. The woody or fibrous portion fulfils the same purposes in
the leaf as in the stem, not only giving firmness and support to the
13

146

delicate cellular apparatus, but also serving for the conveyance and
distribution of the sap. The subdivision of these ribs, or veins, of
the leaf, as they are not inappropriately called, continues beyond
the limits of unassisted vision, until the bundles or threads of woody
tissue are reduced to very delicate fibres, ramified throughout the
green pulp.

261. The cellular portion of the leaf consists of thin-walled cells
of loose parenchyma, containing grains of chlorophyll, to which
the green color of foliage is entirely owing. The cells are not
heaped promiscuously, but exhibit a regular arrangement ; upon a
plan, too, which varies in different parts of the leaf, according to the
different conditions in which it is placed.

2G2. Leaves are almost always expanded horizontally, so as to
present one surface to the ground and the other to the sky ; and
the parenchyma forms two general strata, one belonging to the
upper and the other to the lower side. The microscope displays a
manifest difference in the parenchyma of these two strata. That
of the upper stratum is composed of one or more compact layers of
oblong cells, placed endwise, or with their long diameter perpen-
dicular to the surface ; while that of the lower stratum is very loosely
arranged, leaving numerous vacant spaces between the cells ; and
when the cells are oblong, their longer diameter is parallel with the
epidermis. This is shown in Fig. 7, which represents a magnified
section through the thickness (perpendicular to the surface) of a
leaf of the Star- Anise of Florida ; where the upper stratum of

parenchyma consists of only a
single series of perpendicular
cells. Also in Fig. 220, which
represents a similar view of a
thin slice of a leaf of the Gar-
den Balsam. Fig. 221 repre-
sents a piece cut out of a leaf
of the White Lily; where the
upper stratum is composed of
only one compact layer of ver-
tical cells. The parenchyma is alone represented ; the woody por-
tion, or veins, being left out. The more compact structure of the

FIG 220. Magnified section through the thickness of a leaf of the Garden Balsam • a, sec-
tion of the epidermis of the upper surface ; h, of the upper stratum of parenchyma J c, of the
lower stratum ; J, of the epidermis of the lower surface. (After Brongniart.)

THEIR ANATOMICAT. STRUCTURE. 147

upper stratum shows why the upper surface of leaves is of a deeper
green than the lower.

2G3. The object which this arrangement subserves will appear
evident, when we consider that the spaces between the cells, filled
with air, communicate freely with each other throughout the leaf,
and also with the external air by means of openings in the epider-
mis (presently to be described) ; and when we consider the powerful
action of the sun to promote evaporation, especially in dry air; and
that the thin walls of the cells, like all vegetable membrane, allow
of the free escape of the contained moisture by transudation. The
compactness of the cells of that stratum which is presented immedi-
ately to the sun, and their vertical elongation, so that each shall
expose 'the least possible surface, obviously serve to protect the
loose parenchyma beneath from the too powerful action of direct
sunshine. This provision is the more complete in the case of plants
which retain their foliage through a season of drought in arid re-
gions, where the soil is usually so parched during the dry season,
that, for a long period, it affords only a scanty supply of moisture to
the roots. Compare, in this respect, a leaf of the Lily (Fig. 221),
where the upper stratum contains but a single layer of barely oblong
cells, with the firm and more enduring leaf of the Oleander, the

upper stratum of which consists of two layers of long and narrow
vertical cells as closely compacted as possible (Fig. 222). So dif-

FIG. 221. A magnified section through the thickness of a minute piece of the leaf of the
White Lily of the gardens, showing also a portion of the under side with some breathing-pores.

148

THE LEAVES.

ferent is the organization of the two strata, that a leaf soon perishes
if reversed so as to expose the lower surface to direct sunshine.

264. A further and more effectual provision for restraining the
perspiration of leaves within due limits is found in the Epidermis,
or skin, that invests the leaf, as it does the whole surface of the vege-
table (69), and which is so readily detached from the succulent leaves
of such plants as the Stonecrop and the Live-for-ever (Sedum) of
the gardens. The epidermis is composed of small cells belonging to
the outermost layer of cellular tissue, with the pretty thick-sided
walls very strongly coherent, so as to form a firm membrane. Its
cells contain no chlorophyll. In ordinary herbs that allow of ready
evaporation, this membrane is made up of a single layer of cells ; as
in the Lily, Fig. 221, and the Balsam, Fig. 220. It is composed of
two layers in cases where one might prove insufficient ; and in the
Oleander, besides the provision against too copious evaporation,
already described (263), the epidermis consists of three com-
pact layers of very thick-sided
cells (Fig. 222). It is generally
thick, or hard and impermeable,
in the firm leaves of the Pitto-
sporum, Laurustinus, and other
'm plants, which will thrive, for this

very reason, where tho=;e of more delicate foliage are liable to per-
ish, in the dry atmosphere of our rooms in winter.

FIG 222. Magnified section through a part only of the thiekress of a leaf of the Oleander,
showing the epidermis of the upper surface, formed of three layers of thick-walled cells and
the two very compact layers of cylindrical cells standing endwise.

FIG. 223. Magnified slice of the epidermis and superficial parenchyma of a Cactus, after
Sehleiden ; exhibiting the epidermis (a) greatly thickened by a stratified deposition in the cells :
and some cells of the parenchyma likewise nearly filled with an incrusting deposit The depo-
sition in such cases is always irregular, leaving canals or passages which nearly connect the
adjacent cells Several of the cells contain crystals (94)

FIG 224 Similar section from another species of Cactus, passing through one of the sto-
mata, aud the deep intercellular space beneath, it.

THEIR ANATOMICAL STRUCTURE. 149

265 In such firm leaves, especially, the walls of the epidermal
cells are soon thickened by internal deposition (44), especially
on the superficial side. This is well seen in the epidermis of the
Aloe, and in other fleshy plants, which bear severe drought with
impunity : in Fig. 223, it is shown, at a, in the rind of a Cactus,
in which the green layer of the whole stem answers the purpose
of leaves. Sometimes an exterior layer of this superficial deposit
in the epidermis may be detached in the form of a continuous, ap-
parently structureless membrane, which Brongniarfc and succeeding
authors have called the Cuticle. That it may shed water readily,
the surface of leaves is commonly protected by a very thin varnish
of wax, or else with a bloom of the same substance in the form of a
whitish powder, which easily rubs off (85), as is familiarly seen in a
Cabbage-leaf.

2G6. A thickening deposit sometimes takes place in the cells of
parenchyma immediately underneath the epidermis, especially in
the Cactus Family, where the once thin and delicate walls of the
cells become excessively and irregularly thickened (Fig. 223, 224),
so as doubtless to arrest or greatly obstruct exhalation through the
rind. Something like this choking of the cells must commonly
occur with age in most leaves, particularly those that live for more
than one season (311).

267. But (he multiplication of these safeguards against exhalation
might be liable to defeat the very objects for which leaves are prin-
cipally destined. Evaporation from the parenchyma of the leaves
is essential to the plant, as it is the only method by which its exces-
sively dilute food can be concentrated. Some arrangement is requi-
site that shall allow of sufficient exhalation from the leaves while
the plant is freely supplied with moisture by the roots, but restrain
it when the supply is deficient. It is clear that the greatest demand
is made upon the leaves at the very period when the supply through
the roots is most likely to fail ; for the summer's sun, which acts so
powerfully on the leaves, at the same time parches the soil upon
which the leaves (through the rootlets) depend for the moisture they
exhale. So long as their demands are promptly answered, all goes
well. The greater the force of the sun's rays, the greater the speed
at which the vegetable machinery is driven. But whenever the
supply at the root fails, the foliage begins to flag and droop, as is so
often seen under a sultry meridian sun ; and if the exhaustion pro-
ceeds beyond a certain point, the leaves inevitably wither and perish.
13*

150

THE LEAVES.

Some adaptation is therefore needed, analogous to a self-acting valve,
which shall regulate the exhalation according to the supply. Such
an office is actually fulfilled by

2G8. The StOIliata, Stomates, or Breathing-pores (70). Through
the orifices which bear this name, exhalation principally takes place,
in all ordinary cases, Avhere the epidermis is thick and firm enough
to prevent much escape of moisture by direct transudation. The
stomata (Fig. 225-228) are always so
situated as to open directly into the hol-
low chambers, or air-cavities, which
pervade the parenchyma (Fig. 221),
especially the lower stratum, so as to
afford free communication between the
external air and the whole interior of
the leaf. The perforation of the epi-
aa dermis is between two (or rarely four)

delicate and commonly crescent-shaped cells, which, unlike the rest
of the epidermis, usually contain some chlorophyll, and in other re-
spects resemble the parenchyma beneath. "When moistened these
guardian-cells change their form, becoming more crescentic as they
become more turgid, thereby separating in the middle and opening a
free communication between the outer air and the interior of the
leaf. As they become drier, they shorten and straighten, so as to
bring the sides of the two into contact and close the orifice.* The
use of this mechanism will be readily understood. So long as the leaf

* They expand and contract most in the direction of their length ; and the
elongation and increased curvature when moist draws in the concave side and
so enlarges the aperture. The mechanism of the opening and shutting of sto-
mata has been recently investigated by Mohl (in Bot. Ze.itung for 1856, p. 697,
— an abstract of the memoir is given by C. F. Stone in Amur. Journal of Sci-
ence for March, 1857), — and these facts verified. The peculiar change of the
guardian-cells in form seems not entirely susceptible of mechanical explanation,
and is partly controlled (like other vegetable movements) by the light of the
sun ; but it mainly depends upon endosmosc. Mohl has cleaily shown that,
while the guardian-cells themselves act so as to open the stomate in moisture
and close it in dryness, the adjacent cells of the epidermis in swelling when
moist tend to close the stomate, and their contraction when dry to open it ; —
so that the actual position at any time is a resultant of nicely adjusted opposing
forces.

FIG 225 A highly magnified piece of the epidermis of the Garden Balsam, with three
Btomata (after Brongniart)

THEIR STOMATA OR BREATIIINCl-I'Oi: l S.

151

is in a moist atmosphere, and is freely supplied with sap, the sto-
mates remain open, and allow the free escape of moisture by evap-
oration. But when the supply fails, and the parenchyma begins to
be exhausted, the guardian-cells, at least equally affected by the dry-
ness, promptly collapse, and by closing these thousands of apertures
check the drain the moment it becomes injurious to the plant.

269. As a general rule, the stomata wholly or principally belong
to the epidermis of the lower

surface of the leaf: the mechan-
ism is too delicate to work well
in direct sunshine. The posi-
tion of the stomata, and the
loose texture of the lower pa-
renchyma, require that this sur-
face should be shielded from the sun's too direct and intense action ;
and show why leaves soon perish when artificially reversed, and pre-
vented from resuming (as otherwise they spontaneously will) their
natural position. This general arrangement is variously modified,
however, under peculiar circumstances. The stomata are equally
distributed on the two sides of those leaves, of whatever sort,
which grow in an erect position, or present their edges, instead of
their surfaces, to the earth and sky (294), and have the parenchyma
of both sides similarly constituted, sustaining consequently the samr
relations to light. In the Water-Lilies (Nympha?a, Nuphar), anOt
other leaves which float upon the water, the stomata all belong to
the upper surface. All leaves which live under water, where there
can be no evaporation, are destitute, not only of stomata, but usually
of a distinct epidermis also.

270. The number of the stomata varies in different leaves from
800 to about 170,000 on the square inch of surface. In the Apple,
there are said to be about 24,000 to the square inch (which is under
the average number, as given in a table of 36 species by Lindley) -,
so that each leaf of that tree Avould present about 100,000 of these
orifices. When the stomata are not all restricted to the lower sur-
face, still the greater portion usually occupy this position. Thus,
the leaf of Arum Dracontium is said to have 8,000 stomata to a
square inch of the upper surface, and twice that number in the

FIG. 226. Magnified view of the 10,000th part of a pqnnre inch of the epidermis of the
lower surface of the leaf of the White Lily, with its stomates. 227 A siuglo stomate, more
magnified. 228 Another stomate, widely open.

152 THF. LEAVES.

same space of the lower. The leaf of the Coltsfoot has 12,000
stomata to a square inch of the lower epidermis, and only 1,200 in
the upper. That of the White Lily has from 20,000 to G0,000 to
the square inch on the lower surface, and perhaps 3,000 on the up-
per. In this plant, and in other true Lilies, they are so remarkably
large (Fig. 221, 22G - 228) that they may be discerned by a simple
lens of an inch focus. In most plants they are very much smaller
than this.

271. Succulent or fleshy plants, such as those of the Cactus tribe,
Mesembryanthemums, Sedums, Aloes, &c ,are remarkable for holding
the water they imbibe with great tenacity, rather in consequence of
the thickness of the epidermis, or from the deposit which early ac-
cumulates in the superficial cells of the parenchyma (266), than
from the want of stomata. The latter are usually abundant,* but
they seem to open less than in ordinary plants, except in young and
growing parts. Hence the tissue becomes gorged as it were with
fluid, which is retained with great tenacity, especially during the
hot season. They are evidently constructed for enduring severe
droughts ; and are accordingly found to inhabit dry and sunburnt
places, such as the arid plains of Africa, — the principal home of the
Stapelias, Aloes, succulent Euphorbias, &c, — or the hottest and
driest parts of our own continent, to which the whole Cactus family
is indigenous. Or, when such plants inhabit the cooler temperate
regions, like the Sedums and the common Houseleek, &c, they are
commonly found in the most arid situations, on naked rocks, old
walls, or sandy plains, exposed to the fiercest rays of the noonday
sun, and thriving where ordinary plants would speedily perish. The
drier the atmosphere, the greater their apparent reluctance to part
with the fluid they have accumulated, and upon which they live
during the long period when little or no moisture is yielded t>y the
soil or the air Their structure and economy fully explain tneir
tolerance of the very dry air of our houses in midwinter, when or-
dinary thin-leaved plants become unhealthy or perish.

272. Sometimes the leaves of succulent plants merely become
obese or misshapen, like those of the Ice-plant and other species

* The thickener! epidermis of the fleshy leaves of the Sea-Sand wort (Hon-
kenya) is provided with an abundance of large stomata, on the upper as well
as the lower face. But this plant, though very fleshy, grows in situations where
its roots arc always supplied with moisture.

THEIR DEVELOPMENT, ETC.

153

of Mesembryanthemtim, &c. : sometimes they are reduced to tri-
angular projections or points, or are perfectly confounded with the
green bark of the stem, which fulfils their office, as in the Stapelia
and most Cacti.

273. The Development of Leaves. At their first appearance, each
leaf is a minute papilla or projection of parenchyma on the nascent
axis : as it grows, this shapes itself into the blade, and is eliminated
from the axis. The petiole, if any, is later formed, and by its
growth raises the blade from the stem. Commonly the apex of the
blade first appears, and the formation proceeds from above down-
wards. The sheath at the base (as in most Monocotyledons), or
the stipules (259, which principally belong to Dicotyledons), are at
first continuous with the blade, or divided from it by a mere con-
striction : the formation and elongation of the petiole soon separate
them. The stipules, remaining next the axis or source of nourish-
ment, undergo a rapid development early in the bud, so that, at a
certain stage, they are often larger than the body of the leaf, and
they accordingly form in such cases the teguments of the bud.
Divided or lobed and compound leaves are simple at the commence-
ment, but the lobes are very early developed , they grow in respect
to the axis of the leaf nearly as that grew from the axis of the
plant, and in the compound leaf at length isolate themselves, and
are often raised on footstalks of their own. Commonly the upper
lobes or leaflets are first formed, and then the lower : but in those
of the Walnut and Ailanthus, and other large compound leaves, the
formation proceeds from below upwards, and new leaflets continue
to be produced from the apex, even after the lowermost are nearly
full grown. In the earliest stage leaves consist of parenchyma
alone: the fibro-vascular tissue which makes the ribs, veins, or
framework appears later.

274. At the points on the surface of the developing leaf where
stomata are about to be formed, one of the epidermal cells early
ceases to enlarge and thicken with the rest, but divides into two (in
the manner formerly described, 33), forming the two guardian-cells
of the stomate : as they grow, the two constituent portions of their
common partition separate, leaving an interspace or orifice between.
In some cases, each new cell divides again, when the stomate is
formed of four cells in place of two.

275. The Forms of Leaves are almost infinitely various. These
afford some of the readiest, if not the most certain, marks for

254 THE LEAVES.

characterizing species. Their principal modifications are therefore
classified, minutely defined, and embodied in a system of nomen-
clature which is equally applicable to other parts of the plant, and
which as an instrument is indispensable to the systematic botanist.
The numerous technical terms which have gradually accumulated
from the infancy of the science, and have multiplied with its increas-
ing wants, are mostly quite arbitrary, or have been suggested by
real or fancied resemblances of their shapes to various natural or
oilier objects. Tliis arbitrary nomenclature, which formerly severe-
ly tasked the memory of the student, was reduced by De Candolle
to a clear and consistent system, based upon scientific pr.nciples,
and of easy application. The fundamental idea of the plan is, that
the almost infinite varieties in the form and outline of leaves may
be deduced from the different modes and degrees in which the
woody skeleton or framework of the leaf is expanded or ramified
in the parenchyma. Upon this conception the following sketch is
based ; in which all the more important terms of the nomenclature
of leaves are mentioned and defined. It should be kept in mind,
however, that this is not to be taken as an explanation of the actual
formation of leaves ; but rather as an account of the mutual adap-
tation and correspondence of their outlines and framework. For
the parenchyma is developed, and the form of the leaf more or less
determined, before the framework has an existence. The latter,
therefore, cannot have given rise to the outline or shape of the
organ. The distribution of the veins or fibrous framework of the
leaf in the blade is termed its

27G. Venation. The veins are distributed throughout the lamina
in two principal modes. Either the vessels of the petiole divide at
once, where they enter the blade, into several veins, which run
parallel with each other to the apex, connected only by simple
transverse veinlets (as in Fig. 230) ; or the petiole is continued
into the blade in the form of one or more principal or coarser
veins, which send off branches on both sides, the smaller branch-
lets uniting with one another [anastomosing) and forming a kind
of network ; as in Fig. 229. The former are termed parallel-
veined, or commonly nerved leaves ; the veins in this case having
been called nerves by the older botanists, — a name which it is
found convenient to retain, although of course they are in no respect
analogous to the nerves of animals. The latter are termed reticu-
lated or netted-veined leaves.

THEIR VENATION.

155

277. Parallel-veined or nerved leaves are characteristic of En-
dogenous plants ; while reticulated leaves are almost universal in

Exogenous plants. We are thus furnished with a very obvious, al-
though by no means absolute, distinction between these two great
classes of plants, independently of the structure of their stems (198).
278. In reticulated leaves, the coarse primary veins (one or
more in number), which proceed immediately from the apex of the
petiole, are called ribs ; the branches are termed veins, and their
subordinate ramifications, veinlets. Very frequently, a single strong
rib (called the midrib), forming a continuation of the petiole, runs
directly through the middle of the blade to the apex (Fig. 229, 238,
&c), and from it the lateral veins all diverge. Such leaves are
termed feather-veined or pinnately veined; and are subject to vari-
ous modifications, according to the arrangement of the veins and vein-
lets ; the primary veins sometimes passing straight from the midrib
to the margin, as in the Beech and Chestnut (Fig. 238) ; while
in other cases they are divided into veinlets long before they reach
the margin. When the midrib gives off a very strong primary vein
or branch on each side above the base, the leaf is said to be triple-
ribbed, or often tripli-nerved, as in the common Sunflower (Fig.

FIG. 229 A leaf of the Q
p, petiole or leaf-stalk : st, stipules.

I'lG 230. Parallel- veined leaf of the Lily of the Valley

of the netted-veined or reticulated sort : b, blade :

156

THE LEAVES.

2 41) ; if two such ribs proceed from each side of the midrib, it is
said to be quintuple-ribbed, or quintupli-nerved.

231 232

279. Not unfrequently the vessels of a reticulated leaf divide at
the apex of the petiole into three or more portions or ribs of nearly-
equal size, which are usually divergent, each giving off veins and
veinlets, like the single rib of a feather-veined leaf. Such leaves
are termed radiated-veined, or palmately-veined ; and, as to the
number of the ribs, are called tln-ee-ribbed, five-ribbed, seven-ribbed,
&c. (Fig. 244, 247, 253). Examples of this form are furnished by
the Maple, the Gooseberry, the Mallow family, &c. Occasionally
the ribs of a radiated-veined leaf converge and run to the apex of the
blade, as in Ehexia and other plants of the same family, thus resem-
bling a parallel-veined or nerved leaf; from which, however, it is
distinguished by the intermediate netted veins. But when the ribs
are not very strong, such leaves are frequently said to be nerved,
although they branch before reaching the apex.

280. According to the theory of De Candolle (275), the shape
which leaves assume may be viewed as dependent upon the dis-
tribution of the veins, and the quantity of parenchyma; the gen-
eral outline being determined by the division and direction of the
veins ; and the form of the margin, (whether even and continuous,
or else interrupted by void spaces or indentations,) by the greater or

FIG 231-244 Various forms of simple leaves.

TIIKTR FOmrS.

1.37

¥less abundance of the parenchyma in which (he veins are distrib-
uted. This view is readily intelligible upon the supposition that a

245 147 2)8

leaf is an expansion of soft parenchyma, in which the firmer veins
are variously ramified. Thus, if the principal veins of a feather-
veined leaf are not greatly prolonged, and are somewhat equal in
length, the blade will have a more or less elongated form. If the
veins are very short in proportion to the midrib, and equal in length,
the leaf will be linear (as in Fig. 240) ; if longer in proportion,
but still equal, the leaf will assume an oblong form (Fig. 242),
which a slight rounding of the sides converts into an oval or ellip-
tical outline. If the veins next the base are longest, and especially
if they curve forward towards their extremities, the leaf assumes a
lanceolate (Fig. 239), ovate (Fig. 241), or some intermediate form.
On the other hand, if the veins are more developed beyond the mid-
dle of the blade, the leaf becomes obovate (Fig. 232), or cuneiform
(Fig. 235). In radiated or palmately veined leaves (Fig. 245-253),
where the primary ribs are divergent, an orbicular or roundish out-
line is most common. When some of the ribs or their ramifications
are directed backwards, a recess, or sinus, as it is termed, is pro-
duced at the base of the leaf, which, taken in connection with the
general form, gives rise to such terms as cordate or heart-shaped
(Fig. 244), reniform or kidney-shaped (Fig. 245), &c, when the
posterior portions are rounded ; and those of sagittate or arrow-
headed (Fig. 252), and hastate or halberd-shaped (Fig. 250), when

FIG 245-253. Forms of simple, chiefly radiated-veined leaves.

14

158 th;: leaves.

the angles or lobes at the base diverge. The margins of the sinus
are sometimes brought into contact and united, when the leaf be-
comes peltate or shield-shaped (Fig. 24S) ; the blade being attached
to the petiole, not by its apparent base, but by some part of the
lower surface. Two or three common species of Hydrocotyle
plainly exhibit the transition from common radiated leaves into the
peltate form. Thus, the leaf of H. Americana (Fig. 247) is round-
ish-reniform, with an open sinus at the base, while in II. inter-
rupta and Ii. umhellata (Fig. 248), the margins have grown to-
gether so as to obliterate the sinus, and an orbicular peltate leaf is
produced. In nerved leaves, when the nerves run parallel from
the base to the apex, as in Grasses (Fig. 237), the leaf is necessa-
rily linear, or nearly so ; but when they are more divergent in the
middle, or towards the base, the leaf becomes oblong, oval, or ovate,
&c. (Fig. 243). In one class of nerved or parallel-veined leaves, the
simple veins or nerves arise from a prolongation of the petiole in the
form of a thickened midrib, instead of the base of the blade, constitut-
ing the curvinerved leaves of De Candolle. This structure is almost
universal in the Ginger tribe, the Arrowroot tribe, in the Banana, and
other tropical plants ; and our common Pontederia, or Pickerel-weed
(Fig. 236), affords an illustration of it, in which the nerves are
curved backwards at the base, so as to produce a cordate outline.

281. As to the margin and particular outline of leaves, they ex-
hibit every gradation between the case where the blade is entire,
that is, with the margin perfectly continuous and even (as in Fig.
243), and those where it is cleft or divided into separate portions.
The convenient hypothesis of De Candolle connects these forms
with the abundance or scantiness of the parenchyma, compared
with the divergence and the extent of the ribs or veins ; on the
supposition that, where the former is insufficient completely to fill
up the framework, lobes, incisions, or toothings are necessarily
produced, extending from the margin towards the centre. Thus,
in the white and the yellow species of Water Ranunculus, there
appears to be barely sufficient parenchyma to form a thin covering
for each vein and its branches (Fig. 251, the lowest leaf) ; such
leaves are said to be jiliformhj dissected, that is, cut into threads ;
the nomenclature in all these cases being founded on the conven-
ient (but incorrect) supposition, that a leaf originally entire is cut
into teeth, lobes, divisions, &c. If, while the framework remains
the same as in the last instance, the parenchyma be more abun-

THEIR FORMS.

159

danlly developed, as in fact happens in the upper leaves of the same
species when they grow out of water, and is shown in the same
figure, they are merely cleft or lobed. If these lobes grow together
nearly to the ex-
tremity of the /vl/X\ FT'
principal veins, rJ ^pia-V
the leaf is only [ V^J
toothed, serrated, J y
or crenated; and
if the small re-
maining notches
were filled with
parenchyma, the
leaf would be en-
tire. The study

of the development of leaves, however, proves that the parenchyma
grows and shapes the outlines of the organ in its own way, irrespec-
tive of the framework, which is, in fact, adapted to the parenchyma
rather than the parenchyma to it. The principal terms which designate
the mode and degree of division in simple leaves may now be briefly
explained, without further reference to this or any other theory.

282. A leaf is said to be serrate, when the margin is beset with
sharp teeth which point forwards towards the apex (Fig. 254) ;
dentate, or toothed, when the sharp salient teeth are not directed
towards the apex of the leaf (Fig. 255); and crenate, when the
teeth are rounded (Fig. 248, 256). A slightly waved or sinuous
margin is said to be repand (Fig. 257) ; a more strongly uneven
margin, with alternate rounded concavities and convexities, is termed
sinuate (Fig. 258). When the leaf is irregularly and sharply cut
deep into the blade, it is said to be incised (Fig. 259) ; when the
portions (or segments) are more definite, it is said to be lobed (Fig.
260, 264) ; and the terms two-lobed, three-lobed (Fig. 264), fve-lobed,
&c, express the number of the segments. If the incisions extend about
to the middle of the blade, or somewhat deeper, and especially if the
sinuses are acute, the leaf is said to be cleft (Fig. 261, 265) ; and
the terms two-cleft, three-cleft (Fig. 265), &c. (or in the Latin form,
bifid, trifid, &c), designate the number of the segments : or when
the latter are numerous or indefinite, the leaf is termed many-cleft,
or multifid. If the segments extend nearly, but not quite, to the

FIG 254 - 259 Forms of leaves as to the toothing of their margins.

1G0

THE LF.AVICS.

ba*e of the blade or the midrib, the leaf Is ^aid to be parted (Fig.
262, 2G6) : if they reach the midrib or the base, so as to interrupt

the parenchyma, the leaf is said to be divided (Fig. 263, 267) ; the
number of partitions or divisions being designated, as before, by the
terms two-, three-, jive-parted, or two-, three-, jive-divided, &c.

283. As the mode of division always coincides with the arrange-
ment of the primary veins, the lobes or incisions of feather-veined,
are differently arranged from those of radiated or palmately veined
leaves : in the latter, the principal incisions are all directed to the
ba>e of the leaf; in the former, towards the midrib. These modi-
fications are accurately described by terms indicative of the vena-
tion, combined with those that express the degree of division.
Thus, a feather-viened (in the Latin form, a pinnately veined) leaf
ii said to be pinnately clejt or pinnatijid (Fig. 261), when the
sinuses reach half-way to the midrib ; pinnately parted, when they
extend almost to the midrib (Fig. 262) ; and pinnately divided,
when they reach the midrib, dividing the parenchyma into separate
portions (Fig. 263). A few subordinate modifications are in-
dicated by special terms : thus, a pinnatifid or pinnately parted
leaf, with regular, very clo;;e and narrow divisions, like the teeth of
a comb, is said to be pectinate ; a feather-veined leaf, more or less
pinnatifid, but with the lobes decreasing in size towards the base, is

FIG 260 - 2GT Pinnately and palmately lobed, cleft, parted, and divided leaves.

TIIKIR FORMS. 161

termed lyrate, or lyre-shaped (Fig. 278) ; and a Iyratc leaf with
sharp lobes pointing towards the base, as in the Dandelion (Fig.
279), is called runcinate. A palmately veined leaf is in like man-
ner said to he palmately lobed (Fig. 2G4), palmately cleft (Fig. 265),
palmately parted (Fig. 2G6), or palmately divided (Fig. 267), ac-
cording to the degree of division. The term palmate was originally
employed to designate a leaf more or less deeply cut into about five
spreading lobes, bearing some resemblance to a hand with the fingers
spreading ; and it is still used to designate a palmately lobed leaf,
without reference to the depth of the sinuses. A palmate leaf with
the lateral lobes cleft into two or more segments is said to be pedate
(Fig. 249), from a fancied resemblance to a bird's foot. By desig-
nating the number of the lobes in connection with the terms which
indicate their extent and their disposition, botanists are enabled to
describe all the~e modifications Avith great brevity and precision.
Thus, upalmately three-parted leaf is one of the radiated-veined kind,
which is divided almost to the, base into three segments (Fig. 266) ;
a pinnately jive-parted leaf is one of the feather-veined kind cut into
five lobes (two on each side, and one terminal), with the sinuses ex-
tending almost to the midrib : and the same plan is followed in de-
scribing cleft, lobed, or divided leaves.

284. The segments of a lobed or divided leaf may be again di-
vided, lobed, or cleft, in the same way as the original blade, and the
same terms are employed in describing them. Sometimes both the
primary, secondary, and even tertiary divisions are defined by a
single word or phrase ; as bipiiuiatijid (Fig. 280), tripinnatijid,
hip innately parted, tripinnately parted, twice palmately parted, &c.

285. Parallel-veined or nerved leaves would naturally be ex-
pected to present entire margins, and this they almost universally
do when the nerves are convergent (Fig. 230, 243). Such leaves
are often lobed or cleft when the principal nerves diverge greatly,
as in the Dragon Arum ; but the lobes themselves are entire.

286. There are a few terms employed in describing the apex of
a leaf, which may be here enumerated. When a leaf tapers to a

FIG 2R8-276 Forms of the apex of leaves.
14*

162

THE LKAVES.

narrowed or slender apex, it is said to be acuminate (Fig. 26S) :
when it terminates in an acute angle, it is said to be acute (Fig.
2 GO) : when the apex is an obtuse angle, or rounded, it is termed
obtuse (Fig. 270) : an obtuse leaf, with the apex slightly indented or
depressed in the middle, is said to be retuse (Fig. 272), or, it* more
strongly notched, emarginate (Fig. 273): an obovate leaf with a
wider and more conspicuous notch at the apex is termed obcordate
(Fig. 274), being a cordate or heart-shaped leaf inverted. When
the apex i<, as it were, cut off by a straight transverse line, the leaf
is said to be truncate (Fig. 271) : when abruptly terminated by a
small and slender projecting point, it is mucronate (Fig. 276) : when
tipped with a stronger and rigid projecting point, or cusp, it is cuspi-
date (Fig. 275).

287. All these terms are equally applicable to expanded sur-
faces of every kind, such as petals, sepals, &c. : and those terms
which are used to describe the modifications of solid bodies, such as
stems and stalks, arc equally applicable to leaves when these affect
similar shapes, as they sometimes do.

288. The whole account, thus far, relates to Simple Leaves,
namely, to tho.-.e which have a blade of one piece, however cleft or
lobed, or, if divided, where the separate portions are neither raised on

285 288

FIG 277 -287. Various forms of lobed and compound leaves.

COMPOUND LEAVES.

stalklets of their own, nor articulated (by a joint) with the main
petiole, so that the pieces are at length detached and fall separately.
The distinction, however, cannot be very strictly maintained ; there
are so many transitions between simple and

289. Compound Leaves. These have the blade divided into entire-
ly separate pieces ; or, rather, they consist of a number of blades,
borne on a common petiole, usually supported on sialklets of their
own, between which and the main petiole an articulation or joint is
formed, more or less distinctly. These separate blades are called
Leaflets : they present all the diversities of form, outline, or
division which simple leaves exhibit ; and the same terms are em-
ployed in characterizing them. Having the same nature and origin
as the lobes or segments of simple leaves, they are arranged in the
same ways on the common petiole. Compound leaves accordingly
occur under two general forms, the pinnate and the palmate (other-
wise called digitate).

290. The pinnate form is produced when a leaf of the pinnately
veined sort becomes compound ; that is, the leaflets are situated
along the sides of the common petiole. There are several modifica-
tions of the pinnate leaf. It is abruptly pinnate, when the leaflets
are even in number, and none is borne on the very apex of the
petiole or its branches, as in Cassia (Fig. 290), and also in the
Vetch tribe, where, however, the apex of the petiole is generally

prolonged into a tendril (Fig. 287, 289). It is impari-pinnate, or
pinnate with an odd leaflet, when the petiole is terminated with a

FIG. 288 - 290. Simply pinnate leaves of yurious forms.

1G4 THE LEAVES.

leaflet (Fig. 281, 288). There are some subordinate modifications;
such as lyrately pinnate, when the blade of a lyrate leaf (Fig. 278)
is completely divided, as in Fig. 285 ; and interruptedly pinnate,
when some minute leaflets are irregularly intermixed with larger
ones, as is also shown to some extent in the figure last cited. The
number of leaflets varies from a great number to veiy few. When
reduced to a small number, such a leaf is said to be pinnately seven-,
or five-, or tri-foliolate, as the case may be. A pinnate leaf of three
or five leaflets is often called ternate or quinate ; which term-, how-
ever, are equally applied to a palmately compound leaf, and also,
and more appropriately, to the case of three or five simple leaves
growing on the same node. A pinnately trifoliolate leaf (Fig. 28 G)
is readily distinguished by having the two lateral leaflets attached
to the petiole at some distance below its apex, and by the joint
which is observable at some point between their insertion and the
lamina of the terminal leaflet. Such a leaf may even be reduced
to a single leaflet ; as in the Orange (Fig. 283) and the primordial
leaves of the common Barberry. This is distinguished from a
really simple leaf by the joint at the junction of the partial with the
general petiole.

291. The palmate or digitate form is produced when a leaf of the
palmately veined sort becomes compound ; in which case the leaflets
are necessarily all attached to the apex of the common petiole, as in
the Horsechestnut and Buckeye (Fig. 277), and the common Clover
(Fig. 304). Such leaves of three, five, or any definite number of
leaflets, are termed palmately (or digitately) trifoliolate, Jive-foliolate,
&c. A leaf of two leaflets, which rarely occurs, is unijugate (one-
paired) or binate. By this nomenclature, the distinction between
pinnately and palmately compound leaves is readily kept up, and
every important character of a leaf is expressed with brevity and
accuracy.

292. The stalk of a leaflet is called a partial petiole (petiolide) ;
and the leaflet thus supported is petiolulate. The partial petioles
may bear a set of leaflets, instead of a single one, when the leaf
becomes doubly or twice compound. Thus a pinnate leaf again com-
pounded in the same way becomes bipinnate (Fig. 282), or if still
a third time divided it is tripinnate, &c. In these cases the main
divisions or branches of the common petiole are called pinnce, or the
pairs jugce. So a trifoliolate leaf twice compound becomes biternate
(Fig. 284) ; or thrice, tritemate, &c. "When the primary division

VERTICAL AND PERFOLIATE: LEAVES.

165

is digitate, the secondary division is often pinnate, thus combining
the two modes in the same leaf. A leaf irregularly or indeter-
minately several times compounded, in whatever mode, is said to be
decompound.

293. Leaves of Peculiar Conformation. The blade of a leaf is almost

always symmetrical, that is, the portions on each side of the midrib
or axis are similar ; but occasionally one side is more developed than
the other, when the leaf is oblique, as is strikingly the case in the
species of Begonia (Fig. 246) of our conservatories.

294. Vertical and Equitant Leaves. The blade is also

commonly horizontal, presenting one surface to the
sky, and the other to the earth ; in which case the
two surfaces differ in structure (262) as Avell as in
appearance, each being fitted for its peculiar of-
fices : if artificially reversed, they spontaneously
resume their natural position, or soon perish if
prevented from doing so. But in erect and verti-
cal leaves, the two surfaces are equally exposed
to the light, and are similar in structure and ap-
pearance. In such erect and equitant leaves as
those of Iris (Fig. 291), it is really the lower sur-
face that is presented to the air ; for the leaf is
folded together lengthwise
(conduplicate), and consoli-
dated while in the nascent
state, so that the true upper
surface is concealed in the
interior, except near the
base, where they alternately
cover over each other in the
equitant manner (258, Fig.
292). True vertical leaves,
which present their edges instead of their surfaces to the earth and
sky, generally assume this position by a twisting of the base or
the petiole ; as is strikingly seen in the Callistemon and many other
Australian trees of the Myrtle family, some of which are now com-
mon in green-houses.

295. Perfoliate Leaves. While in Iris the two halves of the

FIG 291. Equitant erect leaves of Iris, with the rootstock.

FIG £92. A section across these leaves at the base, showing their etputant character.

106

TIIK I,KAVKS,

upper surface of a folded leaf cohere, those of some other plants ex-
hibit a cohesion by their contiguous edges, and give rise to a differ-
ent anomaly. This is illustrated by peltate
leaves (Fig. 248), and more strikingly by
what are termed perfoliate leaves. These in
some cases originate from the union of the
bases of a pair of opposite sessile leaves (con-
nate-perfoliate), as in Silphium perfoliatum,
Triosteum perfo-
liatum, and the
upper pairs of
true Honeysuckle
(Fig. 294). In
others they con-
sist of a single
clasping leaf, the
posterior lobes of
which encompass the stem and cohere
on the opposite side, as is seen in Bu-
pleurum rotundifolium, Uvularia perfo-
rata, and Baptisia perfoliata (Fig. 293).

296. Leaves with no distinction of Blade

and Petiole. The leaves of the Iris, as
well as those of the Daffodil, the Onion,
and of many other Endogens, show no
distinction of blade and petiole. In some the leaf of this sort may
be regarded as a sessile blade ; in others, rather as a petiole per-
forming the functions of a blade. Leaves are not always expanded
bodies. Sometimes they are filiform or thread-shaped, as tho^e of
Asparagus : some are acicidar, acerose, or needle-shaped, as in Pines
and Larches (Fig. 212, 213) ; others are subulate or aid-shaped, as
in Juniper, &c. The Red Cedar and Arbor Vitas (Fig. 295) exhibit
both awl-shaped and scale-shaped leaves on different branchlets. -

297. Succulent Of Fleshy Leaves, like tho.-e of Stonecrop, House-
leek, Mesembryanthemum or Ice-Plant, and the Agave or Century-
Plant, usually assume shapes more or less unlike ordinary foliage.
Some of them are terete, like stems, or at least have no distinct
upper and lower surface. These greatly thickened leaves serve a

FIG 293. Perfoliate (single) leaves of Baptisia perfoliata.

JIG. 294. Connate-perfoliate leaves of a wild Honeysuckle (Lomcera fiava).

AS BUD-SCALES, TENDKILS, SPIKES, KTC.

1C7

double purpose, being not only organs for assimilation, — the general
office of foliage, — but also repositories in which
assimilated matter is stored up, just as in the root
of the Beet and Radish (Fig. 138), or in subter-
ranean stems or branches in rootstocks, tubers,
and corms ( 188 - 190, 194). The bases of those
leaves which form the scales of bulbs (191) are
turned to the same use. In Fig. 176 we have a
leaf the blade of which acts as foliage in the ordi-
nary manner of leaves, while its subterranean
thickened base serves as a repository of nutri-
ment which the blade has elaborated. The very
first leaves of the plant, viz. the cotyledons or
seed-leaves (120-123) are commonly subservi-
ent to this purpose, and some-
.i/L__ times to no other, as in the

Pea, Horsechestnut, Oak, &c.
(124), where these leaves are mere repositories
of food for the use of the germinating plant.

298. Leaves as Bud-scales, &c. (161) exhibit the

same organ under a different modification, and
subserving a different special purpose. Of the
same nature are the degenerated or abortive
y^Hni scale-like leaves on the vernal stems of peren-

/ ' 1 nial herbs near or beneath the surface of the

ground, and on Asparagus shoots, and also those
scales which colored parasitic plants produce in
place of foliage (1;32). The primary leaves of
Pines are all thin and dry bud-scales ; the actual
foliage originating from a branch in the axil of
each (Fig. 212).

299. Leaves as Tendrils are seen in the proper
Pea tribe ; where however only the extremity
of the common petiole is transformed in this

295 manner (Fig. 287, 289) ; but in one plant

of the kind (Lathyrus Aphaca) the whole leaf becomes a tendril.
300. Leaves as SpillCS occur in several plants. The primary leaves

PIG. 295. A twig of American Arbor Vitu?, exhibiting both awl-shaped and scale-shaped
leaves

FIG 296. A summer shoot of the Barberry, showing a lower leaf in the normal state ; the
Bext partially, those still higher completely, transformed into spines.

108

TIIK T.KAVKS,

of the shoots of (he common Barberry offer a familiar instance of
the kind (Fig. 29G). The most extraordinary modification of the
leaf occurs in the

301. Fly-traps of Dionsea muscipula, the Venus's Fly-trap of North

Carolina (which is found only
in the vicinity of "Wilming-
ton, where it abounds in
/vf%^ wet and sandy bogs). Each

leaf of this most curious plant bears at its summit an append-
age (answering, perhaps, to the proper blade), which opens and
shuts : fringed with strong bristles or slender teeth on its margin,
it bears some resemblance to a steel-trap, and operates much like
one. For when open, as it commonly is when the sun shines,
no sooner does a fly alight on its surface, and brush against any
one of the several long bristles that grow there, than the trap
suddeidy closes, often capturing the intruder, pressing it all the
harder for its struggles, and commonly depriving it of life. After
all movement has ceased within, the trap slowly opens, and is ready
for another capture. Why this plant catches insects, we are unable
to say ; and as to the mechanism of the movement it is no more and
no less explicable than the much slower movements of ordinary
leaves in changing their position.

FIG 297 A plant of Pionaca muscipula, reduced in si;
nearly the natural size ; one of them open, the others closed.

2DS Three of the leaves, of

AS ASCIDIA OR PITCHKRS.

1G9

302. Ascidia or Titchers, or tubes open at the summit, represent
another remarkable form of leaves. These occur in several plants
of widely different families. If we conceive the margins of the
dilated part of the leaf of Dionaja to curve inwards until they meet,
and cohere with each other, there would result a leaf in form not
unlike that of Sarracenia purpurea, the common Pitcher-plant or
Sidesaddle Flower of the Northern United States (Fig. 300). So

the tube or pitcher has been supposed to answer to the petiole, and
the hood at the summit to the blade. And this view is strengthened
by a Pitcher-plant of the same family (Heliamphora, Fig. 299),
discovered by Mr. Schomburgk in the mountains of British Guiana,
in which the pitcher is not always completed quite to the summit,
and the hood is represented by a small concave terminal appendage.
In the curious Nepenthes (Fig. 301), the petiole is first dilated into
a kind of lamina, then contracted into a tendril, and finally dilated
into a pitcher, containing fluid secreted by the plant itself; the orifice
being accurately closed by a lid, which from analogy was supposed to
represent the real blade of the leaf. The study of the development,
however (recently made by Dr. Hooker), does not confirm this
hypothesis. The whole pitcher of Nepenthes is only an anom-
alous appendage of the tendril-like prolongation of the midrib of the
real blade of the leaf. A new Pitcher-plant of the Sarracenia family
(the Darling! onla), discovered by Mr. Brackenridge in California,

FIG. 299 Pitchers of Heliamphora; 300, of Sarracenia purpurea; 301, of Nepenthes.
302. A phyllodiuin of a New Holland Acacia. 303. The same, bearing a reduced compouud
blade.

15

170 THK LEAVES.

has recently been made known by Dr. Tprrey. In this the enlarged
summit of the tube is strongly arched like a hood (as in Sarracenia
psittacina of the Southern States), and is .abruptly terminated by a
singular two-lobed foliaceous appendage, resembling the forked tail
of a fish.

303. The Petiole, or Leafstalk, is usually either round, or half-cylin-
drical and channelled on the upper side. But in the Aspen, it is
strongly flattened at right angles with the blade, so that the slightest
breath of air puts the leaves in motion. It is not unfrequently fur'
nished with a leaf-like border, or ring ; which, in the Sweet Pea of
the gardens, extends downward along the stem, on which the leaves
are then said to be decurrent ; or the stalk or stem thus bordered
is said to be alate or winged. In many Umbelliferous plants, the
petiole is dilated below into a broad and membranaceous inflated
sheath ; and in a great number of Endogenous plants the petiole
consists of a sheath, embracing the stem, which in Grasses is fur-
nished at the summit with a membranous appendage, in some sort
equivalent to the stipules, called the ligule (Fig. 237). The woody
and vascular tissue runs lengthwise through the petiole, in the form
usually of a definite number of parallel threads, to be ramified in the
blade. The ends of these threads are apparent on the base of the
leafstalk when it falls off, and on the scar left on the stem, as so
many round dots (Fig. 153, b), of a uniform number and arrange-
ment in each species.

304. Phyllodia (Fig. 302, 303). Occasionally the whole petiole
dilates into a kind of blade, traversed by ribs, mostly of the parallel-
veined kind. In these cases the proper blade of the leaf commonly
disappears ; this substitute, called a Phyllodium (meaning a leaf-like
body), taking its place. These phyllodia constitute the whole foliage
of the numerous Australian Acacias. Here they are at once dis-
tinguished from leaves with a true blade by being entire and parallel-
veined ; while their proper leaves (of which the earlier ones uni-
formly appear in germination, and also later ones in casual instances)
are compound and netted-veined. They are also to be reepgnized by
their uniformly vertical position, presenting their margins instead of
their surfaces to the earth and sky ; and they sometimes bear a true
compound lamina at the apex, as in Fig. 303.

305. Stipules (259, Fig. 229) are lateral appendages of leaves,
usually appearing as small foliaceous bodies, one on each side of the
base of the petiole. They are not found at all in a great number of

STIPULES.

171

plants ; but their presence or absence is usually uniform throughout
a natural order. Stipules assume a great variety of forms analogous
to those of the blade. Like it they are sometimes membranaceous
or scale-like, and sometimes transformed into spines, as in the Locust-
tree, &c. They are sometimes present on developing shoots
only; as in the Beech, the Fig, and the Magnolia (Fig. 155, 15G),
where they form the covering of the buds, but fall away as the
leaves expand. They have a strong
tendency to cohere with each other, or
with the base of the petiole. Thus, in
the Clover (Fig. 304), the Strawberry,
and the Rose (Fig. 281), a stipule ad-
heres to each side of the base of the
petiole ; in the Plane-tree, the two are
free from the petiole, but cohere by
their outer margins, so as to form an
apparently single stipule opposite the
leaf. In other cases, both margins ; re
united, forming a sheath around the
stem, just above the leaf: these are
called intrafoliaceous stipules ; and
when membranaceous, as in Polygo-
num (Fig. 305), they have been termed
ochrece. When opposite leaves have
stipules, they usually occupy the space
between the petioles on each side, and
are termed interpetiolar. The stipules
of each leaf (one on each side), being
thus placed in contact, frequently unite 304 303

so as to form apparently but a single pair of stipules for each pair
of leaves ; instances of which are very common in the order
Pvubiaceas.

306. Leaves furnished with stipules are said to be stipulate : when
destitute of them, exstipulate. The leaflets of compound leaves are
sometimes provided with small stipules (termed stipelles) of their
own, as in the Bean (Fig. 286) ; when they are said to be stipellate.

FIG 304. A leaf of Red Clover, with its three leaflets at the summit of the leafstalk, to
which at the base the stipules (st) are adherent, one on each side.

FIG. 305. Part of a lenf of Polygonum orientale, with iU stipules united into a Bueath
(ochrea) and surrounding the stem.

172 Tilt: LEAVES.

Skct. III. The Duration ok Leaves, and the General
Action of Foliage.

307. Leaves last only for a limited period, and are thrown off,
or else perish and decay on the stem, after having fulfilled their
office for a certain time.

308. Duration of Leaves. In view of their duration, leaves are
called fugacious, when they fall off soon after their appearance ;
deciduous, when they last only for a single season ; and persist-
ent, when they remain through the cold season, or other interval
during which vegetation is interrupted, and until after the appear-
ance of new leaves, so that the stem is never leafless ; as in Ever-
greens.

309. Leaves last only for a single year in many Evergreens, as
well as in deciduous-leaved plants ; the old leaves falling soon after
those of the ensuing season are expanded, or, if they remain longer,
ceasing to bear any active part in the economy of the vegetable,
and soon losing their vitality altogether. In Pines and Firs, how-
ever, although there is an annual fall of leaves either in autumn or
spring, yet these were the produce of some season earlier than the
last ; and the branches are continually clothed with the foliage of
from two to five, or even eight or ten, successive years. On the
other hand, it is seldom that all the leaves of an herb endure
through the whole growing season, the earlier foliage near the base
of the stem perishing while fresh leaves are still appearing above.
In our deciduous trees and shrubs, however, the leaves of the
season are mostly developed within a short period, and they all
perish nearly at the same time. They are not destroyed by frost,
as is commonly supposed ; for they begin to languish, and often
assume their autumnal tints (as happens with the Red Maple
especially), or even fall, before the earlier frosts ; and when vernal
vegetation is destroyed by frost, the leaves blacken and wither, but
do not fall off 'entire, as they do in autumn. Some leaves are cast
off, indeed, while their tissues have by no means lost their vital-
ity. Death is often rather a consequence than the cause of the
fall. Others die and decay on the stem without falling, as in
Palms and most Ehidogens. In some cases many of the dead
leaves hang on the branches through the winter, as in the Beech,
falling only when the new buds expand, the following spring. We

THEIR DEATH AXD FALL. 173

must therefore distinguish between the death and the fall of the
leaf.

310. The Fall of the Leaf is owing to an organic separation, through
an articulation, or joint, which forms between the base of the
petiole and the surface of the stem on which it rests. The forma-
tion of the articulation is a vital process, a kind of disintegration of
a transverse layer of cells, which cuts off the petiole by a regular
line, in a perfectly uniform manner in each species, leaving a clean
scar at the insertion (Fig. 153, 155). The solution of continuity
begins in the epidermis, where a faint line marks the position of the
future joint while the leaf is still young and vigorous : later, the
line of demarcation becomes well marked, internally as well as ex-
ternally ; the disintegrating process advances from without inwards
until it reaches the woody bundles ; and the side next the stem,
which is to form the surface of the scar, has a layer of cells con-
densed into what appears like a prolongation of the epidermis, so
that, when the leaf separates, "the tree does not suffer from the
effects of an open wound." " The provision for the separation being
once complete, it requires little to effect it ; a desiccation of one side
of the leafstalk, by causing an effort of torsion, will readily break
through the small remains of the fibro-vascular bundles ; or the in-
creased size of the coming leaf-bud will snap them ; or, if these
causes are not in operation, a gust of wind, a heavy shower, or even
the simple weight of the lamina, will be enough to disrupt the small
connections and send the suicidal member to its grave. Such is the
history of the fall of the leaf. We have found that it is not an ac-
cidental occurrence, arising simply from the vicissitudes of tempera-
ture and the like, but a regular and vital process, which commences
with the first formation of the organ, and is completed only when
that is no longer useful ; and we cannot help admiring the wonder-
ful provision that heals the wound even before it is absolutely made,
and affords a covering from atmospheric changes before the part can
be subjected to them." * Leaves fall by an articulation in most
Exogenous plants, where the insertion usually occupies only a
moderate part of the circumference of the stem, and especially in
those with woody stems which continue to increase in diameter.
When they are not cast off in autumn, therefore, the disruption
inevitably takes place the next spring, or whenever the circumfer-

* Dr. Inman, in Henfrey's Botanical Gazette, Vol. 1. p. Gl.
15*

174 THE LEAVES.

ence further enlarges. But in most Endogenous plants, -where the
leaves are scarcely, if at all, articulated with the stem, which in-
creases little in diameter subsequent to its early growth, they are
not thrown off, but simply wither and decay ; their dead bases or
petioles being often persistent for a long time.

311. TllC Death of the Leaf, however, in these and other cases, is
still to be explained. Why have leaves such a temporary exist-
ence ? Why in ordinary cases do they last only for a single year,
or a single summer ? An answer to this question is to be found
in the anatomical structure of the leaf, and the nature and amount
of the fluid which it receives and exhales. The water continually
absorbed by the roots dissolves, as it percolates the soil, a small
portion of earthy matter. In limestone districts especially, it takes
up a sensible quantity of carbonate and sulphate of lime, and be-
comes hard. It likewise dissolves a smaller proportion of silex,
magnesia, potash, &c. A part of this mineral matter (44, 93) is at
once deposited in the woody tissue of the stem ; but a larger por-
tion is carried into the leaves, where, as the water is exhaled
pure, all this earthy substance, not being volatile, must be left be-
hind to incrust the delicate cells of the parenchyma, much as the
vessels in which water is boiled for culinary purposes are in time
incrusted with an earthy deposit. This earthy incrustation, in con-
nection with the deposition of organic solidified matter, must grad-
ually choke the tissue of the leaf, and finally unfit it for the per-
formance of its offices. Hence the fresh leaves most actively fulfil
their functions in spring and early summer ; but languish towards
autumn, and erelong inevitably perish. Hence, although the roots
and branches may be permanent, the necessity that the leaves
should be annually renewed. But the former are, in fact, annually
renewed likewise ; and life abandons the annual layers of wood and
bark almost as soon as it does the leaves they supply (224, 231),
and for similar reasons ; although their situation is such that they
become part of a permanent structure, and serve to convey the sap,
even when no longer endowed with vitality.

312. The general correctness of this view may be tested by direct
microscopical observation. In Fig. 223, 224, some superficial paren-
chyma thus obstructed by long use is represented ; and similar
illustrations may be obtained from ordinary leaves. That this
deposit consists in great part of earthy matter, is shown by care-
fully burning away the organic materials of an autumnal leaf over

EXHALATION' AND THIS KISE OK THE SAP. 175

a lamp, and examining the ashes by the microscope ; which will be
found very perfectly to exhibit the form of the cells. The allies
which remain when a leaf or other vegetable substance is burned
in the open air, represent the earthy materials which it has accu-
mulated. A vernal leaf leaves only a small quantity of ashes ; an
autumnal leaf yields a very large proportion, — from ten to thirty
times as much as the wood of the same species ; although the leaves
contain the deposit of a single season only, while the heart-wood is
loaded with the accumulations of successive years.*

313. Exhalation from the Leaves. The quantity of water exhaled

from the leaves during active vegetation is very great. In one of
the well-known experiments of Hales, a Sunflower three and a half
feet high, with a surface of 5,016 square inches exposed to the air,
was found to perspire at the rate of twenty to thirty ounces avoirdu-
pois every twelve hours, or seventeen times more than a man. A
Vine, with twelve square feet of foliage, exhaled at the rate of five
or six ounces a day ; and a seedling Apple-tree, with eleven square
feet of foliage, lost nine ounces a day. The amount varies witli the
degree of warmth and dryness of the air, and of exposure to light ;
and is also very different in different species, some exhaling more
copiously even than the Sunflower. But when we consider the vast
perspiring surface presented by a large tree in full leaf, it is evident
that the quantity of watery vapor it exhales must be immense.
This exhalation is dependent on the capacity of the air for moisture
at the time, and upon the presence of the sun ; often it is scarcely
perceptible during the night. The Sunflower, in the experiment of
Hales, lost only three ounces in a warm, dry night, and* underwent
no diminution during a dewy night.

314. Rise Of the Sap. Now this exhalation by the leaves requires
a corresponding absorption by the roots. The one is the measure
of the other. If the leaves exhale more in a given time than the
roots can restore by absorption from the soil, the foliage droops ;
as we see in a hot and dry summer afternoon, when the drain by

* The dried leaves of the Elm contain more than eleven per cent of ashes,
while the wood contains less than two per cent ; those of the Willow, more
than eight per cent, while the wood has only 0 45 ; those of the Beech, 6 69,
the wood only 0 36 ; those of the (European) Oak, 4.03, the wood only 0 21 ;
those of the Pitch-Pine, 3.15, the wood only 0 25 per cent. Hence the decaying
foliage in our forests restores to the soil a large proportion of the inorganic
matter which the trees from year to year take from it.

176 THE LEAVE8.

exhalation is very great, while a further supply of moisture can
hardly be extorted from the parched soil ; — as we observe also in
a leafy plant newly transplanted, where the injured rootlets are not
immediately in a fit condition for absorption. Ordinarily, how-
ever, exhalation by the leaves and absorption by the roots are in
direct ratio to each other, and the loss sustained by the leaves is
immediately restored (by endosmosis, 40) through the ascent of the
sap from the branches, the latter being constantly supplied by the
stem ; so that, during active vegetation, the sap ascends from the
remotest rootlets to the highest leaves, at a rate corresponding to
the amount of exhalation. The action of the leaves is, therefore,
the principal mechanical cause of the ascent of the sap. This is
well illustrated when a graft has a different time of leafing from
that of the stock upon which it is made to grow, the graft Avholly
regulating the season or temperature at which the sap is put in
motion, and controlling the habits of the original stock. Also by
introducing the branches of a tree into a conservatory during
winter ; when, as their buds expand, the sap in the trunk Avithout
is set unseasonably into motion to supply the demand.

315. During the summer's vegetation, while the sap is consumed
or exhaled almost as fast as it enters the plant, no considerable ac-
cumulation can take place : but in autumn, when the leaves perish,
the rootlets, buried in the soil beyond the influence of the cold,
which checks all vegetation above ground, continue for a time slowly
to absorb the fluid presented to them. Thus the trunks of many
trees are at this season gorged with sap, which will flow from in-
cisions mafle into the wood. This sap undergoes a gradual change
during the winter, and deposits its solid matter in the cells of the
wood. The absorption recommences in the spring, before new
leaves are expanded to consume the fluid ; chemical changes take
place ; the soluble matters in the tissue of the stem are redissolved,
and the trunk is consequently again gorged with sap, which will
flow, or bleed, when wounded. But when the leaves resume their
functions, or when flowers are developed before the leaves appear,
as in many forest-trees, this stock of rich sap is rapidly consumed,
and the sap will no longer flow from an incision. It is not, there-
fore, at the period when the trunk is most gorged -with sap, in spring
and autumn, but when least so, during summer, that the sap is prob-
ably most rapidly ascending.

PHYSIOLOGY OK VEGETATION. 177

CHAPTER VI.

OF THE FOOD AND NUTRITION OF PLANTS.

Skct. I. The General Physiology of Vegetation.

316. The Organs of Vegetation or Nutrition (tlio.c by which
plants grow and form their various products) having now been con-
sidered, both as to their structure and to fome extent as to their
action, we are prepared to take a comprehensive survey of the
general results of vegetation ; to inquire into the elementary com-
position of plants, the nature of the food by which they are nour-
ished, the sources from which this food is derived, and the transfor-
mations it undergoes in their system. It is in vegetable digestion,
or, to use a better term, in assimilation, that the essential nature of
vegetation is to be sought, since it is in this process alone that min-
eral, unorganized matter is converted into the tissue of plants and
other forms of organized matter (1, 12- 1G). From this point of
view, therefore, the reciprocal relations and influences of the min-
eral, vegetable, and animal kingdoms may be most advantageously
contemplated, and the office of plants in the general economy of the
world best understood. This portion of general physiology is inti-
mately connected with chemistry, and some knowledge of that sci-
ence is requisite for understanding it. We are here restricted to
the bare statement of the leading facts which are thought to be
established, and the more important deductions which may be drawn
from them.

317. While the organs of vegetation have been considered ana-
tomically and morphologically, or in view of their structure and
development, still the leading points of their physiology, or connected
action in the life and growth of the plant, have from time to time
been explained or assumed.

318. The functions of nutrition, which, in the higher animals,
comprise a variety of distinct processes, are reduced to the greatest
degree of simplicity in vegetables. Imbibition, assimilation, and
growth essentially include the whole.

319. Plants absorb their food, entirely in a liquid or gaseous form,
by imbibition, according to the law of endojmo.;is (40), through the

178 THE FOOD AND NUTRITION OF PLANTS.

■walls of the cells that form the surface, principally those of the
newest roots and their fibrils (133). The fluid absorbed by the
roots, mingled in the cells with some previously assimilated matter
they contain in solution ("26, 79), is diffused by exosmosis and endos-
mosis from cell to cell, rising principally in the wood (224, 230) ;
and is attracted into the leaves (or to other parts of the surface of
the plant exposed to the air and light) by the exhalation which
takes place from them (314), and the consequent inspissation of the
sap. Here, exposed to the light of the sun, the crude sap is assimi-
lated, or converted into organizable matter (79) ; and, thus prepared
to form vegetable tissue or any organic product, the elaborated fluid
is attracted into growing parts by endosmosis, in consequence of its
consumption and condensation there, or is diffused through the newer
tissues. There is no movement in plants of the nature of the cir-
culation in animals. Even in the so-called vessels of the latex
there is merely a mechanical flow from the turgid tubes towards the
place where the liquid is escaping when wounded, or from a part
placed under increased pressure (63). The only circulation, or
directly vital movement of fluid, in vegetable tissue, is the cyclosis,
or the system of currents in the layer of protoplasm in young and
active cells (36) : this movement is confined to the individual cell,
and can have no influence in the transference of the sap from cell
to cell. Respiration is likewise a function of animals alone. What
is generally so called in vegetables is connected with assimilation,
and is of entirely different physiological significance, as will pres-
ently be shown. None of the secretions of plants appear, like
many of those of animals, to play any part, at least any essential
part, in nutrition. Many, if" not all of them, are purely chemical
transformations of the general assimilated products of plants, — are
excretions rather than secretions (88 - 90).

320. The appropriation of assimilated matter in vegetable growth,
and the production and multiplication of cells, which make up the
fabric of the plant, have already been treated of (25-34). We
have now mainly to consider what the food of plants is, whence it is
derived, and how it is elaborated.

THKIU ELEMENTARY CONSTITUENTS. 179

Sect. II. The Food and the Elementary Composition
of Plants.

321. TllC Food and the elementary composition of plants stand
in a necessary relation to each other. Since it is not to be sup-
posed that plants possess the power of creating any simple element,
whatever they consist of must have been derived from without.
Their composition indicates their food, and vice versa. If we have
learned the^ chemical composition of a vegetable, and also what it
gives back to the soil and the air, we know consequently what it
must have derived from without, that is, its food. Or, if we have
ascertained what the plant takes from the soil and air, and what it
returns to them, we have learned its chemical composition, namely,
the difference between these two. And when we compare the na-
ture and condition of the materials which the plant takes from the
soil and the air with what it gives back to them, we may form a
correct notion of the influence of vegetation upon the mineral king-
dom. By considering the materials of which plants are composed,
we may learn what their food must necessarily contain.

322. The Constituents of Plants are of two kinds ; the earthy or in-
organic, and the organic. It has been stated (93) that various
earthy matters, dissolved by the water which the roots absorb, are
drawn into the plant, and at length deposited in the wood, leaves,
&e. These form the ashes which are left on burning a leaf or a
piece of wood. Although these mineral matters are often turned
to account by the plant, and some of them are necessary in the
formation of certain products, (as the silex which gives needful
firmness to the stalk of Wheat, and the phosphates which are found
in the grain,) yet none of^ them are essential to simple vegetation,
which may, to a certain extent, proceed without them. These
materials, the presence of which is in some sort accidental, although
for certain purposes essential, are distinguished as the earthy, or
mineral, or inorganic constituents of plants. This class may
be left entirely out of view for the present. But the analysis of
any newly formed vegetable tissue, or of any part of the plant,
such as a piece of wood, after the incrusting mineral matter has
been chemically removed, invariably yields but three or four ele-
ments. These, which are indispensable to vegetation, and make
up at least from eighty-eight to ninety-nine per cent of every vege-

180 THE FOOD AND NUTRITION OK PLANTS.

table substance, are termed tbe universal, organic constituents of
plants. They are Carbon, Hydrogen, Oxygen, and Nitrogen (10,
27). The proper vegetable structure, that is, the tissue itself,
consists of only three of these elements, namely, carbon, hydrogen,
and oxygen ; while the fourth, nitrogen, is an essential constituent
of the protoplasm, which plays so important a part in the formation
of the cells and is an element of one class of vegetable products.

323. The Organic Constituents. These four elements must be fur-
nished by the food upon which the vegetable lives; — they must
be drawn from the soil and the air ; in some cases, doubtless, from
the latter source, as in Epiphytes, or Air-plants (149), but gener-
ally and principally by ab orption through the roots. The plant's
nourishment is wholly received either in the gaseous or the liquid
form ; for the leaves can imbibe air or vapor only, and the roots are
incapable of taking in particles of solid matter, however minutely di-
vided (40, 133).

324. In Avhatever mode imbibed, evidently the main vehicle of
the plant's nourishment is water, which as a liquid or as vapor is
continually in contact with its roots, and in the state of vapor always
surrounds its leaves. We have seen how copiously water is taken
up by the growing plant, and have formed some general idea of its
amount by the quantity that is exhaled unconsumed by the leaves
(313). But pure water, although indispensable, is insufficient for
the nourishment of plants. It consists of oxygen and hydrogen ;
and therefore may furnish, and doubtless does principally furnish,
these two essential elements of the vegetable structure. But it can-
not supply what it does not itself contain, namely, the carbon and
nitrogen which the plant also requires.

325. Yet the question arises, whether the water which the plant
actually imbibes contains in fact a quantity of these remaining
elements. Though pure water cannot, may not rain-water supply
the needful carbon and nitrogen ? It is evident that,- if the water
which in such large quantities rises through the plant, and is ex-
haled from its leaves, contain even a very minute quantity of these
ingredients, in such a form that they may be detained when the
superfluous Avater is exhaled, this might furnish the whole organic
food of the vegetable ; since the plant may condense and accumu-
late the carbon and nitrogen, just as the extremely minute quantity
of earthy matter which the water contains is in time largely accu-
mulated in the leaves and wood.

SOURCE OF THEIR ORGANIC CONSTITUENTS. 181

326. As respects the nitrogen, nearly seventy-nine per cent of
the atmosphere consists of this gas in an uncombined or free state,
that is, merely mingled with oxygen. And, being soluble to some
extent in water, every rain-drop that falls through the air absorbs
and brings to the ground a minute quantity of it, "which is therefore
necessarily introduced into the plant with the water which the roots
imbibe. This accounts for the free nitrogen which is always pres-
ent in plants.

327. The plant also receives nitrogen in the form of ammonia
(or hartshorn), a compound of hydrogen and nitrogen, which is
always produced when any animal and almost any vegetable sub-
stance decays, and which, being very volatile, continually rises into
the air from these and other sources. Besides, it appears to be
formed in the atmosphere, through electrical action in thunder-storms
(in the form of nitrate of ammonia). The extreme solubility of am-
monia and all its compounds prevents its accumulation in the atmos-
phere, from which it is greedily absorbed by aqueous vapor, and
brought down to the ground by rain. That the roots actually ab-
sorb it may be inferred from the familiar facts, that plants grow
most luxuriantly when the soil is supplied with substances which
yield much ammonia, such as animal manures ; and that ammonia
may be detected in the juices of almost all plants. That the am-
monia in the air, and the nitre almost everywhere formed in a fertile
soil, and not the free nitrogen of the atmosphere, take the principal
part in the formation of the protoplasm and other quaternary ele-
ments of plants, is demonstrated by Boussingault's experiments,
showing that a seedling from which all nitrogen is excluded except
the free nitrogen of the air, as it vegetates does not increase the
amount of azotized matter it originally had in the seed, but dimin-
ishes it.* Rain-water, therefore, contains the third element of
vegetation, namely, nitrogen, both in a separate form and in that of
ammonia, &c

328. The source of the remaining constituent, carbon, is still to
be sought. Of this element plants must require a copious supply,
since it forms much the largest portion of their bulk. If the carbon
of a leaf or of a piece of wood be obtained separate from the other
organic elements, — which may be done by charring, that is, by
heating it out of contact Avith the air, so as to drive off the oxygen,

* Comptes Rendus, November 28. 1853, and Ann. Sci. Naturelles, ser. 4, Vol.
1 & 2 (1854) ; also Vol. 7 (1857), showing the part which nitre plays.
16

182 THE FOOD AND NUT1UTTOX OF n.ANTS.

hydrogen, and carbon, — although a small part of the carbon is
necessarily lost in the operation, yet what remains perfectly pre-
serves the shape of the original body, even to that of its most
delicate cells and vessels. With the exception of the ashes, this
consists of carbon, or charcoal, amounting to from forty to sixty
per cent, by weight, of the original material. Carbon is itself a
solid, absolutely insoluble in water, and therefore incapable of as-
sumption by the plant. The chief, if not the only, fluid compound
of carbon which is naturally presented to the plant, is that of car-
bonic acid gas, which consists of carbon united with oxygen. This
gas makes up on the average one 2500th of the bulk of the at-
mosphere ; from which it may be directly absorbed by the leaves.
But, being freely soluble in water up to a certain point, it must also
be carried down by the rain and imbibed by the roots. The car-
bonic acid of the atmosphere is therefore the great source of carbon
for vegetation.

329. It appears, then, that the atmosphere — considering water
in the state of vapor to form a component part of it — contains all
the essential materials for the growth of vegetables, and in the form
best adapted to their use, namely, in the fluid state. It furnishes
water, which is not only food itself, inasmuch as it supplies oxygen
and hydrogen, but is likewise the vehicle of the others, conveying
to the roots what it has gathered from the air, namely, the requisite
supply of nitrogen, either as such or in the form of ammonia, and
of carbon in the form of carbonic acid.

330. These essential elements, the whole proper food of plants,
may be absorbed by the leaves directly from the air, in the state of
gas or vapor. Doubtless most plants actually take in no small part
of their food in this way. Drooping foliage may be revived by
sprinkling with water, or by exposure to a moist atmosphere. A
vigorous branch of the common Live-for-ever (Sedum Telephium),
or of many similar plants, it is well known, will live and grow for a
whole season when pinned to a dry and bare wall ; and the Epi-
phytes, or Air-plants (149), as they are aptly called, must derive
their whole sustenance immediately from the air ; for they have no
connection with the ground. That leaves absorb carbonic acid
directly from the air is readily shown (348).

331. But, as a general statement, it may be said that plants, al-
though they derive their food from the air, receive it mainly through
their roots. The aqueous vapor, condensed into rain or dew, and

SOURCE OF THEIR ORGANIC CONSTITUENTS.. 183

bringing with it to the ground a portion of carbonic acid, and of
nitrogen or ammonia, &c, supplies the appropriate food of the plant
to the rootlets (sometimes in a liquid, but also much of it in a gaseous
form). Imbibed by these, it is conveyed through the stem and into
the leaves, where the superfluous water is restored to the atmosphere
by exhalation,* while the residue is converted into the proper nour-
ishment and substance of the vegetable.

S3 2. The atmosphere is therefore the great storehouse from
which vegetables derive their nourishment ; and it might be clearly
shown that all the constituents of plants, excepting the small earthy
portion that many can do without, have at some period formed a
part of the atmosphere. The vegetable kingdom represents an
amount of matter, which plants have withdrawn from the air, organ-
ized, and confined for a time to the surface.

333. Does it therefore follow, that the soil merely serves as a
foothold to plants, and that all vegetables obtain their whole nour-
ishment directly from the atmosphere ? This must have been the
case with the first plants that grew, when no vegetable or animal
matter existed in the soil ; and no less so with the first vegetation
that covers small volcanic islands raised in our own times from the
sea, or the surface of lava thrown from ordinary volcanoes. No
vegetable matter is brought to these perfectly sterile mineral soils,
except the minute portion contained in the seeds wafted thither by
winds or waves. And yet in time a vast quantity is produced, which
is represented not only by the existing vegetation, but by the mould
that the decay of previous generations has imparted to the soil. We
arrive at the same result by the simple experiment of causing a

* The water exhaled may be again absorbed by the roots, laden with a new
supply of the other elements fiom the air, again exhaled, and so on; as is
beautifully illustrated by the cultivation of plants in closed Ward cases, where
plants are seen to nourish for a long time with a very limited supply of water,
every particle of which (except the small poition actually consumed by the
plants) must pass repeatedly through this circulation. This vegetable micro-
cosm well exhibits the actual relations of water, &c. to vegetation on a large
scale in nature ; where the water is alternately and repeatedly raised by evapo-
ration and recondensed to such extent that what actually falls in rain is esti-
mated to be re-evaporated and rained down (on an average throughout the
world) ten or fifteen times in the course of a year. In this way the atmosphere
is repeatedly washed by the rain ; and those vapors icushed out which else by
their accumulation would prove injurious to men and animals, and conveyed to
the roots of plants, which they are especially adapted to nourish.

184 THE FOOD AND NUTRITION' OF PLANTS.

seed of known weight to germinate on powdered flints, or on a soil
which has been heated (o redness, and watering it with rain-water
alone. When the young plant has attained all the development it is
capable of under these circumstances, it will be found to weigh (after
due allowance for the silex it may have taken up) perhaps fifty or
one hundred times as much as the original seed. There can be no
question as to the source of this vegetable matter in .all these cases.
The requisite materials exist in the air. Plants possess the peculiar
faculty of drawing them from the air. The air must have furnished
the whole. This conclusion is amply confirmed by a great variety of
familial- facts ; such as the continued accumulation of vegetable mat-
ter in peat-bogs, and of mould in neglected fields, in old forests, and
generally wherever vegetation is undisturbed. Since this rich
mould, instead of diminishing, regularly increases with the age of
the forest and the luxuriance of vegetation, the trees must have
drawn from the air, not only the vast amount of carbon, &c. that is
stored up in their trunks, but an additional quantity which is im-
parted to the soil in the annual fall of leaves, &c.

334. Still it by no means follows that each plant draws all. its
nourishment directly from the air. This unquestionably happens
in some of the special cases just mentioned ; with Air-plants, and
with those that first vegetate on volcanic earth, bare rocks, naked
walls, or pure sand. But it is particularly to be remarked, that
only certain tribes of plants Avill continue to live under such cir-
cumstances, and that none of the vegetables most useful as food
for man or the higher animals will thus thrive and come to matu-
rity. In nature, the races of plants that will grow at the entire
expense of the air, such as Lichens, Mosses, Ferns, and certain
tribes of succulent Flowering plants, gradually form a soil of vege-
table mould during their life, which they increase in their decay ;
and the successive generations live more vigorously upon the in-
heritance, being supported partly upon what they draw from the
air, and partly upon the ancestral accumulation of vegetable mould.
Thus, each generation may enrich the soil, even when consisting of
plants that draw largely upon vegetable matter thus accumulated ;
for these annually restore a portion by their dead leaves, &c., and
when they die they may bequeath to the soil, not only all that they
took from it, but all that they drew from the air. It is in this way
that the lower tribes and so-called useless plants create a soil, which
will in time support the higher plants, of immediate importance to

SOURCE OF THEIR ORGANIC CONSTITUENTS. 185

man and the higher animals, but which could never grow and per-
fect their fruit, if left, like their humble but indispensable predeces-
sors, to derive an unaided subsistence directly from the inorganic
world. "While it is strictly true, therefore, that all the organic ele-
ments have been originally derived from the air, it is not true that
what is contained in almost any given plant, or in any one crop, is
immediately drawn from this source. A part of it is thus supplied,
but in proportions varying greatly in different species and under
different circumstances. Undisturbed vegetation consequently tends
always to enrich the soil. But in agriculture the crop is ordinarily
removed from the land, and with it not only what it ha; taken from
the earth, but also what it has drawn from the air ; and the soil is
accordingly impoverished. Hence the farmer finds it necessary
to follow the example of nature, and to restore to the land, in the
form of manure, an amount substantially equivalent to what he
takes away.

335. The mode in which vegetable mould is turned to account
by growing plants has not yet been sufficiently investigated. Ac-
cording to Liebig, the decaying vegetable matter is not employed
until it has been resolved into its original inorganic elements,
namely, into water, carbonic acid, ammonia, &c. ; which are imbibed
by the roots botli directly in the gaseous state, and when taken up by
the water as it percolates through the soil.* Olliers suppose that a
portion of the food which plants derive from decaying vegetable
matter may consist of soluble, still organic compound-;. The econ-
omy of the greenless parasitic plants (152) is adduced in confirma-
tion of this view : but these are nourished by the foster plant just as
its own flowers are nourished. Decisive evidence to the point ij
furnished by Fungi, the greater part of which live upon decaying
organic matter, and have not the power of forming organizable pro-

* While it may be rightly said, that the proportion of carbonic acid in the
atmosphere is too minute directly to supply ordinary vegetation, especially
that of esculent plants, with sufficient carbon, this cannot be said of the air
contained in the pores and crevices of the soil, at least in any fertile soil. Tiiis
air in the soil contains a far larger proportion of carbonic acid than the atmos-
phere above ; the excess being derived partly by direct absorption or by the
action of rain, and in an enriched soil more largely from the decay of the mate-
rials of former generations of plants. In a recently manured sod, the carbonic
acid ordinarily amounts even to 10 or 20 per cent. Sec Boussingault and Lcwy,
in Ann. Sci. Nat. ser. 3, Vol. 10, p. 13.
1G*

186 THE FOOD AND NUTRITION OV PLANTS.

ducts from inorganic materials ; and there is reason to think, that
some Pluenogamous plants (of which our Monotropa, or Indian Pipe
is one) are nourished in this way.

336. The Earthy Constituents. The mineral substances which form
the inorganic constituents of plants (322) are furnished by the soil,
and are primarily derived from the slow disintegration and decom-
position of the rocks and earths that compose it.* These are dis-
solved, for the most part in very minute proportions, in the water
which percolates the soil, (aided, as to the more insoluble earthy
salts, by the carbonic acid which this water contains,) and with this
water are taken up by the roots. However minute their proportion
in the water which the roots imbibe, the plant concentrates and
accumulates them, by the exhalation of the water from the leaves,
until they amount to an appreciable quantity, often to a pretty large
percentage, of the solid matter of the vegetable. As might be ex-
pected (312), the leaves contain a much larger amount of ashes, or
earthy matter, than the wood, and herbaceous plants more than trees,
in proportion to their weight when dry.f

337. The ashes left after combustion are mostly composed of
the " alkaline chlorides, with the bases of potash and soda, earthy
and metallic phosphates, caustic or carbonate of lime and magnesia,
silica, and oxides of iron and of manganese. Several other sub-
stances are also met with there, but in quantities so small that they
may be neglected." Different species growing in the same soil
appear to take in some portion of all such materials as are natu-

* According to Liehig, the quantity of potash contained in a layer of soil
formed by the disintegration of 40,000 square feet of the following rocks, &c ,
to the depth of twenty inches, is as follows. This quantity of Felspar (a large
component of granite, &c.) contains . . . 1,152,000 lbs.

Clinkstone, ..... from 200,000 to 400,000 "

Basalt, " 47,500 " 75,000 "

Clay-slate, " 100,000 " 200,000 "

Loam, . . . . . . " 87,000 " 300,000 "

The silex yielded to the soil by the gradual decomposition of granite and
other rocks is in the form of a silicate of potash or other alkali, which, though
insoluble in pure water, is slowly acted upon and dissolved by the united action
of water and carbonic acid, or more largely by water impregnated with carbon-
ate of potash, which is abundantly liberated during the natural decomposition
of these rocks.

t The subjoined results, selected from Boussingault, exhihit fn a tabular form
the relative quantities of organic and inorganic constituents iu several kinds of

TIIICIU EARTHY CONSTITUENTS.

187

rally presented to them in solution, but not, however, in the same
proportions, nor in proportion to the relative solubility of these
several substances ; while, on the other hand, the same species in
different localities, and also each of its particular parts or organs,
contains, or tends to contain, the same mineral constituents in nearly
the same proportion. One base, however, is often substituted for
another, equivalent for equivalent, as magnesia for lime, soda for
potash. The roots, therefore, appear to have a certain power of
selection in respect to these mineral materials. Nor is it a valid
objection to this view, that they absorb poisons which destroy them.
These are either organic products, such as opium ; or else are cor-
rosive substances, such as sulphate of copper, which disorganize the
rootlets. For mutilated roots or stems absorb all dissolved materials
of the proper density that are presented to them, not only in much
larger quantity (so long as the cut is fresh) than do uninjured root-
lets, but almost indifferently, and in the same proportion that they
ah orb the water they are dissolved in.

338. In the ashes, only the salts which resist the action of heat,
such as the phosphates, sulphates, and hydrochlorates, are in the
state in which they existed in the plant itself. A great part of the
bases were combined with organic acids, formed in the plant, and
most largely with the oxalic (8G) : these compounds are by incinera-
tion, or by exposure to the air, principally converted into carbonates.

339. It being indispensable to its well-being that a plant should
find in the soil such mineral matters as are necessary to its growth,
we perceive why various species will only flourish in particular soils
or situations ; why plants which take up common salt, &c. are re-
stricted to the sea-shore and to the vicinity of salt-springi ; why

herbage, compared, in several cases, with the root or grain. The water was
previously driven ofF by thorough drying.

£

*B

p.

£

«

i

Carbon,

I*

<►. 3

1

44 80

I

|

1
45 80

i

>

i

48 48

1

38.10, 42 75

43 72

46.06

47 53

46.10

Hvdrogcn,

5 10 5 77

5 10

6 00

5.00

6 09

4.69

5.41

5.80

Oxygen,

30 80 43 58

30 50

44.88

35 57

40 53

37.96

38.79

43 40

Nitrogen,

4 50 1 66

2.30

1.50

231

4.18

2 06

035

2 27

Ashes,

21 50 6.24

17 30

3 90

11.32

3.14

7 76

6.97

2 43

100.00 loo oo

inono ioo on inonn

100 00 100 00

roooo 100 00

188 THE FOOD AXD NUTKITIOX 01-' PLANTS.

numerous weeds which grow chiefly around dwelling-, and follow the
footsteps of man and the domestic animals, flourish only in a soil
abounding in nitrates (their ashes containing a notable quantity
either of nitrate of potash or of lime) ; why the Vine requires alka-
line manures, to replace the large amount of tartrate of potash which
the grapes contain ; and why Pines and Firs, the ashes of which
contain very little alkali, will thrive in thin or sterile soils, while the
Beech, Maple, Elm, &c, abounding with potash, are only found in
strong and fertile land.

340. Where vegetation is undisturbed by man. all these needful
earthy materials, which are drawn from the soil during the growth
of the herbage or forest, are in time restored to it by its decay,
in an equally soluble form, along with organic matter which the
vegetation has formed from the air. But in cultivation, the prod-
uce is carried away, and with it the materials which have been
slowly yielded by the soil. " A medium crop of Wheat takes from
one acre of ground about 12 pounds, a crop of Beans about 20
pounds, and a crop of Beets about 1 1 pounds, of phosphoric acid,
besides a very large quantity of potash and soda. It is obvious that
such a process tends continually to exhaust arable land of the
mineral substances useful to vegetation which it contains, and that a
time must come, when, without supplies of such mineral matters, the

land would become unproductive from their abstraction In

the neighborhood of large and populous towns, for instance, where
the interest of the farmer and market-gardener is to send the largest
possible quantity of produce to market, consuming the least possible
quantity on the spot, the want of saline principles in the soil would
very soon be felt, were it not that for every wagon-load of greens
and carrots, fruit and potatoes, corn and straw, that finds its way
into .the city, a wagon-load of dung, containing each and every one
of these principles locked up in the several crops, is returned to the
land, and proves enough, and often more than enough, to replace all
that has been carried away from it." * The loss must either be
made up by such equivalent return, or the land must lie fallow from

* Boussingault, Economie Rttrale : from the Engl. Trans., p. 493. Further :
" It may he inferred that, in the most frequent ease, namely, that of arable
lands not sufficiently rich to do without manure, there can be no continuous
[independent] cultivation without annexation of meadow ; in other words, one
part of the farm must yield ciops without consuming manure, so that this may
replace the alkaline and earthy salts which are constantly withdrawn hy sue-

TIIK1U KARTHY CONSTITUENTS.

189

time to time until these soluble substances are restored by further
disintegration of the materials of the soil : or meanwhile the more
exhausting crops may be alternated with those that take least from
the soil and most from the air ; or with one which, like clover,
although it takes up 77 pounds of alkali per acre, may be consumed
on the field, so as to restore most of this alkali in the manure for the
succeeding crop.

341. It has been asserted that the advantage of preceding a
wheat crop by' one of Leguminous plants (such as Peas, Clover,
Lucerne, &c), or of roots or tubers, is owing to the fact, that these
leave the phosphates, &c. nearly untouched for the wheat which is
to follow, and which largely abstracts them. The results of Bous-
singault's experiments and analyses show that these products are-
far from having the deficiency of phosphates which was alleged.
" For example, beans and haricots take 20 and 13.7 pounds of
phosphoric acid from every acre of land ; potatoes and beet-root
take 11 and 12.8 pounds of that acid, exactly what is found in a
crop of wheat. Trefoil is equally rich in phosphates with the
sheaves of corn that have gone before it." * His further re-

cessive harvests from another part. Lands enriched by rivers alone permit of a
total and continued export of their produce without exhaustion. Such arc the
fields fertilized by the inundations of the Nile ; and it is difficult to form an idea
of the prodigious quantities of phosphoric acid, magnesia, and potash, which,
in a succession of ages, have passed out of Egypt with her incessant exports of
corn." — p. 503.

* Boussingault, /. c, p. 497. — Subjoined is a table, from the same work, of
the percentage of Mine) al Substances taken up from the sod 1>y wuious plants grown
at Bechelbronn.

Acids

i*

u

_

Substances which

6

•c

a

.%

jielded the Ashes.

'3 3

o

J3

a

.2

•

e a

it

o A

a.
o

1

6

a

1

I
0

J

_C 3

fs

3 ' m c

o

j

S

m

m

0

a

Potatoes.

13.4 7 1 ill 3

27

1.8

5 4 51 5

traces

5 6

0 5

07

Mangel-Wurzel,

16.1 1.6

61

52

70

4 4 39 0

60

80

2 5

42

Turnips,

14 0 10 9

60

2.9

109

4.3 \ 33 7

4 1

6.4

1 2

5.5

Potato-tops,

110 22

108

1 6

2 3

1 8,445

traces

130

5 2

76

Wheat,

0.0 1.0

47.0

traces

2.9

15 9.295

traces

1 3

00

2.4

Wheat-straw,

0 0 1.0

3.1

06

8 5

50| 92

03

67.6

1 0

3.7

Oats,

1.7 10

149

0.5

37

771129

0.0

53 3

13

30

Oat-straw,

3 2 4.1

30

47

8 3

2 8 24 5

44

40 0

21

29

Clover,

25 0 2 5

6 3

26

24 6

6.3,26 6

05

5 3

03

00

Peas,

0.5 4 7

30 1

1.1

101

11 9:353

25

1 5

traces

2.3

French beans,

33 13

26 8

0 1

5 811 5'491

00

1 0 traces

1 I

Horse beans,

1 1 0 1.6 34 2

1 0.7

5 |l 86 452

00

0 5 traces

3 I

190 THE FOOD AND NUTRITION OF PLANTS.

searches seem to show that these crops exhaust the soil less than
the cereal grains, in part at least, on account of the large quantity
of organic matter, rich in nitrogen, which they leave to he incor-
porated with the soil. The theory of rotation in crops, founded hy
De Candolle on the assumption that excretions from the roots of a
plant accumulate in the soil until in time they become injurious
to that crop, but furnish appropriate food for a different species,
is entirely abandoned as an explanation ; and even the fact that
such excretions are formed, at least to any considerable extent, is
not made out. That they could accumulate and remain in the soil
without undergoing decomposition is apparently impossible.

Sect. III. Assimilation, ok Vegetable Digestion, and its
Results.

342. We have reached the conclusion, that the universal food of
plants is rain-water, which has absorbed some carbonic acid gas
and nitrogen (partly in the form of ammonia or of other compounds)
from the air, or dissolved them from the remains of former vegeta-
tion in the soil, whence it has also taken up a variable (yet more or
less essential) quantity of earthy matter.

343. This fluid, imbibed by the roots, and carried upwards
through the stem, receives the name of sap or crude sap (79).
Upon its introduction into the plant, this is at once mingled with
some elaborated sap or soluble organized matter it meets with ;
thus becoming sweet in the Maple, &c., and acquiring different
sensible properties in different species. This latter is already elab-
orated food, and may therefore be immediately employed in vegeta-
ble growth. But the crude sap itself is merely raw material, unor-
ganized or mineral matter, as yet incapable of forming a part of the
living structure. Its conversion into organized mater constitutes
the process of

344. Assimilation, or what, from an analogy with animal life, is
usually termed Vegetable Digestion. To undergo this important
change, the crude sap is attracted into the leaves, or other green
parts of the plant, which constitute the apparatus of assimilation,
where it is exposed to the light of the sun, under which influence
alone can this change be effected. Under the influence of solar
light, the fabric is itself constructed, and the chlorophyll, or green

ASSIMILATION. 191

matter of plants, upon which, or in connection with which, the light
exerts its wonderful action, is first developed. When plants are
made to grow in insufficient light, as when potatoes throw out shoots
in cellars, this green matter is not formed. When light is with-
drawn, it is soon decomposed ; as we see when Celery is blanched
by heaping the soil around its stems. So, also, the naturally green-
less leaves of plants parasitic upon the roots or stems of other species
(152) have no direct power of assimilation, but feed upon and grow
at the expense of already assimilated matter. But all green parts,
such as the cellular outer bark of most herbs, act upon the sap in
the same manner as leaves, even supplying their places in plants
which produce few or no leaves, as in the Cactus, &c. Under the
influence of light, an essential preliminary step in vegetable digestion
is accomplished, namely, the concentration of the crude sap by the
evaporation or exhalation of the now superfluous water, the mechan-
ism and consequences of which have already been considered (313).

345. We have now to consider the further agency of light in vege-
table digestion itself, namely, its action in the leaf upon the concen-
trated sap. Here it accomplishes two unparalleled results, which es-
sentially characterize vegetation, and upon which all organized exist-
ence absolutely depends (1, 1G). These are, — 1st. The chemical
decomposition of one or more of the substances in the sap which
contain oxygen gas, and the liberation of this oxygen at the ordi-
nary temperature of the air. The chemist can liberate oxygen
gas from its compounds only by powerful reagents, or by great
heat. 2d. The transformation of this mineral, inorganic food
into organic matter, — the organized substance of living plants,
and consequently of animals. These two operations, although
separately stated, are in fact but different aspects of one great
process. We contemplate the first, when we consider what the
plant gives back to the air; the second, when we inquire what
it retains as the materials of its own growth. The concentrated sap
is decomposed ; the portion not required in the growth of the plant
is returned to the air ; and the remaining elements are at the same
time rearranged, so as to form peculiar organic products.

346. The principal material given back to the air, in this pro-
cess, is oxygen gas,* that element of our atmosphere which alone

* A small proportion of nitrogen gas is likewise almost constantly exhaled
from the leaves ; but this appears to come from the nitrogen which the water

192 THE FOOD AND NUTRITION OF PLANTS.

renders it fit for the breathing and life of animals. That the foliage
of plants in sunshine is continually yielding oxygen gas to the sur-
rounding air has been familiarly known since the days of Ingenhouss
and Priestley, and may at any moment he verified by simple experi-
ment. The readiest way is, to expose a few freshly gathered leaves
to the sunshine in a glass vessel filled with water, and to collect the
air-bubbles which presently arise while the light falls upon them,
but which cease to appear when placed in shadow. This air, when
examined, proves to be free oxygen gas. In nature, diffused day-
light produces this effect ; but in our experiments, direct sunshine is
generally necessary to show it. What is the source of this oxygen
gas, which is given up to the air just in proportion to the vigor of
assimilation in the leafy plant, or, in other words, to the consumption
of crude sap ?

347. This will be manifest on comparing the materials with the
general products of vegetation, — what the plant takes as its food,
with what it makes of it, in growth. Suppose the plant is assimi-
lating its food immediately into its fabric, viz. into Cellulose, or the
substance of which its tissue consists (27). This matter, when in a
pure state, and free from incrusting materials, has a perfectly uni-
form composition in all plants. It is composed of carbon, hydrogen,
and oxygen, the latter two existing in the same proportions as in
water.* It may therefore be said to consist of carbon and the ele-
ments of water. These materials are necessarily furnished by the
plant's food. The mineral food of the plant, from which its fabric
is made (329), is carbonic acid and water. If this be decomposed
in vegetation, and the carbonic acid give up its oxygen, carbon and
the elements of water remain, — the very composition of cellulose or
vegetable tissue. Doubtless, then, the oxygen which is rendered to
the air in vegetation comes from the carbonic acid which the plant
took from the air (328).

348. This view may be confirmed by direct experiment. We

imbibed by the roots bad absorbed from the air (326), and which passes off un-
altered fiom the leaves when this water is evaporated, or from nitiogen in the
air which the rootlets directly absorb. In the course of vegetation, no more
nitrogen is given out than what is thus taken in, and probably not so much.
So that the exhalation of nitrogen may be left out of the general view of the
changes which arc brought about in vegetation.

* Cellulose is chemically composed of 12 equivalents of Carbon, 10 of Hy-
drogen, and 10 of Oxygen, viz. Cic, Hjo, O.o.

ASSIMILATION. 193

have seen that many plants must, and all mag, imbibe the "whole or
a part of their food directly from the air into their leaves (330).
A14 leafy plants evidently obtain a part of their carbonic acid in this
way. It is accordingly found, that when a current of carbonic acid
is made slowly to traverse a glass globe containing a leafy plant ex-
posed to full sunshine, some carbonic acid disappears, and an equal
bulk of oxygen gas supplies its place. Now, since carbonic acid gas
contains just its own bulk of oxygen, it is evident that what has thus
been decomposed in the leaves has returned all its oxygen to the
air. Plants take carbonic acid from the atmosphere, therefore
(directly or indirectly) ; they retain its carbon ; they give back its
oxygen.*

349. But cellulose, being the final, insoluble product of vegetation
appropriated as tissue, can hardly be directly formed in the first in-
stance. The substances from which it must originate, and which
actually abound 'in the elaborated sap, are Dextrine or Vegetable
Mucilage (79, 83), Sugar (80), &c. The first of these is probably
directly produced in assimilation. Its chemical composition is the
same as that of pure cellulose : it consists, not only of the same
three elements, but of the same elements in exactly the same pro-
portion. Dextrine, vegetable mucrlage, &c. are the primary, as yet>
unappropriated materials of vegetable tissue, or unsolidified cellu-
lose, and their production from the crude sap is attended with the
evolution of the oxygen which was contained in the carbonic acid
of the plant's food, as already stated. Nor Avould the result in any
respect be altered if Starch were directly produced. This substance
is merely dextrine, which, instead of being immediately appropriated
in growth, is condensed into solid grains, and in that compact and

* At least, the result is as if the oxygen exhaled were all thus detached from
the carbon of the carbonic acid. Just this amount is liberated, and the facts
obviously point to the carbonic acid as its real source. But, on the other hand,
it appears unlikely that a substance which holds oxygen with such strong affinity
as carbon should yield the whole of it under these circumstances : and water ia
certainly decomposed, with the evolution of oxygen, in the formation of a class
of vegetable products soon to be mentioned ; besides, Edwards and Colin have
shown that water is directly decomposed during germination. Still, as no one
supposes that the residue after the liberation of oxygen is carbon and water,
but only the three elements in the proportions which would constitute them, it
amounts to nearly the same thing whether we say that the oxygen of the. carbonic
acid, or an amount of oxygen equivalent to that of the carbonic acid, derived paitly
from it and partly from the water, is liberated in such cases.
17

194 THE FOOD AND NUTRITION OF PLANTS.

temporarily insoluble form accumulated as the ready prepared ma-
terials of future growth (82). Notwithstanding the difference in
their properties and chemical reactions, these and other general
ternary products (79) are strictly isomeric ; that is, they consist of
the same elements, combined in the same proportions ; and physi-
ologically they are merely different states of one and the same thing.
Dextrine is the most soluble state, and is probably that originally
formed in assimilation in the foliage : starch, amyloid (83), &c. are
temporarily solidified states ; and cellulose is the ultimate and usu-
ally permanent insoluble condition. Accordingly, whenever the ma-
terials of growth are supplied from accumulations of nourishment,
as especially from the seed in germination (123-125), from fleshy
roots (145), rootstocks, tubers, &c. (188-194), the starch or its
equivalent is dissolved in the sap, being spontaneously reconverted
into dextrine and sugar, and attracted in a liquid state into the
growing parts, where, transformed into cellulose, it becomes a por-
tion of the permanent vegetable fabric.

350. If, however, we suppose sugar to be a direct product of the
assimilation of carbonic acid and water, the amount of oxygen gas
exhaled will be just the same as before. For this has the same
elementary composition as dextrine, starch, and cellulose, with the
addition of one or two equivalents of water according to the kind.*
And when formed as a transformation of dextrine, then the latter
has only to appropriate some water. In the origination of all these
products, therefore, the same quantity of carbonic acid is consumed,
and all its oxygen restored to the air.f It is more and more evident,

* The formula for cane-sugar is C12, Hn, On ; for grape-sugar, C12, H12, On.

t Since all these neutral ternary substances are identical, or nearly so, in ele-
mentary composition, and since, with the same amount of carbon, derived from
the decomposition of carbonic acid, the plant can form them all, it will no longer
appear surprising that they should be so readily convertible into each other in
the living plant, and even in the hands of the chemist. But the chemistry of
organic nature exceeds the resources of science, and constantly produces trans-
formations which the chemist in his laboratory is unable to effect. The latter
can change starch into dextrine, and dextrine into sugar ; but he cannot reverse
the process, and convert sugar into dextrine, or dextrine into starch. In the
plant, however, all these various transformations are continually taking place.
Thus, the starch deposited in the seed of the Sugar-cane, Indian Corn, &c. is
changed into sugar in germination ; and the sugar which fills the tissue of the
stem at the time of flowering is rapidly canied into the flowers, where a portion
is transformed into starch and again deposited in the newly -foimed seeds. And

ASSIMILATION. 105

therefore, that, by just so much as plants grow, they take carbonic
acid from the air, they retain its carbon, and return its oxygen.

351. In the production of that modification of cellulose called
Llgnine (42), which abounds in wood (if this be really a simple
product, and not a mixture), not only must a larger amount of car-
bonic acid be decomposed, but a small portion of water also, with
the liberation of its oxygen. For the composition attributed to it
shows that it contains less oxygen than would suffice to convert its
hydrogen into water.*

352. The whole class of fatty substances, including the Oils, Wax,
Chlorophyll (84, 88, 92), &c, contain, some of them no oxygen at
all (such as caoutchouc and Pine-oil), and all of them less oxygen
than is requisite to convert their hydrogen into water. In their
direct formation, if this be supposed, not only all the oxygen of the
carbonic acid has been given out, but also a portion belonging to the
•water. If formed by a further deoxidation of neutral ternary pro-
ducts, the same result is attained as respects the liberation of oxy-
gen gas, but by two or more steps instead of one. The Resins,
doubtless, are not direct vegetable products, but originate from the
alternation and partial oxidation of the essential oils. Balsams,
which exude from the bark .of certain plants, are natural solutions of
resins in their essential oils, as rosin, or Pine-resin, in the oil of tur-
pentine.

3o3. An opposite class, the Vegetable Acids (8G), contain more
oxygen than is necessary for the conversion of their hydrogen into
water, but less than the amount which exists in carbonic acid and
water. Indeed, the most general vegetable acid, the oxalic (which
may be formed artificially by the action of nitric acid on starch),
has no hydrogen, except in the atom of water that is connected with
it. Acids are sometimes formed in the leaves, as in the Sorrel, the

although the chemist is unable to transform starch, sugar, &e. into cellulose, yet
he readily effects the opposite change, by reconverting woody fibre, &c. (under
the influence of sulphuric acid) into dextrine and sugar. The plant docs the
same thing in the ripening of fruits, during which a portion of tissue is often
transformed into sugar. Starch-giains and cellulose can never be formed arti-
ficially, because they are not merely organizable matter, but have an organic
structure.

* According to Pa yen, ligninc, separated as much as possible from cellulose,
consists of Carbon 53.8, Hydrogen 6.0, and Oxygen 40 2 per cent, = C&, Hsi,
0*.

106 TriE FOOD AND NUTRITION OF PLANTS.

Grape-vine, &c, but usually in the fruit. If produced directly from
the sap, as they may be in acid leave-, only a part of the oxygen in
the carbonic acid which contributes to their formation -would be ex-
haled. But if formed from sugar, or any other of the general pro-
ducts of the proper juice, the absorption of a portion of oxygen from
the air would be required for the conversion ; and this absorption
takes place (at least in some cases) when fruits acquire their acidity.
Even their formation by the plant, therefore, is attended by the lib-
eration of oxygen gas, though in less quantity than in ordinary vege-
tation.

354. There is still another class of vegetable products of uni-
versal occurrence, and, although comparatively small in quantity in
plants, yet of as high importance as those which constitute their
permanent fabric ; namely, the neutral quaternary organic com-
pounds, of which nitrogen is a constituent (79). These, also, are
mutually convertible bodies, related to each other as dextrine and
sugar are to starch and cellulose, and playing the same part in the
animal economy that the neutral ternary jjroducts do in the vege-
table, i. e. forming the fabric of animals. The basis or type of
these azotized products has received the name of Proteine (27) :
hence they are sometimes collectively called proteine compounds.
In their production from the plant's food, the ammonia, or other
azotized matter it contains, plays an essential part ; and oxygen gas
is restored to the air from the decomposition of all the carbonic acid
concerned and of a part of the water.*

355. In living cells the proteine forms the protoplasm, or vitally
active lining, which may be said to give origin to the vegetable
structure, since the cellulose is deposited under its influence to
form the permanent walls or fabric of the cells, as has already been
explained (2G-3G). When the cells have completed their growth

* The chemical changes have hecn tabulated thus : —

The materials :

From which are formed the product :

C H.

K 0.

C. H.

N. 0.

74 of Water, 74

74

1 of Froteine, 48 36

6 14

94 of Carbonic acid, 94

188

4 of Cellulose, 48 40

40

2 of Carbonate of

212 of Oxygen lib-

ammonia, 2 2

6 4

erated,

212

9G 76 6 2G6 96 76 6 266

Besides, proteine either contains or U naturally combined with a small quan-
tity of sulphur and phosphorus (10).

ASSIMILATION*. 197

and transformation, the protoplasm abandons tliem, the portion which
is not decomposed being constantly attracted onwards into forming
and growing parts, where it incites new development. For this
azotized matter has the remarkable peculiarity of inducing chemical
changes in other organic products, especially the neutral ternary
bodies, causing one kind to be transformed into another, or even the
decomposition of a part into alcohol, acetic acid, and finally into
carbonic acid and Avater (as in germination, &c), — itself remaining
the while essentially unaltered.

356. The constant attraction of the protoplasm from the com-
pleted into the forming parts of the plants explains how it is, that
so small a percentage of azotized matter should be capable of
playing such an all-important part in the vegetable economy. It
does its work with little loss of material, and no portion of it is fixed
in the tissues. At least, the little that remains in old parts is capa-
ble of being washed out, showing that it forms no integral part of
the fabric. This explains why the heartwood of trees yields barely
a trace of nitrogen, while the sap-wood yields an appreciable amount,
and the cambium-layer and all parts of recent formation, such as the
buds, young shoots, and rootlets, always contain a notable proportion
of it. This gives the reason, also, why sap-wood is so liable to decay
(induced by the proteine), the more so in proportion to its newness
and the quantity of sap it contains, while the completed heart-wood
is so durable. The azotized matter rapidly diminishes in the stem
and herbage during flowering, while it accumulates in the forming
fruit, and is finally condensed in the seedj (which have a larger per-
centage than any other organ), ready to subserve the same ollice in
the development of the embryo plant it contains.*

357. When wheat-flour, kneaded into dough, is subjected to the
prolonged action of water, the starch is washed away, and a tena-
cious, elastic residue, the Gluten of the flour, which gives it the
capability of being raised, remains. This contains nearly all the
proteine compounds of the seed, mixed with some fatty matters
(which may be removed by alcohol and ether) and with a little
cellulose. The azotized products constitute from eight to thirty
per cent of the weight of wheat-flour : the proportion varies greatly

* The cotyledons of peas and beans, according to Mr. Rigg, contain from
100 to 140 parts, and the plumule about 200 parts, of nitrogen, to 1,000 parts of
carbon.

17*

198 THE FOOD AND NUTRITION OF PLANTS.

under different circumstances, but it is always largest when tbe Foil
is well supplied with manures that abound in nitrogen. The gluten
of wheat is a mixture of four isomeric quaternary products, distin-
guished by chemists under the names Fibrine (identical in nature
with that which forms the muscles of animals), Albumen (of the same
nature as animal albumen), Caserne (identical with the curd of milk),
and Glut hie. In beans and all kinds of pulse, or seeds of Legu-
minous plants, the azotized matter principally occurs in the form
of Legumine, which is nearly intermediate hi character between albu-
men and caseine.

358. Comparing now these principal products of assimilation in
plants with the inorganic materials from which they must needs be
formed, it may clearly be perceived that the principal result of vege-
tation, as concerns the atmosphere, from which plants draw then-
food, consists in the withdrawal of water, of a little ammonia, and of
a large proportion of carbonic acid, and of the restoration of oxygen.
The latter is a constant effect of vegetation and the measure of its
amount. As respects the fabric of the plant, the sole consequences
of its formation upon the air are the withdrawal of a small quantity
of water, and of a large amount of carbonic acid gas, and the resto-
ration of the oxygen of the latter. In the formation of its azotized
materials, a portion of ammonia or of some equivalent compound of
nitrogen is also withdrawn. It is true, indeed, that leaves decom-
pose carbonic acid only in daylight ; and that they sometimes give a
quantity of carbonic acid to the air in the night, especially when
vegetation languishes, or even take from it a little oxygen. But
this does not affect the general result, nor require any qualification
of the general statement. The work simply ceases .when light is
withdrawn. The plant is then merely in a passive state. Yet,
whenever exhalation from the leaves slowly continues in darkness,
the carbonic acid which the water holds necessarily flies off with it,
during the interruption to vegetation, into the atmosphere from
which the plant took it. So much of the crude sap, or raw mate-
rial, merely runs to waste. Furthermore, it must be remembered
that the decomposition of carbonic acid in vegetation is in direct op-
position to ordinary chemical affinity ; or, in other words, that all
organized matter is in a state corresponding to that of unstable
equilibrium. Consequently, when light is withdrawn, ordinary
chemical forces may perhaps to some extent resume their sway, the
oxygen of the air combine with some of the newly deposited carbon

INFLUENCE OF VEGETATION ON THE ATMOSPHERE. 199

to reproduce a little carbonic acid, and thus demolish a portion of
the l-ising vegetable structure which the setting sun left, as it were,
in an unfinished or unstable state. This is what actually takes place
in a dead plant at all times, and whenever an herb is kept in pro-
longed darkness ; chemical forces, exerting their power uncontrolled,
demolish the whole vegetable fabric, beginning with the chlorophyll
(as we observe in blanching Celery), and at length resolve it into
the carbonic acid and water from which it was formed. But this
must all be placed to the account of decomposing, not of growing
vegetation ; and even if it were a universal phenomenon, which is
by no means the case,* would not affect the general statement, that,
by so much as plants grow, they decompose carbonic acid and give
its oxygen to the air ; or, in other words, purify the air.

859. Every six pounds of carbon in existing plants have withdrawn
twenty-two pounds of carbonic acid gas from the atmosphere, and
replaced it with sixteen pounds of oxygen gas, occupying the same
bulk. To form some general conception of the extent of the influ-
ence of vegetation upon the air we breathe, therefore, we should
compute the quantity of carbon, or charcoal, that is contained in the

* It is stated that many ordinary plants, when in full health and vigorous
vegetation, impart no carbonic acid to the air during the night — See Pcpys, in
Philosophical Transactions, for 18-13. — Plants deteriorate the air only in then-
decay, and in peculiar processes, distinct from vegetation and directly the re-
verse of assimilation ; as in germination, for instance, where the protcinc in-
duces the decomposition of a portion of the store of assimilated matter, in order
that the rest may he brought into a serviceable condition. The evolution of
carbonic acid by plants, therefore, when it occurs, is no pa it of vegetation. And
it is by a false analogy that tliis loss which plants sustain in the night has been
dignified with the name of vegetable respiration, and vegetables said to vitiate the
atmosphere, just like animals, by their respiration, while they purify it by their
digestion If, indeed, this were a constant function, in any way contributing to
maintain the life and health of the plant, it might be properly enough compared
with the respiration of animals, which is itself a decomposing operation. But
this is not the case. And herein is a characteristic difference between vegetables
and animals : the tissues of the latter require constant interstitial renewal by
nutrition, new particles replacing the old, which arc removed and lcstored to the
mineral world by respiration: while in plants there is no such renewal, but the
fabric, once completed, remains unchanged, ceases to be nourished, and conse-
quently soon loses its vitality; while new parts arc continually formed farther
on to take their places, to be <n turn abandoned Plants, therefore, having no
decomposition and reeomposition of any completed labile, cannot properly be
said to have the function of respiration.

200 THE FOOD AND NUTRITION OF TLANTS.

forests and herbage of the world, and add to the estimate all that
exists in the soil, as vegetable mould, peat, and in other forms ; all
that is locked up in the vast deposits of coal (the product of the
vegetation of bygone ages) ; and, finally, all that pertains to the-
whole existent animal kingdom; — and we shall have the aggregate
amount of a single, though the largest, element which vegetation has
withdrawn from the atmosphere. By multiplying this vast amount
of carbon by sixteen, and dividing it by six, Ave obtain an expression
of the number of pounds of oxygen gas that have in this process
been supplied to the atmosphere.

3 GO. Rightly to understand the object and consequences of this
immense operation, which has been going on ever since vegetation
began, it should be noted, that, so far as we know, vegetation is
the only operation in nature which gives to the air free oxygen gas,
that indispensable requisite to animal life. There is no other pro-
vision for maintaining the supply. The prevailing chemical ten-
dencies, on the contrary, take oxygen from" the air. Few of the
materials of the earth's crust are saturated with it ; some of them
still absorb a portion from the air in the changes they undergo ;
and none of them give it back in the free state in which they took
it, — in a state to support animal life, — by any known natural
process, at least upon any considerable scale. Animals all con-
sume oxygen at every moment of their life, giving to the air carbonic
acid in its room ; and when dead, their bodies consume a further por-
tion in decomposition. Decomposing vegetable matter produces the
same result. Its carbon, taking oxygen from the air, is likewise
restored in the form of carbonic acid. Combustion, as in burning
our fuel, amounts to precisely the same thing ; it is merely rapid
decay. The carbon which the trees oi' the forest have been for
centuries gathering from the air, their prostrate decaying trunks
may almost as slowly restore to the air, in the original form of
carbonic acid. But if set on fire, the same result may be accom-
plished in a day. All these causes conspire to rob the air of its
life-sustaining oxygen. The original supply is indeed so vast, that,
were there no natural compensation, centuries upon centuries would
elapse before the amount of oxygen could be so much reduced, or
that of carbonic acid increased, as to affect the existence of the
present races of animals. But such a period would eventually
arrive, were there no natural provision for the decomposition of the
carbonic acid constantly poured into the air from these various

RELATIONS OF THE VEGETABLE AND ANIMAL KINGDOMS. 201

sources, and for the- restoration of its oxygen. The needful com-
pensation is found in the vegetable kingdom. While animals con-
sume the oxygen of the air, and give back carbonic acid which is
injurious to their life, this carbonic acid is the principal element of
the food of vegetables, is consumed and decomposed by them, and
its oxygen restored for the use of animals. Hence the perfect adap-
tation of the two great kingdoms of living beings to each other; —
each removing from the atmosphere what would be noxious to the
other; — each yielding to the atmosphere what is essential to the
continued existence of the other.*

361. The relations of simple vegetation, under this aspect, to the
mineral kingdom on the one hand, and the animal kingdom on the
other, are simply set forth in the first part of the diagram placed at
the close of this chapter.

362. But, besides this remotely essential office in purifying the
air, the vegetable kingdom renders to the animal another service
so immediate, that its failure for a single year would nearly depop-
ulate the earth; namely, in providing the necessary food for the
whole animal kingdom. It is under this view that the great office
of vegetation in the general economy of the world is to be contem-
plated. Plants are the sole producers of nourishment. They alone
transform mineral, chiefly atmospheric materials, they condense air,
into organized matter. While they thus produce upon a vast scale,
they consume or destroy comparatively little ; and this never in
proper vegetation, but in some special processes hereafter to be con-
sidered (370). Often Avhen they appear to consume their own pro-
ducts, they only transform and transfer them, as when the starch
of the potato is converted into new shoots and foliage.

363. Animals consume what vegetables produce. They them-
selves produce nothing directly from the mineral world. The
herbivorous animals take from vegetables the organized matter
which they have produced \ — a part of it they consume, and in
respiration restore the materials to the atmosphere, from which

* It is plain, however, that, while the animal kingdom is entirely dependent
on the vegetable, the latter is independent of the former, and might have
existed alone. The decaying races of plants, giving back their carbon to the
air and to the soil by decay, would furnish food for their successors. And since
all the carbonic acid which animals render to the air in respiration they have
derived from their vegetable food, this would in time have found its way back to
the air, for the use of new generations of plants, without the intervention of
animals. At most, they merely expedite its return.

202 THK FOOD AND NUTRITION OF TLAXTS.

plants derived them, in the very form in which they were taken,
namely, as carbonic acid and water. The portion they accumulate
in their tissues constitutes the food of carnivorous animals ; who
consume and return to the air the greater part during life, and the
remainder in decay after death. The atmosphere, therefore, out of
which plants create nourishment, and to which animals as they con-
sume return it, forms the necessary link between the animal and
vegetable kingdom-;, and completes the great cycle of organic exist-
ence. Organized matter passes through various stages in vege-
tables, through others in the herbivorous animals, and undergoes its
final transformations in the carnivorous animals. Portions are con-
sumed at every stage, and restored to the mineral kingdom, to which
the whole, having accomplished its revolution, finally returns.

3G4. Moreover, plants not only furnish all the materials of the
animal fabric, but furnish each principal constituent ready formed,
so that the animal has only to appropriate it. The food of animals
is of two kinds ; — 1. that which serves to support respiration and
maintain the animal heat; 2. that which is capable of forming a
portion of the animal fabric, of its flesh and bones. The ternary
vegetable products furnish the first, in the form of sugar, vegetable
jelly, starch, oil, &c, and even cellulose ; substances which, contain-
ing no nitrogen, cannot form an integral part of the animal frame,
but, conveyed into the blood, are decomposed in respiration ; the
carbon and the excess of hydrogen combining with the oxygen of
the air, to which they are restored in the form of carbonic acid and
water. Any portion not required by the immediate demands of res-
piration is stored in the tissues in the form of fat, (which the animal
may either accumulate directly from the oily and waxy matters in
its vegetable food, or produce by an alteration of the starch and
sugar,) as a provision for future use : a deficiency of such materials
subjects the tissues themselves, or the proper supporting food, to im-
mediate decomposition in respiration. The quaternary or azotized
products furnish the proper materials of the animal frame, the
fibrine, caseine, albumen, &c. being directly appropriated from the
vegetable food to form the blood, muscles, &c. ; while a slight trans-
formation of them gives origin to gelatine, of which the sinews, carti-
lages, and the organic part of the bones, consist. The earthy por-
tion of the bones, the iron in the blood, and the saline ingredients
of the animal body, are drawn from the earthy constituents (33G) of
the plants upon which the animal feeds. The animal merely ap-

RELATIONS OF THIC THRICE KINGDOMS OF NATURE.

203

propriates and accumulates these already organizable materials,
changing them, it may be, little by little, as he destroys them, but
rendering them all back (those of the first class through the lungs,
of the second through the kidneys) finally to the earth and air, from
which, and in the condition in which, the vegetable took them.

3G.3. The general relations of vegetation to the mineral and ani-
mal kingdoms are exhibited in the subjoined diagram.

h oa

:■ a

'5.2 =
■°gj

HI
ifl

avg Bo oo

"3 a .T

g3?

£c/j_= 3 o a
c c S-u a a
- § g o « «^j

£ a
1

Si

a

Sz So

5*4

204 FLOWERING AND ITS CONSEQUENCES.

CHAPTER VII.

OP FLOWERING AND ITS CONSEQUENCES.

366. Plants have thus far been considered only as respects
their Organs of Vegetation, — those which essentially constitute
the vegetable being, by which it grows, deriving its support from
the surrounding air and soil, and converting these inorganic mate-
rials into its own organized substance. As every additional supply
of nourishment furnishes materials for the development of new
branches, roots, and leaves, thus multiplying both those organs which
receive food and those which assimilate it, it would seem that, apart
from accidents, 4he increase and extension of plants would be limited
only by the failure of an adequate supply of nourishment. After a
certain period, however, varying in different species, but nearly con-
stant in each, a change ensues, which controls this otherwise indefi-
nite extent of the branches. A portion of the buds, instead of elon-
gating into branches, are developed in the form of Flowers ; and
nourishment which would otherwise contribute to the general in-
crease of the plant, is devoted to their production, and to the matu-
ration of the fruit and seeds.

307. Flowering an Exhaustive Process. Plants begin to bear flowers

at a nearly determinate period for each species ; which is dependent
partly upon constitutional causes, and partly upon the requisite sup-
ply of nutritive matter in their system. For, since the flower and
fruit draw largely upon the powers and nourishment of the plant,
while they yield nothing in return, fructification is an exhaustive
process, and a due accumulation of food is requisite to sustain it.*

* When the branch of a fiuit-trec, which is sterile or docs not perfect its blos-
soms, is ringed or girdled (by the removal of a nanow ring of bark), the elab-
orated juices, being arrested in their downward course, are accumulated in the
branch, which is thus enabled to produce fruit abundantly ; while the shoots that
appear below the ring, being fed by the much weaker ascending sap, do not
blossom, but push forth into leafy branches. So the flowers of most trees and
shrubs that bear large or fleshy fruit are produced from lateral buds, resting
directly upon thd wood of the prc\ious year, in which a quantity of nutritive
matter is deposited. So, also, a seedling shoot, which would not flower for
several years if left to itself, blossoms the next season when inserted as a graft
into an oklcr trunk, f:om whoso accumulated stock it draws.

FLOWERING AN EXHAUSTIVE PROCESS. 205

Annuals flower in a few weeks or months after they spring from the
seed, when they have little nourishment stored up in their tissue ;
and their lives are destroyed hy the process (144) : biennials flower
after a longer period, rapidly exhausting the nourishment accumu-
lated in the root during the previous season, and then perishing
(145) ; while shrubs and trees do not commence flowering until
they arc sufficiently established to endure it. The exhaustion con-
sequent upon flowering, however, is often exhibited in fruit-trees,
which, after producing an excessive crop (especially of late fruits,
such as apples), sometimes fail to bear the succeeding year. When
the crop of one year fails, the- nourishment which it would have ap-
propriated accumulates, and the tree may bear more abundantly the
following season, and so on alternately from year to year.

368. The actual consumption of nourishment in flowering may
be shown in a variety of ways ; as by the rapid disappearance of
the farinaceous or saccharine stoi-e in the roots of the Carrot, Beet,
&c. when they begin to flower, leaving them light, dry, and empty ;
and by the rapid diminution of the sugar in the stalks of the Sugar-
cane and of Maize at the same period. The stalks are therefore
cut for making sugar just before the flowers expand, when they
contain the greatest amount of saccharine matter.

3G9. The consequences of this exhaustion upon the duration of
plants are further illustrated by the facility with which annuals may
be changed into biennials, or their life prolonged indefinitely by
preventing their flowering ; while they perish whenever they bear
flowers and seed, Avhether during the first or any succeeding year.
Thus, a common annual Larkspur has given rise to a double-flowered
variety in the gardens, which bears no seed, and has therefore be-
come a perennial. Cabbage-stumps, which are planted for seed, may
be made to bear heads the second year by destroying the flower-
shoots as they arise ; and the process may be continued from year to
year, thus converting a biennial into a kind of perennial plant. The
effect of flowering upon the longevity of the individual is strikingly
shown by the Agave, or Century -plant, — so called because it flow
ers in our conservatories only after the lapse of a hundred, or at
least a great number of years ; although, in its native sultry climate,
it generally flowers when five or six years old. But whenever this
occurs, the sweet juice with which it is filled at the time (which by
fermentation forms pulque, the inebriating drink of the Mexicans) is
consumed at a rate answering to the astonishing rapidity with which
18

206 H.OWRR1XG AND ITS CONSEQUENCES.

its huge flower-stalk shoots forth (24), and the whole plant inevita-
bly perishes when the seeds have ripened. So, also, the Corypha,
or Talipot-tree, a magnificent Oriental Palm, which lives to a great
age and attains an imposing altitude (bearing a crown of leaves,
each blade of which is often thirty feet in circumference), flowers
only once ; but it then bears an enormous number of blossoms, suc-
ceeded by a crop of nuts sufficient to supply a large district with
seed ; and the tree perishes from the exhaustion.

370. Flowering and fruiting, then, draw largely upon the plant's
resources, while they give back nothing in return. In these opera-
tions, as also in germination, vegetables act as true consumers (like
animals, 3G3), decomposing their own products, and giving back
carbonic acid and water to the air, instead of taking these materials
from the air. It is in flowering that they actually consume most.
In fruiting, although a large quantity of nourishment is taken from
the plants, this is mostly accumulated in the fruit and seed, in a con-
centrated form, for the future use of the new individual in the seed.

371. The real consumption of nourishment by the flower is shown
by the action of flowers upon the air, so different from that of leaves.
While the foliage withdraws carbonic acid from the air, and re-
stores oxygen (346, 358), flowers take a small portion of oxygen
from the air, and give back carbonic acid. While leaves, therefore,
purify the air Ave breathe, flowers contaminate it; though, of course,
only to a degree which is relatively and absolutely insignificant.
This process is necessarily attended by the

372. Evolution of Heat. When carbon is consumed as fuel, and
by the oxygen of the air converted into . carbonic acid, an amount
of heat is evolved directly proportionate to the quantity of carbon
consumed, or of carbonic acid produced. Precisely the same
amount is more slowly generated during the gradual decomposition
of the same quantity of vegetable matter by decay, — a heat which
is employed by the gardener when he makes hot-beds of tan, decay-
ing leaves, and manure, — or by the breathing of animals, which
maintains their elevated temperature (364). The conversion of a
given amount of carbon and hydrogen into carbonic acid and water,
under whatever circumstances it may take place, and whether slowly
or rapidly, generates in all cases the very same amount of heat.
Now, since flowers consume carbon and produce carbonic acid, acting
in this respect like animals, they ought to evolve heat in proportion
to that consumption. This, in fact, they do. The evolution of heat

KVOr.UTION OK HKAT. 207

in blossoming was first observed by Lamarck, about seventy years
ago, in the European Arum, which, just as the flowers open, " grows
hot, as if it were about to burn." It was afterwards shown by Saus-
sure in a number of flowers, such as those of the Bignonia, Gourd,
and Tuberose, and the heat was shown to be in direct proportion to
the consumption of the oxygen of the air, or, in other words, of the
carbon of the plant. The increase of temperature, in these cases,
was measured by common instruments. But now that thermo-elec-
tric apparatus affords the means of measuring variations inappre-
ciable by the most delicate thermometer, the heat generated by an
ordinary cluster of blossoms may be detected. The phenomenon is
most striking in the case of some large tropical plants of the Arum
family, where an immense number of blossoms are crowded together
and muffled by a hooded leaf, or spathe (390), which confines and rever-
berates the heat. In some of these, the temperature rises at times
to twenty or even fifty degrees (Fahrenheit) above that of the sur-
rounding air. This increase of temperature occurs daily, from the
time the flowers open until they fade, but is most striking during the
shedding of the pollen. At night, the temperature falls nearly to
that of the surrounding air ; but in the course of the morning the
heat comes on, as it were like a paroxysm of fere r, attaining the
maximum, day after day, very nearly at the same hour of the after-
noon, and gradually declining towards evening. In ordinary cases,
the heat of flowering is more than counterbalanced by the vaporiza-
tion of the sap and the absorption of solar heat by the foliage; so
that the actual temperature of a leafy plant in summer is lower than
that of the atmosphere.

373. We have remarked that the principal consumption takes
place in the flower ; and that a store is laid up in the fruit and seed.
But much even of this store is consumed when the seed germinates;
and in germination, as is seen in the malting of barley, a large
amount of organic matter- is decomposed into carbonic acid and
water, and a proportionate quantity of heat is evolved. By a not
very violent metaphor it may be said, therefore, that the fabled Phoe-
nix is realized in the Century-plant (3G9), which, after living a hun-
dred years, consumes itself in producing and giving life to its off-
spring, who literally rise from its ashes.

374. Plants need a Season of Rest. When plants are in luxuriant
growth, rapidly pushing forth leafy branches, they are not apt to
produce flower-buds. Our fruit-trees, in \ery moist seasons, or

208 FLOWERING AND ITS CONSEQUENCES.

when cultivated in too rich a foil, often grow luxuriantly, but do not
blossom. The same thing is observed when our Northern fruit-trees
are transported into tropical climates. On the other hand, whatever
checks this continuous growth, without affecting the health of the
individual, causes blossoms to appear earlier and more abundantly
than they otherwise would. It is for this reason that transplanted
fruit-trees incline to blossom the first season after their removal,
though they may not do so again for several years. A state of com-
parative rest seems needful to the transformation by which flowers
are formed. It is in autumn, or at least after the vigorous vegeta-
tion of the season is over, that our trees and shrubs, and most peren-
nial herbs, form the flower-buds of the ensuing year.

375. The requisite annual season of repose, which in temperate
climates is attained by the lowering of the temperature in autumn and
winter, is scarcely less marked in many tropical countries, where
winter is unknown. But the result is there brought about, not by
cold, but by heat and dryness. The Cape of Good Hope, the
Canary Islands, and the southern and interior parts of California,
may be taken as illustrations. In the Canaries, the growing season
is from November to March, — the winter of the northern hemi-
sphere;— their winter also, as it is the coolest season, the mean
temperature being CG° Fahr. But the rains fall regularly, and
vegetation is active ; while in summer, from April to October, it
very seldom rains, and the mean temperature is as high as 73°.
During this dry season, when the scorching sun reduces the soil
nearly to the dryness and consistence of brick, ordinary vegetation
almost completely disappears ; and the Fig-Marigolds, Euphorbias,
and other succulent plants, which, fitted to this condition of things,
alone remain green, not unaptly represent the Firs and other ever-
greens of high northern latitudes. The dry heat there brings about
the same state of vegetable repose as cold with us. The roots and
bulbs then lie dormant beneath the sunburnt crust, just as they do
in our frozen Foil. When the rainy season sets in, and the crust is
softened by moisture, they are excited into growth under a dimin-
ished temperature, just as with us by heat ; and the ready-formed
flower-buds are suddenly developed, cloth. ng at once the arid
waste with a profusion of blossoms (194). The vegetation of such
regions consists mainly of succulents, which are able to live through
the drought and exposure ; of bulbous plants, which run through
their course before the drought becomes revere, then lose their

THK INFLORESCENCE. 209

foliage, while the bud remains quiescent, safely protected under
ground until the rainy season returns ; and of annuals, which make
their whole growth in a few weeks, and ripen their seeds, in which
state the species securely passes the arid season.

37 G. These considerations elucidate the process of forcing plants,
and other operations of horticulture, by which we are enabled to
obtain in winter the flowers and fruits of summer. The gardener
accomplishes these results principally by skilful alterations of the
natural period of repose. He gives the plant an artificial period
of rest by dryness at the season when he cannot command cold,
and then, by the influence of heat, light, and moisture, which he can
always command, causes it to grow at a season when it would have
been cpiiescent. Thus he retards or advances, at will, the periods
of flowering and of rest, or in time completely inverts them.

CHAPTER VIII.

OF THE INFLORESCENCE.

377. Inflorescence is the term used to designate the arrangement
of flowers upon the stem or branch. The flower, like the branch,
is evolved from a bud. Flower-buds and leaf-buds are often so
similar in appearance, that it is difficult to distinguish one from the
other before their expansion. The most conspicuous parts of the
flower are so obviously analogous to the leaves of a branch, that
they arc called in common language the leaves of the flower. Such
a floAver as the double Camellia appears as if composed of a rosette
of white or colored leaves, resembling, except in their color and
texture, the clusters of leaves which are crowded on the offsets of
such plants as the Houseleek (Fig. 207). We therefore naturally
regard a flower-bud as analogous to a leaf-bud ; and a flower, con-
sequently, as analogous to a short leafy branch.

378. This analogy is confirmed by the position which flowers oc-
cupy. They appear at the same situations as ordinary buds, and at
no other ; that is, they occupy the extremity of the stem or branch,
and the axil of the leaves (159, 1G5). Consequently, the arrange-

18*

210 THE INFLORESCENCE.

ment of the leaves governs the whole arrangement of the blosfoms,
as well as that of the branches. The almost endless variety of
modes in which flowers are clustered upon the stem, many of them
exhibiting the most graceful of natural forms, all implicitly follow the
general law which has controlled the whole development of the vege-
table from the beginning. We have, throughout, merely buds termi-
nating the stem and branches, and buds from the axil of the leaves.

379. The simplest kind of inflorescence is, of course, that of a

solitary flower, — a sin-
gle flower-stalk bearing
a single flower ; as in
Fig. 306 and Fig. 327.
The flower is solitary in
both these instances ; but
in the latter case it oc-
cupies the summit of the stem, that is, it stands in the place of
a terminal bud ; in the former it arises from the axil of a leaf, or
represents an axillary bud. These two cases exhibit, in their great-
est simplicity, the two plans of inflorescence, to one or the other of
which all flower-clusters belong.

380. "We begin with the second of these plans ; in which the
flowers all spring from axillary buds ; while the terminal bud, de-
veloping as an ordinary branch, continues the stem or axis indefi-
nitely. For the stem in such case may continue to elongate, and
produce a flower in the axil of every leaf, until its powers are ex-
hausted (Fig. 307). This gives rise, therefore, to what is called

381. Indefinite or Indeterminate Inflorescence. The primary axis is

here never terminated by a flower ; but the secondary axes (from
axillary buds) are thus terminated. The various forms of indefi-
nite inflorescence which in descriptive botany are distinguished by
special names, as might be expected, run into one another through
intermediate gradations. In nature they are not so absolutely fixed
as in our written definitions ; and whether this or that name should
be used in a particular case is often a matter of fancy. The sub-
joined account of the principal kinds will at the same time bring to
view the connection between them.

382. The principal kinds of indefinite inflorescence which have
received distinctive names are the -Raceme, the Corymb, the Umbel,
the Spike, the Mead, the Spadix, the Catkin, and the Panicle.

[FIG. 30G A flowering branch of Moneywort, Lysiiuackia nuumiularia.

INDETERMINATE INFLORESCENCE.

211

383. Before illustrating these, one or two terms, of common oc-
currence, may be defined. A flower which has no stalk to support
it, but winch sits directly on the stem or axis it proceeds from, is
said to be sessile. If raised on a stalk, this is called its PEDUNCLE.
If the whole flower-cluster is raised on a stalk, this

keeps the name of peduncle, or common peduncle (Fig.
307, p) ; and the stalk of each particular flower, if it
have any, takes the name of Pedicel or partial
peduncle (])'). The portion of the general stalk along
which flowers are disposed, is called the axis of in- /O^f
florescence, or, when covered with sessile flowers, the
rhachis (backbone), and sometimes (as when thick
and covered with crowded flowers) the receptacle.
The leaves of a flower-cluster generally are termed
Bkacts. • But when we wish particularly to distin-
guish their sorts, those on the peduncle, or main axis,
and which have a flower in their axil, take the name
of Bracts (Fig. 307, b) ; and those on the pedicels or
partial flower-stalks, if any, that of Bractlets or
Bracteoles (b1). The bracts are often reduced to
a minute size, to as to escape ordinary notice : they
very frequently fall off when the flower-bud in their
axil expands, or even earlier ; and sometimes, as in
the greater part of the Mustard family, they altogether
fail to appear.

384. A Raceme (Fig. 307, 308, 315) is that form of flower-cluster
in which the flowers, each on their own footstalk or pedicel, are
arranged along a common stalk or axis of infloresence ; as in the
Lily of the Valley, Currant, Choke-Cherry, Barberry, &c. The
lowest blossoms of a raceme are of course the oldest, and therefore
open first, and the order of blossoming is ascending, from the bot-
tom to the top. The summit, never being stopped by a terminal
flower, may go on to grow, and often does so (as in the Snowberry,
Shepherd's Purse, &c), producing lateral flowers one after another
throughout the season. In the raceme, the axis of inflorescence is
more or less elongated, and the pedicels are about equal in length.

385. A Corymb (Fig. 309, 319) is the same as a raceme, except
that the lower pedicels are elongated, so as to form a level-topped or
slightly convex bunch of flowers ; as in the Hawthorn, &c.

FIG 307. A Raceme, with a general peduncle (/>), pedicels (//), bracts (6), and bractlets (V).

212

THE INFLORESCENCE.

386. An Umbel (Fipj. 310) differs from a corymb only in having
all the pedicels arising from the same apparent point, so as to resem-
ble the rays of an umbrella; — the general peduncle, in this case,
bearing several flowers without any perceptible elongation of the

axis of infloresence. The Primrose and the Milkweed afford

familiar examples of the simple umbel.

387. A corymb being evidently the same as a raceme with a
short main axis, and an umbel the same
as a corymb with a still shorter axis,
it is evident that the outer flowers of
an umbel or corymb correspond to the
lowermost in the raceme, and that these
will first expand, the blossoming pro-
ceeding regularly from the base to the
apex, or (which is the same thing) from
the circumference to the centre. This
mode of development uniformly takes
place when the flowers arise from axil-
lary buds ; on which account the indefi-
nite mode of inflorescence is also called
the centripetal.

388. In all the foregoing cases, the
flowers are raised on stalks, or pedicels.
"When these are wanting, or so short as
not to be apparent, a Spike or Head is
produced.
389. A Spike is the same. as the raceme, except that the flowers

are sessile ; as in the Plantain (Fig. 311) and Mullein. It is an in-

FIG. 318. A raceme. 309. A corymb. 310. An umbel.

FIG. 311. Young spike of Plautago major 312. Catkin of White Birch.

INDETERMINATE INFLORESCENCE.

213

determinate infloresenee, with the primary axis elongated, and the
flowers destitute of pedicels or with only very short ones. Two
varieties of the spike have received independent names, viz. the
Spadix and the Ament.

390. A Spadix is a fleshy spike enveloped by a large bract or mod-
ified leaf, called a Spathe, as in Calla palustris (Fig. 313), the
Indian Turnip (Fig. 314), and the Skunk Cabbage (Fig. 1205).

391. All Amcnt, or Catkin, is merely that kind of spike with scaly
bracts borne by the Birch (Fig. 312), Poplar, Willow, and, as to one
of the two sorts of flowers, by the Oak, Walnut, and Hickory, which
are accordingly called amentaceous trees. Catkins usually fall off
in one piece, after flowering or fruiting, especially sterile catkins.

392. The Head, or CapitUllim, is a globular cluster of sessile flowers,
like that of Clover, the Button-Bush (Fig. 320), and the balls of the
Buttonwood or Plane-tree. It is a many-flowered centripetal in-
florescence, in which neither the primary axis nor the secondary
axes are at all lengthened. We may view it either as an umhel
without any pedicels, or as a spike with a very short axis. Gen-
erally it is of the latter character, as is evident in a Clover-head,
where what was first a head frequently elongates into a spike as it
grows older.

FIG. 313, 314. Spadix of Calla and of Arum, with the cpathe. 313
317. A eynie. 318. Panicle of Meadow-Grass. 313 A corymb.

A raceme of Cherry.

214 THE INFLORESCENCE.

393. The base both of the head and the umbel is frequently fur-
nished with a number of imperfect leaves or bracts, crowded into a

cluster or whorl, termed an Involucre. The involucre assumes a
great variety of forms ; sometimes resembling a calyx ; and some-

FIG. 320. Head of flowers of the Button-bush, Cephalanthus occidentalis.
FIG 321 Plant of Cornus Canadensis, with its four-leaved iuvolucre around a cluster of Email
owers. 322. A separate flower enlarged.
FIG. 323 Flowering branch of Cichory, with two heads of ligulate flowers.

INDETERMINATE INFLORESCENCE.

215

times (as in Cornus Florida, or tlie common Dogwood, and C. Cana-
densis, Fig. 321) becoming petal-like, and much more showy than
the blossom itself. Here it is at once distinguished from the calyx
or corolla by its including a number of flowers. Sometimes, how-
ever, as in the Mallow and Hibiscus, the involucre forms a kind
of outer calyx to each flower.

394. The axis, or rhachis (382), of a head is called its Recep-
tacle. Frequently, instead of being globular or oblong, it is flat or
depressed, and dilated horizontally, so as to allow a large number of
flowers to stand on its level or merely convex surface ; as in the Sun-
flower, Aster, Marigold, Dandelion, and Cichory (Fig. 323). Here,
as in Fig. 321, a set of bracts form an involucre, surrounding the
dense head of flowers. And as the involucre considerably resembles
a calyx, while the outer flowers, often of a peculiar sort, are readily
mistaken for petals, the head in these and similar plants was called
a compound jiower by the
older botanists. Fig. 324 rep-
resents a section through a
head of such flowers in a Co-
reopsis ; and Fig. 325 is a slice
of the same, more enlarged,
displaying some of the sepa-
rate flowers. In Coreopsis,

as in the Sunflower, Yarrow, 321

&c, each blossom of the head is subtended by its bract (b) ; and
the bracts in such cases are called Paha or Chaff.

395. The Fig presents a ease of very singular inflorescence

FIG 324 Vertical section of a head of flowers of a Coreopsis.

FIG 325. A slice of Fig 321, more enlarged, with one tubular perfect flower (a) left stand-
ing on the receptacle, and subtended by its bract or chaff (b) ; also one ligulate and neutral ray-
flower (c), and part of another: <7, section of bracts or leaves of the involucre.

216

THE INFLORESCENCE.

(Fig. 590 - 592), where the flowers apparently occupy the inside
instead of the outside of the axis, being enclosed within the fleshy
receptacle, which is hollow and nearly closed at the top. So that
while a Sunflower, or the like, is an inflorescence imitating a blos-
som", a fig is an inflorescence imitating a fruit. Indeed, it is much
like a mulberry (Fig. 593) or a pine-apple, turned inside out.

396. The foregoing are all forms of simple inflorescence ; the
ramification not passing beyond the first step; the lateral buds being
at once terminated by a single flower. But the lateral flower-
stalks may themselves branch, just as ordinary branches give rise
to branchlets : then the inflorescence becomes compound. If the
branches of a raceme are prolonged, and bear other flowers on pedi-
cels similarly arranged, a compound raceme is produced ; or if the
flowers are sessile, a compound spike is formed. A corymb, the
branches of which are similarly divided, forms a compound corymb ;
and an umbel, where the branches (often called rays) bear smaller
umbels at their apex, is termed a compound um-
bel ; as in the Caraway, Parsnip, and almost all
the species of the family Umbelliferrc, which is
so named on this account.

397. For these secondary umbels, a good Eng-
Q\ \ / " lish name has been employed by Dr. Darlington,

that of Umbeeeets. Their involucre, when
they have any, is distinguished from that of the
principal umbel by the name of Invoeucee.

398. When the inflorescence is compound, it is
readily seen that the different kinds of inflores-
cence may be combined ; the first ramification
following one plan, and the subdivision another.
The combination is usually expressed by a de-
scriptive phrase, as " spikes racemose, or ra-
cemed," " heads corymbose," &c. The combina-
tion of the raceme and the corymb or the cyme
gives rise to a form of inflorescence which has a
technical name, viz. : —

399. The Panicle. This is formed when the
secondary axes of a raceme branch in a corymbose manner, as in
most Grasses (Fig. 318, 326), or when those of a corymb divide in the
manner of a raceme. And the name is applied to almost any open

FIG. 326. A panicle. (Compare with Fig. 307.)

DETERMINATE INFLORESCENCE.

217

and more or less elongated inflorescence which is irregularly branched
twice, thrice, or a greater number of times.

400. A ThjTSUS, or 'I hyrsc, is a compact panicle of a pyramidal, oval,
or oblong outline ; such as tbe cluster of flowers of the Lilac and
Horsechestnut, a bunch of grapes, &c.

401. Definite or Determinate Inflorescence. In this class, the flowers

all represent terminal buds (380). The primary axis is directly
terminated by a single flower-bud, as in Fig. 327, and its growth
is of course arrested. Here we have a solitary terminal flower.
Further growth can take place only by the development of secondary
axes from axillary buds. These may develop at once as peduncles,
or as leafy branches ; but they are in either case arrested, sooner or
later, by a flower-bud, just as the primary axis was (4Fig. 328). If
further development ensues, it is by the production of branches of the
third order, from the axils of leaves or bracts on the branches of the
second order (Fig. 329) ; and so on. Hence this mode of inflo-
rescence is said to be definite or determinate, in contradistinction to
the indeterminate mode, already treated of, where the primary or
leading axes elongate indefinitely, or merely cease to grow from the
failure of nourishment, or some other extrinsic cause. The most
common and most regular cases of determinate inflorescence occur in
opposite-leaved plants, for obvious reasons ; and such are accordingly
chosen for the subjoined illustrations. But the Rose, Potentilla, and
Buttercup furnish familiar examples of the kind in alternate-leaved
plants.

402. The determinate mode of inflorescence assumes forms which
may closely imitate those of the indeterminate kind, already de-
scribed, and with which they have been confounded. When, for ex-
ample, all the secondary axes connected witli the inflorescence are
arrested by terminal flowers, without any onward growth except

PIG 327 - 329. Diagrams of regular forms of determinate or centrifugal inflorescence.

19

218 THE INFLORESCENCE.

•what forms their footstalks or pedicels, and these are nearly equal in
length, a raceme-like inflorescence is produced, as in Fig. 330 ; or
when the flowers have scarcely any pedicels, the spike is imitated.
These are distinguished from the true raceme and
spike, however, hy the reverse order of development
of the hlossoms ; the terminal one opening earliest, and
the others expanding in succession from above down-
wards ; while the blossoming of the raceme proceeds
from below upwards. Or when, by the elongation of
the lower secondary axes, a corymb is imitated, the
flowers are found to expand in succession from the
centre of each ramiflcation, beginning in the centre of
the cluster, while the contrary occurs in the corymb.
That is, while the order in indeterminate inflorescence
is centripetal (387), that of the determinate mode is
centrifugal. When the determinate inflorescence as-
sumes the flattish or convex form, which it more com-
monly does, it has a distinctive name, viz. : —

403. TllC Cyme This is a flat-topped, rounded or expanded in-
florescence, whether simple or compound, of the determinate class ;
of which those of the Laurustinus, Elder, Dogwood, and Hydrangea
(Fig. 420) are fully developed and characteristic examples. In com-
pound and compact cymes, such as those of the Laurustinus, Dogwood,
&c, the leaves or bracts arc usually minute, rudimentary, or abor-
tive, and all the numerous flower-buds of the cluster are fully formed
before any of them expand ; and the blossoming then runs through
the whole cluster in a short time, commencing in the centre of the
cyme, and then in the centre of each of its branches, and thence pro-
ceeding centrifu gaily. But in the duckweeds (Fig. 331), in Hy-
pericum, and many similar plants, the successive production of the
branches and the evolution of the flowers, beginning with that which
arrests the growth of the primary axis, go on gradually through the
whole summer, until the powers of the plant are exhausted, or until
all the branchlets or peduncles are reduced to single internodes, or
pedicels destitute of leaves, bracts, or bracelets, when no further de-
velopment can take place. Such cases enable us to study the deter-
minate inflorescence to advantage, and to follow the successive steps
of the ramification by direct observation.

404. A Cymillc ( Cymula) is a diminutive cyme, or a branch or
cluster of a compound cyme.

FIG 330 Definite in."orcscence Imitating a raceme.

DETERMINATE INFLORESCENCE.

219

405. The Fascicle is a very compact cyme, with upright or ap-
pressed branches ; as in the Sweet William.

406. A Glomemle is a cyme condensed into a kind of head. It is
to the cyme what the head is to the corymb or umbel.

407. There are several abnormal modifications of definite inflo-
rescence, arising from irregular development, or the suppression of
parts, such as the non-appearance sometimes of the central flower,
or often of one of the lateral branches at each division ; as in the
ultimate ramifications of Fig. 331, where one of the lateral pedicels
is wanting. When this deviation is completely manifested, that is,
when one of the side branches regularly fails, the cyme is apparently
converted into a kind of one-sided raceme, and the flowers seem to
expand from below upwards, or centripetally. The diagram, Fig.
332, when compared with Fig. 331, explains this anomaly. The
place of the axillary branch which fails to develop at each ramifica-
tion is indicated by the dotted

this

lines. Cases like

in several Hypericums,

occur
and
in some other opposite-leaved
plants. An analogous case oc-
curs in many alternate-leaved
plants ; where the stem, being
terminated by a flower, is con-
tinued by a branch from the
axil of the uppermost leaf or
bract ; this, bearing a flower, 332 333

is similarly prolonged by a secondary branch ; that by a third, and
so on ; as is shown in the diagram, Fig. 333. Such forms of inflo-

FIG 331 The open, progressively developed cj me of Alsine Michauxii.
FIG 332, 333. Plan of Uo modifications of helicoid cymes or false racemes.

220 TII1C INFLORESCENCE.

rescence, which we may observe in Drosera, Sedum, and Hounds-
tongue, imitate the raceme so nearly, that they have commonly been
considered as of that kind. They are distinguishable, however, by
the position of the flowers opposite the leaf or bract, or at least out
of its axil; while in the raceme, and in every modification of cen-
tripetal inflorescence, the flowers necessarily spring from the axils.
But if the bracts disappear, as they commonly do in the Forget-me-
not, &c, the true nature of the inflorescence is not readily made out.
The undeveloped summit is usually circulate, or coiled in a spiral
manner (Fig. 219), gradually unrolling as the flowers grow and
expand, and becoming straight in fruit On account of this coiled
arrangement, such cymes or false racemes are said to be helicoid,
or scorpio id.

408. The cyme, raceme, head, &c, as well as the one-flowered
peduncle, may arise, either at the extremity of the stem or leafy
branch {terminal), or in the axil of the leaves (axillary). The case
of a peduncle opposite a leaf, as in the Poke, the Grape-vine, &c, is
just that illustrated in Fig. 333, except that in these cases the peduncles
bear a cluster of flowers instead of a single one. The tendrils of
the Vine (Fig. 161) occupy the same position, and are of the same
nature. In a growing Grape-vine, it is evident that the uppermost
tendril really terminates the stem ; and that the latter is continued
by the growth of the axillary bud, situated between the petiole and
the peduncle ; the branch thus formed, assuming the direction of the
main stem, and appearing to be its prolongation, throws the peduncle
or tendril to the side opposite the leaf.

409. The extra-axillary peduncles of most species of Solanum, &c.
are terminal peduncles, which have become lateral by the evolution
of an axillary branch, with which the peduncle or the petiole is
united for some distance. Such peduncles sometimes come from
extra-axillary accessory buds (169).

410. In the Linden (Fig. 742) the peduncle appears to spring
from the middle of a peculiar foliaceous bract. But this is rather
a bractlet, inserted on the middle of the peduncle, and decurrent
down to its base.

411. A peduncle which arises from the stem at or beneath the
surface of the ground, as in Bloodroot, the Primrose, the so-called
stemless Violets, &c, is called a radical peduncle, or a Scapk.

412. A combination of the two classes of inflorescence is not un-
usual, the general axis developing in one Avay, but the separate

THK FLOWER. 221

flower-clusters in the other. Thus the heads of the Sunflower and
of all the so-called compound flowers (394) are centripetal, the
flowers expanding regularly from the margin or circumference to the
centre ; while the branches that hear the heads are developed in the
centrifugal mode, the central heads being earliest to come into blos-
som. This is exactly reversed in all Labiates (plants of the Mint
tribe) ; where the stem grows on indefinitely, producing axillary
clusters in the form of a general raceme or spike, which blossoms
from below upwards ; while the flowers of each cluster form a cyme,
and expand in the centrifugal manner. These cymes, or cymulcs
(404), are usually close and compact, and being situated one in each
axil of the opposite leaves, the two together frequently form a clus-
ter which surrounds the stem, like a whorl or verticil (as in the.
Catnip and Horehound) : hence such flowers are often said to be
whorled or rerticillate, which is not really the case, as they evidently
all spring from the axils of the two leaves. The apparent verticil
of this kind is sometimes termed a Verticillaster.

413. True whorled flowers occur only in some plants with whorled
leaves, as in Iiippuris and the Water Milfoil.

CHAPTER IX.

OF THE FLOWER.

Sect. I. Its Organs, or Component Parts.

41 4. Having glanced at the circumstances which attend and con-
trol the production of flowers, and considered the laws which govern
their arrangement, we have next to inquire what the flower is com-
posed of.

415. The Flower (117) assumes an endless variety of forms in
different species, so that it is very difficult properly to define it.
The name was earliest applied, as it is still in popular language
generally applied, to the delicate and gayly colored leaves or petals,
so different from the sober green of the foliage. But the petals,
and all these bright hues, are entirely wanting in many flowers,
while ordinary leaves sometimes assume the brilliant coloring of tha

ID*

222

THK FLOWER.

blossom The stamens and pistils are the characteristic organs of
the flower ; but sometimes one or the other of these disappear from
334 a particular flower, and both are absent. from

full double Roses, Camellias, &c, in winch we
have only a regular rosette of delicate leaves.
This, however, is an unnatural state, the conse-
quence of protracted cultivation.

416. The flower consists of the organs of re-
production of a Phrenogamous plant (114), and
their envelopes. A complete flower consists of
the essential organs of reproduction (viz. stamens
and pistils), surrounded by two sets of leaves
or envelopes which protect them. The latter
are 'of course exterior or lower than the former,
which in the bud they enclose.

417. The Floral Envelopes, then, are of two

sorts, and occupy two circles, one above or
Those of the lower circle, the exterior envelope
in the flower-bud, form the Calyx: they commonly exhibit the
green color and have much the appear-
ance of ordinary leaves. Those of the
inner circle, which are commonly of a
more delicate texture and brighter color,
and form the most showy part of the
blossom, compose the Corolla. The
several parts or leaves of the corolla are
called Petals : and the leaves of the
calyx take the corresponding name of Sepals. One of the five
sepals of the flower represented in Fig. 334 is separately shown in
Fig. 336 ; and one of the petals in Fig. 337. The calyx and corolla,
taken together, or the whole floral envelopes, whatever they may con-
sist of, are sometimes called the Perianth (Perianthium or Peri-
goniuni).

418. The Essential Organs of the flower are likewise of two kinds,
and occupy two circles or rows, one within the other. The first of

•within the other

FIG 334 The complete flower of a Crassula 335 Diagram of its cross-section in the bud,
showing the relative position of its parts The five pieces of the exterior circle are sections of
the sepals ; the next, of the petals ; the third, of the stamens through their anthers ; the in-
nermost, of the five pistils.

FIG. 336. A sepal , 337, a petal ; 338, a stamen ; and 339, a pistil from the flower repre-
e«nted in Fig 331.

ITS ORGANS OR PARTS.

223

these, those next within the petals, are the Stamens (Fig. 338).
A stamen consists of a column or stalk, called the Filament (Fig.
340, a), and of a rounded body, or case, termed the An-
ther (b), filled with a powdery substance called Pol-
len, which it discharges through one or more slits or
openings. The older botanists had no general term for
the stamens taken collectively, analogous to that of corolla
for the entire whorl of petals, and of calyx for the whorl
of sepals. A name has, however, recently been pro-
posed for the staminate system of a flower, which it is
occasionally convenient to use ; that of AxDRCECiu.Ar.

419. The remaining, or seed-bearing organs, which occupy the
centre or summit of the flower, to whose protection and perfection
all the other parts of the flower are in some way subservient, are
termed the Pistils. To them collectively the name of Gynjeciu.m
has been applied. One of them is separately shown in Fig. 339.
This is seen more magnified and cut across in Fig. 342 ; and a dif-
ferent one, longitudinally divided,
so as to exhibit the whole length
of its cavity, or cell, is represent-
ed in Fig. 341.

420. A pistil is distinguished
into three parts ; namely, the
Ovary (Fig. 341, a), the hollow
portion at the base which con*
tains the Ovules, or bodies des-
tined to become seeds ; the Style
(&), or columnar prolongation of the apex of the
ovary; and the Stigma (c), a portion of the sur-
face of the style denuded of epidermis, sometimes
a mere point or a small knob at the apex of the
style, but often forming a single or double line
running down a part of its inner face, and assum-
ing a great diversity of appearance in different
plants.

FIG. 340. A stamen, with the anther (6) discharging its pollen : a, the filament.

FIG 341. Vertical section of a pistil, showing the interior of its ovary, o, to one side of
which are attached numerous ovules, d : above is the style, i, tipped by the stigma, c.

FIG. 342. A Pistil of Crnssula, like that of Fig. 339, but more magnified, and cut across
through the ovary, to show its cell, and the ovules it contains. At the summit of the style is
seen a somewhat papillose portion, destitute of epidermis, extending a little way down the in-
ner face : this id the stigma.

224

THE FLOWER.

421. All the organs of the flower are situated on, or grow out of,
the apex of the flower-stalk, into which they are said, in botanical lan-
guage, to be inserted, and which is called the Touts, or Receptacle.
This is the axis of the flower, to which the floral organs are attached
(just as leaves are to the stem) ; the calyx at its very base ; the
petals just within or above the calyx ; the stamens just within the
petals ; and the pistils within or above the stamens (Fig. 343).

d c 422. Such is the struct-

ure of a complete and regu-
lar flower ; which Ave take
as the type, or standard of
comparison.- The calyx
and corolla are termed pro-
tecting organs. Ill the bud,
they envelope the other
parts : the calyx sometimes
forms a covering even for
the fruit ; and when it retains its leaf-like texture and color, it as-
similates the sap of the plant with the evolution of oxygen gas, in
the same manner as do true leaves : the corolla elaborates honey or
other secretions, for the nourishment, as is supposed, of the stamens
and pistils. Neither the calyx nor corolla is essential to a flower,
one or both being not unfrequently wanting. The stamens and pis-
tils are, however, essential organs, since both are necessary to the
production of seed. But even these are not always both present in
the very same flower ; as will be seen when we come to notice the
diverse forms which the blossom assumes, and to compare them with
our pattern flower.

Sect. II.

The Theoretical Structure or General Mor-
phology of the Flower.

423. To obtain at the outset a correct idea of the flower, it is
needful here to consider the relation which its organs sustain to the
organs of vegetation. Taking the blossom as a whole, we have
recognized, in the chapter on Inflorescence (377), the identity of
flower-buds and leaf-buds as to situation, &c. Flowers, consequently,

FIG 343. Tarts of the flower of a Stoneerop, Scdum tematum, two of each sort, and the
receptacle, dispta, ed : a, sepal : 6, petal : c, stamen: (/.pistil.

ITS TIIKOTIKTICAT. STRUCTURE. 225

are at least analogous to branches, and the leaves of the flower are
analogous to ordinary leaves.

424. But the question which now arises is, whether the leaves of
the stem and the leaves and the more peculiar organs of the flower
are not homologous parts, that is, parts of the same fundamental
nature, although developed in different shapes that they may sub-
serve different offices in the vegetable economy ; — just as the arm
of man, the fore-leg of quadrupeds, the wing-like fore-leg of the bat,
the true wing of birds, and even the pectoral fin of fishes, all repre-
sent one and the same organ, although developed under widely dif-
ferent forms and subservient to more or less different ends. The
plant continues for a considerable time to produce buds which de-
velop into branches. At length it produces buds which expand into
blossoms. Is there an entirely new system introduced when flowers
appear ? Are the blossoms formed upon such a different plan, that
the general laws of vegetation, which have sufficed for the interpre-
tation of all the phenomena up to the inflorescence, are to afford no
further clew ? Or, on the contrary, now that peculiar results are to
be attained, are the simple and plastic organs of vegetation — the
stem and leaves — developed in new and peculiar forms for the ac-
complishment of these new ends ? The latter, doubtless, is the cor-
rect view. The plant does not produce essentially new kinds of
organs to fulfil the new conditions, but adopts and adapts the old.
Notwithstanding these new conditions and the successively increas-
ing difference in appearance, the fundamental laws of vegetation
may be traced from the leafy branch into and through the flower.
That is, the parts of the blossom are homologous with leaves, are
leaves in other forms than that of foliage.

425. The student will have observed, that in vegetation no new
organs are introduced to fulfil any particular condition, but the com-
mon elements, the root, stem, and leaves, are developed in peculiar
and fitting forms to subserve each special purpose. Thus, the same
organ which constitutes the stem of an herb, or the trunk of a tree,
we recognize in the trailing vine, or the twiner, spirally climbing
other stems, in the straw of Wheat and other Grasses, in the colum-
nar trunk of the Palm, in the flattened and jointed Opuntia, or
Prickly Pear, and in the rounded, lump-like body of the Melon-
Cactus. So, also, branches harden into spines in the Thorn, or, by
an opposite change, become flexible and attenuated tendrils in the
Vine, and runners in the Strawberry ; or, when developed under

226 TIIK FLOWER.

ground, they assume the aspect of creeping roots, awl sometimes
form thickened rootstalks, as in the Calamus and Solomon's Seal, or
tuhcrs, as in the Potato. But the type is readily seen through
these disguises. They are all mere modifications of the stem. The
leaves, as we have already seen, appear under a still greater variety
of forms, some of them as widely different from the common type of
foliage as can be imagined ; such, for example, as the thickened and
obese leaves of the Mesembryanthemums ; the intense scarlet or
crimson floral leaves of the Euchroma, or Painted-Cup, of the
Poinsettia of our conservatories, and of several Mexican Sages ; the
tendrils of the Pea tribe ; the pitchers of Sarracenia (Fig. 300),
and also those of Nepenthes (Fig. 301), which are leaf, tendril, and
pitcher combined. The leaves also appear under very different
aspects in the same individual plant, according to the purposes they
are intended to subserve. The first pair of leaves, or cotyledons,
when gorged with nutritive matter for the supply of the earliest
wants of the embryo plant, as in the Almond, Bean, Pea, &c. (Fig.
108-120), would seem to be peculiar organs. But in some of
these cases, when they have discharged this special office in ger-
mination, by yielding to the young plant the store of nourishment
with which they are laden, they imperfectly assume the color and
appearance of foliage ; while in other cases, as in the Convolvulus
(Fig. 123) and the Maple (Fig. 104), they are green and foliaceous
from the first. As the stem develops, the successive leaves vary in
form or size, according to the varying vigor of vegetation. In our
trees, we trace the last leaves of the season into bud-scales ; and in
the returning spring we may often trace the scales of opening buds
through intermediate states back again into true leaves (161).

426. The analogies of vegetation would therefore lead us to ex-
pect, that in flowering the leaves would be wrought into new forms,
to subserve peculiar purposes. In the chapter on Inflorescence, Ave
have already learned that the arrangement and situation of flowers
upon the stem conform to this idea. In this respect, flowers are
abolutely like branches. The aspect of the floral envelopes favors
the same view. We plainly discern the leaf in the calyx, and
again, more delicate and refined, in the petals. In numberless in-
stances, we find a regular transition from ordinary leaves into sepals,
and from sepals into petals. And, while even the petals are occa-
sionally green and herbaceous, the undoubted foliage sometimes
assumes a delicate texture and the brightest hues (425). The per-

ITS THKOItETICAL STRUCTURE.

227

feet gradation of leaves or bracts into sepals is extremely common.
The transition of sepals into petals is exemplified in almost every
case where there are more than two rows of floral envelopes : as in
the Magnolia, and especially in the White Water-Lily, various kinds
of Cactus, the Illicium, or Star-Anise of the Southern States, and
the Calycanthus, or Carolina Allspice, which present several series
of floral envelopes, all nearly alike in color, texture, and shape ; but
how many of the innermost are to be called petals, and how the re-
mainder are to be divided between sepals and bracts, is entirely a
matter of arbitrary opinion. In fact, the only real difference be-
tween the calyx and corolla is, that the former is the outer, and the
latter an inner series of floral envelopes. Sometimes the gradation
extends one step farther, and exhibits an evident transition of petals
into stamens ; showing that these are of the same fundamental
nature as the floi-al envelopes, which are manifestly traceable back
to leaves. The White Water-Lily (Fig. 344) exhibits this latter
transition, as evi-
dently as it does
that of sepals into
petals. Here the
petals occupy sev-
eral whorls ; and
while the exterfor
are nearly undis-
tinguishable from
the calyx, the in-
ner are reduced in-
to organs which are
neither well-formed
petals nor stamens,
but intermediate be- 344

iween the two. They are merely petals of a smaller size, with
their summits contracted and transformed into imperfect anthers,
containing a few grains of pollen : those of the series next within
are more reduced in size, and bear perfect anthers at the apex ; and
a still further reduction of the lower part of the petal completes the
transition into stamens of ordinary appearance.

427. By regular gradations, therefore, the leaf may be traced to

FIO. 344 A sepal petals, bodies intermediate between petals and stamens, and true sta-
mens, of the White Wutor-Lily.

228

THE FLOWER.

the petal and the stamen. But we could not expect to meet with
intermediate states between a stamen and a pistil, except as a mon-
strosity. The same organ could not fulfil such antagonistic offices.
Nevertheless, stamens changing into pistils are occasionally found in
monstrous blossoms. Cases of the kind are not very rare in Wil-
lows, where anthers are found either half changed or else perfectly
transformed into pistils, and bearing ovules instead of pollen. In
gardens some stamens of the common Poppy have been found
changed into perfect pistils, and imperfect attempts of the kind are
more frequently to be detected in the large Oriental Poppy. Two
Apple-trees in Ashburnham, Massachusetts, have long been known,
which annually produce flowers in which the petals are replaced by
five small foliaceous bodies, resembling sepals, and in place of sta-
mens there are ten separate and accessory pistils, inserted on the
throat of the calyx.

428. This transformation of one organ into another is called met-
amorphosis. Assuming green foliage to be the natural state of
leaves, the sepals and petals are said to be transformed or metamor-
phosed leaves ; and the stamens and pistils are still more metamor-
phosed, losing as they ordinarily do all appearance of leaves. Still,
if these organs be, as it were, leaves developed in peculiar states,
under the controlling agency of a power which has overborne the
ordinary forces of vegetation, they must always have a tendency to

343 346 develop in their primitive form, when the

causes that govern the production of blossoms
are interfered with during their formation.
They may then reverse the spell, and revert
into some organ below them in the series, as
from stamens into petals, or pass at once into
the state of ordinary leaves. That is, organs
which from their position should be stamens
g£f\X ^V^xHqA or pistils may develop as petals or floral
leaves, or else may revert at once to the state
of ordinary leaves. Such cases of retrograde
metamorphosis frequently occur in cultivated
flowers.

429. Thus we often meet with the actual reconversion of what

FIG. 345. A small leaf in place of a pistil from the centre of a flower of the double Cherry.
346. An organ intermediate between a leaf and a pistil, fiom a similar flower
FIG. 347. Leaflet of a Eryoprn Hum, developing buds along its margins.

ITS THEORETICAL STRUCTURE.

229

should be a pistil into a leaf in the double Garden Cherry, either
completely (Fig. 345), or else incompletely, so that the resulting
organ (as in Fig. 346) is something intermediate between the two.
The change of what should be stamens into petals is of common oc-
currence in what are called double and semi-double flowers of the
gardens ; as in Roses, Camellias, Carnations, &c. When such flow-
ers have many stamens, these disappear as the supernumerary petals
increase in number ; and the various bodies that may be often ob-
served, intermediate between perfect stamens (if any remain) and
the outer row of petals, — from imperfect petals, with a small lamina
tapering into a slender stalk, to those which bear a small distorted
lamina on one side and a half-formed anther on the other, — plainly
reveal the nature of the transformation that has taken place. Car-
ried a step farther, the pistils likewise disappear, to be replaced by
a rosette of petals, as in fully double Buttercups.

430. In full double Buttercups we may often notice a tendency
in the inner petals to turn
green, that is, to retro-
grade still farther into foli-
aceous organs. And there
is a monstrous state of the
Strawberry blossom, well
known in Europe, in which
all the floral organs revert
into green sepals, or imper-
fect leaves. Fig. 348 ex-
hibits a similar retrograde
metamorphosis in a flower
of the White Clover, where
the calyx, pistil, &c. are
still recognizable, although
partially transformed into
leaves. And the ovary,
which has opened down one

side, bears on each edge a number of small and imperfect leaves ;
much as the ordinary leaves, or rather leaflets, of Bryophyllum are
apt to develop rudimentary tufts of leaves, or leaf-buds, on their
margins (Fig. 347), which may grow into little plantlets, by which
the species is often propagated. This retrograde metamorphosis of

ITG. 318. A flower of the common White Clover reverting to a leafy branch j after Turpin.

20

230

THE FLOWER.

a whole blossom into foliaceous parts has been termed chlorosis, from
the green color thus assumed.

431. A somewhat different proof that the blossom is a sort of
branch, and its parts leaves, is occasionally furnished by monstrous
flowers in the production of a leafy branch from the centre of a flower,
or of one flower out of the centre of another (as rose-buds out of
roses). Here the receptacle or axis of the flower resumes the

ordinary vegetative
growth, as in Fig.
349, 350. In wet
and warm springs,
some of the flower-
buds of the Pear and
Apple are occasion-
ally forced into vege-
tation, so as com-
pletely to break up
the flower and change
it into an ordinary
leafy branch. This

349 '

proves that the recep-
tacle of a flower is of the nature of the stem.

432. An analogous kind of monstrosity, viz.
the development of buds — either into leafy
branches or into blossoms (Fig. 351) — in the
axils of petals, or even of stamens or pistils, fur-
nishes additional evidence that these bodies are

leaves j for, whatever

branch in its axil must represent a leaf.

433. The irresistible conclusion from
all such evidence is, that the flower is
one of the forms — the ultimate form —
under which branches appear ; that the
leaves of the stem, the leaves or petals
of the flower, and even the stamens
and pistils, are all forms of a common

of the nature of
bears a bud or

FIG. 349 Retrograde metamorphosis of a flower of the Fraxinella of the gardens, from
Ltndley "s Theory of Horticulture ; an internode elongated just above the stamens, and bearing
a whorl of green leaves

FIG. 350 A monstrous pear, prolonged into a leafy branch ; from Ronnet.

FIG 351. A flower ot False Hitters". cet (Celastrus scandeus), pioduciu^ other flowers in
the axils of the p-tals ; from 'I ur; in.

ITS THEORETICAL STRUCTURE. 231

type, only differing in their special development. And it mny
be added, that in an early stage of development they all appear
nearly alike. That which, under the ordinary laws of vegetation,
would have developed as a leafy branch, here developes as a flower ;
its several organs appearing under forms, some of them slightly, and
others extremely, different in aspect and in office from the foliage.
But they all have a common nature and a common origin, or, in
other words, are homologous parts (424).

434. Now, as we have no general name to comprehend all those
organs which, as foliage, bud-scales, bracts, sepals, petals, stamens,
&c, successively spring from the ascending axis or stem, having asceiv
tained their essential identity, we naturally take some one of them
as the type, and view the others as modifications or metamorphoses
of it. The leaf is the form which earliest appears, and is the most
general of all the organs of the vegetable ; it is the form which u
indispensable to normal vegetation, since in it, as we have seen, as-
similation is effected, and all organic matter is produced ; it is the
form into which all the floral organs may sometimes be traced back
by numerous gradations, and to which they are liable to revert when
flowering is disturbed and the vegetative forces again prevail.
Hence the leaf may be properly assumed as the type or pattern, to
which all the others are to be referred. When, therefore, the floral
organs are called modified or metamorphosed leaves, it is not to be
supposed that a petal has ever actually been a green leaf, and has
subsequently assumed a more delicate texture and hue, or that sta-
mens and pistils have previously existed in the state of foliage ; but
only that what is fundamentally one and the same organ develops,
in the progressive evolution of the plant, under each or any of
these various forms. When the individual organ has developed, its
destiny is fixed.

435. The theory of vegetable morphology may be expressed in
other and more hypothetical or transcendental forms. We have
preferred to enunciate it in the simplest and most general terms.
But, under whatever particular formula expressed, its adoption has
not only greatly simplified, but has thrown a flood of light over the
whole of Structural Botany, and has consequently placed the whole
logic of Systematic Botany upon a new and philosophical basis.
Our restricted limits will not allow us to trace its historical develop-
ment. Suffice it to say, that the idea of the essential identity of the
floral organs and the leaves was distinctly propounded by Lin-

232 ' TIIK FLOWER.

n$eus,* about the middle of the last century. Tt -was newly taught
by Caspar Frederic Wolff, about twenty years later, and again, after
the lapse of nearly twenty years more, by the celebrated Goethe,
who was entirely ignorant, as were his scientific contemporaries, of
what Linnaeus and "Wolff had written on the subject. Goethe's
curious and really scientific treatise was as completely forgotten or
overlooked as the significant hints of Linnaeus had been. In ad-
vance of the science of the day, and more or less encumbered with
hypothetical speculations, none of these writings appear to have ex-
erted any appreciable influence over the progress of the science,
until it had reached a point, early in the present century, when the
nearly simultaneous generalizations of several botanists, following
different clews, were leading to the same conclusions. Ignorant of
the writings of Goethe and Wolff, De Ca.ndolle was the first to de-
velop, from an independent and original point of view, the idea of
symmetry in the flower ; that' the plan, or type, of the blossom is
regular and symmetrical, but that this symmetry is more or less in-
terfered with, modified, or disguised by secondary influences, such as
suppressions, alterations, or irregularities, giving rise to the greatest
diversity of forms. The reason of the prevailing symmetrical ar-
rangement of parts in the blossom has only recently been made
apparent, in the investigation of phyllotaxis (23G) ; from which it
appears that the general arrangement of the leaves upon the stem
is carried out in the flower.

Sect. III. The Symmetrt of the Flower.

436. A Symmetrical Flower is one which has an equal number of
parts in each cirde or whorl of organs ; as, for example, in Fig.
334, where there are five sepals, five petals, five stamens, and five
pistils. It is not less symmetrical, although less simple, when there
are two or more circles of the same kind of organ ; as in Sedum
(Fig. 3G1), where there are two sets of stamens, five in each; in
the Barberry, where there are two or more sets of sepals, two of
petals, and two of stamens, three in each set, &c. A complete flower

* " Prineipium Jlorum ct foliorum idem est. Principinm p-emmarum et folio-
mm idem est. Gemma constat foliorum rudimentis Pcrianthium sit ex con-
natis foliorum rudimentis," etc. P.'tilosojthia Bolanica, p. 301.

ITS SYMMETRY.

233

(as already defined, 41 G) is one that possesses both sorts of floral
envelopes, calyx and corolla, and both essential organs, viz. stamens
and pistils.

437. The simplest possible complete and \
symmetrical flower would be one with the ca-
lyx of a single sepal, a corolla of a single petal,
a single stamen, and a single pistil ; as in the
annexed diagram (Fig. 352), which represents
the elements of a simple stem (Fig. 157), ter-
minated by an equally simple flower. Each
constituent of the blossom represents a phyton
(163), with its stem part reduced to a mini-
mum, and its leaf part developed in a peculiar
way, according to the rank it sustains and the
office it is to fulfil. That there are short inter-
nodes between consecutive organs in the flower
is usually apparent on minute inspection of its
axis, or receptacle ; and some of them are con-
spicuously prolonged in certain cases. But
they are commonly so short that the organs
are brought into juxtaposition, just as in a leaf-
bud, and the higher or later-formed parts are
interior or enclosed by the lower.

438. Perhaps the exact case of a flower at
once so complete and so simple is not to be met
with, the organs of the flower, or some of
them, being generally multiplied. Thus we
And a circle or whorl of each kind of organ,
and often two or three circles, or a still larger
and apparently indefinite number of parts. In
fact, the floral organs usually occur in twos,
threes, fours, or fives ; and the same number
is apt to prevail throughout the several circles
of the flower, which therefore displays a sym-
metrical arrangement, or a manifest tendency towards

* Terms expressive of the number of parts which compose each whorl ot
kind of organ — which are sometimes very convenient to use — arc formed of

FIG 352 Diagram of a plant, with a distichous arrangement of the phvtons. carried
through the complete flower, of the simplest kind, consisting of, a, a sepal ; i, a petal ; c, a
stamen ; and rf, a pistil : br is the bract or uppermost proper leaf.

20*

234

THE FLOWER.

439. Having already noticed the symmetrical arrangement of the
foliage (236-251), and remarked the transition of ordinary leaves
rf into those of the blossom

(42G),we naturally seek
to bring the two under
the same general laws,
and look upon each floral
whorl as answering ei-
ther to a cycle of alter-
nate leaves with their m
respective intemodes undeveloped,
or to a pair or verticil of opposite
or verticillate leaves. Thus, the simplest com-
bination, where the organs are dimerous, or in
two 3, may be compared with the alternate two-
ranked arrangement (238), the calyx, the corolla,
stamens, &c. each consisting of one cycle of two
elements ; or else with the case of opposite leaves
(250), when each set would answer to a pair of
leaves. So, likewise, the organs of a trimerous
flower (viz. one with its parts in threes, as in Fig.
353) may be taken either as cycles of alternate
334 leaves of the tristichous mode (239), with the axis
shortened, which would throw the parts into successive whorls of
threes, or else as proper verticils of three leaves ; while those of a
pentamerous or quinary flower (with the parts in fives, as in Fig. 354)
would answer to the cycles of the \ arrangement (240) of alternate
leaves, or to proper five-leaved verticils. So the whorls of a tetra-
merous flower are to be compared with the case of decussating op-

thc Greek numerals combined with jue'po?, a part. Thus a flower with only one
organ of each kind, as in the diagram, Fig. 352, is monomerous : a flower or a
whorl of two organs is dimerous (Fig 373) ; of three (as in Fig 353), trimeious;
of four, Mramerous (Fig. 405) ; of five (as in Fig. 334), pentamerous; of six, hex-
amerous ; of ten, decamerous, &c. These words are often printed with figures, as
2-merous, 3-merOus, i-merous, 5-merous, and so on.

FIG. 353. Parts of a symmetrical trimerous flower (Tilloea museosa) : a, calyx ; 6, corolla ;
e, stamens ; d. pistils

F!G. 334 Ideal plan of a plant, with the simple stem terminated by a symmetrical penta-
merous flower ; the different sets of organs separated to some distance from each other, to show
the relative situation of the parts j one of each, namely, a, a sepal, b, a petal, c, a stamen, and
d, a pistil, also shown, enl irged.

ALTERNATION OF THE FLORAL ORGANS. 235

posite leaves, combined two by two, or with quaternary vertieillate
leaves (251) ; either of which would give sets of parts in fours.

440. The Alternation of the Floral Organs. We learn from obser-
vation that, as a general rule, the parts of the successive circles of
the flower alternate with each other. The five

petals of the flower represented in Fig. 334, for ex-
ample, are not opposed to the five sepals (that is, if//' q^
situated directly above or before them), but alter-
nate with them, that is, or stand over the intervals
between them ; the five stamens in like manner al-
ternate with the petals, and the five pistils with the
stamens, as is shown in the diagram, Fig. 335. The same is the
case in Fig. 353, the several organs of a flower with its parts in
threes ; and in fact this is the rule, the few exceptions to which
have to be separately accounted for.

441. This comports with the more usual phyllotaxis in opposite
and verticillate leaves, where the successive pairs decussate, or cross
each other at right angles (251), or the leaves of one verticil several-
ly correspond to the intervals of that underneath, making twice as
many vertical ranks as there are parts in the whorl. The alternation
of the floral organs is therefore most readily explained on the assump-
tion that the several circles are true decussating verticils. But the
inspection of a flower-bad with the parts imbricated in aestivation
(494) shows that the several members of the same set do not origi-
nate exactly in the same plane. The five petals, for example, in
the cross-section of the pentamerous blossom shown in Fig. 335 (and
the same arrangement is still more frequently seen in the calyx),
are so situated, that two are exterior in the bud, and therefore in-
serted lower on the axis than the rest, the third is intermediate, and
two others are entirely interior, or inserted higher than the rest. In
fact, they exactly correspond with a cycle of alternate leaves of the
quincuncial or five-ranked arrangement, on an extremely abbreviated
axis, or on a horizontal plane, as is at once seen by comparing the
ground plan, Fig. 335, with Fig. 206. Compare also Fig. 355 with
Fig. 203. Aho, when the parts are in fours, two are almost always
exterior in the bud, and two interior. Moreover, whenever the
floral envelopes, or the stamens or pistils, are more numerous, so as
to occupy several rows, the spiral disposition is the more manifest.
It is most natural, accordingly, to assume that the calyx, corolla,

FIG. 355. Cross-section of the Howcr-bud of Fig 353, to show the ulteruutiou of yurti.

236 THE FJ-OWETl.

stamens, &c. of a pentamerons flower are each a depressed spiral or
cycle of the § mode of phyllotaxis, and those of the trimerous flower
are similar spirals of the £ mode. But then the parts of the suc-
cessive cycles should be superposed, or pi ;ced directly before each
other on the depressed axis, as leaves are ; whereas, on the contrary,
they almost always alternate with each other in the flower.

442. To reconcile this alternation with the laws of phyllotaxis in
alternate leaves, Prof. Adrien de Jussieu has advanced an ingenious
hypothesis. He assumes the -fc spiral arrangement as the basis of
the floral structure both of the trimerous and pentamerous flower,
(at least when the envelopes are imbricated in the bud,) this being
the one that brings the successive parts most nearly into alternation,
either in threes or in fives ; as will readily be observed on inspection
of the tabular projection of that mode, given on page 139. The dif-
ference between the position of parts in regular alternation, whether
in threes or fives, and that assigned by an accurate spiral projection
of the T5j mode, is very slight as respects most of the organs, and in
none does the deviation exceed one thirteenth of the circumference ;
— a quantity which becomes nearly insignificant on an axis so small
as that of most flowers. Moreover, if the interior organs of a regular
and symmetrical flower were thus to originate in the bud nearly in
alternation with those that precede them, they would almost necessa-
rily be crowded a little, as they develop, into the position of least pres-
sure, and thus fall into these intervals with all the exactness that is
actually found in nature. For in living bodies, endowed as they are
with plasticity and a certain power of adaptation to circumstances,
the positions assumed are not mathematically accurate ; and the
effect of unequal pressure in the bud in throwing the smaller parts
more or less out of their normal position may be observed in almost
any irregular flower. Moreover, in all the forms of phyllotaxis
from T5j onwards, it is doubtful whether what we term vertical ranks
are exactly superposed. In tracing them upward to some extent,
we perceive indications of a curviserial arrangement, where the
superposition is continually approximated, but is never exactly at-
tained (248). Lestibudois* has revived the older hypothesis of
Jussieu, and others ; viz. that a second spiral is introduced with the
petals and continued in the pistils. Ana" Schimper and Braun im-
agine a change of half the angular divergence {prosenthesis) to occur

* In Annates des Sciences Naturellcs, scr. 4, Vol. 2, p. 226.

POSITION IN RESPECT TO TIIK BRACT AM) AXIS.

237

in passing from one cycle to the next ; — which is rather describing
the anomaly in other words than explaining it.

443. Whether we regard the floral circles as decussating verticils,
or as cycles of alternate leaves in some way altered as to their suc-
cession, we cannot fail to discern an end attained by such arrange-
ment, namely, a disposition of parts which secures the greatest econ-
omy of space on an abbreviated axis, and the greatest freedom from
mutual pressure.

444. Position of the Flower as respects the Axis and subtending Bract.

All axillary flowers are situated between a leaf and the stem, or,
which is the same thing, between a bract, and the axis of inflores-
cence. These two fixed points enable us to indicate the relative
position of the parts of the floral circles with precision. That part
of the flower Which lies next the leaf or bract from whose axil it
arises is said to be anterior, or inferior (lower) : that which is dia-
metrically opposite or next the axis is posterior, or superior (upper).*

It is important to notice the relative position of parts in this re-
spect. This is shown in a proper diagram by drawing a section
of the bract in its true position under the section of the flower-
bud, as in Fig. 358 : the position of the axis is necessarily dia-
metrically opposite, and its section is sometimes indicated by a dot
or small circle. In an axillary flower with the parts in fours, one of

* As if these were not terms enough, sometimes the organ, or side of the
flower, which looks towards the bract, is likewise called exterior, and the organ
or side next the axis, interior ; but these terms should be kept to designate the
relative position of the members of the floral circles in aestivation (494).

FIG. 356. Diagram of a Cruciferous flower (Erysimum); i
bract is abortive in this, as in most plants of this family.)

FIG. 357 Diagram of a flower of a Rhus, with the axis
relative position of parts.

FIG. 358. Diagram of a flower of the Pulse tribe : a, the I

, the axis of inflorescence. (The
a, aud the bract, 6, to show the
xis, aud t), the bract

238 TIIK FLOWER.

the sepals will be anterior, one posterior, and two lateral, or right
and left ; as in the annexed diagram of a Cruciferous blossom (Fig.
356) ; while the petals, alternating with the sepals, consist of an
anterior and a posterior pair ; and the stamens, again, stand before
the sepals. An axillary flower of five parts will have either one
sepal superior or posterior and two inferior or anterior (as in Rhus,
Fig. 357), or else, vice versa, one inferior and two superior, as in
Papilionaceous flowers (Fig. 358) : in both cases the two remaining
sepals are lateral. The petals will consequently stand one superior,
two inferior, and two lateral, in the last-named case ; and one in-
ferior, two superior, and two lateral, in the former. In terminal
flowers (401), the position of parts in respect to the uppermost
leaves or bracts should be noted.

Sect. IV. The Various Modifications of the Flower.

445. The complete and symmetrical flowers, with all their organs
in the most normal state, that have now been considered, will serve
as the type or pattern, with which we may compare the almost num-
berless variety of forms which blossoms exhibit, and note the char-
acter of the differences observed. We proceed upon the supposi-
tion, that all flowers are formed upon a common plan, — a plan
essentially the same as that of the stem or branch, of which the
flower is a modified continuation, — so that in the flower we are to
expect no organs other than those that, whatever their form and
office, answer either to the axis or to the leaves ; so that the differ-
ences between one flower and another are to be explained as cir-
cumstantial variations of one fundamental plan, — variations for the
most part analogous to those which occur in the organs of vegeta-
tion themselves. Having assumed the type which represents our
conception of the most complete, and at the same time the simplest
flower, we apply it to all the cases which present themselves, and
especially to those blossoms in which the structure and symmetry
a.e masked or obscured; where, like the disenchanting spear of
Ithuriel, its application at once reveals the real character of the most
disguised and complicated forms of structure.

446. Our pattern flower consists of four circles, one of each kind of
floral organ, and of an equal number of parts, successively alternat-
ing with one another. It is complete, having both calyx and corolla,

ITS VARIOUS MODIFICATIONS. 239

as well as stamens and pistils (41 6) ; symmetrical, having an equal
number of parts in the successive whorls (436) ; regular, in having
the different members of each circle all alike in size and shape ; it
has but one circle of the same kind of organs ; and, moreover, all the
parts are distinct or unconnected, so as to exhibit their separate
origin from the axis or receptacle of the flower. This type may be
presented under either of the four numerical forms which have been
illustrated. That is, its circles may consist of parts in twos (when
it is binary or dimerous), threes (ternary or trimerous), fours {qua-
ternary or tetramerous), or fives (quinary or pentamerous). The
first of these is the least common ; the trimerous and the pentame-
rous far the most so. The last is restricted to Dicotyledonous plants,
where five is the prevailing number ; while the trimerous flower
largely prevails in Monocotyledonous plants, although by no means
wanting in the Dicotyledonous class, from which Fig. 353 is taken.

447. The principal deviations from the perfectly normal or
pattern flower may be classified as follows. They arise, either
from, —

1st. The production of additional circles of one or more of the
floral organs (regular multiplication or augmentation) ;

2d. The production of a pair or a cluster of organs where there
should normally be but one, that is, the multiplication of an organ
by division (abnormal multiplication, also termed deduplication or
chorisis) ;

3d. The anteposition (or opposition, instead of alternation) of the
parts of successive circles ;

4th. The union of the members of the same circle (coalescence) ;

5th. The union of adjacent parts of different circles (adnation) ;

6th. The unequal growth or unequal union of different parts of
the same circle (irregularity) ; or,

7th. The non-production or abortion of some parts of a circle, or
of one or more complete circles (suppression or abortion).

8th. To which may be added, the abnormal development of the
receptacle or axis of the flower.

448. Some of these deviations interfere with the symmetrical
structure of the flower ; others merely render it irregular, or dis-
guise the real origin or the real number of parts. These deviations,
moreover, are seldom single ; but two, three, or more of the kinds fre-
quently co-exist, so as to realize almost every conceivable variation.

449. Several of these kinds of deviation may often be observed

240

TIIK PLOTTER.

even in the same natural family of plants, where it cannot be doubt-
ed that the blossoms are constructed upon a common plan in all the
species. Even in the family Crassulacea>, for example, where the
flowers are remarkably symmetrical, and from
which our pattern flowers, Fig. 334 and 353,
are derived, a considerable number of these di-
versities are to be met with. In Crassula, Ave
have the completely symmetrical and simple
pentamerous flower (Fig. 359, 3C0), viz. with a
calyx of five sepals, a corolla of five petals alter-
nate with the former, an andrcccium (418) of
five stamens alternating with the petals, and a
gynaecium (419) of five pistils, which are alter-
nate with the stamens ; and all the parts are
regular and symmetrical, and also distinct and
free from each other ; except that the sepals are
somewhat united at the base, and the petals and
330 stamens slightly connected with the inside of the

calyx, instead of arising directly from the recep-
tacle or axis, just beneath the pistils. Five is the prevailing or
normal number in this family. Nevertheless, in the related genus
Tillrea, most of the species, like ours of the United States, have
their parts in fours, but are otherwise similar, and one common
European species has its parts in threes (Fig. 353) ; that is, one or
two members are left out of each circle, which of course does not in-
terfere with the symmetry of the blossom. So in the more conspic-
uous genus Sedum (the Stoneerop, Live-for-ever, Orpine, &c), some
species have their parts in fives ; others
in fours ; and several, like our S. ter-
natum, have those of the first blossom
in fives, but all the rest in fours. But
Sedum also illustrates the case of reg-
ular augmentation (447, 1st) in its an-
droccium, which consists of twice as
many stamens as there are members
in the other parts ; that is, an addi-
tional circle of stamens is introduced (Fig. 3C>1), the members of
which may be distinguished by being shorter or a little later than

FIG 359 Flower of a Crassula. 3H0 Cross-section of the bud.
FJG. 361 Flower of a Seduui or Stoneerop.

ITS VARIOUS MODIFICATIONS.

241

those of the primary circle, and hy their alternation with tho<oy
which brings them directly opposite the petals. A third genus
(Roehea) exhibits the same pentamerous and normal flower as Cra-
sula, except that the contiguous edges of the petals slightly cohere
about half their length, although a little force suffices to separate
them : in another (Grammanthes, Fig. 3G2), the petals are firmly
united into a tube for more than half their length, and so are the
sepals likewise ; illustrating the fourth of the deviations above
enumerated (447). Next, the allied genus Cotyledon (Fig. 3G3)
exhibits in the same flower both this coalescence of similar parts,
and an additional circle of stamens, as in Sedum. It likewise pre-
sents the next order of deviations, in the union (adnation) of the
base of its stamens to the base of the corolla, out of which they ap-
parently arise, as is seen in Fig. 3G4, where the corolla is laid open
and displayed. The pistils, although ordinarily exhibiting a strong
tendency to unite, are perfectly distinct in all these cases, and in-
deed throughout the order, with two exceptions ; one of which is
seen in Penthorum, where the five ovaries (Fig. 365) are united
below into a solid body, while their summits, as well as the styles,
are separate. The same plant also furnishes an example of the non-
prorluction (or suppression) of one set of organs, that of the petals ;
which, although said to exist in some specimens, are ordinarily want-
ing altogether. Another instance of increase in the number of parts
occurs in the Houseleek (Sempervivum), in which the sepals, petals,
and pistils vary in different species from six to twenty, and the sta-
mens from twelve to forty.

362 363 3S4

4o0. Some illustrations of the principal diversities of the flower,

FIG 352 Flower of Grammanthes. 353 Flower of a Cotyledon 361 The eoiolln laid
open showing the two rnws of stamens inserted iuto it. 365 The five pistils of Penthorum,
united. 336. A eross-section of t'.ie same

21

242 tiik rr.OAvr.u.

as classified above (447), may be drawn at random from different
families of plants ; and most of the technical terms necessarily em-
ployed in describing these modifications may be introduced, and
explained, as we proceed. The multiplication of parts is usually in
consequence of the

451. Augmentation of the Floral Circles. An increased number of
circles or parts of all the floral organs occurs in the Magnolia
family ; where the floral envelopes occupy three or four rows, of
three leaves in each, to be divided between the calyx and corolla,
while the stamens and pistils are very numerous, and compactly
arranged on the elongated receptacle. The Custard-Apple family,
which is much like the last, has also two circles in the corolla, three
petals in each, a great increase in the number of stamens, and, in
our Papaw (Fig. 654), sometimes only one circle of pistils, viz.
three, sometimes twice, thrice, or as many as five times that number.
The Water-Lily, likewise, has all its parts augmented, the floral
envelopes and the stamens especially occupying a great number of
rows ; and the pistils are likewise numerous, although their number
is disguised by being united into one body. When the sepals, petals,
or other parts of the flower are too numerous to be readily counted,
or even exceed twelve, especially when the number is inconstant, as
it commonly is in such cases, they are said to be indefinite ; and
a flower with numerous stamens is also termed polyandrous.

452. When such multiplication of the floral circles is perfectly
regular, the number of the organs so increased is a multiple of that
which forms the basis of the flower ; but this could scarcely be de-
termined when the numbers are large, as in the stamens of a Butter-
cup, for example, nor is there much constancy when the whorls of
any organ exceed three or four. The doubling or trebling of any
or all the floral circles does not interfere with the symmetry of the
flower ; but it may obscure it (in the stamens and pistils especially),
by the crowding of two or more circles of five members into what
appears like one of ten, or two trimerous circles into what appears
like one of six. The latter case occurs in most Endogenous plants.

453. The production of additional floral circles may account for
most cases of increase of the normal number of organs, but not for
all of them. It must, we think, be admitted that certain parts of the
blossom are sometimes increased in number by the production of a
double organ, or a pair or a. group of organs which occupy the place
tf one ; namely, by what luu been termed

C1IOHISIS Oil DKfoL'PLICATIOK.

213

454. CllOl'isis or Dcilliplication. Tlie name dedonblement of Dunal,
which has been translated dediiplication, literally means unlimng ;
the original hypothesis being, that the organs in question imline, or
tend to separate into two or more layers, each having the same
structure. We may employ the word deduplication, in the sense
of the doubling or multiplication of the number of parts, without
adopting this hypothesis as *o the nature of the process, which at
best can well apply only to some special cases. The word chorisis
(xaipttm, the act or state of separation or multiplication), also pro-
posed by Dunal, does not involve any such assumption, and is ac-
cordingly to be preferred. By regular multiplication, therefore, we
mean the augmentation of the numbe? of organs through the de-
velopment of additional circles ; which ^oes not alter the symmetry
of the flower. By chorisis we denote the production of two or more
organs in the place of one, in a maimer analogous to the division of
the blade of a leaf into a number of separate blades, or leaflets.

455. Chorisis, or the division of an organ into a 367
pair or a cluster, may take place in two ways.
In one case the parts or organs thus produced
stand one before the other ; in the other case they
stand side by side. The first is named transverse
chorisis ; the second, collateral e/iorisis. Both
must evidently disturb or disguise the normal
symmetry of the blossom.

456. Collateral Chorisis is that in respect to

which there is least doubt as to the nature of the

process. We have a good example of it in the

te.tradynamous stamens (519) of the Mustard or

Cress family (Fig. 406). Here, in a flower with

a symmetrical tetramerous calyx and corolla, we

have six stamens ; of which the two lateral or

shorter ones are alternate with the adjacent

petals, as they normally should be, while the four

are in two pairs, one pair before each remaining interval of the

petals ; as is shown in the annexed diagram (Fig. 367). That is,.

on the anterior and on the posterior side of the flower we have two

stamens where there normally should be but a single one, and where,

FIG. 357 Diagram of a (tetradynamous) flower of the order Cruciferoe.
FIG. 303. Flower of Streptanthus bjacintlioidcs, from Texas (the sepals and stamens re-
moved), showing a forked or double stamen in place of the anterior pair.

244

Tin: FLOW'KR.

indeed, there is but one in a few plants of this family. Now it oc-
casionally happens that the doubling of this stamen is, as it were,

arrested before com-
pletion, so that in
place of two stamens
we have a forked fila-
ment bearing a pair
of anthers ; as fre-
quently happens in
some species of Strep-
tanthus (Fig. 368).

in place of one may
be compared with a
compound leaf of two
leaflets. In the re-
lated Fumitory fam-
ily three stamens reg-
ularly appear in the
place of one. The
circles of the flower
are in twos through-
out ; viz. there is,

first, a pair of small scale-like sepals ; alternate with these, a pair

of petals, which, in Dicentra, &c. (Fig. 3CJ-371), are saccate or

spurred below ; alternate and within these

is a second pair of petals (Fig. 372) ;

alternate with these are two clusters of

three more or less united stamens, which

plainly occupy the place of two single

stamens. The arrangement of parts is

shown in the annexed diagram (Fig.

373) ; where the lowest line indicates the 371

subtending bract, and therefore the anterior side of the blossom -,

the two short lines in the same plane represent the sepals ; the two

FIG 3G9 Dicentra Cucullaria (Rutchman's-Breeches), with its kind of bulb, a leaf, and a
gcape in flower ; reduced in size 370 A flower of tlie natural size. 371 The same, with the
parts separaied, except the sepals, one of which is seen at the base of the pistil. 372 The
inner pair of petals, with" their tips coherent.

FIG 373 Diagram (cross-section) of the similar flower of Adlumia 374 One of the sta-
mens increased into three by chorUis (the lo.ver u irt of the conunoa filament is cut away).

CIIOIIISIS OH DEDUPLTCATION.

245

next within, the lateral and exterior petals ; those alternate and
within these, the inner circle of petals ; and alternate with these are
the anthers of the two stamen-clusters. The centre is occupied hy
a section of the pistil, which consists of two united. The three sta-
mens arc lightly connected in Dicentra (Fig. 371) ; hut in Corydalis
and Adlumia th'ire is only one strap-shaped filament on each side,
which is three-forked at the tip, each fork hearing an anther (Fig.
374). We have a .similar case in some Hypericums and in Elodea
(Fig. 375), except that, while the floral envelopes are in fives, the
circles within them are commonly in
threes. The three memhers of the
androccium are normally placed, alter-
nating with the three memhers of the
gynaicium within, and also with three
glands, which probably replace another
circle of stamens. Now each real
stamen is here multiplied into three,

united below ; so that the whole compound body may be viewed as
homologous with a compound trifoliolate leaf (289). If this be so,
then each cluster of numerous stamens in the common St. Johns-
wort may be regarded as answering to one stamen greatly multiplied
in the same way, and as analogous to a sessile decompound leaf.
And the same maybe said of each stamen-cluster in the Linden
(Fig. 383). The actual development of the cluster, from a protu-
berance which in the forming flower-bud occupies the place of a
single stamen, has been traced by Duchatre, Payer, &c. in this and
other cases.

457. Thus far Ave are sustained by a clear analogy in the organs
of vegetation. As the leaf frequently develops in the
form of a lobed, divided, or compound leaf, — that is, as
a cluster of partially or completely distinct organs from
a common base, — so may the stamen, or even the pistil,
become compound as it grows, and give rise to a clus-
ter, instead of completing its growth as a solitary organ :
and it appears that the organogeny is strikingly sim-
ilar in the two cases. Nor is it very unusual for petals to become
divided or deeply lobed in the same manner ; as, for example, those

FIG 375. Diagram (cross-section) of a flower of Elodea Virginica. 376 One of the turea
Btamen-cl asters, consisting of a trebled stamen, enlarged.
1'IG. 377 A petal ol Mignoiu-tto. inlaiged.
21*

246

THK FLOWl'.R.

of Mignonette (Fig. 877). In certain cares an analogous division
takes place in the opposite direction, ?o that the parts or lobes are
situated one before the other. An indication of this is also mani-
fest in the petals of Mignonette, the lower part or broad claw
of which is slightly extended at its summit, on each side, beyond
the origin of the many-cleft limb or blade. Division in this direc-
tion has been termed

458. Transverse or Vertical Chorisis. The most familiar case is that
of the crown, or small and mostly two-lobcd ap-
pendage on the inside of the blade of the petals
of Silene (Fig. 378) and of many other Caryo-
phyllaceous plants. This is more like a case of
real dedoublement or vnlining, i. c. a partial sepa-
ration of an inner lamella from the outer, and
perhaps may be so viewed. Stamens sometimes
bear a similar and more striking appendage, as
in Larrea, for example (Fig. 379), and most
other plants of the Guaiacum family ; also in the 3:8

Dodder (Fig. 1044). Let it be noted that in all such
cases the appendage occupies the inner side of
or stamen, and that it is commonly two-lobed
before each petal of Parnassia (Fig. 381), although
slightly if at all united with it, is found a body which in
P. palustris is somewhat petal-like, with a considerable
number of lobes, and in P. Caroliniana is divided almost
379 to the base into three lobes, which look much like abortive
stamens. The true stam-
ineal circle, however, oc-
cupies its proper place
within these ambiguous
bodies, alternate with 'the
petals. We cannot doubt
that the former are of the
same -nature as the scale
of the stamens in Larrea,
and the crown of the petals

le petal

Again,

FIG S78 A petal of Silene Pennsylvaniea, with its crown or appendage.

FIG. 379 A stamen of Larrea Mexicana, with a scale-like appendage cohering with its base
on the inner 6ide

FIG 380 Diagram (cross-section) of the flower of Paroa&sia Caroliniana. 381. A petal,
with the appendage that standd befoic it.

CHORISIS OR DEDUM.ICATION. 247

of Silene ; and we incline to consider the accessory body in such
eases as homologous* with the stipules of the leaf*

459. It may also be noticed, that, while in collateral chorisis the
increased parts are usually all of the same nature, like so many
similar leaflets of a compound leaf, in what is called transverse cho-
risis there is seldom such a division into homogeneous parts ; but the
original organ remains, as it were, intact, while it bears an append-
age of some different appearance or function on its inner face, or
at its base on that side. Thus the stamens of Larrea, &c. bear

* For fuller illustrations of these theoretical points, the stiulent is referred to
the figures and text of The Genera of i lie United States F.'oia Illushafed, espe-
cially to Vol. 2. — An able writer in Hooker's Journal of Botany andKew Garden
Miscellany, Vol. 1, p 3G0, (with whom we aie in accord as to the nature of col-
lateral chorisis,) "being totally at a loss to find anything analogous in the
ordinary stem-leaves" to this transvcise or vertical multiplication of parts, in-
clines to consider such appendages as those of the petals of Silene, Sapindus,
Ranunculus, &c. as deformed glands, and the stamens thus situated, whether
singly or in clusters, as developments of new parts in the axil of the petals, &c.
It appears to us, however, that the leaves do furnish the pioper analogue of
such appendages as those of Fig. 378-381, and the similar petaloid scales of
Sapindaceas, Erythroxylcse, and the like, in the Ugule of Grasses, and the stip-
ules. The former occupies exactly the same position. The latter form an-
essential part of the leaf, and usually develop in a plane parallel with that of
the blade, but between it and the axis ; particularly when they arc of consider-
able size, and serve as teguments of the bud, as, for example, in Magnolia (Fig.
156). The combined intrapetiolar stipules of Mclianthus furnish a case in
point, to be compared with the two-lobed internal scale of the stamens in Lar-
rea, the two-cleft adnatc appendage of the petals in Caryophyllcai, Sapindus,
&c. ; and instances of cleft or appendaged stipules may readily be adduced to
show that such bodies arc as prone to multiplication by division as other foliar
parts. The supposition of a true axillary origin of the organs in question,
therefore, appears to be gratuitous, and it would certainly introduce needless
complexity into the theory of the flower. Nor docs it throw any light upon
their morphology to call such appendages of petals " deformed glands " ; a term
which is much too vague to have any assignable morphological value. In
Linum true stipules arc reduced to glands. At present, therefore, wc think that
the same general name may properly enough be employed both for the collateral
and the vertical multiplication of organs, where two or more bodies occupy the
place of one, carefully distinguishing, however, the two different cases. Some
special term is needful for discriminating between such multiplication and that
by the regular augmentation of floral organs through the development of addi-
tional circles, and none the less so, because wc rcrornizc, in one or both kinds
of chorisis, modes of division which arc common to the floral organs and to the
foliage.

248

TIIF FLOWF.K.

a scale-like appendage ; the petals of Sapindus, Cardiospermum,
&c, a petaloid scale quite unlike the original petal ; the petals of
Parnassia, a cluster of bodies resembling .sterile filaments united
below.

460. TIl8 Alltcposition or superposition of parts which normally
alternate in the flower has in some cases been regarded as a case of
transverse chorisis ; but it is susceptible of a simpler explanation.
The principal case that occurs is that of the stamens, or the outer-
most circle of stamens, being placed directly before the petals

(in ordinary botanical lan-
guage opposite the petals).
The Vine (Fig. 384- 38G)
and the Buckthorn families
are good examples of this
anomaly, as also is Clay-
tonia in the Purslane fam-
ily. And in Linden and
many of its allies a cluster of stamens (Fig. 382, 383) stands be-
fore each petal, the American Lindens 334 3S5
having also a petal-like scale in the
centre of every cluster. The clusters
must be viewed as multiplications of
single stamens by collateral chorisis.
The position of the stamens before
the petals in these cases, as well as
that of the numerous petals in certain
double Camellias, arranged through-
out in five vertical ranks, is most
readily explained by supposing a re-
turn to the regular -f or five-ranked
phyllotaxis of leaves (240). 386

461. In the genuine Geranium (Fig. 421) the position of the outer
of the two sets of stamens before the petals evidently results
from the abortion of an exterior circle (486) ; and perhaps this is
the case in the Primrose family also. In the Parberry family there
is an apparent anteposition of the sepals, petals, and stamens through-

n a cross-section of the bud.

FIG 332. Diagram of the (lower rf the American Lin
383. A cluster of stamens with the petal-like body in the middle.

FIG. 384. Flower of the Grape, casting its petals before expansion,
out the petals : both show the glands distinctly, within the stamens
Uower.

The same, with-
. Diagram of th«

COALKSCKNCE OF ITS PARTS. 249

out. But this arises from the symmetrical augmentation of each set
of organs into two circles, which in the expanded flower appear like
one. In the flower-bud of the Barberry the calyx is seen to consist
of two alternating circles of sepals, three in each ; the corolla, of two
circles of petals, three in each ; the three exterior petals alternating
as they should with the inner circle of sepals, and the three interior
ones alternating with these. But when the flower opens, the six
petals, spreading apparently as one whorl, are necessarily opposed
to the six sepals ; and the six stamens in two circles, which are still
more confluent into one whorl, are equally opposed to these, taken six
and six ; although they really alternate in circles of three. In other
words, decussating verticils of threes necessarily form six vertical
ranks (251, 441). It is just the same in the Lily, Crocus, and most
Monocotyledonous plants ; where the perianth is composed of six
similar leaves in two circles, and the androccium of six stamens in
two circles, giving a regular alternation in threes ; although, when
taken by the casual observer as composed of two circles of six, it
gives the appearance of six stamens before as many petals.

462. The Coalescence or union of the parts of the same whorl or
set of organs is so frequent,, that few cases are to be found in which
it does not occur, to a greater or less extent, in some portion of the
flower. When the sepals are thus united into a cup or tube, the
calyx is said to be monosepcdous, or, more correctly, gamosepalous ;
when the petals are united, the corolla is said to be monopetulous, or
yamopetalous. The latter is the appropriate term, as it denotes
that the petals are combined ; but the former is in common use, al-
though etymologically incorrect, as implying that the corolla consists
of a single petal. The current names, in these cases, were given
long before the; structure was rightly understood. So, also, such a
calyx or coiolla is said to be- entire, when the sepals or petals are
united to their very summits ; or to be toothed, lobed, cleft, or parted,
according to the degree in which the union is incomplete ; this lan-
guage being employed just as in the case of the division of leaves
(281). On the other hand, when the sepals are not united, the calyx
is said to be polysepalous ; and when the petals are distinct, the
corolla is said to be polypetalous ; that is, composed of several
petals.

463. The union of the stamens with each other may occur either
by their filaments, as in the Pea and most of the Pulse family, or by
their anthers, as in the Sunflower and the whole Composite family, or

2j0

THE FLOWER.

by both the filaments and the anthers, as in Lobelia and the Gourd.
An account of the modes of such union, and of the terms employed
to express them, may be found in Section VI. The union of the
pistils is still more common than that of stamens, and is illustrated in
Section VII.

4G4. The terms union, cohesion, and the like, must not be under-
stood to imply that the organs in question were first formed as
distinct parts, and subsequently cohered. This is seldom the case.
The union is congenital ; the members of a gamosepalous calyx, a
gamopetalous corolla, &c. showed their union from the earliest
period. The language we use has reference to our idea of these
parts, as answering each to a single leaf. We might more cor-
rectly say that the several leaves of the same circle have failed to
isolate themselves as they grew. The same remark applies to the
analogous case of

4G5. Adnatioil, or Consolidation, the union of different circles of
floral organs with one another. This may take place in various de-
grees. It presents the appearance of one circle or set of parts grow-
ing out of another, as the corolla out of the calyx, the stamens out of
the corolla, or all of them out of the pistil ; and therefore disguises
the real origin of the floral organs from the receptacle or axis, in
successive series, one Avithin or above the other (421). The con-
sideration of the flower as respects such consolidation, or its ab-
sence, gives rise to three terms which are much used in descrip-
tive botany, and which the student should thoroughly understand,
viz. hypogynous, perigynous, and epigynous.

4G6. The first of these
terms applies to the case in
which there is no adnation or
consolidation of unlike parts.
That is, when the calyx,
corolla, and stamens are
borne (i. e. inserted) on the
receptacle, they are said to
be hypogynous (from two
Greek words meaning under
the pistil), as in Buttercup, Flax (Fig. 387), &c. The floral organs
in such cases are also said to be free ; which is the term opposed to

FIG 387 Vertical section of a flower of the Common Flax, showing the normal or hypo-
gjuous insertion of parts.

CONSOLIDATION OH ADNATION.

25 L

the adhesion of one organ to another, as that of distinct is to the
cohesion of the parts of the same whorl or set of organs. Thus, the
stamens are said to be distinct, when not united with each other, and
to ha free, when they contract no adhesion to the petals, sepals, or
pistils ; and the same language is equally applied to all the floral
organs. The word connate (born united) is applied either to the
congenital union of homogeneous parts (as when we say that the two
leaves of the upper pairs of the Honeysuckle are connate, Fig. 294,
the sepals or stamens are connate into a tube, or the pistils into a
compound pistil), or to the coalescence of heterogeneous parts (as
that of the petals with the calyx, or of both with the pistil). But
the word adnate belongs to the latter case only.

467. "When such consolidation takes place, and the petals and
stamens (which almost always accompany each other), or either of
them, are inserted on the
calyx, i. e. are adnate with
the base of the calyx (as in
the Cherry, Fig. 388, or
Purslane, Fig. 389), they are
said to be perigynous (liter-
ally, placed around the pis-
til). The real origin of the
parts must be the same as in
the former case, that is, the
parts really belong to the re-
ceptacle, in successive circles,
one above or within the other,
first the sepals, then the pet-
als, within these the stamens,
and within or above these
the pistils ; but the true origin
or position of some of the parts is here obscured by the adnation, at
their base at least, of parts which are normally separate. In Fig.
388, the petals and stamens are adnate to the lower part of the
calyx, but all are free from the pistil. But in Fig. 389, all four
organs are consolidated below, as far as to the middle of the
ovary.

FIG. 388. Vertical section of a flower of the Cherry, to show the perigynous insertion of
the petals and stamens.

FIG 389 Similar section of the flower of the Purslane, showing an adnation of parts with
the lower part of the ovcry

232

THK FLOWER.

468. Iii llie Apple, Hawthorn (Fig. 390), and many other plant?,
the consolidation extends farther, and the calyx is adnate to, i. e.

invests and coheres with the
whole surface of the ovary,
which accordingly appears
to he under the rest of the
flower, instead of the upper-
most and innermost part, as
it properly is. The earlier
botanists called the flower,
or calyx, in such cases, supe-
rior, and the ovary and fruit
inferior ; and when no such consolidation occurs, the flower, or
calyx, ece. was said to he inferior, and the ovary superior. But
these terms should he superseded hy the equivalent and much more
appropriate expressions of calyx adherent, in the one case, and calyx
free, in the other ; or hy that of ovary coherent with the calyx, and
ovary free from the calyx, which is the same thing in other words.*
More commonly the corolla and the stamens, are adnate to the
calyx beyond where these parts all separate from the pistil ; in which
case they are still periyynous, or borne on the calyx. In some
such cases, as in the Evening Primrose and Fuchsia, the tube of
the calyx is prolonged far beyond the ovary, and the petals and
stamens are inserted oh it just below where it separates into its
distinct lobes.

4G9. In other flowers the petals and the stamens are distinct at
the line where the calyx separates from the top of the ovary, or are
borne on the edge or face of a thickened disc (489) which crowns its
summit, as in Aralia (Fig. 410), the Ivy, and all that family, in the
whole Parsley family, the Cornel family, the Cranberry (Fig. 391),
and the like. The stamens, &c, being then apparently borne on the
ovary, are said to be cpiyynous (from two Greek words meaning
"on the pistil").

* A favoiitc view at present is that the calyx in many cases (as in the Rose,
Apple, &e ) actually begins at the place where it is distinct from the parts with-
in, and that the so-called tube is the summit of the peduncle hollowed out, or
developed around the pistils. This view can be correct in certain cases only,
and the difference between it and the current view is really not so great as it
seems.

FIG. 390. Flower of Hawthorn vertically divided, to show the calyx adnate to the ovary.

ITS IRREGULARITY.

203

470. In some few plants the stamens continue this adnation a little
further, and cohere with the style, either with its bate only, as in
some species of Asarum,orwithits

whole length, as in Cypripedium
(Fig. 468) and the whole Orchis
family. Then the flower is said
to be gynandrous ; — from two
Greek words equivalent in mean-
ing to stamens and pistil com-
bined (519).

471. Irregularity. The flower

is irregular when the parts of its
different circles, or of one or

more of them, are not all alike in number,
shape, or size. Irregularity may be the re-
sult, therefore, either of the abortion or dis-
appearance of some parts, or of their tin-
equal development or unequal ration. The
latter case may be first considered.

472. The Pea tribe affords a familiar
illustration of irregidar flowers arising from
the unequal size and dissimilar
form of the floral envelopes ;
especially of the corolla, which,
from a fancied resemblance to a
butterfly in the flower of the
Pea, Locust (Fig. 392), &c, has
been called papilionaceous. The
petals of such a corolla are dis-
tinguished by separate names ;
the upper one, which is usually
most conspicuous, being termed
the vexilhtni, standard, or banner
(Fig. 392', a); the two lateral
(b) are called wings (alee), and
the two lower (c), which are
usually somewhat united along their anterior edges, and together

FIG 391. Flower of Cranberry divided lengthwise, showing the petals and stamens epi-
gynous

FIG. 302 Front view of a flower of the common Locust-tree (Uobiuia r-seudacacia).

FIG 892'. Corolla of the same, the petals displayed.

2",4

THK l'LOWXU.

form a body in shape resembling the keel, or rather the narrow
prow, of an ancient vessel, are named the carina or keel. The calyx
of the same blossom is slightly irregular by the unequal union of
parts, the two upper sepals being united higher than the other three.
In Baptisia these two sepals are coalescent to the tip, or nearly id,

causing the calyx to ap-
pear as if formed of four
sepals instead of five In
most Lupines, not only are
the two upper sepals coa-
lescent into one body near-
ly or quite to the tip, but
the three remaining ones
are likewise united into
one body, on the lower side
of the flower, thus giving
the calyx the appearance
of consisting of two petals
in place of five. The ir-
regularity of papilionaceous flowers likewise affects the stamens,
which, although of symmetrical number, 396

viz. ten, or two circles, are in most cases
unequally coalescent, nine of them being
united by the cohesion of their filaments
for the greater part of their length,
while the tenth (the posterior) stamen
is distinct ; as is illustrated in the sec-
tion on the stamens (518). But in
Amorpha (Fig. 395), which belongs to
the same tribe of plants, the ten stamens
are united' barely at their base; and
there is a complete return to regularity
in those of Baptisia (Fig. 394) and
Sophora, which are perfectly distinct or
separate. The Violet (Fig. 397) offers
another very familiar form of irregu-
lar flowers ; the irregularity belonging

391.

FIG. 393. Papilionaceous flower of Baptisia
show iug the ten distinct stamens.

FIG. 395. Flower of Amorpha 395'. The same
the slightly monadelphous stamens

FIO 396 Flovcr ot A iola sagittate. 397 Its re

The same, with the petals removed,
h the solitary petal removed, showing
and petals di-pla; cd

SUITRKSSION Oil ABORTION OF TARTS. 2")0

mainly to the corolla, the lower petal of which is prolonged back-
ward into a sac or spur. The Larkspur and Monkshood (Fig. 398-
402) are irregular hoth in the calyx and the corolla, not oidy by a
diversity in the size and shape of homologous parts, but also by the
suppression of some of them. We may therefore consider them
under the next head.

473. Of irregular monopetalous flowers the most common form is
the bilabiate or tico-lipped, as in the corolla of the Sage, Snap-
dragon, and most of the large families to which they belong (Fig.
4G0) : this, like the calyx of the Lupine, described above, arises
from the unequal union of the parts. The same is the case with
the two-lipped corolla of the "Woodbine and other Honeysuckles,
only here, instead of two lobes or petals forming the upper lip and
three the lower, four petals enter into the composition of the upper
lip, leaving only one for the lower (Fig. 861). The Trumpet
Honeysuckle returns nearly to regularity again, the whole five
petals being coalescent into a tube to near the top, leaving an al-
most equally five-lobed border. The corollas of Germander (Fig.
996) and of Lobelia (Fig. 902) are further irregular by a want of
union on the upper side of the blossom: and the liyulate or open
and strap-shaped corolla of Coreopsis (Fig. 325, c) and other Com-
posite evidently answers to such a regular monopetalous corolla as
a, split down on one side and outspread.

474. Suppression or Abortion, that is, the complete or the partial
obliteration of some member, is a common cause of irregularity.
The term suppression is used when parts which belong to the plan
of the blossom do not actually appear in it. The term abortion is
applied not only to such disappearance, but to partial obliteration,
as where a stamen is reduced to a naked filament, or to a mere rudi-
ment or vestige, answering to a stamen and occupying the place
of one, but incapable of performing its office. Such obliteration,
whether partial or complete, may affect either a whole circle of
organs or merely fome of its members. The former interferes with
the completeness of a flower, and may obscure the normal order of
its parts. The latter directly interferes with the symmetry of the
blossom, and may be first considered.

475. Suppression of some Parts of a Circle of Organs. The Larkspur

and Aconite or Monkshood furnish good examples of flowers which
are both irregular and symmetrical. The calyx of the Larkspur
(Fig. 398, 399) is irregular by rea.on of the dissimilarity of the five

25G

T 1 1 IC FLOWER.

sepals, one of which, the uppermost and largest, is prolonged poste-
riorly into a long and hollow spur. Within these, and alternate with

them as far as the)' go, are the petals, only four in numher, and these
of two shapes, the two upper ones having long spurs which are re-

FIG. 898 Flower of a Larkspur. 399 The five sepals (outer circle) and the four petals
(inner circle) displayed. 400 Ground-plan of the calyx and corolla

FIG 401 Flower of an Aconite or Monkshood 402 Tile five sepals and the two small
and curiously-shaped petals displayed : also the stamens and pistils in the centre 403.
Ground-plan of the calyx and corolla; the dotted lin.s, as in Fig 400, representing the sup-
pressed parts.

SCITRFSSION OR ABORTION' OF PA1STS.

257

ceivcd into the spur of the upper sepal ; the two lateral ones having
a small but broad blade raised on a stalk-like claw ; and the place
which the fifth and lower petal should occupy (marked in the ground
plan, Fig. 400, by a short dotted line) is vacant, this petal being sup-
pressed, thereby rendering the blossom unsymmetrical. In Aconite,
(Fig. 401, 402) the plan of the blossom is the same, but the upper-
most and largest of the five dissimilar sepals forms a helmet-shaped or
hood-like body ; and as to the petals, three are wanting altogether
(their places are shown by the dotted lines in the ground plan, Fig.
403) ; the two upper ones, which extend under the hood, only re-
main, and these are so reduced in size and so anomalous
in shape that they would not ordinarily be recognized as
petals. One of them enlarged is exhibited in Fig. 404.
Petals, &e. of this and other extraordinary forms were
termed by Lhnueus Nectaries, an unmeaning or mislead-
ing name, as they are no more likely to secrete honey
than ordinary petals are.

476. The papilionaceous corolla (472)
becomes strikingly unsymmetrical by
suppression in Amorpha (Fig. 395).
Here the corolla is uniformly reduced to
a solitary petal (the standard), the other
four petals being totally obliterated.
This obliteration is foreshadowed in Ery-
thrina herbacea of the Southern States, and oilier
species, in which all the petals except the standard
are small and inconspicuous. "While the blossom
of the common Ilorsechestnut, although irregular,
is symmetrical, so far as respects the calyx and
corolla, that of our nearly related Buckeyes gener-
ally wants one of the five petals, a vacant place on
the anterior side of the flower indicating its absence.

477. The suppression or abortion of some of the
stamens requisite to the symmetry of the blossom is
According to the ordinary view, the six stamens of

the flowers of the Mustard family (Fig. 403, 406), where the sepals
and petals arc in fours, is explained by supposing that, out of two
circles of stamens, four in each, two stamens of the outer circle are

very common.

riO 404 One of the petals of an Aconite or Monkshood, enlarged.

FIG. 405. Flower of Mustard 403 Its six stameus and the pistil, enlarged.

22*

2-38

THE FLOWER.

suppressed. But wc incline to the opinion that this port of flow or
is rendered unsymmetrical, not by the suppression of two short sta-
mens, but by the chorisis or division of the two stamens each into a
pair (456, Fig. 368).

478. Most flowers which are irregular by the unequal union of
407 the petals, especially tho e with a bi-

labiate corolla (473, 511), are likewise
unsymmetrical by the abortion of one
or more of the stamens. In the Cat-
nip, Balm, &c, and in the Snapdragon,
Monkey-flower, Foxglove, and the
like, as aho in Gerardia (Fig. 407),
where the corolla is only slightly ir-
regular, four stamens occupy their
proper places alternate with its lobes,
but the fifth stamen is altogether want-
ing. In its place, however, the corolla
of the Figwort, belonging to the same
family as the Snapdragon and Ge-
rardia, bears a small scale, and that of
Chelone and Pentstemon (Fig. 408)
bears an antherless filament, which,
from its position, must be the wanting
stamen, in an abortive state ; and in
one species it has actually been found
with a perfect or an imperfect anther,
completing the symmetry of the flow-
er. The four perfect stamens in these
cases are of unequal length, two of
them being longer than the other two
(i. e. they are didynamous, 520).
The two shorter stamens also disappear in many such plants, as in
Gratiola or Hedge-Hyssop", — rometimes leaving vestiges in their
place, and sometimes not ; also in Sage, Horse-Mint, and the like.
Here three stamens out of five are suppressed. So they commonly

FIG 407 Corolla of Gerardia purpurea laid open, with the four stamens the place which,
the fifth should occupy indicated by ac:a?s

FIG. 408 Corolla of Pentstemon giai.diflorus laid open, with its four stamens, and a sterile
filament in the place of the fifth st:imcn

FIG. 400 Corolla of Catalpa iJ.i open, with, two perfect stamens and the vestiges of throe
abortive ones.

SUPPRKSSIOX OR ABORTION OK TARTS. 2.39

are in the blossom of Catalpa (Fig. 409), hut their vestiges remain
in the form of small sterile filaments, two of which, however, occa-
sionally hear anthers, either perfect or rudimentary.

479. The suppression of a portion of the pistils required to com-
plete the symmetry of the flower is exceedingly common. The
tendency to obliteration, seems to increase as we advance towards
the centre of the blossom, owing, douhtless, to the greater pressure
exerted on the central parts of the hud, and the progressively di-
minished space the organs have to occupy on the conical receptacle.
Thus, while the corolla, when present at all, almost always consists
of as many leaves as the calyx, the members of the stamineal circle
or circles are frequently fewer in number, and the pistils are still
more commonly fewer, excepting where the axis is prolonged for
the reception of numerous spiral cycles. Thus, the pistils, which
present the symmetrical number in Sedum, and all plants of that
family (Fig. 334, 33o, 3*55, 361), are reduced to two, or rarely three,
in the allied Saxifrage family, while the other floral circles are in
five*. So, in the Wild Sarsaparilla (Fig. 410) and Spikenard, the
flowers are pentamerous throughout, although the ovaries of the five
pistils are united into one ; but they are reduced to three in the
Ground-nut, and to two in the Ginseng, belonging to the same genus,
as also in all Umbelliferous plants. Although the pistils are in-
definitely augmented in the Rose, Strawberry, and the greater part
of Rosaceous plants, or are of the normal number five in Spiraea,
yet there are only two in Agrimonia, one or rarely two in Sangui-
torba, and uniformly one in the Plum and Cherry (Fig. 388),
although the flowers of the whole order are formed on the pentame-
rous, or sometimes the tetramerous plan, and with a strong tendency
to augmentation of all the organs. And the Pulse family has, almost
without exception, five members in its floral envelopes, and ten, or
two circles, in its stamens, but only a single pistil (Fig. 358).

480. Suppression of one or more whole Circles. A complete flower,

as already remarked (41G), comprises four whorls or sets of organs;
namely, calyx, corolla, stamens, and pistils. When any of these four
circles or kiiids of organs are wanting, the flower is said to be in-
complete. The non-production of any one or more of the whorls is
not uncommon. The calyx, however, is seldom if ever wanting
when the corolla is present, or rather, when the floral envelopes con-
sist of only one whorl of leaves, they are called calyx, whatever be
their appearance, texture, or color, unless it can somehow be shown

260

THE FLOWER.

that an outer circle is suppressed.* Tor since the calyx is fre-
quently delicate and petal-like (in botanical language petahid or
colored), and the corolla sometimes greenish
or leaf-like, the only real difference between
the two is, that the calyx represents the
outer, and the corolla the inner series ; and
even this distinction becomes more or less
arbitrary when either, or both, of these or-
gans consist of more than one circle. The
apparent obliteration of the calyx in some
cases is owing to the entire cohesion of the
tube with the ovary, and the reduction of the free portion, or limb,
to an obscure ring or border, either slightly toothed or entire, as in
Aralia (Fig. 410), Fedia (Fig. 882), Cornus, the fertile flowers of
Nyssa, &c. In Composite, the partially obliterated limb of the
calyx, when present at all, cons^ts of scales, teeth, bristles, or a
ring of slender hairs (as in the Thistle), and receives the name of
pappus.

481. The petals, however, are frequently absent ; when the flower
is said to be apetalous, as in the Anemone (Fig. 411), Clematis,
Caltha, &c, in the Crowfoot family,
other genera of which are furnished
with both calyx and corolla ; and as
in some species of Buckthorn, while
others have manifest although small
petals. They are constantly wanting
in a large number of families of Ex-
ogenous plants, which on this account
form the division Apetalce. When
the calyx is present while the corolla
is wanting, the flower is said to be

monochlamydeous, that is, with a perianth (417) or floral envelope of
only one kind ; as in the cases above mentioned.

* In our Northern Zanthoxylum the inonochlamydcous peiianth which is
present may, however, he justly held to he the corolla, and not the calyx, he-
cause the five stamens alternate with it, just as they do with the undoubted
petals of Z Caiolinianum : in this case, therefore, we may say that the calyx,
and not the corolla, is suppressed. See Genera Illustiata, Vol. 2, p 148, tab 156.

FIG 410. Flower of Aralia nudiraulis, vertically divided : the limb of the calyx obsolete.
FIG. ill. Huner of Anemoue L'e&ntfj lvuuica ; apetaious, thecal) x. peculoid.

SUPPRESSION OR ARORTION OK PARTS.

2G1

482. In some flowers, moreover, as in the Lizard's-tail (Fig. 412),
both the calyx and the corolla are entirely wanting, and the blossom
is achlamydeons, i. e. destitute of any perianth
or floral envelopes whatever. Having the es-
sential organs, viz. the stamens and pistils, how-
ever, this flower also is perfect (hermaphrodite,
or bisexual), although incomplete.

483. The abortion of all
the stamens or all the pis-
tils of a flower is common
enough, as well in flowers that have as in
those that have not complete floral envelopes ;
but whenever either of these essential organs
are abortive or wanting in some blossoms, they
are present in others of the same species,
either on the same or on different individuals.
Flowers of this kind having stamens only or
^-^^V^y pistils only are said to be separated, diclinous,

or unisexual. And the flower which has the
stamens but no pistils, or only imperfect ones, is said to be staminate,
sterile, or male ; while
that provided with
pistils, but with no
stamens, or only im-
perfect ones, is pis-
tillate, fertile, or fe-
male. Not to multi-
ply examples, in Smi-
lax and in Menisper-
mum(Fig. 413, 414)
we have good instan-
ces of separated flow-
ers in which the ahor-
tion is confined to the
stamens or the pistils,
the floral envelopes
being present and

FIG 412 Flower of Lizard's-tail (Saururus cernuus), magnified.

FIG 413 A staminate flower of Menispermum or Moonseed. 414. A pistillate flower of
the same The latter lias six abortive stamens : the former, mere vestiges of pistils

FIG 415. A catkin of staminate flowers of Salix alba. 416. A single staminate flower de-
tached aud enlarged (the bract turned from t.us eje) 41T. A pistillate cutkiu of the same
species 41S A detached pistillate flower, maguined.

2G2 THIi FLOWER.

complete. And in the "Willow (Fig. 415-418) we have separated
flowers extremely simplified by abortion. The flowers are crowded in
catkins, each one in the axil of a bract : the staminate flowers consist
of a few stamens merely, in this species of only two ( Fig. 4 1 G), and the
pistillate, of a pistil merely (Fig. 418). That is, the flowers are wholly
destitute of calyx and corolla (unless a little glandular scale on the
upper side should be a rudimentary perianth of a single piece), and
in one set of blossoms the stamens are also suppressed ; in another,
the pistils. The stamens vary in number in different species, from
two to five. If there were only one of the latter, an instance would
be afforded of flowers reduced, not merely to one kind of organ, but to
a single member. Now. there is one species of "Willow, which ap-
pears to have its sterile blossoms reduced to a solitary stamen. It
has therefore been named Salix monandra. But on in-
spection this seemingly single stamen is found to consist
of two united with each other quite to the top (Fig.
419). Here, a? in many other cases, the normal condi-
tion of the flower is not only much altered by the sup-
pression of mo;t of the organs, but disguised by the coa-
lescence of thoe that remain.

484. In separated flowers the two kinds of blossoms
may be borne either upon different parts of the same
individual, or upon entirely different individuals. The flowers are
said to be monoecious when both kinds are borne on the same plant;
as in Indian Corn, the Birch, the Oak, Beech, Hazel, Hickory, &c. :
and they are called dioecious when borne by different individuals ; as
in the "Willow and Poplar, the Sassafras, the Prickly Ash, the Hemp
and Hop, Moonseed (Fig. 413, 414), &c. Occasionally, while ^ome
of the flowers are staminate only, and others pistillate only, a por-
tion are perfect, the different kinds occurring either on the same or
different individuals ; as in most Palms, in many species of Maple,
&c. : plants with such flowers are said to be polygamous.

4S5. In some of the blossoms of certain plants both stamens and
pistils are wanting. This is the case with those that occupy the
margin of the cymes of the Hobblebush and some other Viburnums,
and of Hydrangea (Fig. 420), or even with the whole cluster in
cultivated monstrous states, as in the Snowball or Guelder-Rose
of the gardens (Viburnum Opulus). Here the enlarged corollas

FIO 419 A staminate flower of Salix purpurea (or monandra), with the stamens coaleseent
(monadelplious and syngenesious), so as to appear like a single oue.

suppression on aboktion ok parts.

2G3

make the whole blossom. Such flowers, being neither staminate
nor pistillate, are said to be neutral. In so-called compound flowers
(394) the strap-shaped marginal flowers are sometimes neutral, as
in Coreopsis (Fig. 324, 32o), Mayweed, and Sunflower. In some
Grasses and other plants such neutral flowers want the floral en-
velopes also, or are reduced to an abortive rudiment.

48C. The suppression or abortion of a whole circle of organs in a
symmetrical flower does not destroy its symmetry, if we take, note
of the absent members. Thus a monochlamydeous flower, with a
single full circle of stamens, usually has the latter placed opposite
the leaves of the perianth, that is, of the calyx, the corolla or in-
tervening circle having failed to appear. But when, with the abor-
tion of the primary circle, say of the stamens, we have an augmenta-
tion of one or more additional circles of the same; kind of organ, the
law of alternation appeal's to be violated ; the stamens that are
present, or the outer circle of them, standing before the petals, in-
stead of alternate with them. It is customary to assume this ex-
planation for all eases of tin; anleposition of the stamens to the pet-
als, whether in the Primrose family, in Claytonia, in the Vine (Fig.

FIG 420. Cyme of Hydrangea arborescens, with the large marginal llowers neutral

2G4

THE FLOWER.

384), or the Buckthorn, &c. But more probable explanations for
some su-.'Ii cases have already been given (4o9, 4G0). It can no
longer be deemed sufficient to assume the obliteration of a normal
floral circle, and the production of a second one, when no traces of
the former can be detected and no clear analogy shown with some
strictly parallel instance. Yet we may confidently apply this view
when we do find traces of obliterated organs, as in the Geranium
family, for example. The pentamerous flower of Geranium exhibits
ten stamens, plainly occupying two rows, the five of the exterior
circle shorter than the others. One set of these stamens alternates
with the petals, the other is opposed to them. But on close exami-
nation, we perceive that it is the inne7- circle of stamens that alter-
nates with the petals ; those of the outer circle stand directly before
them. This is a not uncommon case where there are just twice as
many stamens as there are petals or sepals. In this instance the
explanation of the anomaly is furnished by
the five little bodies, called by the vague and
convenient name of glands, which stand on
the receptacle between the petals and the sta-
mens, and regularly alternate with the former.
They accordingly occupy the exact position
of the original stamineal circle: wherefore, as
4;I situation is the best indication of the nature of

organs, we may regard them as the abortive rudiments of the five
proper stamens, here obliterated. In the. annexed diagram (Fig. 421)
these are accordingly laid down in the third circle, as five small oval
spots, slightly shaded. The actual stamens consequently belong to
Uvo augmented circles, those of the exterior and shorter set of which
(represented by the larger, unshaded figures), normally alternating
with the glands, are of course opposed to the petals, and thoe of the
inner and larger set, normally alternating with the preceding, neces-
sarily alternate with the petals. This view is further elucidated by
the closely allied genus Erodium, where all the parts are just the
same, except that the five exterior actual stamens are shorter still,
and are destitute of anthers ; that is, the disposition to suppression,
which has caused the obliteration of the primary circle of stamens
and somewhat reduced the second in Geranium, has in Erodium

FTC 421 Diagram (cross-section! of the flower of Geranium macnlntum, exliitiitino; the
relative position of parts, especially the gland* alternate with the petals, and the two rows ot
stamens within theui.

SUPPRESSION OR ARORTION OK PARTS. 265

rendered the latter abortive also, leaving those of the third row alone
to fulfil their proper olfice. And in a South African genus, Mon.so-
nia, five stamens actually occur in the place of these glands, making
fifteen real stamens, or three circles. The general plan of the flower
is the same in the Flax family, except that the glands winch answer
to the outer rank of stamens are still
less conspicuous, and those of the next
circle are reduced to small abortive
filaments, or to minute teeth in the
ring formed by the union of all the
filaments into a cup at the base, leav-
ing five perfect stamens, which, though

they alternate with the petals indeed, belong to a third circle (Fig.
422, 423). In a few species of Flax, this second circle of stamens
is perfectly obliterated, so that no vestige is to be seen.

487. The complete suppression of two or three of the circles be-
longing to the complete flower, and of a part of the members of what
remains, reduces a blossom to the last degree of simplicity. Among
the simplest of perfect flowers are those of Callitriche (Fig. 1136 —
1138), which have neither calyx nor corolla ; and only one stamen,
as is expressed in the annexed diagram (Fig. 424) ; yet the four-

lobed pistil show 3
that the blossom was

constructed on the

d

o plan of four. And

424 ^ — Ti 1 ^ — T'j r even this stamen is

suppressed in cer-
tain blossoms, and the pistil in others. In Euphorbia (also to be
illustrated under the family to which it belongs, Fig. 1143) the
flowers are always separated, and the staminate blossom is reduced to
a single stamen, the pistillate to a single three-lobed pistil (Fig. 425).
And in the Willow, as already noticed (433y, the pair of stamens
which represents one sort of blossom, and the single pistil which repre-
sents the other, are widely separated, being borne on distinct trees.

FIG. 422. Flower of Linum perenne 423 Its stamens and pistils enlarged.

FIG 424. Diagram of a perfect flower of Callitriche, with eo floral envelopes, one stamen,
and a four-celled pistil

FIG 425 Diagram of the monoecious flowers of Euphorbia: a, the pistillate flower re-
duced to a mere three-celled pistil ; and i, one of the staniiuate flowers reduced to a single
stamen.

FIG 426. Diagram of the dioecious flowers of the Willow : a, one of the pistillate flowers
reduced to a solitary pistil , 6, a stamiuato flower reduced to a pair of stamens.

23

A

0

TIIK FLOWER.

4S8. Unusual Slates cf the Receptacle. The receptacle (421) is
commonly small, short, and inconspicuous, being merely the extrem-
ity of the flower-stalk upon which the sev-
eral organs are inserted (Fig. 343). Some-
times, however, it is remarkably enlarged
or elongated. A striking instance of an en-
V v -O O J^l larged receptacle is found in Nelumbium,
where it is dilated into a large top-shaped
body, nearly enclosing the pistils in sep-
arate cavities (Fig. 427). Whenever the
pistils of a flower are very numerous, the
receptacle is more or less enlarged for their
insertion, as in Magnolia, the Raspberry and Blackberry, &c.
In the Strawberry the enlarged and conical
receptacle (Fig. 428), bearing the pistils on
its surface, becomes the edible portion in
fruit. In the Rose (Fig.
429) the receptacle is
deeply concave, instead
of convex, being urn-
shaped, invested by the
adnate tube of the calyx,
and bearing the petals
and stamens on its bor-
der and the numerous
pistils on its whole hol-
low surface (Fig. 429).
It is much the same in
Calycanfhus(Fig.814-
819). In Geranium, and m

many allied plants, the receptacle is prolonged between the ovaries,
and coheres with their styles (Fig. 430) ; these, however, separating
at maturity (Fig. 431). In Umbelliferous plants a similar but more
slender prolongation of the receptacle is extended upwards between
the contiguous faces of the two united ovaries which form the fruit

HO. 427. The enlarged, top-shaped receptacle of Nelumbium, bearing the pistils, im-
mersed in hollows of its upper face.

FIG 428. Longitudinal section of a young strawberry, enlarged.

FIG. 429 Similar section of a young Rose-hip

FIG. 430 Gynaccium of Geranium maculatum, or Cranesbill, enlarged.

FIG 431. The same at maturity, with the five pistils splitting away from the long beak or
receptacle and hanging from its top by their styles.

TIIK RECEPTACLE, DISK, ETC.

267

in that family. Occasionally one or more of the internodes between
successive floral circles elongate ; as between the calyx and the
corolla in Pinks, and especially in Silene, forming a stalk within the
calyx, on which the rest of the flower is raised (Fig. 432) ; while
in many Gentians the inter-
node above the circle of
stamens is developed, rais-
ing the pod on a stalk of its
own. This is a common
case in the Caper family ;
in which the genus Gynan-
dropsis (Fig. 433) exhibits
a remarkable development
of the whole receptacle. It
is enlarged into a flattened
disk, where it bears the pet-
als, and is then prolonged 4S2
into a conspicuous stalk which bears the stamens, — or rather, to
which the bases of the stamens are adnate, — and then into a shorter
and more slender stalk for the pistil ; thus sepai-ating the four circles
or sets of organs, like so many whorls of verticillate leaves. The
general name for this kind of stalk, as contradistinguished from the
pedicel or stalk of the flower, is the Stipe ; and whatever organ or
set of organs is thus elevated is said to be stipitate. Whenever it is
necessary to particularize the portion of the receptacle thus devel-
oped, the stipe is termed the Anthophore when it appears just above
the calyx, and elevates the petals, stamens, and pis-
tils ; the Gonophore, when it supports both the sta-
mens and pistils ; and the Gynophore, Gynobase, or
Carpophore, when it bears the gynaecium alone. The
stalk which sometimes supports each simple pistil of the
gynsecium (as in Coptis or the Goldthread) is called
a Thecaphore. This, however, does not belong to the
receptacle at all, but to the pistil itself, and is ho-
mologous with the leafstalk. m

489. A Disk is a part of the receptacle, or a growth from it, en-
larged under or around the pistil. Like the other parts of the flower,

FIG. 432. Section of a Tower of Silene Pennsylvania, showing the stipe or anthopho
FIG. 433. Flower of Gynandropsis, with a remarkably elongated receptacle.
FIG. 434. Disk of the Orange, unde neath the pistil (Irtpugynous)

2GS TIIK FLOWER.

it \i hypogynons (4GG), when free from all union either with the pis-
til or the calyx, as in the Rue and the Orange (Fig. 434). It is
perigynous (4G7), when it adheres to the base of the calyx, as

in the Buckthorn (Fig. 43o,
436) ; and where the calyx is
adnate to the ovary, as in the
Apple, Hawthorn (Fig. 390),
&c, there is commonly a disk in-
terposed between the two. The
435 m disk is sometimes expanded on

the summit of such an ovary, when it is said to he epigynous (4G9),
as in Cornus, and all Umbelliferous plants.

Sect. V. The Floral Envelopes ix Particular.

490. Their Development, or Organogeny, first requires a brief notice.
The flower-bud is formed in the same Avay as the leaf-bud ; and
what has been stated as to the formation of the leaves of the branch
(273) equally applies to the leaves of the flower. The sepals are
necessarily the earliest to appear, which they do in the form of so
many cellular protuberances, at first distinct, inasmuch as then their
tips only are eliminated from the axis. Each one may complete its
development separately, like an ordinary leaf, when the sepals re-
main distinct. Or the lower and later-eliminated portions of the
forming organs of the circle coalesce as they grow into a ring, which,
further developed in union, forms the cup or tube of the gamophyl-
lous calyx. In some case/, it would appear that the sepals may at
first grow separately, and afterwards, though only at a very early
period, coalesce by the cohesion of their contiguous parts. The sev-
eral parts of an irregular calyx are at first equal and similar ; the
irregularity appears in their subsequent unequal growth. The pet-
als or parts of the corolla originate in the same way, a little later
than the sepals. Their coalescence in the gamopetalous corolla is
congenital ; the ring which forms its tube appearing nearly as early
as do the slight projections which become its lobes and answer to the
summits of the component petals. The rudiments of the petals are
visible earlier than those of the stamens : but their growth is at first

FIG 435. Flower of a Buckthorn, showing a large perigynous disk 43G. Vertical section
of the same.

JESTIVATIOX OR PIUKFLORATION. 2C9

retarded, so that the stamens are earlier completed, and their
anthers surpass them, or often finish their growth, while the petals
are still minute scales : at length they make a rapid growth, and
enclose the organs that belong above or within them. Unlike the
sepals in this respect, the base of the petal is frequently narrowed
into a portion which corresponds, more or less evidently, to the
petiole (the claw), and which, like the petiole, does not appear until
some time after the blade or expanded part ; the summit being al-
ways the earliest and the base the latest portion formed. As the
envelopes of the flower grow and expand, those of each circle adapt
themselves to each other in various ways, and acquire the relative
positions which they occupy in the flower-bud. Their arrangement
in this state is termed

491. Their ^Estivation or Prrcfloralioii. The latter would be the

preferable term ; but the former is in common use ; the word ^Esti-
vation (literally the summer state) having been devised for the
purpose by Linnojus; — for no obvious reason except that he had
already applied the name of Vernation (the spring state) to express
the analogous manner in which leaves are disposed in the leaf-bud.
The same terms are employed, and in nearly the same way, in the
two cases, but with some peculiarities. As to the dis*?rr:t"cn of
each leaf taken by itself, the corresponding terms of vernation (257)
wholly apply to aestivation The arrangement in the bud of the
several members of the same floral circle in respect to each other, is
of much importance in systematic botany, on account of the nearly
constant characters that it furnishes, and also in structural botany,
from the aid it often affords in determining the true relative super-
position or succession of parts on the axis of the flower, by observ-
ing the order in which they overlie or envelope each other.

492. The various forms of aestivation that have been distinguished
by botanists may be reduced to three essential kinds, namely, the
imbricative, the contorted or convolutive, and the valvular*

493. Imbricative aestivation, in a general sense, comprises all
the modes of disposition in which some members of a floral circle
are exterior to the others, and therefore overlie or enclose them in

* Wo should properly say of tho (estivation that it is imbt iratioe, convolutive,
valvular, Sec, and of the calyx and corolla, or of the sepals, &c., that they are
imbricate or imbricated, convolute, va/vate, &c. i:i Aestivation ; but such precision
of laniruain; is seldom attended to.

270

TIIK FLOWER.

the bud. This must almost necessarily occur wherever the parts"
are inserted at distinguishably different heights, and is the natural
result of a spiral arrangement. The name is most significant when
successive leaves are only partially covered by the preceding, as in
Fig. 207. Here they manifestly break joints, or are disposed like
tiles or shingles on a roof, as the term imbricated denotes. It is
therefore equivalent to the spiral arrangement : and, on the other
hand, we properly apply the term imbricated to any continuous
succession of such partly overlying members ; as when we say of
appressed and crowded leaves that they are imbricated on the stem,
or thus express the whole arrangement of the scales of a bud
(Fig. 153), or a bulb (Fig. 172), or of a catkin or cone (Fig. 209).
The alternation of the petals with the sepals, &c. necessarily
renders the floral envelopes likewise imbricated in the bud, taken as
a whole. But in proper aestivation, what we have to designate is
the arrangement of the parts of the same floral circle (say the five
sepals or the five petals) in respect to each oilier.

494. Now when the sepals or
the petals are three in number,
and are regularly imbricated in
the bud, as in Fig. 437, the three
leaves are arranged just as in
three-ranked phyllotaxis (238,
Fig. 203) ; that is, with the first
lie second is covered by the first on
one side while it covers the third o:i the other. When they are five
(as in the calyx of Geranium, Fig. 439), they are disposed just as in
five-ranked or quincuncial phyllotaxis with the
axis shortened (240, Fig. 206) ; viz. two leaves
are exterior, two wholly interior, and one (the
third) with one edge covered by No. 1 on one
side while it covers No. 5 with its oilier edge. So
that this, the regular mode of imbrication when
the parts are in fives, is termed quincuncial aes-
tivation, or the parts are said to be quincuncially

petal exterior to the others, th

FIG 437. Diagram of a three-leaved (trimerous) calyx and corolla, both Imbricated in
aestivation.

FIG 438 Diagram of tne estivation of three petals (or one circle of the petals) of Magno-
lia, similarly imbricated, but strongly enwrapping, each making nearly a circle

FIG 439 Diagram of the imbricativo aestivation of the calyx and the convolutive aestiva-
tion of the corolla of Geranium ; the sepals numbered.

AESTIVATION OR PRAKFLOKATION. 271

imbricated. We have here the advantage of being able to number
the successive sepals, or petals, since the third leaf is not only recog-
nizable by its intermediate position, but also indicates the direction
in which the spiral turns (Fig. 20G and Fig. 439).

495. It must be recollected, in the comparison, that the parts of
successive cycles are superposed in the foliage, while those of the
floral circles alternate. Regular imbrication in the 4-merous flower
gives two outer and two inner members in aestivation (as in the
calyx of Cruciferous blossoms, Fig. 3G7), on the principle of two
decussating pairs of leaves (441) ; or it may sometimes be refer-
able to a modification of some alternate spiral arrangement.

496. The degree of overlapping depends upon the breadth of the
parts and the slate of the bud ; it naturally grows less and loss as
the bud expands and is ready to open. It, is from the full-grown
flower-bud, just before anthesis (or the opening of the blossom), that
our diagrams are usually taken ; in which the parts are represented
as moderately or slightly overlapping. The eame overlapping car-
ried to a greater extent will cause the outer leaf to envelope all the
rest, and each succeeding one to envelop those within ; as shown in
Fig. 438 from one circle of petals of a Magnolia taken in an early
state of the hud. To this, however, has not improperly been applied
the name of convolute, from its similarity to the convolute vernation
of the leaves of the branch (257), similarly rolled up one within the
other. But it is practically inconvenient, and wrong in principle, to
designate different degrees of the very same mode by distinct names ;
fjrthcrmore, it is to the next general mode of aestivation that the
name of convolute is more commonly applied, at least in recent sys-
tematic botanical writings.

497. There are numerous cases cf imbricative aestivation, espe-
cially in irregular flowers, where the overlapping of parts does not
altogether accord with what must needs be their order of succes-
sion on the axis. In the 5-merous calyx and corolla of all truly
papilionaceous flowers, foi* example, one edge of the sepal or the
petal No. 2 is placed under, instead of over, the adjacent edge of
No. 4, in consequence of which three, instead of only one, of the
leaves have one edge covered and the other external ; as is shown
in Fig. 358. Since, in the corolla of this kind of blossom, the ex-
terior petal, here the vexillum (472), is the larger, and at first em-
braces all the rest, this modification of imbricative; aestivation has
received the name of vexillary. Ai nearly the same thing occurs

272

THE FLOWER.

in the Violet, it is probably caused by some slight dislocation that
takes place during the early growth of organs in the irregular blos-
som. It is not restricted to irregular flowers, however, but occurs
as a casual variation, or perhaps more frequent-
ly than the quincuncial, in the regular corolla
of the Linden (as is shown in Fig. 440). A
slight obliquity in the position of the petal No.
2, assumed at an early period, would account
for the whole anomaly. That this suggests
the true explanation is almost demonstrated by
440 the varying aestivation of the corolla of the

Linden ; in which the same bunch of blossoms often furnishes in-
stances of regular quincuncial imbrication, of the modification here
referred to, and of a similar disposition of the fifth petal, throwing
one of its edges outwards also. If the first petal were also to par-
take of this slight obliquity, the imbricative would be completely
converted into what is variously named '

498. The contorted, hoisted, or convohttive aestivation (Fig. 430.
441, the corolla, and 442). In this mode, the leaves of the circle are
all, at least apparently, inserted at the same height, and all occupy
the same relative position: one edge of each, being directed ob-
liquely inwards, is covered by the adjacent leaf on that side, while
the other covers the corresponding margin of the contiguous leaf on
the other side. Thi ; i > owing to a torsion or twisting of each member
on its axis early in its development ; lO that the leaves of the floral
verticil, instead of forming arcs of a circle, or sides of a polygon

having for its centre that of the blossom, severally assume an oblique
direction, by which one edge is carried partly inward and the other
outward. This contorted aestivation is rare in the calyx, but corn-

no. 440 Diagram of the plan ami .-estivation of the Mover of the Linden.

FTG 441 Diagram of the imbricated cal} x of Wallflower (two outer and two inner sepals),
and within the strongly contorted or convolute coiolla. 442 Corolla of the latter more open
443. Cross-section of the plaited tube of the corolla of Campanula. 411. Similar section of the
plaited uud supervolute coiolla of Convolvulus.

^ESTIVATION OR PRiKFLORATIOK. 273

mon enough in the corolla. "When this obliquity of position is strong,
the petals themselves are usually oblique, or unequal-sided, from the-
lesser growth of the overlapped side. This is well seen in the pet-
als of most Malvaeeous plants, and in those of the St. Johnswort. In
the Pink, however, and in many other instances, the petals are
symmetrical, although strongly convolute in aestivation. When the
petals are broad, this convolute arrangement is frequently conspicu-
ous in the fully expanded flower, as well as in the bud. The con-
volution in the bud is often so great, that the petals appear as if
strongly twisted or rolled up together, each being almost completely
overlapped by the preceding, so that they become convolute nearly
in the sense in which the term is used in vernation ; as in the Wall-
flower (Fig. 441, 442). Aliiiough there is some diversity of usage,
the terms convolute and contorted in {estivation are now for the most
part employed interchangeably, or nearly so.

499. The valvular or valvate aestivation is that in which the parts
of a floral circle are placed in contact, edge to edge, throughout their
■whole length, without any overlapping, as in the calyx of the Mal-
low and Linden, Fig. 440. Here the members of the circle stand in
an exact circle, no one being in the least degree lower or exterior.
The edges of the sepals or petals jn this case are generally abrupt,
or as thick as the rest of the organ ; by which mark the valvate aes-
tivation may commonly be recognized in the expanded flower.

500. By inflexion of the edges, the valvate aestivation passes by
gradations into the induplicate (Fig.
445), and this, when the margins are in-
rolled, into the involute (Fig. 446), as is

exemplified by the calyx of different spe- ^ *J) ^jjp Q}'
cies of Clematis. On the other hand, the
valvate calyx of many Malvaeeous plants

has the margins projecting outwards into salient ridges, or is redupli-
cate, in aestivation.

501. In the Mignonette, and some other flowers, the aestivation is
open ; that is, the calyx and corolla are not closed at all over the
other parts of the flower in the bud.

502. The form of the tube of the calyx or corolla in the bud
sometimes has to be considered. Sometimes it is plicate, or plaited
lengthwise ; and the plaits may be turned either inwards, as in the

FIG 445 Diagram of the valvate-iuduplicute aest'iTatlon of the calyx of Clematis Virgiui-
ana. 443. Same cf CIcir.atU ViticclU, f.\o issrgtes involute.

274

T1IK FLOWER.

corolla of Gentians, or outward., a; in that of Campanula (Fig. 443).
When these plaits are laid over one another in a convolute manner,
as in the unopened corolla of the Morning-Glory
(Fig. 444) and Stramonium (Fig. 447, 448), the
aestivation is said to be supercolute.

503. The direction of the spire or the overlap-
ping of parts may be either from left to right, or
from right to left ; and this direction is generally
uniform. In indicating the direction, it is most
natural to suppose the observer to stand before
the flower-bud. DeCandolleJ indeed, supposes the
observer to occupy the centre of the flower, which
would reverse the direction ; but the former is the
prevalent view. The direction is frequently re-
versed in passing from the calyx to the corolla,
sometimes with reuiprkable uniformity ; while
again the two occur almost indifferently in many
cases. The h'nd of aestivation, although often the same both in the
calyx and corolla, — as in Parnassia (Fig. 381) and Elodea (Fig.
375), where both are quincuncially imbricated, — is as frequently
different ; and the difference is often characteristic of families or
genera. Thus, the calyx is valvate and the corolla convolute in
all Malvaceae ; the calyx imbricated and the corolla convolute in
Hypericum, in the proper Pink tribe, &c. Solitary exceptions now
and then occur in a family. Thus, the corolla in Ro-aceae is imbri-
cated, so far as known, except in Gillenia, where it is convolute. In
general it may be said, that the aestivation of the corolla is less con-
stant than that of the calyx.

504. The Calj'X. In treating of the general structure and diver-
sities of the flower, we have already noticed the principal modifi-
cations of the calyx and corolla, as well as many of the terms em-
ployed to designate them ; which need not be here repeated.

505. The number of sepals that enter into the composition of a
calyx is indicated by adjectives formed from the corresponding
Greek numerals prefixed to the name ; as, disepalous, for a calyx of
two sepals ; trisepalous, of three sepals ; tetrasepalous, of four ; pen-
tasepalous, of five ; hexasepalous, of six sepals ; and so on. Very
commonly, however, the Greek word for leaves, phylla, is used in

FIG 447. Summit of the uncxpanded corolla of L'atura mcteloiJes. 443 Transverse sec-
tion of the tame.

THE CALYX AND COKOLLA. 275

such composition ; and the calyx is said to be diphylhus, triphyllous,
tetraphyllous, pentapkgllous, hexaphyllous, &c, according as it is com-
posed of two, three, four, five, or six leaves or sepals respectively.
These terms imply that the leaves of the calyx are distinct, or nearly
so. When they are united into a cup or tube, the calyx was by the
earlier botanists incorrectly said to be monophyllous (literally one-
leaved) ; — a term which we continue to use, guarding, however,
against the erroneous idea which its etymology involves, and bearing
in mind that the older technical language in botany is founded upon
external appearance, and not the real structure, as we now under-
stand it. The correct term, calyx gcanophyllous, is now coming into
use : this literally expresses the true state of the case, and is equiva-
lent to the phrase sepals united ; the degree of coalescence being in-
dicated by adding " at the base," " to the middle," or " to the sum-
mit," as the case may be. Still, in botanical descriptions, it is usual
and ordinarily more convenient to regard the calyx as a whole, and
to express the degree of union or separation by the same terms as
those which designate the degree of division of the blade of a leaf
(281-287) : as, for example, Calyx five-toothed, when the sepals of
a pentaphyllous calyx are united almost to the top ; five-cleft, when
united to about the middle ; five-parted, when they are separate
almost to the base ; ixnd five-lobed, for any degree of division less
than five-parted, without reference to its particular extent.

506. The united, portion of a gamophyllous calyx is called its
tube; the distinct portions of the sepals are termed the teeth, seg-
ments, or lobes, according to their length as compared with the tube ;
and the orifice or summit of the tube is named the throat. The
calyx is said to be entire, when the leaves of the calyx arc so com-
pletely confluent <hat the margin is continuous and even. The terms
regular and irregular (44G, 471) are applied to the calyx or corolla
separately, as well as to the. whole flower. The counterpart term to
calyx monophyllous or lnonosepnlous, is polyphyllous or polyscpaloiis
(viz. of many leaves or sepals). This is equivalent to the phrase
sepals distinct ; and does not mean, as the etymology might lead
one to suppose, that they ai*c unusually numerous.

507. The Corolla has corresponding terms applied to its modifica-
tions. When its petals are distinct or unconnected, it is said to be
polypetaloits ; when united, at least at the base, monopetalous, or
more properly gamopetalous, as already explained. Various de-
grees of such union are shown in Fig. 4J0 ~ 4 GO. The united por-

27G

THE FLOWER.

tion.s in the latter case form the tube of the corolla; the distinct parts
are the lobes, segments, &c. ; and the orifice is called the throat,
just as in the calyx. The number of parts that compose the corolla
is designated in the manner already mentioned for the calyx ; viz.
a corolla of two petals is dipetalous ; of three, tripetalous ; of four,
tctrapetalous ; of five, ])entapetalous ; of six, /texapetalous ; of seven,
Iteptapetalous ; of eight, octopetalous ; of nine, enncapctulous ; often,
decapetalous. ,

508. Frequently the petals (and rarely the sepals) taper into a
stalk or narrow base, analogous to the petiole of a leaf, which is
called the data {unguis) ; and hence the petal is said to be unguicu-
late ; as in Cruciferous flowers (Fig. 405), the Pink family (Fig.
432), and Gynandropsis (Fig. 433), &c; the expanded portion, like
that of the leaf, being distinguished by the name of the lamina, limb,
or blade.

509. Some kinds of polypetalous flowers receive particular names,
from the form or arrangement of their floral envelopes, especially of
the corolla. They may be divided into the regular and the irregular,
— terms which have already been defined (446, 471). Among the
regular forms we may mention the rosaceous flower, like that of the
Roe, Apple, &c, where the five spreading petals have no claws, or
very short ones ; the liliaceous, of which the Lily is the type, where
the claws or base of the petals or sepals are erect, and gradually
spread towards their summits ; the caryophyllaceous, as in the Pink
and its allies (Fig. 449), where the five petals have long and narrow

FIG 449. Corolla of Soapwort, of five separate, long-clawed or unglticttlate petals.

FIG 450. Flower of Cilia or Ipomops is coror.opifolia , the parts answering to the claws of
the petals of the last figure here all united into a tube.

FIG 451 Flower of the Cypress- Vine ; the petals a little farther united into a five-lobed
spreading border

FIG 452 Flower of the small Scarlet Morning Glory, the five petals it is composed of per-
fectly united into a trumpet-shaped tube, a^d a nearly entire spreading border.

THK COROLLA.

277

claws, which are enclosed in the tube of the calyx ; and the cruciate,
or cruciform, which gives its name to the Mustard family, where
the four unguiculate petals, diverging equally from one another,
are necessarily disposed in the form of a cross, as in the Mustard
(Fig. 40o). Among

the irregular polypeta- n7 ~--i!""\ s~/<^-

lous flowers, which are ^E^|f''~

extremely varied in

different families, the

papilionaceous or but- . i53 i5i A5i

terflyshaped corolla of the Pulse family is the most familiar, and

has already been illustrated (471, Fig. 392).

510. Several forms of the gamopetalous corolla, or gamophyl-
lous calyx, have been distinguished by particular names. These
are likewise divided into the regular, where their parts are equal in
size, or equally united ; and the irregular, where their size or de-
gree of union is unequal (471). Among the former are the cam-
panulate or bell-shaped, as the corolla of the Harebell (Fig. 45G),
which enlarges gradually and regularly from the base to the summit ;

the infundibidiform, or funnel-shaped, where the tube enlarges very
gradually below, but expands widely at the summit, as in the corolla
of Morning-Glory (Fig. 1035 and 452) ; tubular, where the form is
somewhat cylindrical throughout, as in Trumpet Honeysuckle ; hypo-
crateriform (more correctly hypocraterimorphous), or salver-shaped,

Rotate or wheel-shaped and five-parted corolla of the Bittersweet (Solanum

FIG 453.
Dulcamara)
FIG. 454
FIG 455
FIG 456

Wheel-shaped and five-cleft corolla of the common Potato.

The almost entire and open bell-shaped corolla of a Ground Cherry (Physalis).

Canipanulate corolla of the Harebell, Campanula rotundifolia 457 Salver-
shaped corolla of Phlox. 45S. Labiate (ringent) corolla of Lamium ; aside view 459. Per-
sonate coivlla of Antirrhinum 4C0. Personate corolla of Liuaria, spurred at tho base.

' 24

278 THiC i LOWER.

where the limb spreads at right angles with the eummit of the more
or less elongated tube, as in the corolla of Cypress- Vine (Irig. 451)
and Phlox (Fig. 457) ; and rotate, or whetl-shaped, when a hypo-
crateriform corolla has a very short tuhe, as in the Forget-me-not, Bit-
tersweet (Fig. 453), and Potato (Fig. 454).

511. The principal irregular gamopetalous or gamophyllous forms
that have received a separate appellation are the Ugulate or strap-
shaped, which has already been explained (473), and the labiate or
bilabiate. The latter, as already stated, is produced by the unequal
union of the sepals or petals (473), so as to form an upper and a lower
part, or two lips, as they are called, from an obvious resemblance to
the open mouth of an animal (Fig. 458-460). This variety is al-
most universally exhibited by the corolla of the Sage or Mint family
(which is therefore called Labiatai), as well as of several related
families ; and the calyx is frequently bilabiate also, as in the Sage.
And since, in the corolla of these families, two of the five petals
enter into the composition of the upper lip, and three into that of the
lower, this is necessarily inverted in the bilabiate calyx, three of the
sepals combining to form the upper lip, and two to form the lower.

512. When the upper lip is arched, as in the corolla of Lamium
(Fig. 458), it is sometimes called the galea, or helmet. When the
two lips are thus gaping and the throat open, the corolla is said to
be ringent. When the mouth is closed, or partly so, by an elevated
portion or protuberance of the lower lip, called the palate, as in the
Snapdragon and Toadflax (Fig. 459, 4C0), the corolla is said to be
personate, or masked.

513. In the Snapdragon, the base of the corolla is somewhat pro-
tuberant, or saccate, on the anterior side ; in the Toadflax, the pro-
tuberance is extended into a hollow spur. A projection of this kind
is not uncommon, in various families of plants. One petal of the
Violet is thus spurred or calcarate (Fig. 397) ; so is one of the outer
petals in the Fumitory, and each of them in Dieentra (Fig. 370). So,
also, one of the sepals is spurred or strongly sac-shaped in the Jewel-
weed (Impatiens), and the Larkspur (Fig. 398) ; and all five petals
take this shape in the Columbine. A monster of the Toadflax is
occasionally found, in which the four remaining petals of the five
which enter into its composition, affect the same irregularity, and so
bring back the flower to a singular abnormal state of regularity.
This was called by Linnams Peloria ; a name which is now used to
designate the same sort of monstrosity in different flowers.

THE STAMENS. 279

. 514. The petals are sometimes furnished with appendages on
(heir inner surface, such as the crown at the summit of the claw in
Silene (Fig. 378, 449), and the scales similarly situated on the
gamopetalous corolla of the Comfrey, &c. These appendages some-
times represent a circle of sterile and metamorphosed stamens ; but
more commonly they seem really to belong to the petal.

515. As to duration, sometimes the floral envelopes are caducous,
i. e. falling off when the blossom opens, as the calyx in the Poppy fam-
ily and the corolla of the Grape-Vine (Fig. 384). More commonly
they are deciduous, or fall after expansion, but before the fruit forms.
When they remain until the fruit is formed or matured, they are
persistent, which is often the case with the calyx, especially when
it has a green color and foliaceous texture. When they persist in a
dry or withering state, as the corolla of Heaths, Campanula, &c,
they are said to be marcescent.

516. Besides serving as organs of protection, the sepals, when
green, assimilate sap, and act upon the air like ordinary foliage (344,
345). The petals, like other uncolored (that is greenless) parts, do
not evolve oxygen, but abstract it from the air, and give off carbonic
acid; in other words, they decompose assimilated matter, — a pro-
cess which appears to be needful in flowering, and to subserve some
important end at the time (3C8-373). The tissue of a petal is
much the same as that of a leaf, except that it is much more delicate
and the fibro-vascular system is generally reduced to slender bundles
of a few spiral vessels, &c, which form its veins.

Sect. VI. Tin-: Stamens.

517. The Stamens have already been considered in a general way
(418). Before describing their structure more particularly, the
principal terms which relate to their number, connection, and posi-
tion may be mentioned. Most of these terms were devised by Lin-
naeus as names of the classes of his Artificial System of classification
(Part II. Chap. IV.), founded mainly upon characters furnished by
the stamens. Their number in a flower is accordingly expressed
by the names of the eleven or twelve earlier Linmean classes (990),
put into adjective form. Thus, a flower with one stamen is said to
be monandrous ; with two, diandrous ; with three, triandrotis ; with
four, tetrandrous ; with five, pentandrous ; with six, hexandrous ;

with seven, heptandrous ; willi eight, octandrous ; with nine, cnnean-
drous ; with ten, decandrous ; with twelve, dodecandrous. When
more than twelve, and inserted on the calyx, they are isocandrous, or
when inserted on the receptacle, polyandrous.

518. As to their union with each other, this may take place in
various ways. Sometimes the filaments are combined, while the
anthers are distinct. "When thus united by their filaments into one
set, they are said to be monadelphous ; as in the Lupine, &c. (Fig.

4G2) and Mallow.
"When united by their
filaments into two
sets, they are diadcl-
phous, as in most
plants of the Pulse
family, Avherc nine
stamens form one set
and the tenth is soli-

401 462 463 4S4 ,,,.,„ i

tary (I'ig. 401) ; and
in Dicentra (Fig. 3 GO - 371), where the six stamens are equally com-
bined in two sets. When united or ar-
ranged in three sets or parcels, they are
said to be triadelphous, as in the com-
mon St. Johnswort ; or if in several,
polyadelphous ; as in Linden. When
stamens are united by their anthers into
a tube or ring, they are said to be syn-
genesious (Fig. 4G3, 464). This occurs
in the whole vast order of Composite.
Here the five filaments are distinct ;
whereas in Lobelia, and also in the
Melon and Gourd (Fig. 465, 466), both
the filaments and the anthers are united
monadelphous as well as syngenesious.

519. As to insertion, stamens are hypogynous (4GG) when b6rne
on the receptacle, that is, when not adnate to any other organ ;

that is, the stamens are

FIG. 4G1 Diadelphous ^tamens (3 and 1) of a Pea. 4G2 Monadelphous stamens of a
Lupine.

FIG. 4G3 Five syngeiesious stamens of a Composita. 4G4. The same, laid open.

FIG 4G5. Column of stair.cns at o::ce triadelphous and syesenesious. of the Gourd : the
floral envelopes cut away. 4G3. A crosj-scctiou of tile united anthers, nearly the natural size.
4G7. A sinuous anther of the Melon.

TIIK STAMENS.

281

"^

perigynous (4G7) when borne on or adnate to any part of the calyx ;
epipetalous, when borne on the corolla, as in the greater number of
monopetalous flowers ; and epigynous (469),
■when borne on the ovary. In some cases the
ndnation proceeds further, and the stamens are
inserted on, i. e. are consolidated with, the
style, as in the Orchis family ; then they are
said to be gynandrous (Fig. 4G8).

520. There are two cases in which inequal-
ity in the length of the filaments is expressed by
a technical term. Namely, the stamens are
said to be didynamous when, being only four
in number, they are in pairs, and one pair is

longer than the other ; as in Gerardia (Fig. 407), and in most flowers
with a bilabiate corolla. And they are tetradynamous when, being
six in number, two are shorter than the remaining four, as in Mus-
tard and all that family of plants with Cruciferous flowers (Fig. 40G).

521. A stamen consists of its filament and its anther (418).
The filament, being a mere stalk or support of the anther, is not an
essential part ; it is to the anther what the petiole is to the blade of
a leaf. Sometimes, therefore, it is wanting, when the anther is
sessile. The anther is essential to a perfect stamen. But sometimes
a stamen, or what stands in the place of one, is destitute of an aniher,
i. e. is sterile, as in Fig. 408; and al o the upper one in Fig. 408,
St., which is a sterile filament enlarged into a petal-like body. The
true nature of the organ is known by its position.

522. TllC Filament, although usually slender and stalk-like, assumes
a great variety of forma : it is sometimes dilated so as to resemble a
petal, except by its bearing an anther; as in the transition states be-
tween the true petals and stamens of the Water-Lily (Fig. 844). The
filament is anatomically composed of a central bundle of spiral ves-
sels or ducts, which represent the fibre-vascular system of the leaf,
in the same state as in the petiole, enveloped by parenchyma; the
outer stratum of which forms a delicate epidermis.

523. The Anther, which is the essential part of the stamen, is usu-
ally borne on the apex of the filament ; and commonly consists of
two lobes, or cells (thecce), placed side by side, and connected by a
prolongation of the filament, called the connectivum, or connective.

I'TG. 4C8. Stamens ami stjle of a Oypripedium, united into one body or column:
ant.icra : si. a sterile stamen : *hg t!io stigma.

21*

282

THIi FLOWEK.

524. The attachment of the anther to the filament presents three
principal modes. 1st. When the base of the connective exactly
corresponds with the apex of the filament and with the axis of the
anther, the latter is termed innate, and rests firmly upon the summit

of the filament, as in Fig. 4G9. 2d.
When the lobes of the anther adhere
for their whole length to a prolonga-
tion of the filament, or to a broad
connective (whichever it be called),
so as to appear lateral, it is said to
be adnata ; as in Magnolia, Lirio-
dendron (Fig. 470), &c. Here the
anther must be either cxtrorse or in-
trorse. It is inirorse, or turned in-
430 47U 4" wards, when it occupies the inner

side of the connective, and faces the pistils, as in Magnolia ; but
when the anther looks away from the pistils and towards the petals
or sepals, it is said to be cxtrorse, or turned outwards, as in Iris,
Liriodendron, and Asarum (Fig. 472). 3d. When the anther* is
fixed hy a point near its middle to the apex of the filament, on which
it lightly swings, it is said to be versatile ; as in all Grasses, in the
Lily, and in the Evening Primrose (Fig. 471), &c. In this case, as
in the preceding, the anther is said to be introrse, or incumbent,
when it is turned towards the pistil, which is the most common
way ; and extrorsc, when it faces outwards.

525. The connective is often inconspicuous or wholly wanting, so
that the lobes of the anther are directly in contact on the

apex of the filament ; but it is commonly evident. It is
often produced into an appendage at the tip of the anther,
as in Magnolia and Liriodendron (Fig. 470), the Papaw
(Fig. Do 6, where it forms a rounded top), and Ararum
(Fig. 472). Appendages or processes from the back of
the connective are seen in the stamens of the .Violet and of
many Ericaeeous plants. 4'2

526. Each of the two cells or lobes of the anther is marked with
a lateral line or furrow, running from top to bottom ; this is the

FIG. 4G9 A stamen of Isopy rum biternatum, -with an innate anther 470. Stamen of Lirio-
dendron, or Tulip-tree, with an adnate extrorse anther. 471. Stamen of (Euothera glauca,,
■with the anther fixed by its middle and versatile.

VIG. 472. A stamen of Asarum Cauaderuc, with an adnate anther.

T1IK AXTHKR.

283

nature, or line of dehiscence, by which the anther opens at maturity
tO'disclmrge the pollen (Fig. 473). This line is for the most part
exactly lateral in innate anthers ; but it looks more or less evidently,
and often directly, inward in introrse, and outward in extrorse
anthers. In certain eases the cells of the anther open only at the
summit, by a pore or hole, as in Py-
rola (Fig. 474) and most Ericaeeous
plants. In the Whortleberry family
each cell or lobe is commonly pro-
longed into a tube, which opens only
at the apex ( Fig. 391). In the Bar-
berry (Fig. 475), and in nearly all
plants of the Barberry family, the
whole face of each anther-cell sepa- 473 m 473

rates by a continuous line, forming a kind of door, which is attached
at the top, and turns back, as if on a hinge : in this case the anthers
are said to open by valves. In the Sassafras (Fig. 1114), and many
olher plants of the Laurel family, each lobe of the anther opens by
two such valves, like trap-doors.

527. Sometimes the anthers are one-celled by the suppression of
one lobe, being dimidiate, or reduced as it were to half-stamens, as

in Gomphrena or Globe-Amaranth (Fig. 478).
But most one-celled anthers are the result of
the confluence of the two cells into one. A
comparison of the two-celled anther of Pent-
stemon pubescens, where the two cells diverge
below and are somewhat united at the top
(Fig. 47G) with the kidney-shaped one-celled
anther of a Mallow, opening by a continuous
line all round the margin (Fig. 477), shows
how this result is brought about.

528. As to anatomical structure, each lobe of the full-grown
anther consists of an epidermal membrane, lined with a delicate
fibrous tissue, and surrounding a cavity filled with pollen. This

FTG 473. A stamen, with its anther, 6. opening in the normal manner down the whole
length of the outer side of each cell : a, the filament

FIG. 474 Stamen of a P) rolu. ; each cell of the anther opening by a terminal orifice.

FIG. 475. Stamen of a Barberry ; the cells of the anther opening by an uplifted valve.

FIG. 476 A stamen of rentstemon pubescens ; anther-cells slightly confluent

FIG. 477. Stamen of Mallow ; the two cells confluent into one, opening round tho margin.

FIG 478. Antlier of Globe Amaranth, of only oce cell ; the other cell obliterated.

284

THt: FLOWER.

fibrous lining (a little of which is shown in Fig. 45, from the anther
of Cobiea) is composed of simple or branching threads or bands,
which formed the thickening deposit on the walls of large paren-
chymatous cells ; all the membrane between the bands becoming ob-
literated as the anther approaches maturity, the latter alone remain,
us a set of delicate fibres. This fibrous layer gradually diminishes
in thickness as it approaches the line of dehiscence of the cell,
and there it is completely interrupted. These very elastic and hygro-
metric threads lengthen or contract in different ways, according
as the anther is dry or moist, and are thought to favor the egress
of the pollen. The outer stratum of the wall of the anther in dry-
ing contracts more than the inner, and so opens the cell, in many
cases turning the walls inside out after dehiscence, as in Lilies
and Grasses.

529. Of all the floral organs, the anther shows least likeness to
a leaf. Nevertheless, the early development is nearly the same.
Like the leaf, the apex is earliest formed, appearing first as a solid
protuberance, and the anther is completed before the filament, which
answers to the leafstalk, makes its appearance. At first, the anther
is of a greenish hue, although at maturity the cells assume a differ-
ent color, more commonly yellow. A transverse section of the form-
ing anther shows four places in which the transformation of the paren-
chyma into pollen commences, which answer to the centre of the
four divisions of the parenchyma of a leaf, viz. the two sides of the
blade, each distinguished into its upper and its lower stratum. So
that the anther is primarily and typically four-celled ;
each lobe being divided by a portion of untransformed
tissue, stretching from the connective to the opposite
side, which corresponds to the margin of the leaf and
the line of dehiscence. This appearance is presented
by a large number of full-grown anthers : but the par-
tition usually disappeai-s before the anther opens, when
each lobe becomes single celled. The normal anther
is consequently considered as two-celled. In Meni-
spermum and Cocculus, however, the anther is strongly
four-lobed externally, and each lobe forms a distinct
473 cell at maturity.

530. Viewed morphologically, therefore, the filament answers to

FIO 479. IMan of a stamen as answering to a leaf ; t'.ie upper part of the anther cut away,
and the summit of a leaf represented above it.

Tllli POLLEN.

285

the petiole of a loaf; the anther, to the blade. The connective
represents the midrib ; the lobes or cells of the anther represent the
two symmetrical halves of the blade ; and the line of dehiscence is
normally along the margins of the transformed leaf. What in the
leaf would be cells of parenchyma develop as

531. Pollcil. This usually powdery substance consists of grains,
of definite size and shape, uniform in the same plant, but often very
different in different species or families. The grains are commonly
single cells, globular or oval in shape, and of a yellow color. But
in Spiderwort they are oblong; in the Cichory and Thistle tribes
many-sided (Fig. 485) ; in the Musk-plant spirally grooved (Fig.
480) ; in the Mallow family (Fig. 483) and the Squash and Pump-

kin, beset with bristly projections, &c. The pollen of Pine (Fig.
486), as well as that of the Onagracerc (Fig. 487, 489), is not so
simple, but appears to consist of three or four blended cells ; that of
all true Ericaceae evidently consists of four grains or cells united

434 485 483 487 488

(Fig. 488). The most extraordinary shape is that of Zostera, or
the Eel-grass of salt-water, in which the grains
(destitute of the outer coat) consist of long and
slender threads, which, as they lie side by side
in the anther, resemble a skein of silk.

532. Pollen-grains are usually formed in fours,
by the division of the living contents of mother
cells first into two, and these again into two parts, which, acquiring
a coat of cellulose, become specialized cells (36). As the pollen
completes its growth, the walls of the mother cells are usually oblit-
erated. But sometimes the enclosing cells persist, and collect the

FIG. 480-489 Forms of pollen : 480, from Miuiulus mosehatus : 481. Sicyos: 482, Eehl-
nocystis: 483, Hibiscus: 484, Lily: 485, Cichory: 486, Pine: 487, Cireaea : 488, Kaluiia :
489, Evening Primrose.

286 TUB FLOWER.

pollen-grains into coherent masses of various consistence, as is re-
markably the ease in the Orchis and Milkweed families (Fig. 543,
&c). Such pollen-masses are sometimes termed pollinia.

533. The thread?, resembling cobweb, that are loosely mixed with
the pollen of the Evening Primrose, are the vestiges of obliterated
mother cells.

534. Pollen-grains have two coats. The outer coat, called the
extine, is comparatively thick, and often granular or fleshy. This is
later formed than the inner, and by a kind of secretion from it : to it
all the markings belong. The inner coat, or intine, which is the
proper cell-membrane, is a very thin and delicate, transparent and
colorless membrane, of considerable strength for its thickness. The
pollen of Zostera and of some other aquatic plants is destitute of the
outer coat (531).

535. The cavity enclosed by the coats is filled with a viscid liquid,
rich in protoplasm, which often appears slightly turbid under the
higher powers of ordinary microscopes, and, when submitted to a
magnifying power of about three hundred diameters, is found to
contain a multitude of minute particles (fovillce), the larger of
which are from the four-thousandth to the five-thousandth of an inch
in length, and the smaller only one fourth or one sixth of this size.
The smaller exhibit the constant molecular motion of all such mi-
nute particles when suspended in a liquid and viewed under suffi-
cient magnifying power. When wetted, the grains of pollen prompt-
ly absorb water by endosmosis (37), and are distended, changing
their shape somewhat, and obliterating the longitudinal folds, one or
more in number, which many grains exhibit in the dry state. Soon
the more extensible and elastic inner coat inclines to force its way
through the weaker parts of the outer, especially at one or more
thin points or pores ; sometimes forming a projection of considerable
length, when the absorption is slow and the exterior coating tough.
If the absorption continues, the distention soon overcomes the resist-
ance of the elastic inner coat, which bursts, and the contents are dis-
charged.

536. When fresh, living pollen falls upon the stigma, however,
which is barely moist, it does not burst, but the inner membrane is
slowly projected, often through particular points, clefts, or openings
of the outer coat, in the form of an attenuated transparent tube (Fig.
537 — 547), filled with its fluid contents, and which penetrates the
naked and loo^e cellular tissue of the stigma, and buries itself in

Tin-; pistils. 287

the stylo. This is not a mechanical protrusion, but a true growth,
the materials for which are supplied by nourishment imbibed from
the stigma and style. Its further course and the office it subserves
will be considered after the structure of the pistil is made known.
(Sect. IX.)

Sect. VII. The Pistils.

537. The Pistils (419) occupy the centre of the flower, and ter-
minate the axis of growth. Linnaeus established the orders of his
Artificial System mainly upon the pistils, and this introduced a se-
ries of terms expressive of their number in a flower, analogous to
those used for the number of stamens (517). Thus a flower with a
single pistil is said to be monogynous ; with two, digynous ; with three,
trigynous ; with four, tetragynous ; with five, pentagynous ; and so
on : when more numerous or indefinite, the flower is polygynous.

538. It is comparatively seldom that the pistils are exactly equal
to the petals or sepals in number ; they are sometimes more numer-
ous, and arranged in several rows upon the enlarged or prolonged
receptacle, as in the Magnolia, the Strawberry, &c., and perhaps
more frequently they are reduced to less than the symmetrical num-
ber, or to a single one. Yet often what appears to be a single pistil
is not so in reality, but a compound organ, formed by the union of
two, three, or a greater number of simple pistils ; these organs being
subject to coalescence in the same way as the stamens (518) and the
petals (507, 4G2).

539. A simple and complete pistil, as already described (420), is
composed of three parts : the Ovary, or seed-bearing portion ; the
Style, or tapering portion, into which the apex of the ovary is pro-
longed ; and the Stigma, usually situated at the summit of the style,
consisting of a part, or sometimes a mere point, of the latter, divested
of epidermis, with its moist cellular tissue exposed to the air. The
ovary, which contains the ovules, or bodies which are to become
seeds, is of course a necessary part of the pistil ; the stigma, which
receives from the anthers the pollen (531) by which the ovules are
fertilized, is no less necessary ; but the intervening style is no more
essential to the pistil than the filament is to the stamen, and is there-
fore not uncommonly wanting. In the latter case, the stigma is
sessile upon, the apex of the ovary. In Tasmaimia it actually occu-
pies the side of the ovary for nearly its whole length, and is sepa-

288 THE FLOWKR.

rated from the line to which the ovules are attached only hy the
thickness of the walls : it is nearly the same in our Sehizandra
(Fig. 490), another plant of the Magnolia family. The style some-
times proceeds from the side, or even from near the apparent hase
of the ovary; as in the Strawberry (Fig. 428).

540. When the pistil is single, or when several coalesce into one, it
will necessarily terminate the axis, and appear to be a direct con-
tinuation of it. When there are two pistils in the flower, they al-
ways stand opposite each other (so that if they coalesce it is by
their inner faces) ; and are either lateral as respects the flower, that
is, one on the right side and the other on the left, in a plane at right
angles to the bract and axis (444), as in the Mustard family, the
Gentian family, and a few others ; or, more commonly, anterior and
posterior, one before the axis and the other before the bract of the
axillary flower. When they accord in number with the sepals or
petals, they are either opposed to or alternate with them ; and the
two positions in this respect are sometimes found in nearly related
genera, so as to baffle our attempts at explaining the cause of the
difference. In Pavonia, for example, the five pistils are opposite
the petals ; in Malvaviscus and Hibiscus, alternate with them. In
Sida (when five) they stand opposite the petals ; in Abutilon, opposite
the sepals.

541. Pistils occur under such a diversity of forms, and exhibit
such various complications, that the plan of their structure and the
distinction between simple and compound pistils require to be well
understood. Commencing, therefore, with the mot natural forms,
and proceeding gradually to the more complex or disguised, we first
consider

542. The Simple Pistil, and the way in which it answers to a loaf.
A simple pistil answers to a single leaf. A compound pistil answers
to two or more leaves combined, just as a monopetalous corolla
answers to two or more petals, or leaves of the flower, united into
one body. As to its morphology, the botanist regards a simple
pistil as consisting of the blade of a leaf, curved inwards until its
margins meet and unite, forming in this way a closed case, or pod,
which is the ovary. So that the upper face of the altered leaf
answers to the inner surface of the ovary, and the lower, to its
outer surface. And the ovules are borne on what answers to the
united edges of the leaf. The tapering summit, rolled together
and prolonged, forms the style, when there is any ; and the edges

THE SIMPLE TISTIL.

289

of the altered leaf turned outwards, either at the tip or along the
inner side of the style, form the stigma. This will be clearly un-
derstood on comparing Fig. 342 and Fig. 491, which are pistils
transversely divided, with Fig. 490, a leaf curved inwards until its
margins nearly meet, and with Fig.
492, a simple pistil of Caltha or
Marsh-Marigold which has matured,
split open along the inner side to
discharge the seeds it bore, and
spread out into the shape of a leaf.

543. The line formed by the union
of the margins of the leaf is called
the Inner or Ventral Suture, and
always^Jooks towards the axis of the
flower. This is a true suture, or

seam, as the word denotes. The opposite line, answering to the mid-
rib, is sometimes apparent as a thickened line, and is termed the
Outer or Dorsal Suture. The ovules or young seeds are borne (in
all ordinary cases at least) on the inner suture, or some part of it;
that is, on what answers to the united margins of the infolded and
transformed leaf. The part in the cell of the ovary to which the
ovules are attached, and which is commonly more or less enlarged
or projecting when the ovules are numerous, is named

544. TllC Placenta. As this corresponds with the ventral suture,
and is in fact a part of it, or a cellular growth from it, it always

.belongs next the axis of the flower;
as is evidently the case when two,
three, or more pistils are present.
Each placenta necessarily consists of
two parts, one belonging to each margin
of the transformed leaf. It therefore is
frequently two-lobed, or of two diverg-
ing lamella? (Fig. 342). This shows
why the ovules are apt to occupy two longitudinal rows, as in

FIG 490 A leaf infolded, to illustrate the theory of the formation of the pistil

FIG. 491. Pistil of Isopyrum biternatum, cut across ; the inner or ovule-bearing side
turned towards the observer.

FIG 492. Ripe pistil of Caltha palustris, after opening and discharging the seeds.

FIG. 493 Vertical section of a pistil of Schizandra
Hydrastis. 495. Pistil of Actaea rubra, cut across,
ventr.il suture turned towards the observer).

25

a side view 494 Pistil of
i as to show the interior of the ovary (the

290 Tin: flower.

the figure last cited, and in Fig. 491, 495, &c., one row belonging to
each margin of the leaf. A simple pistil, accoidingly, can have
only one placenta; but that is structurally double.

545. So a single pistil can have only one style and one stigma.
But as the stigma answers to the margins of the apex of the leaf,
this must also be double in its nature. And this is evidently the
case in the Peony and Isopyrum (Fig. 491), in the Tulip, as well
as in Fig. 493-495, and in almost all cases in which the stigma
extends down the inner face of the style, as it frequently does.
Such unilateral stigmas we accordingly take to be the typical form ;
and say that, while the united margins of the transformed leaf which
compose the ventral suture are turned inwards into the cell of the
ovary to bear the ovules, in the simple style they are exposed external-
ly to form the stigma. Where the stigma is terminal, or occupies
only the apex of the style, we suppose that these margins are in-
folded in the style also, and form in its interior the loose conducting
tissue through which a communication is established between the
stigma and the interior of the ovary.

54G. The ovary of a simple pistil obviously can have but one
cavity or cell ; except from some condition out of the natural order
of things. But the converse does not hold true : all pistils of a sin-
gle cell are not simple. Many compound pistils are one-celled, as
will presently be explained.

547. A leaf or member of the gynajcium then, when separate,
forms a simple pistil ; when combined with others, it makes part of a
compound pistil. It is convenient to have a name which shall desig-
nate a single pistil-leaf, whether occurring as a distinct simple pistil,
or as an element of a compound pistil. For this purpose the name
of Cakpkl has been devised. A carpel is either a simple pistil,
or is one of a circle of leaves which compose a compound pistil.
When the pistils are distinct from each other, they are said to be
apocarpous ; when united into one body, syncarpous. This union
produces a

548. Compound Pistil. All degrees of union of the carpels may
be observed, from the coalescence of the lower part of their ovaries,
their summits remaining separate (as in Fig. 49G), or from the com-
plete union of the ovaries into one body, the styles remaining sepa-
rate (as in Fig. 497), to the complete coalescence of the styles also
(Fig. 498), and even of the stigmas (Fig. 499), into one body. It is
evidently the same as if two or more pistils (in Fig. 497 - 499, three

THE COMPOUND PISTIL.

291

pistils) were pressed together as they grew and consolidated more or
less completely into one. And in this, the most normal case, we have
as the result compound pistils

549. With two or more Cells and Axilc Placcutcc. For it is evident

that, if the contiguous parts of a whorl of three or more closed car-
pels cohere, the resulting compound ovary will have as many cavi-
ties, or cells, as there are carpels in its composition, and the placenta;
(one in the inner angle of each carpel) will all he hrought together
in the axis of the compound pistil. And the partitions, or Dissep-
iments, which divide the compound ovary into cells, manifestly
consist of the united contiguous portions of the
walls of the carpels. These necessarily are
composed of two layers, one helonging to each
carpel ; and in ripe pods they often split into
the two layers. True dissepiments must always
be equal in number to the carpels of which the
compound pistil is composed.

550. In certain cases, indeed, there are addi- 50°

tional partitions, or false dissepiments. These are commonly projec-

FIG. 496. Pistil of a Saxifrnge composed of two carpels or simple pistils united below, but
distinct above ; cut across both above and below.

FIG. 497 Pistil of common St Johnswort, of three united ovaries ; their styles distinct.

FIG. 498. The same of another species of St Johnswort (Hypericum prolificum), the styles
also united into one, which, however split apart in the fruit

FIG. 499. Pistil of Tradcscantia or Spideru ort, even the three stigmas united into one.
The ovary in all cut across to show the internal structure.

FIG. COO Cross-scclion of a flower of Flax- each of the five cells of the ovary partly divided
by an imperfect false partitiou from th.o back.

292

THE FLOWER.

tions or growths from the dorsal suture ; whether in a simple pistil (as
that of mo.4 species of Astragalus, Fig. 805), or from the back of
each proper cell of a compound pistil, as in the Service-berry, the
Blueberry, and the common Flax (Fig. 500).

551. We have considered only the case of compound pistils of two
or more cells in the ovary. But compound pistils also not unfre-
quently occur

552. Willi only one Cell. And of these there are two kinds to be
noticed, those with axile, and those with parietal jjlacentce. That is,
in the first, the ovules are borne in the axis or centre of the ovary,
either at the base or on a column which occupies the centre ; in the
second, they are borne on some part of the parietes or walls of the
ovary. The first, viz.

553. With a Free Central Placenta, is found in the Primrose, Purslane
(Fig. 389), and Pink families (Fig. 432, 501, 502).
In the Pink family this evidently results from the ob-
literation of the dissepiments (as many as there are
styles or stigmas) ; and vestiges of these may be de-
tected at an early stage, and sometimes at the base of
the full-grown ovary ; while certain plants of the same
family, of otherwise identical structure, retain the par-
titions even in the ripe pod. In other instances, as in
Diomea, Thrift, &c, this is doublless a modification of
parietal placentation, with ovules produced only at the
bottom. This brings us to the case of compound one-
celled pistils

554. With Pai'ielal PlaceiltJE, that is, with the placenta? borne on
the sides or parie-
tes of the ovary, ^^
as in the Poppy, /
Caper, Cistus or ( -? y'
Rock-Rose (Fig.
507), Violet, Sun-
dew (Fig. 510),

and Currant families, and many others. To comprehend this per-

FIG 501. Vertical section through the compound tricarpellary ovary of a plant of Spergu-
laria rubra, showing the free central placenta 502. Transverse section of the same

FIG 503-505. Diagrams illustrating parietal and free central placentation. 503 Cross-
section of a tricarpellary ovary, with a free central placenta, produced by the obliteration of
the dissepiments. 504. Section of an ovary with.three strictly parietal placentae. 505. Same,
•xcept that there are incomplete partitions.

THE COMPOUND PISTIL.

293

fectly, we have only to imagine two, three, or any number of pistil-
leaves (like Fig. 490), arranged in a circle, to unite with one another
by their contiguous edges, either without any intro-
■flexion or infolding at all (Fig. 504), or at least
without their infolded edges having reached the cen-
tre and united there (Fig. 505, 50G). The combina-
tion is accordingly much like that by Avhich petals
unite to form a monopetalous corolla, only the edges
of the pistil-leaves are always turned in, where they
bear the ovules. Such an ovary may
well be compared with the valvate un-
opened calyx of Clematis, the margins
of the sepals more or less turned in-
warcb (Fig. 445). Every gradation is
found between axile and parietal pla-
ccntalion, especially in the St. Johns-
wort family (Fig. 508, 509) and in the Gourd family.

An ovary with parietal placentae is necessarily one-celled;
it be divided by an anomalous partition, such as is found in
Cruciferous plants, and in the Trum-
pet Creeper.

556. It will be seen that parietal
placentae are necessarily double, like
the placenta of a simple ovary, or of
each carpel of a compound several-
celled ovary ; but with this difference,
that in these the two portions belong to the two margins of the
same carpel ; while in parietal placenta? they are formed from the
coalescent margins of two adjacent carpels.

557. The number of carpels of which a compound ovary consists
is indicated by the number of true dissepiments when these exist ;
or by the number of placenta?, when these are parietal ; or by the
number of styles or stigmas, when these are not wholly united into
one body. Thus a simple pistil has a single cell, a single placenta,

ooo.

except

FIG 506. Plan of n. onc-rellcd ovary with three parietal placentae, cut across below ; the
upper part showing the top of the three leaves it is composed of, approaching, but not united

FIG. 507 Ovary of Ilelianthemuni Canadense, cut across, showing tho ovules on three
parietal placentae.

FIG. 508 Transverse section of the ovary of Hypericum graveolens ; the three large
placentae meeting in the centre, but not cohering. 509 Similar section of a ripe pod of the
lame; the placentas now evidently parietal

25*

294 THE FLOWEK.

and a single style. A pistil of two carpels may be two-celled, Avith
two placenta-!, two styles, or two stigmas, &c*

* There arc, however, some exceptions which qualify these statements : —
1 Each placenta being a double organ (556) it occasionally happens that
the two portions arc separated more or less, as in Oiobanchaccous plants, where
a dicarpcllary ovary appears on this account to have four parietal placenta; ;
either approximate in pairs (as in our Cancer-root, Conopholis), or equidis-
tant (as in Aphyllon)

2. Analogous to this is the case where the two constituent elements of the
stigma (the only essential part of the style) .separate into two half-stigmas, as is
partially seen in Fig. -194, 495. The stigma, no less than the placenta, belongs

to the margins of the infolded leaf (545), these maigins being
ovnliforous in the ovary and stig matijerous in the style ; as Mr.
Brown, the most profound botanist of this or any age, has
clearly shown. These two constituent portions of the style or
stigma occasionally separate, cither entirely or in part, as in
Euphorbiaccous plants, in Grasses, and especially in Droscra
(Fig. 510), where there arc consequently twice as many neatly*
distinct styles as there arc paiietal placenta in the compound
ovary If the two component parts of the style of each carpel
were reunited into one, in the usual manner, their number
would equal the placentas, and their position Mould be alter-
nate with the latter But since, in parietal placental ion, each
half-placenta is confluent (not with its fellow of the same
carpel, but) with the contiguous half-placenta of the adjacent cai pel, it wcic suiely
no greater anomaly for the elements of such hdlfsiiijmas as those of Droscra to
follow the same course. This is precisely what takes place in Farnassia, and in
other cases where the stigmas aic opposite the parietal placenta; ; — cases which
were thought to be very anomalous, merely on account of the adoption of a
false principle (that of the ncccssaiy alternation of the stigmas and placenta;),
but which arc really no more extraordinary than parietal placcntation itself

3. Fmthcrmorc, the production of ovules is not always restricted to what
answers to the margins of the carpcllary leaves. In the Poppy, the whole sur-
face of the long, imperfect partitions is covered with ovules ; in Butomus, they
are borne over the whole internal face of each carpel, and in Water-Lilies over
the whole surface, except the inner angle of each cell, where alone they normally
belong. Reduced to two in the allied Water Shield (Brascnia, Fig. 684), the
ovules grow from the dorsal suture, or the midiib of the carpcllary leaf alone !
And in the allied Cabomba itself we usually find its three ovules, one on the
dorsal and one on the ventral suture, and the third on some variable pail of the
face of the cell in the vicinity of cither suture. In Obolaria, Bartonia (Ccntau-
rclla, Michx ), and in several species of Gentian, a compound one-celled ovary is
ovuiiferous over the whole face of the cell !

All placcntation is very differently explained by those who adopt the hypoth-

FIG. 610 Pistil of Drosera filiformis, with three deeply two-parted styles : the oyarj cut
tcrois, showing three parietal placentae.

THE COMPOUND PISTIL. 20.>

558. TFhen the styles are separate towards the stnrfmit, but
united below, they are usually described as a single organ ; which
is said to be parted, cleft, lobed, &e., according to the extent of cohe-
sion. This language was adopted, as in the case of leaves (281)
and floral envelopes (4G2), long before the real structure was under-

csis of Sehlcidcn, Endlichcr, awl others. Aceouling to this new view, since buds
rcgulaily aiisc from the axils of leaves and fiom the extremity of the stem or
axis, and only in some exceptional and abnormal cases fiom the margins or
sin face of leaves, so ovnlcs, which are viewed as a form of buds, arc considered
to arise from the receptacle, cither from the axis of the flower, like terminal
buds, or fiom the axils of the carpcllaiy leaves, like axillary buds. Thus,
placentae arc supposed to belong to the stem, and not to the carpcllaiy leaves ;
and a onc-ccllcd ovaiy, with one or more ovules aiising fiom the base of the
cell, would nearly represent the typical state of the gynaicium. This thcoiy,
which the intelligent student may easily apply in detail, offeis a ready explana-
tion of free ccntial placcntation, especially in such cases as Piimula, &c, where
not a trace of dissepiments is ever discoverable. But in Caryophyllacem the
dissepiments are often manifest. In applying it to ordinary central placcnta-
tion, we have to suppose the cohesion of the indexed margins of the carpcllaiy
leaves with a central prolongation of the axis or receptacle which bears the
placental. But in parietal placcntation, the advocates of this theory are driven
to the violent supposition that the axis divides within the compound ovary into
twice as many branches as the carpels in its composition, and that these branches
regularly adhere, in pairs, one to each margin of all the carpcllaiy leaves. Its
application is attended with still greater difficulties in the case of simple and
uncombincd pistils, where the ovules occupy the whole inner suture, which must
be taken as the typical state of the gvnrccium ; but to which the new hypothesis
can be adapted only In supposing that an ovuliferous branch of the axis enters
each carpel, and separates into two parts, one cohciing with each margin of the
metamo. phosed leaf. This \icw, however, not only appears absurd, but may
be dispioved by direct observation, as it has been most completely by those
monstrosities in which an anther is changed into a pistil, or even one part of
the anther is thus transformed and bears ovules, while the other, as well as the
filament, remains unchanged ; — a case where the ovules are far removed from
anything which can possibly belong to the axis. We may further remark, that
even the appearance of a placenta or ovulifeious body in the apparent axil of a
carpcllaiy leaf no more pioves that the body in question belongs to the axis,
than that the appendage before the petals of Parnassia and the American Lin-
den represents a branch instead of a leaf. As to the terminal naked ovule of
the Yew, where the structure, on any view, is reduced to the greatest possible
simplicity, it is surely as probable that it answers to the earliest formed, or
foliar, portion of the ultimate phyton, here alone developed, as to the aniline part,
which so seldom appears in the flower. The most iinpoitant of these points
are elucidated by Mr. Biown, in Plantcc Jamiuuc linnorcs, pp. 107-112, in
two notes, which apparently are not sufficiently studied by botanists.

296

TUli F LOW Kit.

stood : but, as it involves an erroneous idea, the expressions, Shjlcs
distinct ; united at the base ; united to the middle, or summit, &c,
as the ease may be, should be employed in preference.

559. A few casual exceptions occur to the general rule that
ovules and seeds are both produced and matured within an ovary,
namely, in a closed earpellary leaf or set of combined carpellary
loaves. In the Blue Cohodi (Caulophyllum thalietroides) the ovules
rupture the ovary soon after flowering, and the seeds become naked;
and in Mignonette they are imperfectly enclosed, the ovary being
open at the summit from an early period. In all such cases, how-
ever, the pistil is formed and the ovules are fertilized in the oidi-
nary way.

5G0. Gyntccilim of Gyiimospcrmoin Plants. A far more remarkable
exception is presented by two natural families, viz. Coniferai (Pines,

Firs, &c.) and Cycadacea3
(Cycas, Zamia). Here
ilm pistil, as likewise the
whole flower, is reduced to
the last degree of simplici-
ty ; each fertile flower con-
sisting merely of an open carpellary leaf, in place of an ordinary pistil,
in the form of a scale (Fig. 511-513, 515, 516), or of some other
shape, and bearing two or more ovules
upon pome part of its upper surface. At
the time of blossoming, these pistil-leaves
of the forming cone diverge, and the pol-
len, abundantly shed from the staminate
blossoms, falls directly upon the exposed
ovules. Afterwards the scales close over
each other until the seeds are ] ipe. In the
Yew there is no carpel or pistil-leaf at all ;
but the fertile blossom consists of a solitary
naked ovule, borne on the extremity of a

FIG 511. Scale, i e. open pistil, from the cone of a Larch at the time of flowering, or a
little later ; the upper fide seen, with its pair of naked ovules.

FIG. 512 Similar view of a Larch scale, when the seeds are partly grown. 513. A mature
scale, one of the seeds in its place, the other fallen (reduced in siie). b'A A seed detached,
with its wing

FIG 515. Branchlet of the American Arbor -Yitre, considerably larger than in nature, ter-
minated by its pistillate flowers, each consisting of a single scale (an open pistil), together
forming a small cone. 51G One of the scales or pistils removed and more enlarged, thu it;sido
exposed to view, showing a pair of naked ovules on its base.

THE OVULE.

297

short branch, and surrounded by a fcw small bracts. As the ovules
are here naked and exposed to the direct contact of the pollen, and
the seeds are not enclosed in anything answering to a pod, these
have received the name of GymkoSI'KRMOUS Plants, that is, plants
with naked seeds.

Sect. VIII. The Ovule.

561. Ovules (420, 543) are bodies borne by the pistil, which, on
being fertilized and having an embryo developed in them, become
seeds. To their formation, fertilization, and protection all the other
parts of the blossom are subservient. They vary greatly in num-
ber, from one (solitary) in each carpel or cell to a multitude. When
few and uniform in number, they are said to be definite ; when too
numerous to be readily counted, indefinite.

5G2. As to situation and direction, they are erect when they arise
from the very bottom of the cell (Fig. 518) ; ascending, when fixed
above its base and rising obliquely
upwards (Fig. 517) ; horizontal,
when they project from the side of
the cell, without turning either up-
wards or downwards (Fig. 342) ;
pendulous, when they hang or turn
obliquely downwards (Fig. 387) ;
and suspended when hanging perpendicularly from the very summit
of the cell (Fig. 519). These terms apply to the seed as well as to
the ovule.

5G3. An ovule is at first a minute projection of the placenta (Fig.
530), of soft and homogeneous parenchyma; but it soon acquires a
definite form and structure. It may be either sessile, or raised on a
stalk, the Funiculus, Podosperm, or seed-stalk. The point of
attachment, which in the seed forms the scar, is called the Hilum.

564. It consists of a kernel or nucleus, and usually of one or two
coats. The nucleus is the essential part of the organ ; in it the
embryo is formed, and the coats become the integuments of the
seed. The ovule of the Mistletoe consists of a naked nucleus only,
there being no integument. The ovule of the Walnut has oidy one

FIG. 517. Ovary of a Buttercup, divided lengthwise, to display its ascending ovule 618.
Some of Buckwheat, with an erect o\ u!e. 013 Same of Anemone, v.itli a su-pcuded ovule.

293

THE FLOWER.

coat : this appears as a circular ring around the base of the forming
nucleus, which gradually becomes cup-shaped, and at lenglh covers
it like a sac, remaining open, however, at the summit. This

orifice is called the Foramen,
or Micropyle. In far the
greater number of cases, a
second envelope is formed out-
side of the first, beginning in
the same way, though always
later than the inner one, which,
however, it eventually over-
takes and encloses. Mirbel
named the exterior coat of the
ovule the Primine, and the in-
terior the Secundine, — names which are attended with the objec-
tion that the secundine or inner coat is actually older than the
primine or exterior coat. Both sacs are open at the apex, and the
summit of the nucleus points directly towards the apertures. The
orifice or foramen of the primine or exterior integument is called
the Exostome (or outer orifice) ; that of the interior or secundine,
the Endostome (or inner orifice). The coats of the ovule and
the nucleus are distinct and unconnected, except at the base, or point
of attachment to the funiculus, where they are all confluent : this
point of union receives the name of the Chalaza (Fig. 521, d).
Through the funiculus and chalaza the ovule derives its nourish-
ment from the placenta ; through the opening at the summit, the
nucleus receives the tubular prolongation of the pollen, which incites
the formation of the embryo.

5G5. Ovules occur under four principal forms, viz. the orthotro-
pous or straight, the campylotropous or curved, the amphltropous or
half-inverted, and the anatropous or inverted. The simplest, al-
though the least common of these, is

506. The Ol'tllOtropoilS Ovule, also termed atropous (viz. not turned).
It is the form which this organ assumes in the Buckwheat family
(Fig. 518), and several others, and is likewise shown in Fig. 520,
52G, and a longitudinal section of it in Fig. 521. Here no change in

FIG. 520. An orthotropous ovule 521. Longitudinal section of the same, more magnified :
a, the primine; b, the seeundine; c, the nucleus; d, the chalaza 522 An amphitropous
ovule 523 Three anatropous ovules, with long funiculi, attached to a portion of the placenta.
524 One of the same, more highly magnified, exhibiting its cellular structure. 525. A cainp'y-
lotropous ovule.

THE OVULE. 209

the direction of parts occurs during growth ; but the base or chalaza
(Fig. 526, c) is manifestly the point of attachment, the orifice (/)
is at the opposite end, and the ovule is straight and symmetrical.

D

5G7. The Campylotropous Ovule (Fig. 525, 527) is one which grows
unequally, and consequently curves upon itself, so as to bring the
apex round to the vicinity of the base, the chalaza (c) and the orifice
(f) being at length brought nearly into contact at the point of at-
tachment. Campylotropous or curved ovules are found in the Mig-
nonette, in all Cruciferous and Caryophyllaceous plants, and in many
others.

5G8. The Annlropons Ovule (Fig. 517, 519, 523, 524, 529) is far

the most common form. It is best described by likening it to an
orthotropous ovule which as it grew had inverted itself on its funicu-
lus or support, so that, while the body remains straight, its orifice or
apex is brought down to the funiculus and points to the placenta,
while the chalaza occupies the apparent or geometrical apex, i. e. the
summit or point directly opposite the place of attachment. The
ovule, thus inverted on its support, coheres with it for ifs
whole length, and accordingly has a ridge or cord, more
or less manifest, along one side (Fig. 529, r), connect-
ing the hilum, or place of attachment, and where the
seed separates from its insertion (k), with the chalaza (c).
This cord or ridge, which morphologically is merely a
continuation of the stalk or support of the ovule adhe-
rent to its face on one side, or incorporated with it, is
called the Rhaphe. It is a distinguishing mark of an
anatropous ovule, which is also recognizable by its s:o
being straight and by having the orifice close to the point of attach-
ment. The rhaphe itself is often so incorporated with the coat of

FIG. 526 Orthotropous ovule of Buckwheat : c, hilum and chalaza ; f% orifice.
FIG. 527 Campylotropous ovule of a Chi 'kneed : c, hilum and chalaza ; /, oiifiee x,

FIG. 528. Amphitropous ovule of Mallow : /, orifice ; h, hilum ; r, rhaphe ; c, chalaza.
FIG 529 Anatropous ovule of a Violet ; the parts lettered as in the last
FIG. 530. Vertical section of a pistil of Magnolia Umbrella, from a young flower-bud, mag-
nified, showing the forming ovule, here a simple protuberance

300 FERTILIZATION.

the ovule or the seed as to be externally undistinguishable. The
seeds of Magnolia offer good illustrations of this. The mode of
formation and the internal structure of anatropous or inverted ovules
will be apparent on inspection of Fig. 530-53G.

569. The AnipllitropoilS Ovule (Fig. 522, 528), also called heterotro-
pous, differs from the anatropous in having a short rhaphe (Fig.
528, r), extending from the chalaza (c) only about half-way to the
orifice (/). It is attached accordingly by the middle of one side,
and has the chalaza at one end and the orifice at the other. It may
be regarded as a haif-anatropous or half-inverted ovule ; and all gra-
dations occur between this and the anatropous form, into which it
would pass by the cohesion of the side of the ovule with the support
a little farther down. Amphitropous ovules are general in the Mal-
low and the Primrose families. As such an ovule stands with its
axis at right angles with the funiculus, if there be any, it is also said
to be transverse.

570. Most of these terms apply to seeds as well as to ovules ; and
the general structure of the seed may be known beforehand from
that of the ovules. We are now prepared to contemplate the pro-
cess by which an ovule becomes a teed.

Sect. IX. Fertilization and Formation of the Embryo.

571. In order to the formation of the embryo (118), the ovules
require to be fertilized by the pollen. Ca.-,es of parthenogenesis,
i. e. of the formation of perfect seed without the agency of pollen,
doubtless do sometimes occur, and have been noted in several

FIG. 531 A similar side-view of the ovule of the last, a week or two later, and more mag-
nified ; showing the nucleus encircled by the coats in formation, as two rings or shallow cups
one within the other. 032 The same a few days later, more advanced and beginning to turn.
633 The same, further advanced 534. The same, soon after, with the inversion almost
complete, and the outer coat covering the inner, except at the oriSce 535 The completed
anatropous ovule rom a full-grown flower-bud. 636 A longitudinal seetiou of the same,
displacing the rhaphe, the fcrfO co..tj, and the nucleus.

THE ACCESS OF THE POLLEN. 301

dioecious plants. More than half a century ago, Spallanzani found
that the pistillate blossoms of Hemp may produce fertile seed with-
out the concurrence of pollen ; and recently Naudin and Deeaisne
have confirmed the fact by experiment, and from seeds produced
without fertilization have raised a second generation of plants, the
pistillate individuals of which, kept from all access of pollen, have
themselves ripened seeds with perfect embryos.* Two or three
dioecious P^uphorbiaceous plants are known to produce good seed
under the same circumstances, and Naudin has shown it freely to
occur in Bryony. Still these are very exceptional cases, and are all
confined, so far as known, to dioecious plants. Ordinarily the access
of pollen of the species to the ovules is necessary to the production
of the embryo.

572. The Access of the Pollen to the pistil is secured in a great
variety of ways and adaptations. In hermaphrodite blossoms the
relative length and position of the stamens and stigmas are conv
monly so adjusted that the pollen may fall directly upon the
stigma, the anthers being usually higher than the stigmas when
the flower is upright, and shorter when it is nodding. Sometimes
pollen is projected upon the stigma by transient and often sudden
movements, either mechanical, as in Kalmia, or spontaneous and
vital, as in the Barberry (to be mentioned in another place). Some-
times fertilization takes place in the bud, where the parts are in
apposition, or the anthers are kept in contact with or proximity to
the stigma, as in papilionaceous flowers by the enclosing keel-petals,
and in the Fumitory family by a close-fitting little sac formed of the
united spoon-shaped tips of the two inner petals confining the an-
thers to the stigma. Very often the pollen is conveyed from the
anthers to the stigma by insects, searching for honey or nectar ; and
there are many species in which fertilization seems absolutely to
depend upon the agency of insects ; such, for instance, as those of
Aristolochia, Asclepias or Milkweed, and many plants of the Orchis
family. In dioecious and many monoecious plants, with widely sep-
arated blossoms, fertilization is mainly dependent upon insects, pass-
ing from flower to flower, and upon winds and currents. And the
immense quantity of pollen which many such plants produce com-
pensates for the greater distance of the passage, and greatly dimin-
ishes the chance of failure. The air of a Pine forest in flowering-

* Comptes Rendu*, Vol 43, 1856, and Hooker's Journal of Botany, 1857, p. 53.
2G

302

FERTILIZATION'.

time is almost loaded with pollen, some of which is often wafted by
the winds for many miles.

573. The pollen of Pines and other Gymnospermous plants falls
directly upon the naked and exposed ovules (5 GO). On all others,
the ovules, being secluded in a closed ovary, can be fertilized only
through the stigma. In these, accordingly, we have first to con-
sider.

574. The Action of Men on the Stigma. The loose papill-e, or

often the short projecting hairs of the stigma, and the moist surface,
serve to retain the grains of pollen on the stigma when they have
once reached it. Absorbing some of this moisture, and nourished
by it, the grains of pollen which are favorably situated soon begin
to grow, or, as we may say, to germinate. The thin inner mem-
brane (534) extends, breaks through the thicker, but weak or brittle,
outer coat at some point (or rarely at two or three places), and
lengthens into a delicate tube, filled with the liquid and molecular
matter that the grain contains. This tube ( Fig. 537-540), remain-
ing closed at the extremity, penetrates the loose tissue of the stigma,
and is prolonged downwards into the style, gliding along the inter-
spaces between the very loosely disposed cells of the moist conduct-
ing tissue (541), which extends from the stigma to the cavity of the
ovary, and at length reaches the placenta,
or fome other part of the lining of the
ovary, and its extremity appears in the
cell. This prolongation into a tube, often
many hundred times the diameter of the
pollen-grain, is a true growth, after the man-
ner of elongating cells (37 - 97), nourished
by the organizable moisture of the style
which it imbibes in its course. Now the
orifice of the ovules, or a projection of
the nucleus beyond the orifice, is at this
time brought into contact with, or close
proximity to, that portion of the walls of the ovary from which the
pollen-tubes project ; and a pollen-tube thus enters the orifice of
each ovule, and reaches the nucleus, in which the nascent embryo

TIG. 537. A pollen-grain of Datura. Stramonium, emitting its tube. 538. Pollen-grain of
a Convolvulus, with its tube. 539 Other pollen-grains, with-fcieir tubes, less strongly mag
nified 5-10. A pollen-grain of the Evening Priimcwc, resting on a portion of the stigma, into
which the tube emitted from one of the angles penetrates ; the t>ppo.-ite angle also emitting a
pollen-tube.

THK ACTION OF THE POI.LKN.

303

subsequently appears. In Gymnospermous plants (5 GO, .573), the
pollen-grains grow at the orifice of the naked ovule, and immediately
penetrate its nucleus, just as they do the stigma in ordinary plants.

575. Pollen-tubes may be readily inspected under the microscope
in many plants ; in none more readily than in the Asclepias, or
Milkweed, one of the plants in which this subject was so admirably
investigated by Mr. Brown. In that family, the pollen-grains of
each cell of the anther (Fig. 541) cohere in a mass ; and these
pollen-masses, dislodged from their cells (Fig. 542, 543), usually by
the agency of insects, and brought into proximity with the base of
the stigma, protrude their tubes in great abundance. They may be
seen to penetrate the base of the stigma, as in Fig. 544, and sepa-
rate grains with their tubes may be detached from the mass (Fig.
546, 547) ; but to trace their course down the style (as in Fig. 545),
and to their final destination, requires much skill in manipulation
and the best means' of research.

576. The formation of the pollen-tube commences in some cases
almost immediately 5n 542 513 M1
upon the applica-
tion of the pollen
to the stigma ; in
others it is not per-
ceptible until after
the lapse of from ten
to thirty-six hours
or more. The rate

of the growth of the I ^iMMM^ ^ ^^^I'li^r;:;::';]/ (I //

pollen-tube down
the style is al?o
very various in dif-
ferent plants. In
some species, a week or more elapses before they have passed
through a style even of a few lines in length. In others, a few

FIG 541 -A back view of a stamen of the common Milkweed (Asclepias), the appendnge
cut away. 542 A stamen more magnified, with the two pollen-musses cohering by their cau-
ilicles, each to a glaud from the summit of the stigmatic body, to which a pollen-mass from an
adjacent anther is already adherent 543. A pair of detached pollen-masses (each from a dif-
ferent anther) suspended by their caudicles from the gland. 544. Some of the pollen-masses,
with their tubes penetrating the stigma (after Brown). 545 A section through the large stig-
matic body and a part of the summit of one of the styles, showing the course of the pollen-
tubes. 54G. 547 Pollen-grains with their tubes, highly magnified (The structure of the»«
6iugular flowers will bo more fully explained under the order Asclepiailacea.)

304 FERTILIZATION.

horn's suffice for their passage through even the longest styles, such
as those of Colchicum, Mirabilis or Four-o'clock, and Cereus grandi-
florus. After the pollen-tubes have penetrated the stigma, the latter
dries up, and its tissue begins to wither or die away, as likewise
does the body of the pollen-grain, its whole contents being trans-
ferred to the pollen-tube, the lower part of which may still be in a
growing condition.

577. Before the pollen-tube has reached the ovule, or more com-
monly even before the pollen is applied to the stigma, a cavity ap-
pears in the interior of the nucleus of the ovule, near its apex.
This probably results from the special growth of a particular cell,
which expands into a bladder or closed sac, at length commonly oc-
cupying a considerable part of the nucleus, — sometimes remaining
enclosed in its tissue towards its summit or orifice, sometimes dis-
placing the upper part of the nucleus entirely, or even projecting
through the micropyle. This is the sac of the amnios of Mr. Brown,
the embryo-sac (sac embryonaire) of the French botanists. In this
sac the embryo is formed.

578. Origin of 1 lie Embryo. From the latter part of the seven-
teenth century, when the relative functions of the stamens and the
pistils, and something of the structure of the ovule, were demon-
strated by Malpighi, Grew, &c, until about the year 1837, it was
almost universally supposed that the embryo was a product of the
ovule, in some way incited or fertilized by the pollen. One writer,
viz. Samuel Morland, had indeed propounded the crude hypothesis,
that a pollen-grain itself, descending bodily through the style, was
received into the orifice of the ovule, and became the embryo. The
absurdity of this view was soon made evident. But how the pollen
acted was wholly unknown until Amici, in 1823, discovered pollen-
tubes, penetrating the stigma, and Brongniart, Brown, Amici himself,
and Schleiden, within the ensuing twelve or fourteen years, had
demonstrated their universality, and traced these slender tubes into
the ovary, and even to the nucleus of the ovule. Then commenced a
spirited controversy, which has only just now been brought to a close.
For Professor Schleiden, in the year 1837, advanced the view that the
extremity of the tube of the pollen, entering the nucleus of the ovule,
there developed into the embryo, — thus anew deriving the embryo
or new plant substantially from the pollen instead of the ovule.
This view has recently been abandoned by its indefatigable author
and his mo it able supporter, Schacht, having been thoroughly dis-

.ORIGIN OF THE EMBRYO. 305

proved in all points by a series of elaborate investigations made by
Mirbel, Amici, Giraud, Mold, Hofmeister, Unger, Tulasne, Ilenfrey,
and Radlkofer. So that — passing by the whole history of this long
discussion, and merely appending some references to the more im-
portant publications upon the subject * — we need only state here,
in the most general terms, the principal facts which are now held
to be established, viz.: —

579. The pollen-tube terminates on the outer surface of the
embryo-sac, or sometimes, perhaps, forces its way into it. Ordina-
rily its extremity becomes firmly adherent to the surface of the
embryo-sac, and it appears to remain closed. Ilenfrey, indeed, is
led to suppose that the membrane of the pollen-tube and that of the
embryo-sac are absorbed at the point of contact, and that the former
thus discharges its contents into the cavity of the latter ; but this is
merely an unproved inference, suggested by the analogy of what is
now known of the process of fecundation in Cryptogamous plants.
At present it appeal's most probable that the contents of the pollen-
tube are drawn into the embryo-sac by endosmosis. However this
may be, shortly after reaching the embryo-sac the pollen-tube be-
comes empty, and decays or withers away. Meanwhile the body
which by its development is to give rise to the embryo appears in
the embryo-sac independent of the pollen-tube. According to most
investigators it generally appears before the pollen-tube has entered
the ovule. (The high authority of Tulasne, however, is thus far

* Schlcidcn first published his famous theory in Wiegmann's Arehiv, 1837,
and in Acta Nova Acad. Nat. Cur., Vol. 19. It was extended and defended in
his systematic works, — and especially by Schacht in Tram. Netherlands Insti-
tute, 1850, in Bol. Zeitung, 1855 (transl in Ann. Sci. Nat. of that year), in his
Beitiiir/e Anat. §• Phi/s., in his work on the microscope, of which an Engli.-h
translation by Dr Currcy was published in 1855, and in the Rcgensberg
Flora, 1855 (Ann. Sri. Nat. 1855). Sec also Dcecke in Hot. Zeihtng, 18f.5
{Ann. Sri. Nat., 1 c ) On the other side of the question the most important of
the recent publications, since the appearance of Mold's Principles of the Anatomy
and Phys.o'o'jy of the Va/etable Cell, in the English translation (1852), and tho
article Ovule in the Miaor/iapluc Dictionary by Ilenfrey, arc : Hofmeister, in
Flora, May, 1855, and Mold, in Dot Ze.itung, June, 1855 (both reproduced in
Ann. Sci. Nat., ser. 4, Vol 3, 1855); Tulasne, in Ann Si. Nat., scr. 4, Vol 4,
1855, being the complement of his great memoir published in the same journal
(scr. 3, Vol. 12, 1849) ; Radlkofer, Die Brfruchtunrj der Plianmy/amien, Lcipsic,
1S56 ; Ilenfrey, Development of the Ovule of SanUilum lubuia, &c , in Trans. Linn.
Soc., Vol. 22, part 1, 1856.

2G*

306

FERTILIZATION.

opposed to the pre-existencc) It is a small mass or globule of pro-
toplasmic matter, either loose in the cavity of the embryo-sac near
the place to which the pollen-tube is applied externally, or else ad-
herent to the interior surface of the wall of the embryo-sac in this
immediate vicinity, or sometimes separated from the embryo-sac by
an interposed globule, or by a pair of such globules. This body, the
rudiment of the future embryo, has been termed the embryonal or
germinal vesicle. This is not yet a
cell ; for it has no covering or wall
of cellulose. But it soon becomes
one when a pollen-tube reaches the
embryo-sac, the first known result of
fertilization being that a coat of cel-
lulose is deposited upon its surface.
This newly-formed cell grows by
cell-multiplication (33), either pro-
ducing a mass of cells, as shown in
Fig. 10-14, or else in the first place
developing into an elongated cell or
a thread-shaped chain of cells (the
suspenior), the lower cell of which
divides in all directions, forming a
mass, which as it grows shapes itself
into the embryo (Fig. 549-553).
The radicle or root-end of the em-
bryo is always that by which it is
attached to the suspensor (which
ordinarily soon disappears) or to the
summit of the embryo-sac, the coty-
ledons occupying the opposite ex-
tremity. The radicle accordingly
is always directed to the orittce or
micropyle of the ovule and seed.
580. Through the fertilization of as many germinal vesicles, two
or more embryos are frequently found in the same seed, in the
Orange, the Onion, and many other plants. There are generally

FIG 548 Magnified pistil of Buckwheat; the ovary and ovule divided lengthwise: some
pollen on the stigmas, one grain distinctly showing its tube, which has penetrated the. st) 1b,
reappeared in the cavity of the ovary, entered the mouth of the orthotropous ovule (o), and
reached the cmbr^o-sac (s) near the embryonal vesicle (e).

FORMATION OF THE EMBRYO.

307

two embryos in the seed of the Mistletoe ; and there is usually a
plurality of embryos in Pines and other Gymnospermous plants
(560), though all but one 519 550 551 532 553

are more commonly abor-
tive or rudimentary. There
arc other striking peculiar-
ities in the fecundation of
Tines, &c, which, however,
cannot be readily explained without
entering into more detail than is
here advisable.* In Tines and their
allies, moreover, the embryo is not
developed until a long time after the
application of the pollen, and the
fdling of the embryo-sac with the

cellular tissue which forms the basis of the albumen of the seed ;

the fruit and seed of
true Tines, as is well
known, not maturing un-
til the year after that
in which the blossoms
appear.

580'. The further development and the structure of the embryo
and the seed* must be considered after the Fruit, of which it consti-
tutes a part.

a

* Sec Hofmcistcr, Untersucftungen, &c : Researches into the Fertilization, &c.
of the higher Cryptogamia and the Coniferaj (Lcipsie, 1851), with seven plates
devoted to the embryology of Coniferaj.

FIG. 549 Dingram of the suspensor and forming embryo nt its extremity. 550 The same,
■with the embrjo a little more developed. 551. The same, more developed still, the cotyledons
faintly indicated at the lower end. 552. Same, with the incipient cotyledons more manifest.
653. The embrjo nearly completed.

FIG 554 - 556. Forming embryo from a half-grown seed of Buckwheat, in thrw jtages.
557. Same, with th« cotyledons fully developed.

S08

THE KIR- IT.

CHAPTER X

OF THE FRUIT.

Sect. I. Its Structure, Transformations, and Dehiscence.

581. The fertilized ovary, increased in size, and usually under-
going some change in texture and Ibrm, becomes

582. The Pericarp, or Sccd-USSCl. The pericarp and the seeds it
contains together constitute the Fruit ; a term -which has a more
extensive signification in botanical than in ordinary language, being
applied to all mature pistils, of whatever form, size, or texture. To
the fruit likewise belongs whatever organs may be adnate to the
pistils (4G8). Such incorporated parts, like the fleshy calyx of the

Apple and Quince (Fig. 809, 812), sometimes
make up the principal bulk of the fruit.

583. Indeed, the calyx, when wholly free
from the pistil, sometimes becomes greatly
thickened and pulpy after flowering, and is
transformed into what appears like a berry ;
as in Gaultheria (Fig. 913), where the real
fruit is a dry pod within; and in* Strawberry
Blite (Fig. 1099), where the fleshy calyxes of
a head of flowers each surround a small seed-
like fruit, and together form a false multiple
fruit, resembling a strawberry.

584. Even the strawberry itself is not a
fruit in the strict botanical sense : that is, the
edible substance is not a ripened pistil, nor a
cluster of pistils, but is the receptacle or ex-
tremity of the flower-stalk, greatly enlarged
and replete with delicious juice ; the true fruits
being the minute and seed-like ripened ovaries
scattered over its surface ; as plainly appears

from a comparison of Fig. 558 with 559. Moreover, a mulberry,

FIG. 558 A'ertical section of a forming strawberry, enlarged.
FIG. 559. Similar section of one half of a ripe strawberry, auj of i
like fruits, or acheuia, on its surface.

i of the small seed-

ITS STRUCTURE AND TRANSFORMATIONS. 309

a fig, and a pine-apple consist of the ripened products of many
flowers, crowded on an axis or common receptacle, which makes a
part of the edible mass.

585. Under the general name of fruit, therefore, even as the word
is used by the botanists, things of very different structure or of dif-
ferent degrees of complexity are confounded. We must distinguish,
therefore, between simple fruits, resulting from a single flower, and
a multiple fruit, resulting from the parts of more than one flower
combined or collected into a mass. We must also distinguish be-
tween true fruits, formed of a matured pistil, either alone or with a
calyx, &c. adnate to it, and fruits, so called, of which the pericarp
does not form an essential part.

586. Obliteration or Alteration. The pericarp, being merely the
pistil matured, should accord in structure with the latter, and con-
tain no organs or parts that do not exist in the fertilized ovary.
Some alterations, however, often take place during the growth of
the fruit, in consequence of the abortion or obliteration of parts.
Thus, the ovary of the Oak consists of three cells, with a pair of
ovules in each; but the acorn, or ripened fruit, presents a single
cell, filled with a solitary seed. In this case, only one ovule is
matured, and two cells and five ovules are suppressed. The ovary
of the Horsechestnut and Buckeye is similar in structure (Fig.
777 -780), and seldom ripens more than one or two seeds ; but the
abortive seeds and cells may be detected in the ripe fruit. The
ovary of the Birch and of the Elm is two-celled, with a single ovule
in each cell : the fruit is one-celled, with a solitary seed ; one of the
ovules or young seeds being uniformly abortive, while the other in
enlarging thrusts the dissepiment to one side, so as gradually to ob-
literate the empty cell ; and similar instances of suppression in the
fruit of parts actually extant in the ovary are not uncommon. On
the other hand, there are sometimes more cells in the fruit than
properly belong to the pistil. For instance, the ovary of Datura
Stramonium is two-celled ; but the fruit soon becomes spuriously
four-celled by a false partition connecting each placenta with the
dorsal suture. So the compound ovary of Flax when young is five-
celled, but with a strong projection from the back of each cell (Fig.
500) which at maturity divides the cell info two, thus rendering
the fruit ten-celled. And some legumes are divided transversely
into several cells, although the ovary was one-celled with a continu-
ous cavity in the flower.

310 THE FRUIT.

587. Ripening. The pericarp sometimes remains herbaceous in
texture, like the pea-pod, or becomes thin, dry, and membranaceous,
like the pod of the Bladder-Senna. In such cases it is furnished
with stomates, continues to have chlorophyll in its cells, and acts
upon the air like an ordinary leaf. In other plants the pericarp
thickens, and either becomes hard and dry, like a nut, or else fleshy
or pulpy, like a berry (gooseberry, grape, &c). Sometimes the
outer portion softens into flesh or pulp, while the inner portion hard-
ens, thus forming a stone-fruit, like the cherry and peach.

587'. Most fleshy or pulpy fruits are tasteless or slightly bitter
during their early growth ; at which period their structure and
chemical composition are similar to that of leaves, consisting of cel-
lular with some woody tissue ; and their action upon the atmosphere
is likewise the same (34G). In their second stage, they become
sour, from the production of acids (353) ; such as tartaric acid in
the grape ; the citric, in the lemon, orange, and the cranberry ; the
malic, in the apple, gooseberry, &c. At this period they exhale very
little oxygen, or even absorb that substance from the surrounding
air. The acid increases until the fruit begins to ripen, when it grad-
ually diminishes, and sugar is formed. In the third stage, or that of
ripening,, the acids, as well as the fibrous and cellular tissues, gradu-
ally diminish as the quantity of sugar increases ; the latter being
produced partly at the expense of the former. A chemical change,
similar to that of ripening, takes place when the green fruits are
cooked ; the acid and the mucilaginous or other products, by the aid
of heat reacting upon each other, are both converted into sugar.
Mingled with the saccharine matter, a large quantity of vegetable
jelly (83) is also produced in most acidulated pulpy fruits, ex-
isting in the form of pectine and pectic acid. These arise from
the reaction of the vegetable acids during ripening upon the dex-
trine and other ternary products accumulated in the fruit.

588. When the walls of a pericarp form two or more layers of
dissimilar texture, the outer layer is called the JUpicarp, the middle
one, Mesocarp, and the innermost, Endocarp. A stone-fruit or
drupe, like the peach, consists of two layers, viz. the outer or fleshy
layer, which is therefore termed the Sareocarp, and the inner, or
endocarp, the shell or stone, which is also termed the Putamen.

589. Fruits afco may be divided into the indehisccnt or closed, and
the dehiscent or those that open. Fleshy fruits generally, stone-
fruits, and many dry fruits, especially one-seeded ones, such as nuts,

ITS KINDS. 311

achenia, &c, remain indehiscent ; -while most pods or capsules dehisce
at maturity.

590. Some pods burst irregularly when ripe and dry ; others open
and shed their seeds by definite pores, as the Poppy, or by larger
holes, chinks, or valves, as the Campanula, Snapdragon, &c. ; or by
a transverse line cutting off the top of the pod, as in Henbane and
Purslane. These arc modes of irregular dehiscence. But

501. Dehiscence, when regular and normal, is effected by a vertical
separation or splitting, viz. by the opening of one or botli sutures of the
ovary (543), or, in a fruit resulting from a compound ovary (548),
by the disjunction of the united parts. The several modes of dehis-
cence will be characterized under the kinds of fruit in which they
occur (G07-G14).

Sect. II. The Kinds of Fruit.

592. The various kinds of fruits have been minutely classified
and named ; but the terms in ordinary use are not very numerous.
A rigorously exact and particular classification, discriminating be-
tween the fruits derived from simple and from compound pistils, or
between those with and without an adnate calyx, becomes too recon-
dite and technical for practical purposes. It is neither convenient
nor philosophical to give a substantive name to every variation of
the same organ. For all ordinary purposes it will suffice to char-
acterize the principal kinds under the four classes of Simple, Aggre-
gate, Accessory or Anthocarpous, and Multiple Fruits.

593. Simple FruilS are those which result from the ripening of a
single pistil, whether with or without a calyx or other parts adnate
to it. This division comprises mo?t of the kinds of fruit which have
distinctive names, and those of the other classes are mainly aggre-
gations or combinations of these.

594. Simple Fruits may be conveniently divided into Fleshy
fruits, Stone fruits, and Dry fruits. The leading kind of the
first division is

595. The Berry (Bacca), an indehiscent fruit which is fleshy or
pulpy throughout. The grape, gooseberry, currant, cranberry, and
tomato are familiar examples.

596. The Ilcspcriuium (orange, lemon, and lime) is merely a berry
with a leathery rind.

312

THE FRUIT.

597. Till Ffpo, or Gourd-fruit, is also a modification of tlie berry,
with a hard rind, which occurs in the Gourd family. The cucum-
ber, melon, and squash are familiar illustrations. A Pepo is an
indehiscent, externally firm and internally pulpy fruit, composed
usually of three carpels, and with an adnate calyx. In the ovary it
is either one-celled with three broad and revolute parietal placenta?,
or these placenta;, borne on slender dissepiments, meet in the axis,
enlarge, and spread, unite with their fellows on each side, and are
reflected to the walls of the pericarp, next which they bear their
ovules (Fig. 5G0, 561). As the fruit enlarges, the seed-bearing
placenta? usually cohere with the
walls, and the partitions are oblit-
erated, giving the appearance of
a peculiar abnormal placentation,
which only the study of the ovary
readily explains.

598. A Pome, such as the apple,
pear, and quince (Fig. 809, 812),
is a fruit composed of two or more
carpels, either papery, cartilagi-
nous, or bony, usually more or less
involved in a pulpy expansion of
the receptacle or disk, and the
whole invested by the thickened and succulent tube of the calyx.
It may be readily understood by comparing a ro e-hip with an apple.
The calyx makes the princi-
pal thickness of the flesh of
the apple, and the whole of
that of the quince".

599. The Drupe, or Stone-

Fruit, is a one-celled, one or
two seeded indehiscent fruit,
with the inner part of the peri-
carp {endocarp, or putameji,
588) hard or bony, while the outer (erocarp, ov sarcocarp) is fleshy
or pulpy It is the latter which in these fruits so readily takes
an increased development in cultivation. The name is strictly

FIG. 560. Section of the ovary of the Gourd 561. Diagram of one of its constituent carpels.

FIG 562. Vertical section of a peach. 563 An almond ; where the exocarp, the portion
of the pericarp that represents the pulp of the peach, remains thiu and juiceless, and at
leDgth separates by dehiscence from the endocarp, or shell.

ITS KINDS.

313

566-573).

applicable only to fruits produced by the ripening of a one-celled
pistil; as the plum, peach (Fig. 562), &c. ; but it is extended in a
general way to such fruits with two or more bony
cells enclosed in pulp, as that of the Dogwood, &c.

600. The raspberry and blackberry (Fig. 564)
are composed of a great number of miniature stone-
fruits, or drupelets, as they might be called, in struc-
ture resembling cherries (Fig. 565), aggregated upon
an elongated receptacle.

601. Dry Fruits may be either dehiscent or indehis-
cent (589). Of indehiscent dry fruits one of the
simplest kinds is

602. The Achenium, or Akenc (Fig.

This includes all one-
seeded, dry and hard,
indehiscent and seed-
like, small fruits, such as
are popularly taken for
naked seeds. But that
they are true pistils or
ovaries ripened is evident from the styles or stigmas they bear, or
from the scar left hy their fall ; and a
section brings to view the seed within,
provided with its own proper integuments.
The name has been restricted to the seed-
like fruits of simple pistils, as those of
the Buttercup (Fig. 566, 567), Anemone,
Clematis, and Geum (where the persist-

FTG. 564. Magnified rertical section of half of a blackberry. 505. Section of one cf th«
grains, or drupettts, more magnified.

FIG. 5G6 Achenium of a common Buttercup, enlarged. 507. Vertical section of the same,
showing the seed within

FIG. 6G8 Achenium of Mayweed (no pappus) 569 That of Cichory (its pappus a shal-
low cup). 670 Of Sunflower (pappus of two deciduous scales) 571 Of Sneezcwecd (Ilele-
nium) with its pappus of five scales 672. Of Sow-Thistle, with its pappus of delicate downy
hairs. 573 Of the Dandelion, its pappus raised on a long beak.

27

314

THE FRUIT.

ent style usually remains on the fruit as a long tail), and the minute
grains of the strawberry (Fig. 559). But it may be extended, as
is now generally done, to all such one-celled seed-like fruits result-
ing from a compound ovary, and even when invested with an adnate
calyx-tube. Of this kind is the fruit of all Composite (Fig. 568-
573). Here the tube of the calyx is incorporated with the surface
of the ovary, and its limb or border, obsolete in some cases (Fig.
568), in others appears as a crotvn (Fig. 560), cup, a set of teeth
or of scales (Fig. 570, 571), or as a tuft of bristles or hairs (Fig.
572, 573), &c, called the pappus. In the Lettuce and Dandelion
(Fig. 573), the achenium is rostrate, i. c. its summit is extended
into a slender beak.

/ 603. A Utricle is the same as an achenium, only with a thin and
bladdery loose pericarp, like that of Goosefoot and
Amaranth (Fig. 574, 575). The thin coat commonly
bursts irregularly, discharging the seed. In the true
Amaranths it opens by a circular line, and the upper
part falls as a lid, converting the fruit into a small
pyxis (619).

604. A Caryopsis or Grain differs from the last in hav-
ing the seed completely filling the cell, and its coat
firmly consolidated throughout with the very thin peri-
carp, as in wheat, Indian corn, and other cereal grains
(Fig. 622-624). Of all fruits this is the kind most
likely to be mistaken for a seed.

605. A Nut is a hard, one-celled and one-seeded, indehiscent fruit,
like an achenium, but larger, and usually produced
from an ovary of two or more cells with one or more
ovules in each, all but a single ovule and cell having
disappeared during its growth (586) ; as in the
Hazel, Beech, Oak (Fig. 576, 1166), Chestnut,
Cocoa-nut, &c. The nut is often enclosed or sur-
rounded by a kind of involucre, termed a Cupule ;
as the cup at the base of the acorn, the bur of the
chestnut, and the leaf-like covering of the hazel-nut.

606. A Samara or Kcy-frilit is a name applied to a nut, or achenium,
having a winged apex or margin ; as in the Birch, Elm (Fig. 578),

FTG. 574 Utricle of Chenopodium album, or common Goosefoot. 575 Utricle, or pyxis,
of an Amaranth
FIG. 57C. Acorn (uut) of White Oak, with its cup or cupule.

ITS KINDS.

315

and Ash (Fig. 577). The fruit of the Maple consists of two such
fruits belonging to one flower, united by their bases (Fig. 787).

607. Dehiscent Fruits, or Pods, are distinguishable into
those consisting of a simple pistil, and thoie resulting
from a compound pistil.

608. Of those originating from simple pistils, the
principal kinds are the Follicle and the Legume. These
may be taken as the type, of simple fruits.

609. A Follicle is a pod formed of a simple pistil, and
dehiscent by the ventral or inner suture alone ; as in

the Milkweed, Larkspur, Columbine, Peony,
and Marsh-Marigold (Fig. 579). When it
opens widely, the pistil may be said to revert
to its natural state of a leaf, and it often looks
much like one, as in Fig. 492.

610. A Legume is a pod formed by the ripen-

579 ing of a simple pistil which dehisces by both

sutures, and so divides into two valves or pieces, as in

the Bean and Pea (Fig. 580). This being the ordinary

fruit of the Pulse family, accordingly named
Leguminosce (or Leguminous plants), the name
has been extended to it in descriptive botany,
in all cases, whatever the form, and whether
dehiscent or not. The legume will be found
to exhibit no small diversity in this large fam-
ily (799). Among its forms is one termed

611. A LoillCUt. This is a legume divided
transversely into two or more one-seeded joints,
which usually fall apart at maturity (Fig. 581).
Commonly these joints remain closed, as in
Dcsmodium ; sometimes they split into two
valves, as in Mimosa,

612. A Capsule is the pod, or dehiscent fruit,
of any compound pistil. When regularly dehis-
cent, as already stated (591), the pod splits
lengthwise into pieces or valves.

613. A capsule, necessarily consisting of two or more carpels or

FIG 577 Samara of White Ash. 578 Samara of American Elm.

FIG 579 Folli. !c of Caltha palustris, the Marsh-Marigold

FIG 5S0. Legume of a Sweet Pea, already dehuceut 581. Loment of a Tick-Trefoil or
Desmodiuui.

316

TIIK FRUIT.

simple pistils united into one body, will normally dehisce in one
of two ways. Namely, either the carpels will separate at the line
of junction, thus resolving the pod into its constituent
elements ; or else, these parts remaining united, each
cell will open on the back by a splitting of the dorsal
suture. The former constitutes

614. Scpticidal Dehiscence (Fig. ,582,
584), so named because the capsule splits
through the septa or partitions (dissepi-
ments), each one separating into its two
constituent layers, one belonging to each
carpel. This occurs in Azalea and its
allies, in St. Johnswort, &c. The car-
pels, thus becoming separate, in these
cases open down their inner suture,
like a follicle, and discharge the seeds. 583

When the cells are only one-seeded, after separating septicidally,

they often remain closed

and fall away separately,

as in Mallow, Vervain (Fig.

985), &c. Such closed or

nearly closed cells or car-
pels of a compound pistil

are termed cocci.

615. Loculicidal Dehis-
cence is that in which the splitting opens into the loculamcnts (in
Latin, loculi) or cells ; that is, each carpel dehisces by its dorsal
suture (Fig. 583, 585), as in Iris, the Lily, Hibiscus, Evening Prim-
rose, &c. The dissepiments here are necessarily borne on the mid-
dle of the valves.

616. In the Violet, &c. we have the loculicidal, and in several
kinds of St. Johnswort the septicidal, plan of dehiscence in one-
celled capsules ; the placenta; (answering to the partitions) being
borne in the former upon the middle of the valves ; while in the
latter each placenta is split in two, and one half borne on each mar-
gin of a valve.

TIG 5S2. Dehiscent capsule of Elodea, enlarged, shoeing septicidal dehiscence.
FIG 583 Dehiscent capsule of Iris, showing loculicidal dehiscence ; the lower part cut
across, showing the dissepiments borne on the u:iddle of the valves

FIG. 384. Diagram (in cross-section) of septicidal, and, 5S5, of loculicidal, dehiscence.

ITS KINDS.

317

617. Scptifragal Dehiscence is a modifica ion of either the loculicidal
or the septicidal, in which the valves fall away, leaving the dissepi-
ments behind attached to the
axis. Fig. 586 is a diagram
representing this in a case
of loculicidal opening. Fig.
587, from the common Morn-
ing-Glory, is Phis modifica-
tion of the septicidal mode.

G18. Instead of splitting 5S7

into separate pieces, the sutures of the pericarp sometimes open for
a short distance at their apex only, as in Cerastium and some other
Chickweeds, in Tobacco (Fig. 1050), and in the Primrose (Fig
943) ; or by mere pores, as in the Poppy. The pod of the Snap-
dragon opens by the bursting of a hole towards the top of each cell,
not corresponding, perhaps, with any suture. Another anomalous
mode of dehiscence, namely, the circumcissile, characterizes

619. The lyxis or Pyxidium, a pod which opens by a circular hor-
izontal line cutting off the upper part as a lid. The
fruits of the Plantain, Henbane, Amaranth (Fig.
575, which is otherwise a utricle), Pimpernel, and
Purslane (Fig. 588) are of this kind.

620. A Silique is a slender two-valved capsule, with
two parietal placenta;, from which the
valves separate in dehiscence ; as^ in
plants of the Cruciferous or Mustard
family (Fig. 589), to the fruit of which the term prop-
erly belongs. Usually a false partition is stretched
across between the two placenta?, rendering the pod
two-celled in an anomalous manner.

621. A Silicle or Pouch is merely a short silique, its
length not more than twice its breadth ; as that of Shep-
herd's-Purse, Candytuft, &c.

622. Aggregate Fl'UitS are those in which a cluster of
carpels, all belonging to one flower, are crowded on the 589
receptacle into one mass, as in the raspberry and blackberry taken
as a whole (Fig. 564), where the constituent fruits, or ripened carpels,

FIG. 586. Septifragal modification of loculicidal, and. 587. of septicidal, dehiscence.
FIG. 688. P\ xis or pod of Purslane, the top separating as a, lid.
IIG. 589 Silique of Cardamine, iu dehiscence.

27*

318 THE FRUIT.

are little drupes ; al-o the cone-like fleshy fruit of Magnolia, where
the component carpels are a sort of drupaceous follicles; at length
opening on the back and summit ; and the dry cone of the Tulip-tree,
■where each carpel forms a sort of samara. None of these aggregate
fruits have special names in ordinary use. In descriptive botany it
is sufficient to state the kind of fruit the carpels themselves form,
and their mode or degree of aggregation.

G23. Accessory or Anlliocarpous Fruits are those of which the most
conspicuous portion, although often appearing like a pericarp, neither
belongs to the pistil nor is organically united with it. The apparent
berry of Gaultheria, in which a succulent free calyx invests a dry
pod and appears to form the real fruit (Fig. 912-914) has already
been adverted to (583) ; and the calyx of Shepherdia is similar,
forming what appears to be the sarcocarp of a drupe, although it is
really free from the achenium it encloses. So, also, the apparent
achenium or nut of Mirabilis, or Four-o'clock, is the thickened and
indurated base of the tube of a free calyx, which contracts at the
apex and encloses the true pericarp as a utricle or thin achenium,
but does not cohere with it. The rose-hip, a hollow calyx-tube
lined with a hollow receptacle (Fig. 429), and the strawberry (Fig.
428, 558, 559), consisting of a conical enlarged receptacle bearing
many minute achenia, may aLo be regarded as forms of anthocar-
pous fruit.

G24. Multiple cr Collective Fruits are those which result from the
aggregation of several flowers into one mass. The simplest of these
are those of the Fart ridge-Berry (Mitchella) and of some species of
Honeysuckle (Fig. 859), consisting of the ovaries of two blossoms
united into one double berry. The more usual sorts are such as the
pine-apple, mulberry, and the fig. These are, in fact, dense forms
of inflorescence, with the fruits or floral envelopes matted together
or coherent with each other ; and all or some of the parts become
succulent. The grains of the mulberry (Fig. 593, 594) are not the
ovaries of a single flower, like those of the blackberry which it super-
ficially resembles (Fig. 5G4), but belong to as many separate flow-
ers ; and the pulp of these pertains to the floral envelopes instead of
the pericarp. So that the mulberry is an anthocarpous (623) as
well as a multiple fruit. The pine-apple is very similar ; only the
ovaries or pericarps never ripen any seed-, but all are blended, with
the floral envelopes, the bracts, and the axis of the stem they thickly
cover, into o:ie fleshy and juicy mass. The fig (Fig. 590 -592)

ITS KINDS. 319

differs from the pine-apple in having this succulent axis ov receptacle

on the outside. It may be compared with such an anthocarpous
fruit as a rose-hip (Fig. 429). It results from a multitude of flow-
ers concealed in a hollow flower-stalk, if it
may be so called, which becomes pulpy and
edible when ripe; and thus the fruit seems
to grow directly from the axil of a leaf,
without being preceded by a blossom. The
minute flowers concealed within, or some of
them, ripen their ova-
ries into very small
achenia, which arc
commonly taken for
seeds. The principal
form of multiple fruit
which has received a
substantive name is
625. The Strobile or Cone, a scaly multiple fruit, resulting from the

FIG 590 A young fig. 591. Vertical section of the prime, enlarged 592. A small slice of
the same, more magnified, showing the flowers on the inside.

FIG 593 A j oung mulberry 594 One of the grains, magnified, showing it to be a pis-
tillate flower, -with a succulent calyx embracing the ovary 595. The same, less magnified, the
eucculent calyx cut away.

FIG 596 Strobile or Cone of a Pitch Tine. Pinus rigida. 597. Inside view of one of the
scales, showing one of the seeds, and the place from which the other, 59S, has been detached.

320

THE SEED.

ripening of some sort of catkin. The name is applied to the fruit of
the Hop, where the large and thin scales are bracts ; but it more
especially belongs to the Pine or Fir cone, the peculiar fruit of Co-
niferae (Fig. 59G), the scales of which are open carpels (5 GO), bear-
ing two or more naked seeds upon their upper or inner face (Fig,
597). A more or less fleshy and closed cone, such as that of Taxo*
dium, and especially that of Juniper (Savin, Red Cedar, &c), which
at maturity imitates a berry, has been termed a Galualus.

CHAPTER XI.

OF THE SEED.

Sect. I. Its Structure axd Parts.

C2G. The Seed, like the ovule (561), of which it is the fertilized
and matured state, consists of a Nucleus, or kernel, usually en-
closed within two Integuments.

627. lis Integuments, &C The outer, or
proper seed-coat, corresponding to the ex-
terior coat of the ovule, is variously termed
the Ei'isperm, Spermoderm, or more com-
monly the Testa (Fig. 599, b). It varies
greatly in texture, from membranaceous or
papery to crustaceous or bony (as in the
Papaw, Nutmeg, &c), and also in form, being sometimes closely
applied (conformed) to the nucleus, and in other cases loo.?.o and
cellular (as in Pyrola, Fig. 927, and Sullivantia, Fig. 843), or ex-
panded into wings (as in the Catalpa and Trumpet-Creeper, Fig.
G01), which render the seeds buoyant, and facilitate their dispersion
by the wind ; whence winged seeds are oidy met with in dehiscent
fruits. The wing of the seed of Pines (Fig. 598) is a part of the
surface of the scale or carpel to which it is attached, and which
separates with it. For the same purpose, the testa is sometimes

FIG- 599. Vertical magnified section of the (anatropous) seed of the American Linden : a,
the hilum ; 6, the testa ; c, the tegmen ; il, the albumen ; e, thd embr. o GOO. Vertical section
of the (orthotropous) seed of Ilelianthemum Canadeuse . a, the funiculus.

ITS STRUCTURE AND TARTS. 321

provided with a tuft of hairs at one end, termed a Coma ; as in
Epilobium and Milkweed (Fig. G02). In the Cotton-plant, the
whole surface of the seed is covered with long wool.
It should likewise be noticed, that the integument of
numerous small seeds is furnished with a
coating of small hairs containing spiral
threads (one form of which is represented
in Fig. 44), and usually appressed and con-
fined to the surface by a film of mucilage.
When the seed is moistened, the mucilage
softens, and these hairs spread in every
direction. They are often ruptured, and 601

the extremely attenuated elastic threads they contain uncoil, and are
protruded in the greatest abundance and to a very considerable length.
This minute mechanism subserves an obvious purpose in fixing
these small seeds to the moist soil upon which they lodge, when dis-
persed by the wind. Under the microscope, these tlu-eads may be
observed on the seeds- of most Polemoniaccous plants, and on the
achenia of Labiate and Composite plants, as, for example, in many
species of Senecio, or Groundsel. In Peony the testa becomes
fleshy or baccate ; in Magnolia it. imitates a drupe.

628. The inner integument of the seed, called the Tegmen or
Endopleura, although frequently very obvious (as in Fig. 599, c),
is often indistinguishable from its being coherent with the testa, and
is sometimes altogether wanting.

629. The stalk of the seed, as of the ovule, is called the Fu-
niculus (Fig. 600, a). The scar left on the face of the seed, by its
separation from the funiculus at maturity, is termed ihe Hiluxi.
The chalaza and rhaphe, when present, are commonly obvious in
the mature seed, as well as in the ovule (564-568), and the name
and relations of these several parts in the seed are the same as in
the ovule. Also the terms orthotropons, anatropous, camjyylotropous,
•fee, originally applied to the ovules, are extended to the seeds which
result from them ; so that Ave may say, Seeds anatropous, as well as
Ovules anatropous, &c.

630. Aril or Al'illllS. Some seeds are furnished with a covering,
(usually incomplete and of a fleshy texture,) wholly exterior to their
proper integuments, arising from an expansion of the apex of the

FIG. 601. The winged seed of Trumpet-Creeper.

FIG. 602. Seed of Milkweed (Asckpioa Cornuti), with its coma or tuft.

322 tii :■: s::::n.

seed-stalk, or funiculus, or of the placenta itself when there is no
manifest seed-stalk. This is called the Aril. It forms the pulpy
envelope of the seed of Podophyllum, Euonymus, and Co-
lastrus, or it appears as a mere lateral scale in Turnera, or
as a tough and lacerated body, known by the name of mace,
in the Nutmeg. In the White Water-Lily it is a thin and
delicate cellular bag, open at the end (Fig. GOG). The
Aril does not appear in the ovule, but is developed subso-
603 quent to fertilization, during the growth of the seed. Of
the same or similar nature is the Caruncle found at the hiluin ia
Polygala, forming a loo-e lateral appendage. Strictly speaking, it
is to be distinguished from the Stkoi'hiolk (like that of Euphor-
bia), which is a cellular growth from the raicropyle ; but the two are
not Avell discriminated. An analogous cellular growth takes place
on the rhaphe of (he Bloodroot, of the Prickly Poppy, and of Dicen-
tra, forming a conspicuous crest on the whole side of the seed.

031. The Nucleus, or Kernel of the seed, consists of the Albumen,
when this substance is present, and the Embryo.

G32. The Albumen, which has also been termed the Perisperm or
the Endosperm, has already been described (125) as the iloury part
of those seeds in which an amount of nourishment for the germi-
nating plantlct is stored up outside of the embryo. This was
called by Gnertner the albumen of the seed, from some fancied anal-
ogy with the white of an egg as to situation or function ; — an un-
fortunate term, on account of its liability to be confounded with the
quaternary chemical substance of the same name (357), one of tha
forms of proteine. Being in general use, the term cannot r.ow well
be discarded.

033. The Albumen of the seed consists of whatever portion of the
tissue of the ovule persists, and becomes loaded with nutritive mat-
ter accumulated in its cells, — sometimes in the form of starch-
grains principally, as in wheat and the other cereal grains ; some-
times as a continuous, often dense, incrusting deposit, as in the cocoa-
nut, the date, the coffee-grain, &c. When it consists chiefly of
starch-grains, .and may readily be broken down into a powder, it is
said to ha farinaceous, or mealy, as in the cereal grains generally, in
buckwheat, &c. When a fixed oil is largely mixed with this, it
becomes oily, as in the seed of the Poppy, &c. ; when more compact,
but still capable of being readily cut with a knife, it is fleshy, as in

FIG. 603 A seed of the White Water-Lily, with its sac-like arillus, magnified.

T1IK ALBUMKN AND EMBRYO.

323

the Barberry, &c. ; when it chiefly consists of mucilage or vegetable
jelly, as in the Morning-Glory and the Mallow, it is said to be muci-
laginous ; when it hardens more, and becomes dense and tough, so
as to offer much resistance to the knife, as in the Coffee, the Blue
Cohosh, &c, it is corneous, that is, of the texture of horn. Between
these all gradations occur. Commonly the albumen is a uniform
deposit. But in the nutmeg, as also in the seeds of the Papaw (Fig.
658), and of all plants of the Custard-Apple Family, it presents a
wrinkled or variegated appearance, owing to numerous transverse
divisions, which are probably caused by inflections of the innermost
integument of the seed : in these cases the albumen is said to be rumi-
nated. The albumen may originate from new tissue formed either
within the embryo-sac (579), which is probably the more common
case ; or in the nucleus of the ovule exterior to the embryo-sac,
which is certainly the case in the "Water-Lily and its allies, and in
Saururua ; for here the thickened embryo-sac persists within or at
one extremity of the copious albumen ; or both kinds may coexist.
"When this is the case, the outer albumen may be distinguished as the
perisperm, and the inner as the endosperm.

G34. Seeds provided with albumen (as in Fig. 599, GOO, G05, 606,
609, 610 -GIG, 622, &c.) are said to be albuminous; those destitute
of it (as in Fig. G07, G29, 110, 120, &c.) are exalbuminous. The
comparative amount of the albumen, and its relation to the embryo
in various seeds, may be seen on inspection of many of the subjoined
figures.

635. The Embryo, cr Germ, being an initial plantlet or individual, is
of course the most important part of the seed : to its production, protcc-

FIG. 604 SipJ of a Violet (anatropous), enlarged: a, hilum or scar ; 6, rhaphe ; c, chalaza.

MO. 605 Vertical sectioa of the same, showing the straight embryo in the axis of the mealy
albumen.

FIG. 606 Vertical section of the (orthotropous) seed of Buckwheat, showing the embryo
folded round in the mealy albumen.

FIG. 607. Vertical section of the (anatropous) seed of Flodea Virglnica, tie embryo com-
pletely filling the coats

FIG. 608 Seed of Delphinium tiicorne (anatropous), enlarged; n, the hilum ; *, the
rhaphc ; c the chalaza. 609. Vertical section of the same : c, the chalaza ; </, the testa ; e,
the tegmen ; /, the albumen ; g, the minute embryo near the hilum, a.

324

TIIK SEKD.

tion, and support all the other parts of the fruit and flower are sub-
servient. It becomes a plant by the mere development of its parts :
it therefore possesses, in a rudimentary or undeveloped state, all the
essential organs of vegeiation, namely, a root, stem, and leaves. Its
general structure and development have already been explained in
considerable detail (118 - 130).

636. In albuminous seeds it is naturally the smaller and its parts
the less developed in proportion to the amount of albumen, and the

several organs are
developed or even
formed in germina-
tion. In exalbumi-
nous seeds, where
the embryo con-
stitutes the whole
kernel, its several
parts are ordina-
rily conspicuous,
although they are
often more or less disguised by thickening; as the cotyledons in
the Almond (Fig. 108) and Cherry (Fig. Ill), and especially in
the Pea (Fig. 118), the Acorn (Fig. 120), the Ilorsechestnut (Fig.
630), and the like.

G37. The parts of the embryo, as already illus-
trated (120) are the Radicle, the Cotyledons, and
the Plumule. The radicle is the axis, or rudimen-
tary stem, — the first internode of the axis (121,
157), from the lower extremity of which lhe root
is produced, while the other bears the cotyledons,
i. c. the leaves of the iirst node ; and the plumule 6is m

is lhe bud which crowns the summit of the radicle.

G38. Owing to the mode of its formation (-380), the radicle of the

FIG 610. Vertical section of the seed of a Peony, showing a small embrj o near the base of
the copious albumen. Gil. The embryo, detached, and more magnified.

FIG C12. Section of a seed of Barberry, with a straight embryo in the axis of tho albu-
men G13. Its embryo, detached.

FIG. 614. Section of a Potato-seed, showing the embryo coiled in the albumen. 615. Its
embryo, detached

FIG 616 Section of the seed of Mirabilis or Four-o'clock, showing the embryo coiled round
the outside of the albumen. G17. Its embryo, detached, and partly spread out.

FIG 618 Embryo of the Pumpkin, with its short radicle and large and flat cotyledons,
seen flatwise. 610. A vertical section of the same, viewed edgewise.

THE KMUUYO.

325

embryo is always near to and points towards the micropyle of the
seed, viz. to what was the orifice of the ovule; and if the embryo be
straight (as in Fig. 605), or merely partakes of the curvature of
the seed, the cotyledons point to the opposite extremity of the seed,
that is, to the chalaza. The position of the radicle as respects the
hilum varies with the different kind of seed. In the orthotropous
form, as in Helianthemum (Fig. GOO) and Buckwheat (Fig. GOG),
the radicle necessarily points directly away from the hilum. In the
anatropous form, as in the seed of the Lin-
den (Fig. 599) and Violet (Fig. 604, 605),
the extremity of the radicle is brought to
the immediate vicinity of the hilum ; and
so it is, although in a different -way in
the campylotropous seed (Fig. G20, 621) ; while in the amphitro-
pous, the radicle points away from the hilum laterally, at a right
angle to the funiculus. As the nature of the ovule and seed may
usually be ascertained by external inspection, so therefore the situa-
tion of the embryo within, and of its parts, may often be inferred
without dissection. But the dissection of seeds is not generally a
difficult operation.

G39. The position of the embryo as respects the albumen, when
that is present, is various. Although more commonly in the axis, it
is often excentric, or even external to the albumen, as in all Grasses
and cereal Grains (Fig. 622-624), in Polygonum (Fig. 1111), &c.
When external or nearly so, and curved circularly around the albu-

men, as in Goosefoot, Chickweed (Fig. 621), and Mirabilis (Fig.
616), it is said to be peripheric. When bent or folded in such a

FIG. C20. Campylotropous seed of the common Chickweed (Stellaria media), magnified.

FIG. 621 Section of the same, showing the embryo coiled around the outside of albumen.

FIG. 622. Vertical section of a grain of Indian Corn, passing through the embryo : c the
cotyledon ; p, the plumule ; r, the radicle. (A highly magnified portion of the albumen, which
makes up the principal bulk of the grain, is shown in Fig. 70, p. 54.) 623. Similar section of
a grain of Rice. 624. Vertical section of an Oat-grain : a, the albumen ; c, the cotyledon ; p,
the plumule ; and r, the radicle of tho embryo.

28

326 the seed.

way that the radicle lies along the edges of the cotyledons, the
latter are said to be decumbent (Fig. 700) ; or when the radicle
rests against the back of one of them, or in proximity to it (Fig.
705), they are incumbent.

G40. The direction of the embryo with respect to the pericarp is
also particularly noticed by systematic writers ; who employ the
terms ascending, or radicle superior, when the latter points to the
apex of the fruit ; descending, or radicle inferior, when it points to
its base ; centripetal, when the radicle is turned towards the axis
of the fruit ; centrifugal, when turned towards the sides ; and vague,
when it bears no evident or uniform relation of the kind to the
pericarp.

641. As to the number of its cotyledons, or the degree of com-
plexity or simplicity of the embryo, the principal types have already
been considered (128). The plan of the embryo in Exogenous
plants is to have a pair of opposite cotyledons ; that is, the embryo
is dicotyledonous, and such plants are denominated Dicotyledo-
nous Plants.

642. A modification of this plan occurs in Pines and most other
Conifera?, in which the cotyledons are increased to three, four, six,
or even to fifteen, in a whorl (Fig: 133, 134) ; and this embryo of
highest complexity is called polycotyledonous. The embryos of
some Leguminous or Cruciferous plants are occasionally found, with
three cotyledons, as an accidental deviation.

643. But in all Endogenous plants only one cotyledon appeal's,
i. e. only one seed-leaf on the primary node ; if two or more rudi-
mentary leaves are present, they are alternate, and all but the first

belong to the plumule. Here the em-
bryo is monocotyledonous, and hence
Endogens are also termed Moxocotv-
ledonous Plants. The monocoty-
ledonous embryo does not usually pre-
sent a manifest distinction into radicle,
cotyledons, and plumule, as the dicoty-
ledonous ; but often appeai-s like a ho-
mogeneous and undivided cylindrical or club-shaped body, as in Iris

FIG. 625 Seed of Triglochin pnlustre ; the rhaphe, leading to the strong ehalaza at the
summit, turned towards the eye. 626. The embryo detached from the seed-coats, showing
the longitudinal chink at the base of the cotyledon ; the short part below is the radicle. 627.
Same, with the chink turned laterally, and half the cotj ledon cut away, bringing to view the
plumule concealed within. 628 A cross- section through the plumule, more magnified.

THE EMBRYO.

327

(Fig. 131) and Triglochin (Fig. C2G). In the latter, however, close
inspection reveals a vertical slit or chink just above the radicular
extremity, through which the plumule is protruded in germination.
If the embryo be divided parallel with this slit, the plumule is
brought into view ; as in Fig. 627. If a horizontal section be made
at this point (as in Fig. 628), the cotyledon is found to be wrapped
around the enclosed plumule, sheathing it, much as the bud and the
younger parts of the stem are sheathed by the bases of the leaves
in most monocotyledonous plants. The plumule is more manifest
in Grasses, especially in the cereal grains, and more complex, ex-
hibiting the rudiments of several concentric leaves, or of a strong
bud, previous to germination (Fig. 622-624, and 126-128). In
many cases, however, no distinction of parts is apparent until ger-
mination commences ; as in the Onion, Iris (Fig. 131), &c.

644. In several Dicotyledonous plants one cotyledon is smaller,
than the other, viz. the inner one, when the embryo is coiled oi
folded. And in all the species of

Abronia this cotyledon is wanting,
so that the embryo becomes tech-
nically monocotyledonous. In
the Dodder, a genus of leafless
parasitic plants of the Convolvu-
lus family, the embryo also is
entirely destitute of cotyledons
(Fig. 148). Here these organs
are suppressed in an embryo of
considerable size ; but in most
such parasites, the embryo is very
minute, as well as reduced to the
greatest degree of simplicity, and
seems to remain until germination
in a very rudimentary state.

645. Sometimes the two cotyle-
dons of a dicotyledonous embryo
are consolidated, or more or less
coherent by their contiguous faces

into one mass, when they are said to be conferritminate, as in the
Horsechestnut, Buckeye (Fig. 629, 630), and the Chestnut. In
these, as in other embryos with very thick cotyledons, the la.tter are

FIG 629 Section of t'je Leedof a I'.uckeye 600. A Euckeye in germination.

328 THE SEED.

necessarily hypogceous in germination (124, 12G), that is, they re-
main underground, enclosed within the coats of the seed, yielding
their abundant store of nourishment to the radicle and the plumule ;
and the first leaves that appear are those of the plumule.

Sect. II. Germination.

646. Germination is the initial act of growth, by which the embryo
in a seed develops into a plantlet. The steps of the early growth
have already been sufficiently explained in an early part of this vol-
ume (119-132).

647. The seeds of some plants (such as the Red Maple) germi-
nate shortly after falling to the ground ; those of most other plants
not until the next year, or even later. How long seeds may retain
the power of germinating is uncertain, and is extremely variable in
different species and families. Those of many plants under ordinary
circumstances can rarely be made to grow after two or three years ;
some will germinate pretty well after several years keeping ; and
the seeds of certain Leguminous plants have been known to germi-
nate when sixty years old. But the current accounts of wheat, &c.
being raised from grain taken from ancient mummies, circumstan-
tially authenticated as some of them appear to be, must be received
with the greatest misgiving, if not with entire incredulity. One of
the most probable cases of germination of ancient seeds on record is
that given by Dr. Lindley, of some Raspberries, " raised in the gar-
den of the Horticultural Society from seeds taken from the stomach
of a man, whose skeleton was found thirty feet beloAV the surface of
the earth, at the bottom of a barrow which was opened near Dorches-
ter. He had been buried with some coins of the Emperor Hadrian ;
and it is therefore probable that the seeds were sixteen or seventeen
hundred years old." Most seeds, when buried deep in the soil,
where they are subject to a uniform and moderate temperature, and
removed from the influence of the air and light, may be in a favorable
state for the preservation of vitality, and would be likely to germi-
nate when brought to the surface after a considerable interval. But
the possibility of mistake or of collusion must be more thoroughly
eliminated before a case of such extraordinary tenacity of life, under
conditions in some respects very unfavorable, can be considered as
well established.

GERMINATION. 329

G48. The conditions requisite to germination are exposure to
moisture and to a certain amount of heat, varying from 50° to 80°
(Fahrenheit) for the plants of temperate climates, to which must be
added a free communication with the air. Direct light, so essential
to subsequent vegetation, is unnecessary, and generally unfavorable,
to germination. The degree of heat required to excite the latent
vitality of the embryo is nearly uniform in the same species, but
widely different in different plants ; since the common Chickweed
will germinate at a temperature not far above the freezing-point of
water, while the seeds of many tropical plants require a heat of
90° to 110° (Fahrenheit) to call them into action, and are often
exposed to a considerably higher temperature. Seeds are in the
most favorable condition for germination in spring or summer, when
loosely covered with soil, which excludes the light while it freely
admits the air, moistened by showers, and warmed by the rays of
the sun. The water which is slowly absorbed softens all parts of
the seed ; the embryo swells, and bursts its envelopes, or the elon-
gating radicle is protruded from them, and all the parts grow or
unfold in the manner already described, each organ in its proper
medium, the root being developed in the soil, and the stem and
leaves in the air.

G49. The nourishment which the embryo requires during germi-
nation is furnished by the starch, &c. of the albumen (6a2), when
this substance is present in the seed ; or by starchy or other nutri-
tive matter accumulated in its own tissue (G36, 123). But as starch
is insoluble in cold water, certain chemical changes are necessary to
bring it into a fluid state, so that it may nourish the embryo. These
changes are incited by the proteine or neutral azotized products
(354), which are largely accumulated in the seed, either in the
albumen or in the embryo itself, and which take the initiative in all
the transformations of vegetable matter (27). In the germinating
seed, just as in growth from a bulb or tuber, the changes essentially
consist in the transformation of the starch, first into dextrine, or
gum, and thence into sugar, a part of which is destroyed by resolu-
tion, first into acetic acid, and finally into carbonic acid and water,
with the abstraction of oxygen from the air, and the evolution of
heat (349, 370 - 373), while the remainder is rendered directly sub-
servient to the growth of the plantlet. The reason why light, so
essential to subsequent growth, impedes or prevents incipient ger-
mination, becomes evident when we remember that it incites the
28*

330 RKPRODUCTION I*

decomposition of carbonic acid, and lh-^ fixator* e^ carbon by tbe
plant (344 - 350) : while germination is necessarily attended by an
opposite transformation, namely, the destruction of a portion of or-
ganized matter, with tbe evolution of carbonic acid.* In germina-
tion, as in any other act in which matter is transformed or trans-
ferred, there is a certain expenditure of force and loss of organized
material. The plantlet is obliged to decompose and destroy a part
of the starch or other material provided for its initial growth, in
order that it may transform the rest into dextrine and sugar, and
this again into cellulose or the material of the new cells formed in
its growth.

G50. The study of the seed, and of the development of the em-
bryo it contains into a plantlet, completes the cycle of vegetable life
in the higher grade of Phamogamous plants, and brings us back to
our starting-point (118, 110).

CHAPTER XII.

OP REPRODUCTION IN CRYPTOGAMOUS OR FLOWERLESS PLANTS.

G51. The lower grade of Ckyptogamous oh Flowerless
Plants (Chap. II. Sect. I.) would now require to be considered,
bo:h as to the vegetation and their reproduction. But the plan of
structure in each principal Cryptogamous family is so peculiar,
and the organs of fructification especially so diverse, that their
morphology cannot be i^resented under one common type, as in Pha>
nogamous vegetation. Each great family or group would have to
be separately treated, and with much fulness of illustration, to make

* Seeds may casually germinate while attached to the parent plant, especially
such as are surrounded with pulp, like those of the Cucumber and Melon The
pioccss is liable to commence in wheat and othei grain, when protracted warm
and rainy weather occurs at the period of ripening ; and the albumen becomes
glutinous and sweet, from the partial transformation of the starch into dextrine
and sugar. In the Mangrove, which forms dense thickets along tiopical coasts,
germination habitually commences in the pericarp while the fruit remains on the
tree ; and the radicle, piercing the integuments which enclose it, elongates in the
air; such a plant being, as it were, vivipaious.

CRYl'TOGAJIOUS Oil FJLOWERtKSS 1'LAXTS. 331

the subject intelligible to the unpractised student. This can hardly
be done in so elementary a work as the present, but requires a sepa-
rate treatise. The student who has intelligently studied the present
volume up to the present point, is prepared for the more difficult study
of the structure of Cryptogamous plants, in the only general work of
the kind that has yet appeared in the English language, viz. Berke-
ley's Introduction to Cryptogamic Botamj. An enumeration of the
Cryptogamous orders, with a brief notice of their structure and sub-
ordinate divisions, may be found in the systematic part of the pres-
ent work. A slight sketch of their grades of development as to
vegetation has already been given (97-113). We here attempt
to present merely a very brief and general account of their plan of
reproduction, divested as far as possible of technical terms.

652. Taken collectively, we distinguish this lower series of the
vegetable kingdom by negative characters only ; saying that these
plants do not bear true flowers (consisting essentially of stamens and
pistils), and accordingly do not produce seeds, or bodies consisting
of a distinguishable embryo plantlet, developed in an ovule through
fertilization by pollen. Their spores (97), or the bodies produced in
their fructification by which they are propagated, and which there-
fore answer to seeds, are single cells, at least in most cases. These,
as they germinate in the soil, or whatever medium they live in, un-
dergo a development at the time of their germination which has been
compared with that of the embryonal vesicle (579) during its devel-
opment into the embryo in the ovule ; and by growth directly give
rise to the plant.

G53. It was once thought probable, that the^e spores were pro-
duced, and were capable of developing into the plant without being
fertilized by other cells answering to pollen ; or at least that this was
the case in all the lower orders, such as Alga? and Fungi, and in some
of the highest, such as Ferns. But the sagacious Linnams, by nam-
ing them Cryptogamous plants (i. e. plants with concealed organs of
reproduction) seems to have recorded his belief that they were really
bisexual, or furnished with two sorts of organs, the fertilizing and the
fertilized. A series of important discoveries, for the most part of
recent date, have proved this to be so, — have made known a true
fecundation in numerous species of every Cryptogamous order, and
in their lowest as well as their highest forms, thus leaving no doubt
of its universality. The apparatus and the processes of reproduction,
however, are wonderfully varied in the different groups of Cryp-

332

REPRODUCTION IN

togamous plants. A few examples may be adduced, illustrative ot
the principal modes, beginning with the simplest plants.

6o4. Reproduction in Plants of a Single Cell (100). All such simple

one-celled plants as Protococcus and the like (Fig. 79-83, 18 - 22),
Desmidiaceai and Diatomacea?, are freely propagated by cell-multi-
plication (33 - 3G), — the division of their protoplasm or whole living
mass into bodies Avhich directly become new cells like the parent, —
or by original cell-formation in their interior (29). This is non-
sexual reproduction, and essentially answers to the well-known prop-
agation of Phamogamous plants by buds, bulbs, offsets, &c. It is
probable that this may not go on indefinitely in any plant. At any
rate, not only do all the higher plants propagate in a different way,
viz. by flowers, producing seeds, but probably all plants of the lower
grade also have a sexual reproduction in some form or other. It is
certainly the case in many one-celled plants, and in others almost
equally simple in structure. As in Phamogamous plants, sexual
reproduction essentially depends upon the mingling of the materials ,
of two distinct cells (as the pollen-cell and the embryonal vesicle,
579) ; and these cells in the lowest forms of vegetation represent
individual plants. The simplest mode of such reproduction in the
lowest plants, and that longest known, is what has been termed

Goo. Conjugation. This is the mode in which two vast tribes of
microscopic one-celled aquatic plants, the Desmidiaceae and Diato-
macea?, are reproduced. They midti-
phj rapidly, and apparently without
limit, by successive division into two
equal parts, which separate, each be-
coming like the original. But at length
two of these individuals, being en-
dowed with the power of movement,
come into contact ; the firm or often
silicious cell-wall ruptures or gives
way in a definite manner at the place
of junction, and the whole contents of
the two conjugating cells or individu-
als are commingled into one mass of
protoplasm, &c. ; this soon has a coat of cellulose formed around it,

FIG 631. Magnified individual of Closterium acutum, after Italfs. 632. Two individuals
more magnified, in conjugation ; their cells opening one into the other, and the contents min-
gled j in 633, condensinz ; in C34, collected and formed into a spore.

CItYPTOGAMOUS OR FLOWERLESS PLANTS.

333

and is now a spore, which when it grows begins a new series of in-
dividuals developed by successive division.

656. In Alga: consisting of a Single Row of Cells one tribe presents

the same mode of reproduction, and the various species of Zygnema
or Spirogyra, found in almost every pool of fresh
water at different times in spring and summer,
afford the readiest illustrations of conjugation,
which low powers of the microscope suffice to
exhibit. The^e green threads when magnified
are seen to consist of single rows of cylindrical
cells joined end to end. The cells being all
alike and equally capable of conjugation, each is
as it were an individual. At a certain season,
a protuberance appears on the corresponding
parts of certain cells of two adjacent threads;
the budding growth continues until the two
come into contact ; the intervening walls are
then absorbed, opening a free communication
between the cavities of the two cells ; mean-
while the green matter and protoplasm, before
arranged in some definite shape in each species
(more commonly in one or more spiral bands),
break up into a granular mass floating in the
water of the cell ; this all passes over from one

cell to the other, — sometimes to the one plant and sometimes to the
other in adjacent cells, — and is mingled with the similar contents of
the cell which receives it ; and the united product is condensed into
a green protoplasmic mass, which, acquiring a coat of cellulose, be-
comes a new cell or spore, in due time germinating into a new plant.

657. In reproduction by conjugation, the two cells or individuals
concerned are alike ; one is as much the fertilizer or the fertilized
as the other. But the clear distinction of sexes which all the higher
Cryptogamous no less than Phrenogamous plants exhibit, is also mani-
fested in those of the simplest structure, viz. in plants consisting of
single cells, or of rows or clusters of similar and essentially inde-
pendent cells. That is, even these afford examples of

FIG 635. Magnified view of two conjugating filaments of Zygnema, showing all the stages
of the process by which the cells from two filaments form each a corresponding protuberance,
these come into contact, the intervening walls are absorbed, and the contents pass from one
cell into the other, condense, acquire an investing membrane, and so form a spore : the stages
are represented from above downwards ; a completed spore is seen at the bottom, on the right

334 RKPKODCCJION IN

658. Cii-ect Fertilization of Spores by Spermatozoids from an Anllic-
ridilim ; the latter answering to the anther, or essential part of the
stamen, of Phaenogamons plants. Cohn * has shown that even
Yolvox — an undoubted vegetable, consisting of microscopic one-
celled plants of rounded form, grouped into a spherical colony — has
a true sexual propagation, like that of the higher green Alga;, some
of the individuals or cells of the sphere producing antheridia or fer-
tilizing cells, while others produce spores, or bodies which become
such on being fertilized by the antheridia, which alone renders them
capable of germination. A good general idea of bisexual reproduction
in the simplest Algne may best be obtained from a brief abstract of
what lias lately been discovered by Pringsheim and Cohn in two or
three common species of comparatively easy investigation.

659. Vaucheria is a genus of several species of green Algre, con-
sisting of simple but indefinitely branching cells (Fig. 89). In fruc-
tification, the whole contents of the more or less enlarged extremity
of some of the brandies, or of a special projection from the side
of the cell, separate from the general contents of the plant, con-
dense into a globular green mass (Fig. 89 a), and become a spore,
which at length escapes by a rupture of the Avails (Fig. 90), moves
freely about in the water for some hours, then fixes itself, and ger-
minates, elongating directly into a thread-like and at length branch-
ing plant, like the parent. Here there appeal's, and was generally
thought to be, reproduction without fecundation. Yaucher, however,
more than half a century ago, noticed one or more horn-shaped pro-
jections in the vicinity of the spore-bearing portion, which he sus-
pected to be the analogues of the anther. Nothing had been found
to verify this view until the year 1854, when Pringsheim, of Berlin,
discovered the fecundation and verified this conjecture. The horn-
shaped body is an antheridium, or the analogue of the anther. It
produces myriads of extremely minute corpuscles, of oblong shape,
and furnished with a bristle or cilia at each end, by the vibration of
which they move freely in the water. These are spermatozoids (so
called from their obvious resemblance to the spermatozoa of ani-
mal:,), and the analogues of pollen. At the proper time the anthe-
ridium bursts at the summit, and discharges the spermatozoids ; at
this time the wall of the projection which contains the spore likewise
opens ; numbers of the free-moving spermatozoidi find their way

* In Comptes IZcndus, vol 43, 1856, and Ann Sci. Nat. scr. 4, vol. 5, p. 323.

CKYPTOGAMOCS OK FLOWJCRLKSS TLANTS. 335

into the opening and into contact with the forming spore, or even
penetrate its substance ; it being an amorphous mass, coated with
protoplasm only. But, as a consequence of fecundation by one or
more spermatozoids, a wall of cellulose is presently formed on its
surface, converting it into a proper specialized cell or spore.*

GGO. iEdogonium is a genus of simple Alg;e of the Conferva tribe,
consisting of a row of cylindrical cells placed end to end, as in Fig.
639. Some of these cells, usually shorter than the rest, become
tumid, and, without conjugation, have their whole green contents
transformed into a spore resembling that of Zygnema (Fig. 635)
and Vaucheria (Fig. 90). The fertilization of this spore has re-
cently been discovered by Pringsheim.f He ascertained that other
cells of the same little plant produce a great number of minute
ovoid bodies, which he names Androspores : these escape by the
opening of the mother cell, moving about freely by the vibration of a
crown of cilia attached near the smaller end. One or more of these
androspores fix themselves by the smaller end upon the surface of
the cell in which a large ordinary spore is forming, or in the vicinity,
and germinate there, growing longer and narrower at the point of
attachment, while near the free end a cross partition forms, and some-
times another, making one or two small cells ; this is the true anthe-
ridiuni ; for in it a crowd of spermatozoids are formed, also endowed
with motivity by means of vibratile cilia. Now the top of the an-
theridium falls off as a lid, the spermatozoids escape ; the spore-cell
at this time opens at the top ; one of the spermatozoids enters the
opening, its pointed end foremost ; this becomes stationary upon or
slightly penetrates the surface of the young spore, into which its
contents are j>robably transferred, by rupture or by endosmos-is, and
a coat of cellulose is then, but not till then, deposited upon it, com-
pleting its organization as a spore. This spore, as in the preceding
cases, in due time germinates, and grows directly into a plant like
the parent. But in Bolboehrete, according to Pringsheim, and in
Sphneroplea, as investigated by Cohn,J the spore in germination
converts its contents by successive division into a large number of
small, oval or oblong bodies, furnished with two long cilia on a short

* Pringsheim, in the Proceedings of the Royal Academy of Sciences, Berlin,
March, 1855, and Ann Sci. Nat. scr. 4, vol. 3, p. 363.

t Op. supra cit. May, 1856, and Ann. Sci Nat. scr. 4, vol. 5, p. 250.
t Op. supra cit May, 1855, and Ann. Sci Nat' I c. p. 186, pi. 12, 13.

336 REPRODUCTION IX

beak at one end, and which from their extreme resemblance to ani-
malcules and their lively movements are called Zoospores. And
these zoospores germinate by elongation and the formation of trans-
verse partitions into adult thread-like plants, consisting of a row of
cells. The whole contents of the cells of some adult individuals of
Sphajroplea are formed into large green spores, as yet without a coat ;
those of different individuals give rise to myriads of slender sperma-
tozoids, moving by means of a pair of cilia fixed at the narrow end.
These escape from the parent cell through a small perforation which
now appears, enter the spore-bearing cells of the fertile plant
through a similar perforation, play around the spores, and at length
one or more of them drives its pointed extremity into their naked
surface ; after which, fertilization being accomplished, a thick coat
of cellulose is deposited to complete the spore.

GG1. That in the Fucaeea? or olive-green Seaweeds, the highest
tribe of Alga;, the large spores are fecundated by spermatozoids, or
minute lively-moving cells produced in antheridia, was demonstrated
by Thuret in the year 1850.* And in more recent memoirs f he
has shown that the fertilization takes place through direct contact of
the spermatozoids with the naked surface of the unimpregnated spore,
then having only a protoplasmic coating ; and that these spores will
not develop unless so fertilized. Through the researches of Thuret
and others, antheridia are now well known in the remaining or
rose-red series of Alga?, although their spermatozoids are not known
to be endowed with motivity. The same appears to be the case with
Lichens, the bodies described by Itsigsohn,J being probably of the
nature of spermatozoids or fertilizing cells. In the vast family of
Fungi there are similar indications of antheridia and spermatozoids,
but the fecundation is not yet clearly made out.

G62. Fertilization by Spermatozoids of a Cell in a Pis'.ilidium, which
becomes a Sporangium. In all the foregoing cases, the spores them-
selves are the subjects of direct fertilization. But in Mosses,'
Liverworts, &c. (in which the two kinds of organs have long been
recognized and their functions to some extent understood), the
contents of the antheridium act upon an organ which, in conse-

* Ann. Sci. Nut. scr. 3, vol. 14 ami 16, 1850-1. See Harvey, Nereis Bor.-
Atner. in Smithsonian Contributions, 1852, &c.
t Op. cit ser 4, vol. 2 and 3, 1854, 1855.
J In Botamsche Z.itumj, 1850.

CUYPTOGAMOUS OR FLO WEIILESS "PLANTS. 337

quence of fertilization, develops into a sort of pod, the Sporangium
or Spwe-case, tilled with a multitude of spores which receive no in-
dividual fecundation ; this organ, from its general analogy to the
pistil, has been termed a Pistillidium. The anlheridia of Mosses
and the like occur either in the axils of the leaves, or collected
into a head at the summit of the stem. They are found either
in the same heads as the pistillidia, or in distinct heads on the
same individuals (monoecious), or on separate individuals (dioe-
cious). The antheridlum (Fig. 1307) is merely a cylindrical
or club-shaped sac, composed of a single layer of cells, united
to form a delicate membrane ; within which are developed vasts
numbers of minute, very delicate cells, completely filling the sac.
The sac bursting at its apex when mature, the delicate vesicles
are discharged. Each of these contains a slender filament, thick-
ened at one end and tapering off to a fine point at the oilier: it may
be seen through the transparent walls, spirally coiled up in the interior
of each vesicle. When these vesicles are extruded in water under
the microscope, the contained filaments may be seen to execute lively
movements, wheeling round and round in the vesicle, or, when dis-
engaged from the latter, and assuming a corkscrew form, at the same
time advancing forward, the thin end of the filament almost always
preceding. Minute observation, which is very difficult, both from
the rapidity of the motion (which, however, is arrested by poisons)
and from the great delicacy of the whole structure, shows that the
movements arise from two long and extremely delicate cilia, attached
to the tapering end of the filament. These are the spermatozoids,
or true fertilizing organs. The pistillidia (Fig. 1306), which ap-
pear at the same time as the antheridia, and often mixed with them,
are flask-shaped bodies (like an ovary in shape), Avith a long neck
(resembling a style), composed of a cellular membrane. The neck
is perforated by an open canal, leading to a cavity below, at the base
of which a single cell is the germ of the future sporangium or spore-
case. Upon this the spermatozoids, or spiral filaments of the an-
theridia, act, one or more of them reaching it by finding their way
down the canal of the pistillidium. Then this cell commences a
special development, divides into two, and proceeds by ordinary cell-
multiplication to build up the sporangium or capsule, in which a
countless number of minute spores are produced. The spores of
Mosses are formed in the same way as pollen-grains, which they
much resemble in structure, being single cells with a double coat, of
2i)

338 REPRODUCTION IX

which the inner is the true cell-wall, and the outer a sort of secre-
tion from it. In germination, the inner or proper membrane of the
spore swells, and protrudes, from any part of its surface favorably
situated, a tubular process, which forms partitions as it elongates
and branches, giving rise to what has been fancifully named a pro-
embryo, or, better, a prothallus, — a rudimentary plantlet very unlike
a Moss, but closely resembling a branched Conferva, consisting, as
it does, merely of ramified threads, or rows of cells. After a time
certain cells of its various branches, taking a special development,
produce buds, which are soon covered with a tuft of rudimentary
leaves, and grow up into the leafy stems of the perfected plant. Here
a single spore — or rather a peculiar transitory plantlet developed
from it — gives rise at once to a number of individuals. And in
fecundation it is not the spores themselves that are fertilized, but
a cell which by its development gives origin to a spore-case, and this
to a vast number of spores.*

663. Fertilization of a Cell of a Prothallus, cr peculiar germinating
Plantlet, which thereupon develops into a Plant. This most extraordi-
nary mode of fecundation has recently been discovered in the Ferns
and other of the higher Cryptogamous orders. The fructification of
Ferns consists of spore-cases alone, which are borne on the back,
margins, or some other part of their leaves (Fig. 1287-1294), and
are filled with spores resembling those of Mosses. Since Mosses have
long been known to have organs answering in function to stamens,
as well as those answering to pistils, and since Fems are regarded
as plants of higher rank than Mosses, their antheridia were diligent-
ly sought for upon the fructifying plants, but in vain ; and botanists
were therefore forced to the unwilling conclusion, that the highest
organized of Cryptogamous plants were asexual. But antheridia,
essentially like those of Mosses, have been at length detected, not upon
the mature and fructifying plant, but upon the germinating plantlet.
The germination of the spores of Ferns had long since been ob-
served. The process begins in the same manner as in Mosses ; but
the extremity of the tubular prolongation of the spore, converted
by partitions into a row of cells, is developed into an expanded, leaf-
like body (the pro-embryo, or prothallus as it is now called), which

* The fullest aceount is by Hofmeister, Yeujhichende Untersuchungen der
" Keimung, E>i/fultung, und Frucldbilduny llo/terer Kryptogamen, etc. — Leipsic,
1851.

CRYPTOGAMOUS OR FLOWKRLKS3 PLANTS. 339

on a -small scale resembles a frondose Liverwort. Upon this body,
Niigeli, in 1844, found moving spiral filaments, like tho.-e of the an-
theridia of Mosses, &c. This, as Henfrey remarks, " seemed to
destroy all grounds for the assumption of distinct sexes, not only in
the Ferns, but in the other Cryptogamia; for it was argued that the
existence of these cellular organs producing moving spiral filaments
(the so-called spermatozoa) upon the germinating fronds, proved that
they were not to be regarded as in any way connected with the
reproductive processes. But an essay published by the Count
Suminski in 1848 totally changed the face of the question." On
the under side of the delicate, Marchantia-like, germinating frond,
Suminski found a number of cellular organs of two distinct kinds,
answering to antheridia and pistillidia. The former, which are the
more numerous, are cells elevated on the surface of the germinating
frond, in the cavity of which are formed other cells, filled with
minute vesicles containing each a spiral filament coiled up in its in-
terior. The organ bursts at its summit, and discharges the vesicles
in a mucilaginous mass ; the spiral filaments moving within the
vesicles at length make their way out of them and swim about in
the water. These filaments, or spermatozoids, resemble those of
Mosses, but are flat and ribbon-like, as in Chara, and possess accord-
ing to Suminski about six, according to Thuret numerous cilia, by
whose vibrations they are moved. The pistillidia, if they may be
so called, are rounded cavities in the cellular tissue of the same body,
opening on the under side, in the bottom of which is a single glob-
ular cell, from which the future growth proceeds. One or more of
the active spermatic filaments, liberated by the bursting of the an-
theridia, have been found to enter the open pistillidium, and to come
to rest and then wither away in contact with this specialized cell.
The latter now develops into a bud, or embryo, as it may perhaps
be termed, which grows in the ordinary way, producing an abbrevi-
ated axis, sending roots downward and leaf after leaf upwards ; and
so producing the mature Fern.* And, as most Ferns are perennial
plants, they produce year after year their fructification (consisting

* The English reader is referred to Henfrey's Translation of Mold's Anatomy
and Physiolotiy of die Vegetable CM: and Henfrey's llrport on die Reproduction
and supposed Existence of Sexual Organs in the higher Cryptoyainous Plants, in the
Report of the Biitish Association for the Advancement of Science, for 1851,
reprinted in Silliman's Journal, Vol. 14 and 15; from which the above account
has been condensed.

0 10 SPECIAL DIRECTIONS AND

merely of spores in spore-eases), without any known limit, and with-
out any other fecundation than that which occurred at first upon the
germinating plantlet.

6G4. In Ferns, accordingly, it is not the sporangium that is fer-
tilized, still less the spores, hut a cell of a peculiar transitory plant-
let formed by the germination of a spore. This cell otherwise will not
develop at all ; but when thus fecundated, it develops like a bud, and
grows into a plant of indefinite longevity, capable of fructifying by a
true parthenogenesis (571) throughout its long existence. This is
also known to be the case with Equisetaceae ; and the Lycopodia-
cea3 or Club-Mosses and other vascular Cryptogamous Plants are
thought to have analogous fecundation, although the details as yet
are not well made out.

CHAPTER XIII.

OF THE SPONTANEOUS MOVEMENTS AND VITALITY OF PLANTS.

Gfio. The facts brought to view in the preceding chapter, namely,
that either the spores or the fertilizing corpuscles or filaments of
most Cryptogamous plants of every order are temporarily endowed
with motivity, naturally raises the inquiry whether such phenomena
are altogether exceptional in the .vegetable kingdom, or whether the
power of executing movements is not a general endowment of plants
as well as of animals, although in lesser degree. As we pass in re-
view the various phenomena exhibited by plants in this respect, and
at the same time consider that self-caused motion, internal or exter-
nal, or the faculty of directing motion, is a necessary concomitant of
life, we shall probably arrive at the conclusion, that this surprising
activity of the microscopic spores and spermatozoids of Cryptogamous
plants is not altogether anomalous, — that these are merely more
vivid manifestations of a power which they share with ordinary vege-
tables,— that plants are endowed with life no less really than ani-
mals,— that the distinction between plants and the lower animals in
this respect is one of degree rather than of kind, — and that it is a
characteristic of living things to move.

SPONTANEOUS MOVEMENTS IN PLANTS. 341

66G. The Special Directions which the parts of all plants assume are
the result of self-caused movements, although such movements are
mostly much too slow to be directly observed. Among these the
most universal are the descent of the root in germination, the ascent
of the stem into the light and air, and the turning of branches and
the upper surface of leaves towards the light (120, 131, 204).
These directions evidently are not the result of mere growth. It is
not that the root grows downwards and the stem upwards ; but the
root end of the elongating radicle bends or curves in the course of
its growth so as to point downwards if not already in that position,
and the other extremity, with the plumule, curves upwards, and the
young stem, after reaching the light, if unequally illuminated, bends
towards the stronger light.

667. Strenuous attempts have been made to explain these changes
of direction upon mechanical principles. Mr. Knight thought that
the descent of the root and the ascent of the stem were caused by
gravitation ; and he seemed to show this by his celebrated experi-
ments of removing germinating seeds from the influence of gravita-
tion, and causing the root and stem to take a different direction in
obedience to a different force. lie fixed some beans ready to ger-
minate in a quantity of moss upon the circumference of a wheel, and
made it to revolve vertically at a rapid rate ; replacing the effect of
gravity by centrifugal force. On examination, after some days, the
young root was found to have turned towards the circumference, and
the stem towards the centre of the wheel. The same result took
place when the wheel was made to revolve horizontally with con-
siderable rapidity ; but when the velocity was moderate, the roots
were directed obliquely downwards and outwards, and the stems
obliquely upwards and inwards, in obedience both to the centrifugal
force and the power of gravitation, acting at right angles to each
other. It remained for Mr. Knight to explain how the same force,
gravitation, could produce such opposite effects, causing the stem to
ascend as well as the root to descend. This he ingeniously at-
tributed to their different mode of growth. The root growing at its
extremity only, he supposed that the soft substance of the growing
point would be acted upon by gravity like an imperfect solid, and
accumulated on the lower side ; while the stem, growing by the
elongation of an internode or a series of internodes already formed, its
solid tissues would be unaffected by gravity, which could affect only
its nutritive juices, causing their accumulation on the lower side of a
29*

342 SPFXIAL DIRECTIONS AND

stem out of the perpendicular line ; which side, thus more actively
nourished, would grow more vigorously than the upper, and so cau.-e
the stem to turn upwards. To show how baseless this ingenious
hypothesis is, we have only to remember, on the one hand, that the
fluid contents of the cells of plants arrange themselves in obedience
to other forces than gravity, and freely rise against its influence to
the summit of the loftiest trees, so that gravity could establish no
difference within the diameter of a germinating stem ; and on the
other, that the root in germination, if fixed upon its surface, will pen-
etrate a fluid of greater weight than itself, such as mercury. More-
over, Schultz and Mohl have shown that, by careful management in
reversing the ordinary conditions, — as by germinating seeds in
damp moss, so arranged that the only light they could receive was
reflected from a mirror, which threw the solar rays upon them directly
from below, — the ordinary direction of the organs could be reversed,
the roots turning upwards into the dark and damp moss, and the
stems downward into the light. This would prove that light has
more effect than gravitation, or any other imaginable influence of the
mass of the earth. Yet, — what shows that there is some real relation
between the direction assumed by the plant and the earth, — stems
which grow in complete darkness always point to the zenith, as is
seen in the shoots of vegetables in perfectly dark cellars, and in the
elongated, constantly upright stemlet of germinating seeds too deeply
buried to receive any light before they reach the surface of the soil.

GG8. The influence of a mass in some way analogous to attrac-
tion is also observed in the germination of the Mistletoe. Its form-
ing root turns regularly to the trunk or branch upon which it is.
parasitic, just as those of ordinary plants turn to the earth. And
that it is the mass and not the quality of the body which determines
the direction, is seen when germinating seeds of the Mistletoe are
fixed close to the surface of a cannon-ball : all the roots as they
grow point to its centre and advance to its surface, just as they do
to the branch of a tree which they penetrate.

6G9. When the stem has emerged from the earth into the light of
day, this exerts a controlling influence over its direction. Young
and green stems always tend to expose themselves as much as possi-
ble to the light, and bend, very promptly when delicate, towards the
most illuminated side, as is well observed when plants are raised in
an apartment lighted from a single aperture : and consequently in
the open air, being equally illuminated on all sides, they grow up-

SPONTANEOUS MOVEMENTS IN PLANTS. 343

right. De Candolle attempted a mechanical explanation of this
bending of green stems towards the light, connecting it with assimi-
lation and growth. He supposed that, as the side upon which the
light strikes will fix most carbon by the decomposition of carbonic
acid (34G-348), so its tissue will solidify faster, and therefore elon-
gate less, than the shaded side (which will become drawn, as the
gardener terms it) ; and the stem or branch will necessarily bend
towards the shorter or illuminated side. But when the light is
equally diffused around a plant, the decomposition of carbonic acid
will take place uniformly on all sides, and the perpendicular direc-
tion naturally be maintained. Two facts at once demolish this in-
genious theory. 1. It is now Avell known that, under the solar
spectrum, the decomposition of carbonic acid in the green parts of
plants is effected chiefly by the most luminous rays, that is, by yellow
light, and next to this by orange and red ; whereas the bending is
strongest under the violet and blue rays, the yellow producing little
curvature, and the red none at all. 2. When a stem curved under
the light is split from the apex downwards, so as to separate the.
illuminated from the shaded side, the former curves more than be-
fore, while the latter tends to straighten, — showing that it was
pulled over by the contraction of the concave side, and not pushed
over by its own greater growth. From all this it clearly appears
that the turning of parts towards the light, and the other special
directions of plants, are independent of growth, and apparently are
effected by some inherent power. At least, they have thus far
proved no more susceptible of mechanical explanation than the more
marked movements of animals.

670. In leaves it is the denser and deeper green upper surface
(262) that is presented to the light, while the paler lower surface, of
looser tissue, avoids it. The recovery of the natural position, when
the leaf is artificially reversed, is the more promptly effected in pro-
portion to the difference in structure and hue between the two strata.
This movement is so prompt in some plants, that their leaves follow
the daily course of the sun. The leaf is more capable of executing
such movements, on account of its extended surface, and its pliancy,
and also on account of its usual attachment by an articulation.
Here the slender vascular bundles oppose little resistance to lateral
motion, while the soft and usually cellular enlargement favors it.
Indeed, the efficient cause of the movement appears to be exerted
here, and to be connected with the unequal tension or turgescence of

344 SPECIAL DIRECTIONS AND

the cells on the two sides. We might therefore expect more prompt
and obvious changes of position in leaves than in stems. Familiar
examples of the kind are met with in the altered nocturnal position
of the leaves, &c. of many plants (often drooping, or folded as if in
repose), which Linnneus designated by the fanciful name of

G71. The Sleep of Plants. This is well seen in the foliage of the
Locust and of most Leguminous plants, and in those of Oxalis, or
Wood-Sorrel. It is most striking in the leaflets of compound leaves.
The nocturnal position is various in different species, but uniform in
the same .specie?, showing that the phenomenon is not mechanical.
Nor is it a passive state, for, instead of drooping, as do those of the
common Locust-tree, the leaflets are very commonly turned upwards,
as those of Honey-Locust, or upwards and forwards, as in the Sensi-
tive-Plant, contrary to the position into which they would fall from
their own weight. De Candolle found that most plants could be
made to acknowledge an artificial day and night, by keeping them in
darkness during the day, and by illuminating artificially at night.
The sensibility to light appears to reside in the petiole, and not in
the blade of the leaf or leaflet ; for these movements . are similarly
executed, when nearly the whole surface of the latter is cut away.

G72. The leaves of the blossom also assume various positions,
according to the intensity and duration of the light. Many expand
their blossoms in the morning and close them towards evening,
never to be opened again, as thoe of Cistus, Portulaca, and Spider-
wort ; while others, like the Crocus, close when the sun is with-
drawn, but expand again the following morning. On the other hand,
the Evening Primrose, Silene noctiflora, &c. unfold their petals at
twilight, and clore at sunrise. The "White Water-Lily (Nymphasa)
expands in the full light of day, but uniformly closes near the mid-
dle of the afternoon, and is then usually withdrawn beneath the sur-
face of the water. The Morning-Glory opens at the dawn ; the
Lettuce, and most Cichoraceous plants, a few hours later, but close
under the noonday sun ; the Mirabilis is called Four-o'clock, because
opening nearly at that hour in the afternoon, and it closes the next
morning ; and so of other species, — each having its own hour or
amount of light in which its blossoms open or close. Berthelot men-
tions an Acacia at Teneriffe, whose leaflets regularly close at sunset
and unfold at sunrise, while its flowers close at sunrise and unfold
at sunset. Although these movements, both in leaves and blossoms,
are undoubtedly dependent on the light, they arc by no means directly

SPONTANEOUS MOVEMENTS IN PLANTS. 345

governed by it. The so-called sleep of (lie common Sensitive Plant,
lor instance, begins just before sunset, but its waking frequently pre-
cedes the dawn of day ; showing that it is not the mere amount of
the light which governs the position, in the manner of a mechanical
power.*

673. Sensible Movements from Irritation. All the changes of posi-
tion already described — like those of the hands of a clock or of
the shadow on a dial — are too slow for the motion to be directly
seen. But a greater exaltation apparently of this common faculty
is observed in the leaflets of various Leguminous plants, especially
of the Mimosa tribe, which, when roughly touched, assume their
peculiar nocturnal position, or one like it, by a visible and sometimes
a rapid movement. The Sensitive Plant of the gardens (Mimosa
pudica) is a familiar instance of the kind, suddenly changing the
position of its leaflets on being touched or jarred, and applying
them one over the other close upon the secondary petiole ; if more
strongly irritated, the secondary petioles alfo bend forward and
approach each other, and the general petiole itself sinks by a bend-
ing at the articulation with the stem. Similar although less vivid
irritability is shown by the Mimosa strigilloia and the Schrankia of
the Southern States, where the leaflets promptly fold up when
brushed with the hand. The most remarkable instance of the kind,
however, is presented by another native plant of the United States,
the Dionsea muscipula, or Venus's Fly-trap (Fig. 297, 298) ; in which
the touch even of an insect, alighting upon the upper surface of the
outspread lamina, causes its sides to close suddenly, the strong
bristles of the marginal fringe crossing each other like the teeth of
a steel-trap, and the two surfaces pressing together with considerable
force, so as to retain, if not to destroy, the intruder, whose struggles
only increase the pressure which this animated trap exerts. This
most extraordinary plant abounds in the damp, sandy savannas in
the neighborhood of Cape Fear River, from Wilmington to Fayette-

* The odors of flowers, also, arc sometimes given off continually, as in the
Orange and the Violet, or flowers may nearly lose their fragrance during the heat
of mid-day, as in most cases ; while others, such as Pelargonium triste, Hesperis
tristis, and most dingy flowers, which are almost scentless during the day, ex-
hale a powerful fragrance at night. The night-flowering Ccreus grandiflorus
emits its powerful fragrance at intervals ; sudden emanations of odor being
given ofF about every quarter of an hour, during the brief period of the expan-
sion of the flower.

346 SPONTAXKOUS MOVEMENTS IN PLANTS.

ville, North Carolina, where it is exceedingly abundant ; but it is
not elsewhere found.

674. A familiar, although less striking, instance of the same kind
is seen in the stamens of the common Barberry, which are so excit-
able, that the filament approaches the pistil with a sudden jerk, when
touched with a point, or brushed by an insect, near the base on the
inner side. The object of this motion seems plainly to be the dis-
lodgement of the pollen from the cells of the anther, and its projec-
tion upon the stigma. But in the D'.onrca it is difficult to conceive
what end is subserved by the capture of insects. In a species of
Stylidium of New Holland, not uncommon in conservatories, the
column, consisting of the united stamens and styles, is bent over to
one side of the corolla ; but if slightly irritated, it instantly springs
over to the opposite side of the flower. These are among the more
remarkable cases of the kind, but by no means the only ones.
Anatomical investigation brings to view no peculiarity in the struc-
ture of such plants which might explain these movements. Some
other movements, which have been likened to these, are entirely
mechanical ; as that of the stamens of Kalmia, where the ten an-
thers are in the bud received into as many pouches of the mono-
petalous corolla, and are carried outwards and downwards when the
corolla expands. In this way the slender filaments are strongly re-
curved, like so many springs ; until at length, when the anthers are
liberated by the full expansion of the corolla, or by the touch of a
large insect or other extraneous body, they fly upwards elastically,
projecting a mass of pollen in the direction of the stigma.

675. The twining of stems round a support, and the coiling of
tendrils, are attributed by Mohl to a dull irritability ; and this is the
most plausible explanation that has been offered. The inner side,
which becomes concave and has smaller cells, is in this, as in other
cases, the irritable portion. When a foreign body is reached, a
contraction of this side causes the tendril partially to embrace the
support : this brings the portion just above into contact with it,
which is in like manner incited to curve ; and so the hold is secured,
or the twining stem continues to wind around the support. In ten-
drils this irritability, propagated downward along the concave side,
would appear to cause its contraction, which throws the whole into
a spiral coil, or, when fixed at both ends, into two opposite spiral
coils, thus approximating the growing stem to the supporting
body.

SPONTANEOUS MOVEMENTS IN PLANTS. 347

676. In all these cases, whether of slow or rapid change of posi-
tion, the immediate cause of the movement, however incited, must
be either the shortening of the cells on the concave side, or their
elongation on the convex side. The fact that stems curved towards
the light tend to curve still more when the convex side is cut
away (G69) points to a contraction of the cells on the concave side
as the cause of the curvature. The elastically bursting pods of the
Balsam or Touch-me-not (Impatiens), &c. confirm this view. Here
the valves of the capsule curve inwards very strongly when liber-
ated in dehiscence ; and that this is owing to the shortening of the
cells of the inner layer, and not to the enlargement or turgescence of
those of the thick outer layer, is readily shown by gently paring
away the whole outer portion before dehiscence ; for the inner layer
when liberated still incurves and rolls itself up as strongly as before.
The short valves at the summit of the pod of Kchinocystis slowly
curve outwards in dehiscence ; here the cells of the outer layer of
the valve are longer and narrower than those of the inner, and
the latter are stretched and torn in opening ; so that here the con-
traction of the cells on the side which becomes concave is undoubt-
edly the cause of the movement. And since muscular movements
are effected by the contraction of the cells which, placed end to end,
compose a muscular fibril, we may suspect that vital movements
generally, both in vegetables and in animals, are so far analogous,
that they are brought about in the same general way, viz. by the
shortening of cells. Even the opening and closing of the stomata
of the leaves (268) appear to be controlled by the vital force, and
to be effected by a self-caused change in the form of the guardian
cells. How the light, or external irritation, or any other influence,
acts in inciting this change of form of the cells of some part of a
plant, we know no more, and no less, than we know how a nerve, or
an electrical current, acts upon a muscle of an animal to bring
about the contraction or change of shape of its component cells.
If animals make

677. Spontaneous or Automatic Movements, so also do some plants

execute brisk and repeated movements irrespective of extraneous
force, or even of extraneous excitation, and which, indeed, are ar-
rested by the touch. An instance of such spontaneous and contin-
ued motion, of the most remarkable kind, is furnished by the trifoli-
olate leaves of Desmodium gyrans, an East-Indian Leguminous plant.
The terminal leaflet does not move, except to change from the

348

SPONTANEOUS MOVEMENTS IN TLANTS.

diurnal to the nocturnal position, and the contrary ; but the lateral
ones are continually rising and falling, both day and night, by a suc-
cession of little jerks, like the second-hand of a time-keeper , the
one rising while the other falls. Exposure to cold, or cold water
poured upon the plant, stops the motion, which is immediately re-
newed by warmth. The late Dr. Baldwin is said by Nut-all to
have witnessed the same thing in our own Desmodium cuspidatum,
in Georgia ; but the observation has never been confirmed. In
several tropical Orchideous plants, and especially in a species of
Megaclinium, the lower petal, or labellum, executes similar spontane-
ous movements, with great freedom and pertinacity. Such phenom-
ena, occurring as they do in Pha?nogamous plants of ordinary struc-
ture may serve to render more credible the true vegetable character
of the

G78. Free Movements of llic

Spores of AlgCC, and the cor-
puscles or spiral filaments of
the antheridia of most Cryp-
togamous plants, already re-
ferred to (G59 - 6G3). The
spores of most of the lower
Algaa are now known to ex-
hibit this peculiar activity
at the time of their discharge
from the parent cell, when,
for rorae moments, or usual-
ly for several hours, they
behave like infusory ani-
mals, executing spontaneous
mo'.'ements in the water,
until they are about to ger-
minate. This singular move-
ment was first detected many
years ago in Vaucheria G39 MJ 6;i e" w

FIG. C36. 1'ruiting end of a plant of Vaucheria geminata (after Thuret); one cf the
branches still containing its spore 637 Moving spoie just escaped from the apex of the
other branch ; the ciliary apparatus seen over the whole surface C38. Spore in germination.

FIG 639-642. Successive steps in the germination of (Edogouium (Conferva) vesicata.
643 The plant developed into a series of cells, four of which display the successive steps in tho
formation of a spore. 644 The locomotive spore with its vibratile cilia (copied from Thuret).
When tho movement ceases, and it begins to gcrmiuate, it appears as in 639 (The antheridia
or fertilizing apparatus of these plants were not Unowu when these figures were made.)

SPONTANEOUS MOVEMENTS IN PLANTS. 349

(Fig. 89, G36). Immediately on its discharge from the mother
plant the spore begins to move freely in the water, and continues to
do so for some hours, when it fixe3 itself and begins to grow (Fig.
638). Its movements, moreover, like those of the antheridial fila-
ments or corpuscles, may be enfeebled or arrested by the application
of a weak solution of opium or chloroform. Through these means
it has been ascertained that they are caused by the vibrations of
minute cilia which cover the surface, which are rendered visible
by thus enfeebling their movement, and which exhibit the closest
resemblance to the vibratile cilia of animals, especially those of the
polygastric animalcules. In the Conferva tribe generally the vibra-
tile cilia occupy one end of the spore, and are in some cases numer-
ous (as in Fig. G44), in others only two or three in number. The
spores are small, and of about the same specific gravity as the water
in which they live, so that a slight force suffices to propel them.

G79. Locomotion of Adult Microscopic Plants. The spores of Vau-

cheria and the like, becoming quiescent before germination, grow
into fixed thread-like plants of considerable size, endowed with no
greater degree of motivity than ordinary vegetables. A multitude
of still simpler Alga;, however, swarm in every pool or stream, so
minute in size as to be individually totally invisible to the naked
eye (most of them when full grown are very much smaller than the
spores of Yaucheria, &e.) ; and these are endowed, even at maturity,
with such powers of locomotion that their vegetable character,
•although now well made out, was long in question on this account
alone. Of this kind are the various species of Oscillaria (Fig. S4),
so named from the writhing movement they exhibit, the Desmidi-
acea), to which Closterium (Fig. 631) belongs, and the nearly
allied Diatomaeerc, — the lowest, minutest, and the most freely
moving of plants, but clearly members of the vegetable kingdom
notwithstanding. These execute free movements of translation, in
some cases slow, in others rapid ; but the mechanism of the motion
is still unknown.

680. Not only, therefore, do plants generally manifest impressi-
bility or sensitiveness to external agents, and execute more or less
decided, though slow, movements ; but many species of the higher
grades exhibit certain vivid motions, either spontaneous or in conse-
quence of extraneous irritation ; Avliile the lowest tribes of aquatic
plants, as they diminish in size and in complexity of organization,
habitually execute, at some period at least, varied spontaneous move-
30

3o0 SPONTANEOUS MOVEMENTS IX PLANTS.

merits, -which we are unable to distinguish in character from those of
the lowest animals. It is at their lowest confines, accordingly, that
the vegetable and the animal kingdoms approach or meet, and even
seem to blend their characters.

G81. When we consider that the excitability of sensitive plants
is often transmitted, as if by a sort of sympathy, from one part to
another >, that it is soon exhausted by repeated excitation (as is
certainly the case in Dionrea, the Sensitive-Plant, &c), to be re-
newed only after a period of repose ; that all plants require a
sea-on of repose ; that they consume their products and evolve heat
under special circumstances with the same results as in the animal
kingdom (Chap. VII.) ; that, as if by a kind of instinct, the various
organs of the vegetable assume the positions or the directions most
favorable to the proper exercise of their functions and the supply of
their wants, to this end surmounting intervening obstacles ; when
we consider in this connection the still more striking cases of spon-
taneous motion that the lower Alga} exhibit ; and that all these
motions are arrested by narcotics, or other poisons, — the narcotic
and acrid poisons even producing effects upon vegetables respectively
analogous to their different effects upon the animal economy ; we
cannot avoid attributing to plants a vitality and a power of " making
movements tending to a determinate end," not different in nature,
perhaps, from those of the lowest animals. Probably life is essen-
tially the same in the two kingdoms ; and to vegetable life faculties
are superadded in the lower animals, some of which are here and
there not indistinctly foreshadowed in plants.

G82. The essential differences between plants and animals were
enumerated at the commencement of this work (1G), and have been
illustrated in its progress. Distinct as are the general structure
and the oifiees of the two great kinds of organized beings, it is still
doubtful whether the discrimination is absolute, or whether the
functions of the vegetable and the animal may not, in some micro-
scopic organisms, be imposed upon the same individual.

PAUT II.

SYSTEMATIC BOTANY.

683. In the preceding chapters plants have been considered in
view of their structure and action. And when different plants have
been referred to and their diversities noticed, it lias been in eluci-
dation of their morphology, — of the exuberantly varied forms or
modifications under which the simple common plan of vegetation is
worked out, as it were, in rich detail. The vegetable kingdom, that
is, vegetation taken as a great whole, presents to our view an im-
mense number of different kinds of plants, more or less resembling
each other, more or less nearly related to each other. It is the
object of Systematic Botany to treat of plants as members of a
system, or orderly parts of a whole, — and therefore to consider
them as to their kinds, marked by differences and resemblances, and
to contemplate the relations which the kinds, or individual members
of the great whole, sustain to each other. To this end the botanist
classifies them, so as to exhibit their relationships, or degrees of
resemblance, and expresses these in a systematic arrangement or
classification, — designates them by appropriate appellations, and
distinguishes them by clear and precise descriptions in scientific lan-
guage ; so that not only may the name and place in the system, the
known properties, and the whole history of any given plant, be read-
ily and surely obtained by the learner, but likewise an interesting
view may be obtained of the general scheme or plan of the Cre-
ator in the Vegetable World.

684. Our present endeavor will be to explain the general prin-
ciples of natural-history classification, and the foundation, or facts
in nature, upon which it rests, and then cursorily to show how these
are applied to the actual arrangement of the known species of
plants.

352 PRINCIPLES OK CLASSIFICATION.

CHAPTER I.

OF THE PRINCIPLES OF CLASSIFICATION.

68.). Plants and animals — the members of the organic king-
doms of nature — exist as individuals (13), of definite kinds, each
endowed with the characteristic power of producing like individuals
and so of continuing (he succession. The different sorts (1.) are re-
produced true to their essential characteristics from generation to
generation ; and (2.) they exhibit unequal and very various degrees
of resemblance or of dissimilarity among themselves. These simple
propositions lie at the foundation of all classification and system in
natural history. Upon the first rests the idea of species ; upon the
second that of genera, orders, and all groups higher than species.

G86. Individuals. The idea of individuality is derived from man
and ordinary animals, and thence naturally extended to vegetables.
Individuals are being-;, owing their existence and their characteris-
tics to similar antecedent beings, and composed of parts which
together constitute an independent whole, indivisible except by mu-
tilation. Individuality is perfectly exemplified in all the higher and
most of the lower animals, which multiply by sexual propagation
only, and in which the offspring, or the ovum, early separates from
the. parent ; but it is incompletely realized in those animals of the
lower grade which are propagated by buds or offshoots as well as
b)- ova, and where the. off-pring may remain more or less intimately
connected with the parent. Still more is this so in plants, which
in every grade are or may be propagated by buds or offshoots ;
which in vegetation develop an indefinite number of similar parts ;
which produce branches like the parent plant, and capable either of
continuing to grow in connection with it, or of becoming independent
(232). The individual plant, therefore, is evidently not a simple
and true individual in the proper sense of the word, — in the sense
that an ordinary animal is. A kind of social or corporate individu-
ality in the complex radiated animals often gives a certain limita-
tion and shape to the congeries or pohjpidom, and in many of them
even subordinates certain parts to the common whole, assigning to
them special functions for the common weal : and this is universally
and more strikingly the case with plants, except the very simplest.

INDIVIDUALS. 353

So that for practical purposes, and in a loose, general sense, Ave
take the. -whole plant as an individual, so long as it forms one con-
nected mass, and no longer. But in a philosophical view we cannot
well regard this congeries as the true vegetable individual.

687. Accordingly many botanists (of whom are Thouars at the
beginning of the present century, and Braun * at the present day)
regard as the true individual the shoot, or simple axis with its foli-
age, &c, Avhether this he the primary stem with its roots implanted
in the soil, or a branch implanted on the stem. This view simpli-
fies our conception of a vegetable, but is itself open to all the olyec-
tions it raises against the individuality of the plant as a whole. For
just as the herh, shrub, or tree is divisible into shoots or series of
similar axes, so the shoot is divisible into similar component parts,
or phytons (1G3), indefinitely repeated, and which may equally give
rise to independent plants. Those philosophical naturalists, there-
fore, who find no stahle ground in this position, are forced towards
one of two opposite extremes. Some, justly viewing sexual repro-
duction as of the highest import, are led to regard the whole vege-
tative product of a feed as theoretically constituting one individual,
whether the successive growths remain united, or whether they form
a thousand or a million of vegetables, as may often happen. Ac-
cording to this view, all the Weeping- Willow trees of this country
are parts of one individual ; and most of our Potato plants must be-
long to one multitudinous individual, while other.3 wholly similar, but
freshly grown from seed, arc each individuals of themselves ; — a
view which apparently amounts to an absurdity in terms and in fact.
Others, following out the idea mentioned above, and laying the main
stress upon simplicity and indivisibility, rather than upon tendency
to separation, regard the phyton in ordinary plants, and the cell in
those of lowest grade, as on the whole best answering, in the vege-
table kingdom, to the simple individual in the animal. But this is
merely a question of greater or less analogy. For the individual, in
the proper sense of the term, is more or less confluent into a vegeta-
tive cycle in all plants, and in many of the lower animals, and a'tains
full realization only in the higher grades of organized existence.

* Sec his elaborate treatise, On the. Vegetable Individual in its Relation to Species
(of which a translation from the German, by C F. Stone, was published in the
American Journal of Science and the Arts, vols 19 and 20, 1S55), for the com-
pletcst development of this view, and for the history of tlio subject generally.
30*

354 PRINCIPLES OF CLASSIFICATION.

688. But, whatever it may be which we practically or philosophi-
cally regard as the vegetable individual, it is evident that plants as
well as animals occur in a continued succession of organisms or
beings which stand in the relation of parent and offspring. Each
particular sort is a chain, of which the individuals are the links.
To this chain, or (as expressed by Linnams) this perennial succes-
sion of individuals, the natural-historian applies the name of

C89. Species (14). Every one knows that the several sorts of
plants and animals steadily reproduce themselves, or, in other words,
keep up a succession of essentially similar individuals, and under
favorable circumstances increase their numbers. Each particular
kind of cultivated plant or domesticated animal is represented before
our eyes in a mass of individuals, which we know from observation
to a certain extent, and from necessary inference, have sprung
from the same stock. And common observation has led people
everywhere to expect that the different sorts will continue true to
their kind, or at least to conclude that the different sorts of plants
or of animals do not shade off one into another by insensible grada-
tions, like the colors of the rainbow, as would have been the case if
there were not distinct kinds at the beginning, and if their distinc-
tions were not kept up, unmingled, and transmitted essentially un-
altered, from generation to generation. So wc naturally assume that
the Creator established a definite, although a vast, number of types
or sorts of plants and animals, and endowed them with the faculty
of propagation each after its kind ; and that these have so continued
unchanged in all their essential characteristics. Out of these gen-
eral observations and conceptions the idea of species must have origi-
nated ; from them we deduce its scientific definition. Namely, that
the species is, abstractly, the type or original of each sort of plant,
or animal, thus represented in time by a perennial succession of like
individuals, or, concretely, that it is the sum of such series or con-
geries of individuals ; and that all the descendants of the same stock,
and of no other, compo-e one species. And, conversely, as we can
never trace back the genealogy far, we naturally infer community
of origin from fraternal resemblance ; that is, we refer to the same
species those individuals which are as much alike as those are
which we know to have sprung from the same stock.*

* Wc use the word stock advisedly, (and in one of its proper meanings, that
of the original or originals of a lineage,) to avoid the assertion or denial of the

SPECIKS AND VARIETIES. 355

GOO. Specific identity is not of course inferred from every strongly
marked resemblance ; for the resemblance may be only that of genus,
and individuals so related are inferred not to have had a common
origin. Nor is it denied on account of every difference ; for individu-
als of the same stock may differ considerably ; in fact, no two plants
are exactly alike, any more than two men are. Such differences
when they become distinctly marked give rise to

G91. Varieties. If two seeds from the same pod are sown in dif-
ferent soils, and submitted to different conditions as respects heat,
light, and moisture, the plants that spring from them will show
marks of this different treatment in their appearance. Such differ-
ences are continually arising in the natural course of things, and to
produce and increase them artificially is one of the objects of culti-
vation. Such variations in nature are transient ; the plant often
outlasting the cause or outgrowing its influence, or else perishing
from the continued and graver operation of the modifying influ-
ences. But in the more marked varieties which alone deserve
the name, the cause of the deviation is occult and constitutional ; the
deviation occurs we know not why, and continues throughout the
existence and growth of the herb, shrub, or tree, and consequently
through all that proceeds from it by propagation from buds, as by off-
sets, layers, cuttings, grafts, &c. In this way choice varieties of Ap-
ples, Pears, Potatoes, and the like, are multiplied and perpetuated.

G92. Since the progeny inherits or tends to inherit all the char-
acters and properties of the parent, constitutional varieties must have
a tendency to be reproduced by seed, — a tendency which might
often prevail, within certain limits, over that general influence which
would rem nd the variety to the normal state, Avere it not for the
commingling which so commonly occurs in nature, through the cas-
ual fertilization of the ovules of one individual by the pollen of other
individuals of the same species. By assiduously pursuing the oppo-

origin of each species from a single individual or a single pair, — a question
which science docs not furnish grounds for deciding. It is evidently more
simple to assume the single origin, where there is no presumption to the con-
trary, as there may be in the case of tricecious or of organically associated plants
or animals ; but the contrary supposition docs not affect our idea of species, if
we suppose the originals to have been as much alike as individuals proceeding
from the same parent arc, and to have had a common birthplace. The investi-
gation of the geographical distribution of plants more and more favors the idea
of the dissemination of each species from a ccutrc of its own.

3.56 PRINCIPLES OF CLASSIFICATION.

site course in domesticated plants, that is, by constantly insuring the
fertilization of the ovules of a marked variety by the pollen of the
same, and by saving seed only from such of the resulting progeny as
possess the desired peculiarity in the highest degree, and so on for
several generations, it would appear that

G93. Races, viz. varieties whose characteristics are transmissible
by seed with considerable certainty, may generally be produced. Of
this kind are the particular sorts of Indian Corn, Rye, Cabbage,
Lettuce, Radishes, &c, and indeed of nearly all our varieties of culti-
vated annual and biennial esculent plants, as Avell as of several per-
ennials, many of which have been fixed through centuries of domes-
tication. What is now taking place with the Peach in this country
may convince us that races may be developed in trees as well as in
herbs, and in the same manner ; and that the reason why most of
our cultivated races are annuals or biennials is because these can
be perpetuated in no other way, and because the desired result
is obtainable in fewer years than in shrubs or trees. Although
races hardly exist independently of man, he cannot be said to origi-
nate their peculiarities, nor is it known how they originate. The
sports, as the gardener calls them, appear as it were accidentally
in cultivated plants. The cultivator merely selects the most promis-
ing sorts for preservation, leaving the others to their fate. By par-
ticular care he develops the characteristic feature, and strengthens
and fixes, in the manner already explained, the tendency to become
hereditary, so securing the transmissibility of the variety as long as
he takes sufficient care of it. If not duly cared for, they dwindle and
lose their peculiarities, or else perish ; if allowed to mix with normal
forms, they revert to the common state of the species. Were culti-
vation to cease, all these valued products of man's care and skill
Avould doubtless speedily disappear ; the greater part, perhaps, would
perish outright ; the remainder would revert, in a few generations
of spontaneous growth, to the character of the primitive stock.

G94. Although man has no power to create the peculiarities of
such varieties, he may manage ?o as not only largely to increase
them, but also to combine the peculiarities of widely different varie-
ties of a species, and thereby produce novel results. This is effected
by Cross-breeding, i. e. by fertilizing the pistil of one variety with the
pollen of another variety of the same species. In this way most
esteemed new varieties of flowers and fruits are originated, which
combine the separate excellences of both parents. The cultivator

RACKS, HYBRIDS, KTC. 357

often proceeds one step farther, in certain cases, and gives rise to a
different kind of cross-breeds, viz.

695. Hybrids. These are cross-breeds from different hut nearly
related species. It is well known that, by proper precautions, the
pistil of a flower of one species may often he fertilized by the pollen
of another of a similar constitution, and that the plants raised from
the seeds so produced combine the characters and properties of
both parents. Some kinds, such as Azaleas and Pelargoniums, hy-
bridize very readily ; in others hybridism is effected with difficulty
between nearly related species. The gardener produces hybrids
among most of his favorite plants, and variously cross-breeds and
mingles them, so as to confuse the limits of many cultivated species.
But in nature hybrids rarely occur. Not more than fifty wild kinds
are clearly known as of continued or frequent occurrence. Others
may perhaps be originated from time to time ; but their existence
is transient. For hybrids are generally, if not always, sterile, and
therefore incapable of perpetuation by seed. But their ovules may
be fertilized by the pollen of either of their parents, when the
progeny reverts to that species, probably retaining, however, some
traces of the mixture, unless this should be obliterated by successive
fertilizations from individuals of the same parent species. It is
probable that cross-fertilization between different individuals of the
same species is more common than is generally supposed, and that
it is one of Nature's means for repressing variation. On the other
hand, continued self-fertilization (or breeding in and in) is almost
sure to perpetuate, as well as farther to develop, individual peculiari-
ties, i. e. those of variety or race.

696. However plants may be modified by art and man's device,
the systematic botanist proceeds upon the ground that the distinc-
tions between species, Avhether small or great, are real, and in nature
are permanent, — that variation, wide as it may be, is naturally re-
stricted within certain limits. And this appears to be true. As dis-
tinctions subordinate to species are in nature both indefinite and
transitory, these, however important to the cultivator, are of little
account with the systematic botanist.

697. Species are the true subjects of classification. And the end
and aim of systematic botany is to ascertain and to express their
relationship to each other. The whole ground in nature for the
classification of species is the obvious fact that species resemble
or differ from each other unequally and in extremely various de-

3.")8 PRINCIPLKS OF CLASSIFICATION.

grees. If this were not so, or if related species differed one from
another by a constant quantity, so that, when arranged according
to their resemblances, the first differed from the second about as
much as the second from the third, and the third from the fourth,
and so on throughout, — then, with all the diversity in the vege-
table kingdom there actually is, there could be no natural founda-
tion for their classification. The multitude of species would render
it necessary to classify them, but the classification would be wholly
artificial and arbitrary. The actual constitution of the vegetable
kingdom, however, as appears from observation, is, that some species
resemble each other very closely indeed, others differ as widely as
possible, and between these the most numerous and the most various
grades of resemblance or difference are presented, but always with
a manifest tendency to compose groups or associations of resembling
species, — groups the more numerous and apparently the less defi-
nite in proportion to the number and the nearness of the points of
resemblance. These various associations the naturalist endeavors to
express, as far as is necessary or practicable, by a series of generali-
zations,— of which the lower or particular are included in the
higher, — based on the more striking, or what he deems the most
important (i. e. the most definite or least exceptional) points of re-
semblance of several grades. Linnaeus and the naturalists of his
day mainly recognized three grades of association, or groups supe-
rior to species, viz. the genus, the order, and the class ; and these are
still the principal members of classification. Of these

G98. Genera (plural of Genus) ai-e the more particular or special
groups of related species. They are groups of species which are
most alike in all or most l-espeets, — which are constructed, so to
say, upon the same particular model, with only circumstantial dif-
ferences in the details. They are not necessarily nor generally the
lowest definable groups of species, but are the lowest most clearly
definable groups which the botanist recognizes and accounts worthy
to bear the generic name ; for the name of the genus with that of
the species added to it is the scientific appellation of the plant or
animal. Constituted as the vegetable and animal kingdoms are, the
recognition of genera, or groups of kindred species, is as natural an
operation of the mind as is the conception of species from the asso-
ciation of like individuals. This is because many genera are so
strongly marked, or at least appear to be so, as far as ordinary ob-
servation extends. Every one knows the llo e genus, composed of

GENERA AND ORDERS. 359

the various species of Roses and Sweetbriers ; the Bramble genus,
comprising Raspberries, &c, is popularly distinguished to a cer-
tain extent ; the Oak genus is distinguished from the Chestnut and
the Beech genus, &c. : each is a group of species whose mutual
resemblance is greater than that of any one of them to any other
plant. The number of species in such a group is immaterial, and
in fact is very diverse. A genus may be represented by a single
known species, when its peculiarities are equivalent in degree to
those which characterize other genera, — a case which often occurs ;
although if this were generally so, genus and species Avould be
equivalent terms. If oidy one species of Oak were known, the Oak
genus would have been as explicitly discerned as it is now that the
species amount to two hundred ; it would have been equally distin-
guished by its acorn and cup from the Chestnut, Beech, Hazel, &c.
Familiar illustrations of genera in the animal kingdom are furnished
by the Cat kind, to which belong the domestic Cat, the Catamount,
the Panther, the Lion, the Tiger, the Leopard, &c. ; and by the
Dog kind, which includes with the Dog the different species of
Foxes and Wolves, the Jackal, &c. The languages of the most
barbarous people show that they have recognized such groups.
Naturalists merely give to them a greater degree of precision, and
indicate what the points of agreement are.

699. If all' such groups were as definite and as conspicuously
marked out as those from which illustrations are generally taken,
genera might be as natural as species. But unfortunately the pure-
ly popular genera are comparatively few, and although often cor-
rectly founded by the unscientific, jret they are as frequently wrongly
limited, or based upon fanciful resemblances. Popular nomencla-
ture, embodying the common ideas of people, merely shows that
generic groups are recognizable in a considerable number of cases,
but not that the whole vegetable or the whole animal kingdom is
divisible into a definite number of such groups of equally or some-
what equally related species. "Whether this proves to be so or not,
and Avhether genera are actually limited groups throughout, this is
not the place to consider. Suffice it to say, that there is a ground
in nature for genera, and that the naturalist is obliged to treat them,
for systematic purposes, as strictly definite groups of species. "While
ge/uera represent the closer relationships of species,

700. Orders or Families .(as they are interchangeably called in
botany) express remoter relationships or more general resemblances.

360 PRINCIPLES OF CLASSIFICATION.

They are groups of kindred genera, or rather genera of a higher
grade. For example, Oaks, Chestnuts, Beeches, Hazels, and Horn-
beams constitute so many genera, which, although quite distinct, have
so strong a family likeness, and are so much alike in their general
structure and properties, that they are associated into one order or
family group (the Oak family) ; while the Birches and the Alders
form another order not very different in character, and the Walnuts
and Hickories another. So the Pines, Firs or Spruces, Larches,
Cedars, &c, obviously related among themselves to much more than
they are to any other genera, are members of the Pine family ; the
Raspberry, Blackberry, and Strawberry, with many others, are as-
sociated with the Rose in the Rose family ; and so on.

701. Classes are to orders what these are to genera. They ex-
press more extensive, or the most extensive relations of species, each
class embracing all those species which are framed upon the same
general plan of structure, however differently that plan may be
carried out in particulars.' Thus all Exogenous or Dicotyledonous
plants constitute one class, their stems, their embryo, their leaves,
&c. being constructed upon the same general plan in all the species,
while Endogenous or Moncotyledonous plants for the same reasons
compose another class.

702. The sequence of groups, rising from particular to universal,
is Species, Genus, Order, Class ; or, in descending from the univer-
sal to the particular,

Class,

Okdkr,

Genus,

Sl'ECILS.

703. These are the common framework of all method; of classifi-
cation, both in the animal and the vegetable kingdoms. But these
do not exhaust our powers of analysis, nor express all the gradations
which we may observe in the relationship of species. They merely
gather up what are deemed the most essential indications of re-
lationship, and express them under three grades superior to species,
which always carry with them distinctive names. But a more elab-
orate analysis is often requisite, on account of the large number
of objects to be arranged, and the various degrees of relationship
which may come into view. And these, when needful, are expressed
in a series of intermediate groups or divisions, which may or may
not require distiucihe names. Names for them are, however, a

ORDERS, CLASSICS, AND THEIR SUBDIVISION'S. 3G1

great convenience, especially for those which are most natural and
definite. For some of these intermediate groups may he as dis-
tinctly marked as are those which we call genera or orders.

704. The great advantages and proper use of this intermediate
grouping are, that it secures all the benefits of complete analysis
without undue multiplication of genera and orders, and that, hy ex-
tending the scale, more grades of relationship may be noted, and the
whole expressed in our systems in truer perspective. Accordingly,
when groups of species below what we take for genera are recog-
nized, and found to be so well marked that by a little lowering of
the scale they would be received as genera, they are denominated
Subgenera. If less definite, we term them merely Sections. For
example, Pyrus, the Pear genus, embraces Apples, Pears, Crab-
apples and the like ; and the Pear itself is the type or normal rep-
resentative. From this the Apple and the several species of Crab-
apple differ considerably, but not quite enough to warrant generic
separation: they are therefore recognized as forming a subgenus,
Mains, of the genus Pyrus. Again, the Bramble genus, Rubus, com-
prises both Raspberries and Blackberries, which, although distin-
guished by everybody, are not so much or so definitely different from
each other as Apples and Crab-apples are from Pears ; so they are
ranked merely as sections of the Bramble genus. If we were to
receive all such particular groups of species as genera, and give them
substantive names, as many naturalists are doing, the nicer grada-
tions of affinity would be disregarded, while genera would be reck-
oned by tens of thousands ; at length half our species would become
genera with substantive names, and the whole advantage of classifi-
cation and nomenclature would be lost. The proper discrimination
of genera is the real test of a naturalist.

705. When groups intermediate between genera and orders are
admitted, they are generally denominated Tribes, and their divis-
ions, if any, Subtribes. But the highest divisions of orders, when
marked by characters of such importance that it might fairly be
questioned whether they ought not to be received as independent
orders, take the name of Suborders. For example, the great
Rose family, as we receive it, embraces three suborders ; one of
them represented by the Plum, Peach, Almond, &c. ; a second, by
the Pear, Quince, Hawthorn, and the like ; and the third, by the
Rose itself and its immediate relatives. Some botanists receive
these three as so many orders : we regard them as suborders, be-

31

3G2 PRINCIPLES OK CLASSIFICATION.

cause of the strong family likeness which pervades the whole, and
of the transitions between them. In the larger of these suborders,
or the proper Rose family, Ave recognize three trihes : one repre-
sented by the Rose genus itself; one by the Bramble genus, with
the Strawberry, Cinquefoil, Avens, &c. ; and the third by Spiraea
and its near relations. And, again, the second and larger of these
embraces genera which are ditferent enough to be ranked under
several subtribes.

706. Upon the same principles, groups may be interposed between
the orders and the classes, of which the highest kind will take the
name of Subclasses. And even above classes we have the most
comprehensive division of all plants into a higher and a lower grade
or Series (98) ; which brings us up to the vegetable Kingdom,
one of the three great departments of Nature.

707. To exhibit the whole sequence or stages of natural-history
classification, so that the student may see the relative rank of groups,
designated by the terms which have now been explained, they are
here presented, arranged in a descending series, beginning with the
primary division of natural objects into kingdoms, and indicating by
small capitals those of fundamental importance and universal use in
classification.

Kingdoms,
Scries,

Classes,

Subclasses,

Orders or Families,
Suborders,
Tribes,

Subtribes,
Genera,

Subgenera,
Species,

Varieties,

Individuals.

708. Characters. An enumeration of the distinguishing marks, or
points of difference between one class or order, &c. and the others,
is termed its character. Characters accordingly properly embrace
only those points which are common to all plants of the group, but
'not to the other groups of the same rank. The characters of
classes, &c. are restricted to those general peculiarities of structure
upon which these great groups are established : the ordinal charac-
ter recites the particulars in which the plants it comprises differ

CHARACTERS. BINOMIAL NOMENCLATURE. 3G3

from all others of the class ; the generic character enumerates
those points which distinguish the plants of the genus in question
from all others of the same order or suborder ; the specific character
indicates the differences between species of the same genus ; — to
which in botanical works more or less of general description, accord-
ing to the plan and extent of the work, is generally added.

709. A complete system of Botany will therefore comprise a
methodical distribution of plants according to their organization,
with their characters arranged in proper subordination ; so that the
investigation of any one particular species will bring to view, not
only its name (which separately considered is of little importance),
but also its plan of structure, both in general and in particular, its
relationships, essential qualities, and whole natural history. The
classification and the method of investigation in natural history con-
stitute not only the most complete arrangement known for the col-
location of a vast amount of facts, but also the best system of prac-
tical logic ; and the study exercises and sharpens at once both the
powers of reasoning and of observation, more, probably, than any
other pursuit. As a system for collocating facts for convenient ref-
erence, a great practical advantage of natural history is secured by
its happily devised

710. Binomial Nomenclature. Since the time of Linnaeus, who in-
troduced the system, the scientific name of every plant is expressed
by two words, viz. by the name of its species appended to that of
its genus, each of a single word. That of the genus, i. e. the ge-
neric name, is a substantive ; that of the species, or the specific
name, is an adjective adjunct. The same name is never employed
for different genera ; the same specific name is not available for
more than one species of the same genus, but may be used in any
other genus. A few thousand names accordingly serve completely
to designate something like 8,000 genera and nearly 100,000 species
of plants, in a manner which obviates all confusion, and does not
greatly burden the memory. The generic name of a plant answers
to the surname of a person, as Brown or Jones ; the specific name
answers to the baptismal name, as John or James. Thus, Que reus
alba is the botanical appellation of the White Oak ; Quercus being
the substantive name for the genus, and alba (white) the adjec-
tive name for this particular species ; while the Red Oak is named
Quercus rubra ; the Scarlet Oak, Quercus coccinea ; the Live Oak,
Quercus virens ; the Bur Oak, Quercus macrocarpa ; and so on.

3(34 • PRINCIPLES OF CLASSIFICATION.

The scientific names of plants are all Latin or Latinized ; and that
of the species always follows that of the genus.

711. Generic names in botany are derived from various sources.
Those of plants known to the ancients generally preserve their clas-
sical appellations ; as, for example, Quercus, Fagus, Corylus, Prunus,
Myrtus, Viola, &c. For plants since made known, even their barba-
rous names are often adopted, when susceptible of a Latin termina-
tion, and not too uncouth ; for example, Theea and Coffcea, for the
Tea and Coffee plants, Bambusa for the Bamboo, Yucca, Negundo,
&c. But more commonly, new generic names, when wanted, have
been framed by botanists to express some botanical character, habit,
or obvious peculiarity of the plants they designate ; such as Arena-
ria, for a plant which grows in sandy place;; Dentaria, for a
plant with toothed roots ; Lunaria, for one with moon-like pods ;
Sanguinaria, for the Bloodroot with its sanguine juice ; Crassula,
for some plants with remarkably thick leaves. These are instances
of Latin derivatives ; but recourse is more commonly had to the
Greek language, in which compounds of two words are much more
readily made, expressive of peculiarities ; such as Menispermum, or
Moonseed ; Lithospermum, for a plant with stony seeds ; Melanthium,
for a genus whose flowers turn black or dusky ; Epidendrum, for
certain Orehideous plants which grow upon trees ; Liriodendron,
for a tree which bears lily-shaped flowers, &c. Genera are also
dedicated to distinguished persons ; a practice commenced by the
ancients ; as Pceonia, which bears the name of Pa^on, who is said to
have employed the plant in medicine ; and Euphorbia, Artemisia, and
Asclepias are also example^ of the kind. Modern names of this
kind are freely given in commemoration of botanists, or of persons
who have contributed to the advancement of natural history. Mag-
nolia, Bignonia, Lobelia, and Lonicera, dedicated to Magnol, Big-
non, Lobel, and Lonicer, are early instances ; Linncea, Tournefortia,
Jtissicza, Hatter ia, and Gronovia, bear the names of the most cel-
ebrated botanists of the eighteenth century ; and at the present day
almost every devotee of the science is thus commemorated.

712. Specific names are adjuncts, and mostly adjectives, adopted
on similar principles. Most of them are expressive of some char-
acteristic or obvious trait of the species ; as, Magnolia grandijiora,
the Large-flowered Magnolia ; M. macrophylla, the Large-leaved
Magnolia ; M. glauca, which has the foliage glaucous or whitened
underneath ; or Viola tricolor, from the three-colored corolla of the

NATURAL AND ARTIFICIAL SYSTEMS. 365

Pansy ; V. rostrata, a remarkably long-spurred species ; V. rotundi-
folia, with rounded leaves ; V. lanceolata, with lanceolate leaves ;
V. pedata, with pedately parted leaves ; V. primulcefolia, where the
leaves are compared to those of the Primrose ; and V. pubescens,
with pubescent or hairy herbage. Sometimes the specific name re-
fers to the country which the plant inhabits or was first found in, as
Viola Canadensis, the Canadian Violet ; or to the station where it
naturally grows, as V. palu'stris (Marsh Violet). Sometimes it com-
memorates the discoverer or describer, when it rightly takes the
genitive form, as Viola Muhlenbergii, V. Nuttallii, &c. When com-
memorative names are given merely in compliment to a botanist un-
connected with the discovery or history of the plant, the adjective form
is px-eferred ; as, Carex Torreyana, C. Hookeriana, &c. : but this rule
is not universally followed. Specific names are sometimes substantive ;
as, Magnolia Umbrella, Ranunculus Flammula, Hypericum Sarothra,
Linaria Cxjmbalaria, &c. (most of these being old generic names
used as specific) ; when they do not necessarily accord with the
genus in gender. These, as well as all specific names taken from
persons or countries, are to be written with a capital initial letter.

713. Varieties may be designated by names when they are re-
markable enough to require it. The name of the variety, when
used at all, follows that of the species, and is formed on the same
plan. Subgenera need to be designated by names, which are sub-
stantive, and on the same principle as generic names. These are
convenient to refer to, but are not a part of the proper name of
a plant, which is that of the genus and species only.

714. The names of genera and species are the same in all botani-
cal systems, and therefore are properly alluded to here. But those
of orders, and all other groups higher than genera, vary in plan
with the system adopted. Classifications are of two sorts, viz.

715. Natural and Artificial Systems. A natural system carries out
in practice as perfectly as possible the principles sketched in this
chapter, arranging all known species in groups of various grades in
view of their whole plan of structure, so placing each genus, tribe,
order, &c. next to those it most resembles in all respects. An arti-
ficial system arranges the genera by some one character, or set of
characters, chosen for convenience, disregarding other considerations.
It aims only to provide an easy mode of ascertaining the names of
plants, and does not attempt to express their points of resemblance
generally, but serves nearly the same purpose as a dictionary.

31*

3GG

THK PRINCIPLES OP

716- Artificial systems are no longer used in botany, except as
keys cr helps in referring plants to their proper groups in natural
arrangements. But the celebrated Artificial System of Linnaeus
so long prevailed, and has exerted so great an influence over the
progress of the science, that it is still desirable for the student to
understand it. It will therefore be explained, after we have illus-
trated the principles of the Natural System of Botany.

CHAPTER II.

OF THE NATURAL SYSTEM OF BOTANY.

717. The object proposed by the Natural System of Botany is
to bring together into groups those plants which most nearly resem-
ble each other, not in a single and perhaps relatively unimportant
point (as in an artificial classification), but in all essential particu-
lars ; and to combine the subordinate groups into successively more
comprehensive natural assemblages, so as to embrace the whole
vegetable kingdom in a methodical arrangement. All the charac-
ters which plants present, that is, all their points of agreement or
difference, are employed in the classification ; those which are com-
mon to the greatest number of plants being used for the primary
grand divisions ; those less comprehensive, for subordinate groups,
&c. ; so that the character, or description of each group, when fully
given, actually expresses the main particulars in which the plants it
embraces agree among themselves, and differ from other groups of
the same rank. This complete analysis being carried through the
system, from the primary divisions down to the species, it is evident
that the study of a single plant of each group will give a correct
general idea of the structure, habits, and even the sensible proper-
ties, of the whole.

718. For it is evident that the relationships of plants are real;
that there is not only a general plan of vegetation (with which the
student has already become familiar), but also a plan in the relations
which subsist between one plant and another; that the species sustain
to each other the relation of parts to a whole, — so that this whole,
or vegetable kingdom, is an organized system. And this system, as

THE NATURAL SYSTEM OK CLASSIFICATION. 3G7

far as comprehended, may be to a good degree expressed in our
classification. This idea of plan and system in nature supposes a
Planner, or a mind which has ordered things so, with intelligence and
purpose •, and it is this plan, or its evidences and results, which the
naturalist is endeavoring to investigate. The botanist, accordingly,
does not undertake to contrive a system, but he strives to express in
a classification, as well as he can, the System of Nature, or, in other
words, the Plan of the Creator in the Vegetable Kingdom.

719. " So there can be only one natural system of botany, if by
the term we mean the plan according to which the vegetable crea-
tion was called into being, with all its grades and diversities among
the species, as well of past as of the present time. But there may
l>e many natural systems, if we mean the attempts of men to inter-
pret and express the plan of the vegetable creation, — systems
which will vary with our advancing, knowledge, and with the judg-
ment and skill of different botanists, — and which must all be very
imperfect. They will all bear the impress of individual minds, and
be shaped by the current philosophy of the age. But the endeavor
always is to make the classification a reflection of Nature, as far as
any system can be which has to express such a vast and ever in-
creasing array of facts, and most various and intricate relations, in
a series of definite propositions, and have its divisions and subdi-
visions following each other in some fixed order." Our so-called
natural methods must always fail to give more than an imperfect
and considerably distorted reflection, not merely of the plan of the
vegetable kingdom, but even of our knowledge of it ; and every
form of it yet devised, or likely to be, is more or less artificial, in
some of its parts or details. This is inevitable, because, —

720. (1st.) The relationships of any group cannot always be right-
ly estimated before all its members are known, and their whole
structure understood ; so that the views of botanists are liable to be
modified with the discoveries of every year. The discovery of a
single plant, or of a point of structure before misunderstood, has-
sometimes changed materially the position of a considerable group
in the system, and minor alterations are continually made by our in-
creasing knowledge. (2d.) The groups which we recognize, and dis-
tinguish as genera, tribes, orders, &c, are not always, and perhaps
not generally, completely circumscribed in nature, as Ave are obliged
to assume them to be in our classification. This might be expected
from the nature of the case. For the naturalist's groups, of what-

3C8 THE PRINCIPLES OF

ever grade, are not realities, but ideas ; their consideration involves
questions, not of things, between which absolute distinctions might
be drawn, but of degrees of resemblance, which may be expected to
present infinite gradations. (3d ) Although the grades of affinity
among species are most various, if not wholly indefinite, the nat-
uralist reduces them all to a few, and treats his genera, tribes, &c.
as equal units, or as distinguished by characters of ahout equal value
throughout, — which is far from being the case. (4th.) The nat-
uralist in his works is obliged to arrange the groups he recognizes in
a lineal series ; but each genus, or order, &c. 'is very often about
equally related to three or four others ; so that only a part of the
relationship of plants can practically be indicated in the published
arrangement.

721. The natural system as sketched by Bernard and A. L. Jus-
sieu, and improved by the labors of succeeding botanists, essentially
consists of an arrangement of the known genera according to their af-
finities under two hundred or more natural orders, and of these under
a few great types or classes. What is now most wanted to complete
the system is a truly natural arrangement of the orders under the
great classes, like that of the genera under their respective orders.
Until this is done, the series in which the orders follow one another
in botanical works must not be regarded as a part of the system of
nature. Different authors adopt different modes of arranging them ;
and all of them that a learner could use are avowedly more or less
artificial.

722. Omitting all historical details and statements of more or less
conflicting views, we will briefly sketch the outlines of the principal
divisions of the vegetable kingdom, according to the natural system
as we now practically receive it. In explaining the principles of
classification, we proceeded from the individual to the class. In ex-
amining the actual construction of the system of botany, it is simpler
to regard the vegetable kingdom as a whole, and show how it is nat-
urally divided and subdivided. This is the course a student must
follow with an unknown plant before him, which he wishes to refer
first to its class, then to its order, and finally to its genus and
species.

723. The long and complex series, stretching from the highest
organized vegetable down to the simplest and minutest of the Fungi
and Alga}, is most naturally divided, as we have already seen, into
two parts, forming a higher and a lower grade or series (98), viz.

THE NATURAL SYSTEM OF CLASSIFICATION. 3G9

Series I. PwuenogAmous (or Phanerogamous) or Flowku-
ixg Plants (114, 117), which produce flowers and seeds, the latter
containing a ready-formed embryo.

Series II. Cryptooamous or Floaverless Plants (113,
117, 651), whose organs of reproduction are not flowers, but some
more or less analogous apparatus, and which are propagated by
spores or specialized cells.

724. "We have next to consider how these two series may be
themselves divided, in view of the most general and important points
of difference which the plants they comprise exhibit. Whenever
Phamogamous plants rise to arborescent forms, a difference in port
and aspect at once arrests attention; that which distinguishes our
common trees and shrubs from Palms and the like (Fig. 184). On
examination, this is found to accompany a well-marked important
difference in the structure of the stem or wood, and in its mode of
growth. The former present the exogenous, the latter the endoge-
nous structure or growth (200 - 203, 207, &c). This difference is
ecmally discernible, if not so striking, in the annual or herbaceous
stems of these two sorts of Phamogamous plants. A difference is
aho apparent in their foliage; the foimer generally luue reticulat-
ed, or netted-veined, the latter parallel-veined leaves (27G). The
leaves of the former usually fall off by an articulation ; those of the
latter decay on the stem (309, 310). The Phamogamous series,
therefore, divides into two great classes, namely, into EXOGENOUS
and Endogenous plants, more briefly named Exogeks and Endo-
gens. The difference between the two not only pervades their
whole port and aspect, but is manifest from the earliest stage, in the
plan of the embryo. The embryo of Exogens, as already shown, is
provided with a pair of cotyledons (or sometimes with more than
one pair) ; that of Endogens, with only one ; whence the former are
also termed Dicotyledonous, and the latter Monocotyledo-
nous plants (128, 641-G43) : names introduced by Jussieu, the
father of this branch of botany.* Taking these divisions for classes,
we have

* There is, perhaps, no real and complete exception to the coincidence of an
exogenous stem with a dicotyledonous (or polycotyledonous) embryo, and of an
endogenous stem with a monocotyledonous embryo. Nyctaginaceous plants
and some others have a few vascular bundles scattered through their pith, but
the rest of the wood is regularly exogenous. The stalk of Podophyllum imi-
tates an Endogen, but the subterranean rootstock is truly exogenous, as it should

370 THE PRINCIPLES OF

Class I. Exogenous on Dicotyledonous Plants; thoe
with endogenous stems, netted-veined leaves, and dicotyledonous (or
rarely polyeotyledonous) embryo ;

Class II. Endogenous or Monocotyledonous Plants;
those with endogenous stems, mostly parallel-veined leaves, and
monocotyledonous embryo.

725. "Without entering here into a particular explanation of the
diversities of structure which Cryptogamous plants present, suffice
it to say that they exhibit three grades of simplification as to their
vegetation, which appear to correspond with three different modes
of fertilization. Plants of the highest grades of the Cryptogamous
series have wood and ducts in their composition (i. e. they are vascu-
lar plants, 111), and display the ordinary type of vegetation, viz.
with an axis or stem, bearing distinct foliage. But this stem in
structure is neither endogenous nor exogenous, and grows from the
apex only, having no primary root ; whence these vascular Flower-
less plants have been called Acrogens, or Acrogenous plants.
Of this kind are Ferns, Lyeopodiaceie, Equisetacese or Horsetails,
&c. These plants, it appears, produce their organs analogous to
flowers, and have their fecundation effected, once for all, upon the
infantile or germinating plantlet, and the result is the origination of
a bud, which develops into the adult plant; and that bears the fruit,
in the form of spore-cases and spores (6G3). Here then are the
characters of

Class HI. Acrogenous Plants; Cryptogamous plants, with
a distinct axis and mostly with foliage, having wood and ducts in
their composition: fertilization occurring upon a transient germinat-
ing plantlet, and giving rise to the adult plant.

726. The other Cryptogamous plants, being composed of paren-
chyma only, (or with slight exceptions,) are called Cellular plants
(111). Among them the Mosses and Liverworts present for the
most part the ordinary plan of vegetation ; their organs analogous
to flowers appear in the adult plant ; and the fertilization of the
pistillidium gives origin to a sporangium in which a multitude of
spores, capable of germination, are developed. These compose

Class IV. Axopiiytes : cellular Cryptogamous plants, with
distinct stem and foliage, or sometimes these parts confluent into a

be. The trunks or rootstocks of Water-Lilies appear to be endogenous ; but
those who have investigated them minutely, declare that they arc not really so.

THE NATURAL SYSTEM OK CLASSIFICATION. 371

frond, composed of parenchyma alone : fertilization giving rise to a
sporangium filled with spores.

727. The remaining and lower grade consists of plants such as
Lichens, Seaweeds or Algie, and Fungi, which exhibit no clear dis-
tinction into stem, root, and leaves, but consist of single cells or rows
of cells in their lowest grades, and in the higher, of masses of cells
disposed in almost every shape, but tending mostly to flat strata or
expansions ; hence the vegetation is termed a thallus (or bed), and
this word gives a name to the class, viz.

Class V. Thallophytes : cellular Cryptogamous plants with
no distinction of axis and foliage ; their spores mostly directly fer-
tilized (as explained in another place, G56-GG1).

728. These five classes are unequal in extent and diversity ; the
Exogenous class containing much the largest number of orders ; the
Endogens also comprising a considerable number ; the others com-
prise few orders or main types, but are most of them very rich
in tribes, genera, and species.

729. Only the first or highest class presents such marked diver-
sity of type among the plants it comprises as to call for the estab-
lishment of subclasses, that is, of groups of such importance as to
raise the question whether they should not be regarded as classes.
This question is raised by the peculiarities of Conifene (Pines, Cy-
presses, the Yew, &c), and by the tropical order of Cycadacea? ; in
which, not only are the flowers reduced to the greatest simplicity,
but the fertile ones consist of naked ovules merely, borne on the
margins or surface of a sort of open leaf, or else of an ovule, without
anything answering to a pistil at all. But as these plants are truly
exogenous and dicotyledonous (or often polycotyledonous), the better
opinion is that they should be ranked under the Exogenous or
Dicotyh-donous class, as a subclass. So that, while the main body
of the first class consists of

Subclass I. Axgiospermous Exogexs : viz. those with
proper pistils enclosing their ovules in an ovary, in the ordinary
manner ; the pollen to fertilize the ovules received upon a stigma
(420, 559, 574), — the others form the

Subclass II. Gymnosi'ERmous Exogexs : those with naked
ovules and seeds (as the name denotes), which are fertilized by
direct application of the pollen (5G0, 573, 625).

730. The general plan of the classes and subclasses .may be pre-
sented in one view, as in the subjoined synopsis.

o72

THE NATURAL CLASSICS.

1 I 2
to to 3

02

ILLUSTRATIONS OF THE NATURAL ORDERS. 373

731. The arrangement and general character of the principal
orders under each class form the subject of the ensuing chapter.
Before entering upon it, the

732. Nomenclature of Orders, Tribes, &C. requires some explanation.
The names of such groups are in the plural number. As a gen-
eral rule, the name of an order is that of some leading or well-known
genus in it, prolonged into the adjective termination acece. Thus,
the plants of the order which comprises the Mallow (Malva) are
called Malvacece ; that is, Plantce Malvaceae, or, in English, Malva-
ceous plants : those of which the Rose (Rosa) is the well-known
representative are Rosacea, or Rosaceous plants, &c. Some few
ordinal names, however, are differently formed, and directly indicate
a characteristic feature of the group ; as, for instance, Leguminosce,
or the Leguminous plants, such as the Pea, Bean, &c, whose fruit
is a legume (610) ; Umbelliferce, or Umbelliferous plants, so named
from having the flowers in umbels ; Composites, an order having
what were termed compound flowers by the earlier botanists (394) ;
Labiates, so called from the labiate or two-lipped corolla which
nearly all the species exhibit ; Cruciferce, which have their four
petals disposed somewhat in the form of a cross (Fig. 405).

733. Suborders, tribes, and all other groups between orders and
genera, bear names framed upon the same principles, that is, they
are plural, substantively-taken adjectives, derived from the name of
some characteristic genus of the group. Thus the genus Rosa
gives name to a particular tribe, Rosea, of the order Rosacea ; the
genus Malva to the tribe Malvece, of the order Malvacece, &c, — the
termination in acece being avoided, because reserved for ordinal
names.

CHAPTER III.

ILLUSTRATIONS OF THE NATURAL ORDERS OR FAMILIES.

734. Some authors (such as Jussieu and Endlicher) commence

with the lower extremity of the series, and end with the higher ;

while others (as De Candolle) pursue the opposite course, beginning

with the more perfect Flowering plants, and concluding with the

32

374 ILLUSTRATIONS OF THE NATURAL OHDKUS.

lowest grade of Flowerless plants. The first mode possesses the
theoretical advantage of ascending by successive steps from the
simplest to the most complex structure ; the second, the great prac-
tical advantage of beginning with the most complete and best under-
stood, and proceeding gradually to the most reduced and least
known forms, or, in other words, from the easiest to the most dif-
ficult ; and is therefore the best plan for the student.

735. Until the orders shall have been successfully associated into
natural alliances or superior groups, (of whatever name,) it is most
convenient to follow De Candolle's arrangement of them, in a gen-
eral way, with such minor alterations as may be called for. The
principal Floras now in use are arranged upon this general method.
It commences with the Exogenous class, with those orders of it
which are generally provided with complete flowers, and which ex-
hibit the floral organs in the most normal condition, according to
our theory of the blossom (Chap. IX., Sect. I. - III.), that is,
which have most of the several parts free and separate. It pro-
ceeds to those which are characterized by the union or consolida-
tion of their floral organs, and then to those which are reduced or
simplified by the suppression or obliteration of parts, ending with the
Gymnospermous subclass, the flowers of which are extremely simpli-
fied. The Endogenous class succeeds, with a somewhat analogous
arrangement, ending with Grasses ; and the classes of the Cryp-
togamous series follow in the order of their rank.

736. The following cursory sketch takes in the principal orders,
freely omitting, however, small and obscure ones, as well as certain
well-characterized groups which have no interest to the ordinary
student, and no indigenous, naturalized, or commonly cultivated rep-
resentatives in the United States. Certain exotic orders are also
omitted from the synopsis of the classes or large divisions, for greater
simplicity, but are briefly mentioned in their proper place. Fuller
accounts of the natural orders, and of their systematic arrangement,
structure, properties, &c, must be sought in more extensive works,
such as Lindley's Vegetable Kingdom, De Candolle's Prodromus, &c.
As applied to the botany of this country, what is essential is comprised
in the Manual of the Botany of the Northern United States, by the
present writer, and in similar Floras. The characters of the orders,
&c. are drawn up in ordinary botanical language. For explanation
of the technical terms used, the reader may consult the Glossary at
the end of the volume.

EXOGENOUS Oil DICOTYLEDONOUS PLANTS. 375

Series I. Flowering or Phjenogamous Plants.

Plants furnished with flowers (essentially consisting of stamens
and pistils), and producing proper seeds.

Class I. Exogenous or Dicotyledonous Plants.

Stem consisting of a distinct bark and pith, which are separated
by an interposed layer of woody fibre and vessels, forming wood in
all perennial stems : increase in diameter effected by the annual
deposition of new layers between the old wood and the bark, which
are arranged in concentric zones and traversed by medullary rays.
Leaves commonly articulated with the stems, their veins branching
and reticulated. Sepals and petals, when present, more commonly
in fives or fours, and very rarely in threes. Embryo with two (or
rarely more) cotyledons.

Subclass 1. Angiospermous Exogenous Plants.
Ovules produced in a closed ovary, and fertilized by the action of
pollen through the medium of a stigma. Embryo with a pair of op-
posite cotyledons. (For convenience, the very numerous orders of
this subclass are divided into those with polypetalous, monopetalous,
and apetalous flowers. This holds in a general way ; but a good
many genera and species of mainly polypetalous, and some of mono-
petalous orders, are apetalous. The character of the following divis-
ion must therefore be regarded as liable to exception in this respect.
For example, many of the genera of the first order have apetalous
fiWers. — The earlier groups of this division are mostly hyp°gy-
nous ; those that succeed, perigynous ; the last are epigynous.)

Division I. Polypetalous Exogenous Plants.
Calyx and corolla both present ; and tlie petals distinct.

Conspectus of the Orders.
Group 1. Ovaiies several or numerous (in a few cases solitary), distinct, when
in several rows sometimes cohering in a mass, but not united into a com-
pound pistil. Petals and stamens hypogynous. Seeds albuminous.
* Stamens or pistils (one or both) numerous or indefinite.
Herbs without stipules. Ranunculacf.vW.

Shrubs or trees. Corolla imbricated in the bud. Maqnouacejb.

Shrubs or trees. Corolla valvatc in the bud. Anoxace^k.

376 ILLUSTRATIONS OF Tllli NATURAL ORDKRS.

* * Stamens few or definite, mostly before the petals. Pistils one or few.
Climbing plants. Diuecious or monoecious. Mexi sperm ack;e.

Not climbing. Flowers perfect. Anthers opening by valves. Berberidacea:.

Group 2. Ovaries several and distinct, or perfectly united into a compound
pistil of several cells. Embryo enclosed in a sac at the end of the albu-
men, or^ in Nelumbium, without albumen. Aquatic herbs.

Carpels distinct, immersed in a dilated top-shaped torus. Nelumbiace^s.

Carpels united into a several-celled and many-ovuled ovary. Nymph^eacea:.

Carpels distinct and free. Stamens 6 -18. Cabombacea:.

Group 3. Ovary compound, 5-celled, with the placentas in the axis. Sta-
mens hypogynous, indefinite. Seeds numerous, anatropous, albuminous,
with a small embryo. Marsh herbs, with singular pitcher-shaped or
tubular leaves. Sarraceniacea:.

Group 4. Ovary compound, with parietal placenta?. Petals and sepals 2 or 4,
deciduous Stamens hypogynous. Flower unsymmetrical. Embryo small,
in copious albumen, or coiled when there is no albumen.
Seeds albuminous : embryo small or minute.

Polvandrous : flower regular. Juice milky or colored. Papaveracea:.

Diadelphous or hexandrous : flower irregular. Fumariacea:.

Seeds without albumen : styles and stigmas united into one.
Pod two-celled. Radicle folded on the cotyledons. Crucifkra:.

Pod one-celled Embryo rolled up. . Capparidacea:.

Seeds without albumen : styles or stigmas several. Resedacea:.

Group 5. Ovary compound, with parietal placentae. Floral envelopes mostly

5-merous ; calyx persistent. Stamens hypogynous. Seeds albuminous.
Anthers (5) adnate, introrse, connate. Corolla irregular. Violacea;.

Anthers extrorsc, or innate, distinct. Corolla regular.

Vernation circinatc. Petals marccsccnt. Droseracea:.

Vernation straight. Petals usually caducous. Cistacea:.

Group 6. Ovary compound, with the placenta? parietal, or 2 - 5-cellcd from
their meeting in the axis Stamens hypogynous. Seeds with a straight
embryo and little or no albumen.

Sterile filaments or a lobed appendage before each petal. Parnassiaceje.
Sterile filaments none : leaves opposite.

Stipules none ; leaves dotted. Stamens unsymmetrical. Hyfericacea:.

Stipules present : leaves dotless. Stamens symmetrical. Elatinacea:.

Group 7. Ovary compound, one-celled Avith a free central placenta, or 2-
sevcral-celled with the placenta in the axis. Calyx free or nearly so.
Stamens hypogynous or perigynous. Embryo peripheric, coiled more or
less around the outside of mealy albumen.

Petals and stamens numerous. Ovary many-celled. Mesembryanthemacea:.
Petals 3-5 or 6, sometimes wanting. ■»

Floral envelopes symmetrical. Stamens 10 or fewer. Caryophyllacea:.

Floral envelopes unsymmetrical, or stamens many. Portulacace/E.

EXOGENOUS OR DICOTYLEDONOUS TEANTS. 377

Group 8. Ovary compound and several-celled, with the placenta in the axis ;
or the numerous carpels more or less coherent with cacli other or with a
central axis. Calyx free from the ovary, with a valvate aestivation. Sta-
mens mostly indefinite, monadelphous, or polyadelphous, inserted with the
petals into the receptacle or base of the petals.

Anthers l-celled, reniform. Stamens monadelphous. Malvaceae.

Anthers 2-celled. Fertile stamens few, monadelphous. Byttneriace^e.

Anthers 2-cclled. Stamens polyandrous or polyadelphous. Tiliacea;.

Group 9. Ovary compound, with two or more cells, and the placentae in the
axis, free from the calyx, which is imbricated in aestivation. Stamens in-
definite, or twice as many as the petals, usually monadelphous, hypogy-
nous — Trees or shrubs.

Leaves simple, not dotted. Stamens indefinite. Camelliace.e.

Leaves pellucid-punctate, mostly compound. " Aurantiace.e.

Leaves compound, dotlcss. Stamens 10 or less, monadelphous.

Seeds single in each cell, wingless. Meliace^c.

Seeds several in each cell, winged. Cedrelack^e.

Group 10. Ovary compound, or of several carpels adhering to a central axis,
(or rarely distinct in the last two), free from the calyx, which is mostly im-
bricated in aestivation. Stamens as many or twice as many as the petals,
inserted on the receptacle, often monadelphous at the base. Embryo large.
Albumen little or hone. Flowers perfect, except in some Itutaceae.

* Flower irregular and unsymmetrical. Albumen none.
Stamens united over the pistil. Ovules several in each cell. Balsaminace*;.
Stamens distinct. Ovules single in each cell. Trop.eolace;e.

* * Flower regular and mostly symmetrical.
Leaves not punctate with transparent dots.

Calyx valvate. Albumen none : cotyledons very thick. Limnantiiace^e.
Calyx imbricated in aestivation.
Embryo conduplicatc : the radicle bent down on the

convolute cotyledons. Geraniace^e.

Embryo straight or nearly so.

Stamens (fertile) 5. Leaves simple, entire. Linaceje.

Stamens 10. Leaves opposite, compound. Zygopiiyllaceje.

Stamens 10. Leaves alternate, mostly compound.

Ovules more than one in each cell. Oxalidace;e.

Ovules only one in each cell. Simarubace/E.

Leaves punctate with transparent dots. Rutace.e.

Group 11. Ovary one, or several and distinct or combined into one, with one
or rarely two ovules in each cell. Calyx free ; stamens more or less
perigynous, as many or twice as many as the petals. Embryo large :
albumen none. Shrubs or trees with a resinous or viscid-milky juice, and
mostly polygamous or dioecious flowers. Leaves not punctate. — Intem-
perate climates represented only by Anacardiace.e.
32*

3/8 ILLUSTRATIONS OF THE NATURAL ORDERS,

Gioup 12. Ovary compound, 1 -5-cellcd, with one or two ovules erect from
the base of the cells. Calyx free or partly adherent. Stamens as many as
the petals or sepals and opposite the former. Seeds anatropous, albumi-
nous. Woody plants, with a colorless juice. Flowers regular. Leaves
alternate.

Calyx obscure. Petals valvate, caducous. Embryo minute. VitacE/K.

Calyx more conspicuous than the petals, valvate. Rhamnackje.

Group 13. Ovary compound, 2-5-celled, with only one or two ovules in each
cell. Stamens as many as the petals and alternate with them, perigynous.
Seeds furnished with an arillus, albuminous, with a large straight embryo.
Woody plants, with regular flowers and simple leaves — Represented
mainly by Celastrace.*:.

Group 14. Ovary compound and 2-3-cclled, with one or two (rarely 3 or 4)
o\ules in each cell, free fiam the calyx, which is imbricated in activation.
Flowers often irregular, and sometimes unsymmetrical. Stamens definite,
hypogynous or perigynous. Shrubs, trees, or herbs. Leaves opposite or
alternate, not punctate.

Stamens distinct, inserted on a hypogynous or perigynous disk.
Embryo (except in Staphylca) variously curved or coiled, and

destitute of albumen Sapindace^e.

Stamens hypogynous, without a disk.
Stamens mostly monadelphous, 10.

Flowers regular. Embryo curved ; albumen none. Malpighiaceje.

Stamens monadelphous or diadelphous, 6 or 8. Flower irregu-
lar and unsymmetrical. Embryo straight in albumen. Polygalace;e.

Group 15. Ovary simple and solitary, free fiom the calyx; the fruit a pod.
Flower 5-merous, the odd sepal anterior. Corolla papilionaceous, irregu-
lar, or sometimes regular. Stamens monadelphous, diadelphous, or dis-
tinct, mostly perigynous. Seeds destitute of albumen

Stamens hypogynous, the anterior wanting. Stipules none. Krameriace^-:.
Stamens mostly perigynous. Fruit a legume. Leguminos^d.

Group 16. Ovaries one or several, cither simple and distinct, or combined
into a compound ovary witli two or more cells and the placentas in
the axis Petals and the distinct stamens perigynous. Seeds destitute of
albumen.

* Calyx free, although often enclosing the ovaries in its tube, except when the

latter are united, when it is adnate to the compound ovary, and the sta-
mens are indefinite.

Leaves alternate, stipulate. Cotyledons plane. Rosaceje.

Leaves opposite, not stipulate, nor pellucid-punctate. Calycantiiace.e.

Leaves opposite, not stipulate, pellucid-punctate. Myrtaceje.

* * Calyx free from the compound ovary. Stamens definite. Lythkace.e.

EXOGENOUS OR DICOTYLEDONOUS rLANTS. S~9

* * * Calyx-tube ndrnte to the compound ovary. Stamens definite.

Anthers opening by a pore at the apex. Melastomace^e.
Anthers opening longitudinally.

Stipules between the petioles. Leaves opposite. Rhizophora.CE/E.
Stipules none. Calyx valvate.

Cotyledons convolute. Fruit indehiscent, 1-celled. Combbetace^e.

Cotyledons plane. Fruit mostly 2 - 4-eelled. Onagbace^e.

Group 17. Ovary compound, one-celled, with parietal placentae. Petals and
(with one exception) stamens inserted on the throat of the calyx. Flowers
perfect, except in Papayaccas.

* Calyx adherent to the ovary.

Albumen none or very little Petals and stamens indefinite. Cactace.e.

Albumen very copious. Embryo minute. Stamens 5. Gbossulace.e.

Albumen present. Embryo rather large. Stamens indefinite. Loasace^e.

* * Calyx free from the ovary.
Flowers perfect. Stamens 5.

Stamens distinct and perigynous. Tubnebace^e.

Stamens monadelphous, adnatc to the gynophore. Passifloraceje.

Flowers dioecious. Stamens 10, on the corolla. Papayace^e.

Group 18. Ovary compound, one -several-celled, the placentae parietal (either
truly or falsely so). Calyx adnatc. Corolla frequently monopctalous.
Stamens mostly united either by their filaments or anthers. Flowers
dioecious or moncecious. Albumen none. Succulent or tender vines with
tendrils. Cucurbitace^e.

Group 19. Ovaries two or more, many-ovulcd, distinct, or partly, sometimes
completely, united, when the compound ovary is one-celled with parietal
placenta?, or 2 -many-celled with the placenta? in the axis. Calyx cither
fiee from the ovary or more or less adherent to it. Petals and stamens
inserted on the calyx ; the latter mostly definite. Seeds albuminous, nu-
merous.

Pistils of the same number as the sepals. Crassulace^e.

Pistils fewer than the sepals, more or less united. Saxifragace;e.

Group 20. Ovary compound, 2- (rarely 3-5-) celled, with a single ovule sus-
pended from the apex of each cell. Stamens usually as many as the pet-
als or the lobes of the adherent calyx. Embryo small, in hard albumen.

* Summit of the (often 2-lobed) ovary free from the calyx ; the petals and sta-

mens inserted on the throat of the calyx. Hamamelace.e.-

* * Calyx-tube entirely adherent to the ovary. Stamens and petals epigynous.
Fruit separable into two dry carpels. Flowers umbellate. Umbellifer.e.
Fruit drupaceous, usually of more than two carpels. Abaliace.e.
Fruit a 1 -2-cclled drupe. Flowers cymosc or capitate. Cobnace^e.

380

ILLUSTRATIONS OF THE NATURAL ORDERS.

737. Ol'd. Raniinculacea! {Crowfoot Family). Herbaceous, occa-
sionally climbing plants, with an acrid watery juice, and usually
palmately or ternately lobed

or divided leaves, without
stipules. Calyx of three to
six, usually five, distinct
sepals, deciduous, except in
Pajonia and Helleborus.
Petals five to fifteen, or
often none. Stamens indefi-
nite, distinct. Ovaries nu-
merous, rarely few or soli-
tary, distinct, in fruit becoming achenia (Fig. 566, 567) or follicles
(Fig. 579, 648, 649), or in Aetata a berry. Embryo minute, at the
base of firm albumen (Fig. 650, 610). — Ex. Ranunculus, the But-
tercup (Fig. 645), which has regular
flowers with petals. Clematis (Vir-
gin's Bower, which is the type of a
tribe), Anemone (Fig. 411), Hepatica
(Liver-leaf), &c. have no petals, but
the calyx is pctaloid. In these the flow-
ers are regular. The Larkspur (Fig.
398) and Monkshood (Fig. 401) have
the flowers irregular, and the Colum-
bine (Fig. 646) has petals in the form
of spurs. Actaea (Baneberry) and
one Larkspur have a solitary ovary :
in the latter the petals are consoli-
dated. Zanthorhiza (Yellow-root) has
only five or ten stamens. — The juice
of all Ranunculaceous plants is acrid, or even caustic : some, as the
Aconite, are virulent narcotico-acrid poisons.

738. Ord. DillcniflCerc, consisting chiefly of tropical and Australian
shrubs and trees, probably includes Crossosoma of Nuttall, a singu-
lar Californian genus. The order ranks between the preceding
and succeeding, but is nearer the former, from which it is known by
its arillate seeds.

FIG. 645. Vertical section of the flower of a Buttercup.

FIG 646. Flower and part of a leaf of Aquilegia Canadensis (Wild Columbine) 647 A
detached petal. 648 The five carpels of the fruit. 649 A separate follicle. 650. Vertical
section of the seed, showing the minute embr} o.

EXOGENOUS OK DICOTYLEDONOUS PLANTS.

381

739. Ord. Maglioliacere {Magnolia Family). Trees or shrubs;
with ample and coriaceous, alternate, entire or lobecl leaves, usually
punctate with minute transparent dots : stipules membranaceous, e\u
veloping the bud, falling off when the leaves expand. Flowers soli-
tary, large and showy. Calyx of three deciduous sepals, colored like
the petals ; the latter in two or more series of three. Stamens nu-
merous, with adnate anthers. Carpels either several in a single
row, or numerous and spicate on the prolonged receptacle ; in the
latter case usually more or less cohering with each other, and form-
ing a fruit like a cone or strobile. Seeds mostly one or two in each
carpel, sometimes drupaceous and suspended, when the carpels open,
by an extensile thread, composed of unrolled spiral vessels. Em-
bryo minute, at the base of homogeneous fleshy albumen. There
are three well-marked suborders, by many ranked as orders, viz. : —

740. Sllbord. MagnoliciE (Magnolia Family proper), characterized
principally as above, especially by the stipules and the imbricated
spiked carpels : — represented by Magnolia and Liriodendron. The
bark, &c. is bitter and aromatic, with some acridity.

741. Sllbord. Wintered ( Winter* s-Bark Family) has no stipules,
and the carpels occupy only a single verticil. These have more

FIG 651 Magnolia glauca 652. A stamen, seen from the inside, showing the two lobes of
the adnate anther 653 The carpels in fruit, persistent on the receptacle, and opening by the
dorsal suture ; the seeds suspended by their extensile cord of spiral vesseU.

382

ILLUSTRATIONS OK THE NATURAL ORDERS.

pungent and purer aromatic properties ; as in Illicium, the Star- Anise,
the seeds and pods of which furnish the aromatic oil of this name.

742. Sllbord. SchizaildreBE is monoecious or dioecious, with the pis-
tils spicate or capitate on a prolonged receptacle ; the stamens often
monadelphous. Leaves sometimes toothed, destitute of stipules. —
Ex. Schizanclra. These are mucilaginous, with little aroma.

743. Ord. Moniminceff is a small group, found in the southern
hemisphere, with pungent aromatic properties, most allied to the last
order according to Dr. Hooker (or to Calycanthacene, according
to Tulasne), but chiefly apetalous, and with opposite leaves.

744. Ord. AllOliaceE {Custard-Apple Family). Trees or shrubs,
with alternate entire leaves, destitute of stipules. Flowers large,
but dull-colored. Sepals 3. Petals 6, in two rows, valvate in aesti-

vation. Stamens numerous, in many rows, with extrorse anthers.
Carpels few, or mostly numerous and closely packed together, some-
times cohering and forming a fleshy or pulpy mass in the mature

FIG. 654. Flowering branch of the Pa paw (Asimlna triloba) of the natural size. 655 The
receptacle, with all but the pistils removed. 650 A stamen, magnified 657 View of three
baccate pods from the same receptacle (much reduced in size) ; one cut across, another length,
wise, to show the large bony seeds. 658. Section of the seed, to show the ruminated albumen.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

S83

fruit. Seeds one or more in each carpel, with a hard and brittle
testa: embryo minute, at the base of hard, ruminated albumen.
The four species of our so-called Papaw (Asimina) are our only rep-
resentatives of this chiefly tropical order, which furnishes the lus-
cious custard-apples of the East and West Indies, &c. Aromatic
properties, with some acridity in the bark, &c, prevail in the order.
Monodora yields the calabash-nutmeg.

745. Ord. MyristicaceJC {Nutmeg Family), consisting of a few tropi-
cal trees (which bear nutmegs), differs from Anonacea? in having
monoecious or dioecious and apetalous flowers, &c. The aril and the
albumen of the seeds are fine aromatics. The common nutmeg is
the seed of Myristica moschata (a native of the Moluccas) deprived
of the testa : mace is the aril of the same species. The ruminated
albumen is nearly peculiar to this family and the Anonaceoe.

746. Ol'd. McnispermacCiE (Moon seed Family). Climbing or twin-
ing shrubby plants, with alternate and simple palmately-veined leaves,
destitute of stipules ; and small flowers in racemes or panicles,
mostly dioecious, the parts commonly in two or more rows of three
or four each. Calyx of three to twelve sepals, in one to three rows,
deciduous. Petals as many as the sepals or fewer, small, or some-
times wanting in the pistillate flowers. Stamens as many as the
petals, and opposite them, or two to four times as many : anthers

often four-celled. Carpels usually several, but only one or two of
them commonly fructify, at first straight, but during their growth

FIG 659. Staminate flower of Menispermum Canadense. GGO. A stamen, with its four-
]obed anther. 6G1. A pistillate flower of the same. 6G2 A solitary fruit. 6G3. Two drupes
ou the same leceptaclc, cut across ; one through the pulpy exocarp only, the other through
the bony endocarp and seed. 664. A drupe divided vertically (the embryo here Li turued thf
wrong way) 6G5. The seed, and, C6G, the coiled embryo detached.

384

ILLUSTRATIONS OF THE NATURAL ORDERS.

often curved into a ring; in fruit becoming berries or drupes. Seeds
solitary, filling the cavity of the bony endoearp : embryo large,
curved or coiled in the thin fleshy albumen. — Menispermum, or
Moonseed (Fig. 413, 414, 659-666), Coceulus. The roots are
bitter and tonic (e. g. Colombo Root of the materia medica) ; but the
fruit is often narcotic and acrid ; as, for instance, the very poisonous
Coceulus Indicua of the shops, once used for rendering malt liquors
more intoxicating, and for stupefying fishes.

747. Orel. Bei'berillaceSB (Barberry Family). Herbs or shrubs,
with a -watery juice ; the leaves alternate, compound or divided, usu-
ally without stipules. Flowers perfect. Calyx of three to nine
sepals, imbricated in one to several rows, often colored. Petals as

many as the sepals and in two sets, or twice as many, often with a
pore, spur, or glandular appendage at the base. Stamens equal in

FIG 668 A shoot of Berberis vulgaris, the common Barberry 669 A flowering branch
from the axil of one of its leaves or spines, the following jear 670 An expanded flower.
671 A petal nectariferous near the base 672 A stamen ; the anther opening by uplifted
valves. 673 Cross-section of a young fruit. 674 Vertical section; the seeds attached at the
base 675 Vertical section of a seed enlarged, showing the large embryo with foliaceous
cotyledons and a taper radicle, surrounded by albumen 676 The embryo separate.

EXOGENOUS OK DICOTYLEDONOUS PLANTS. 385

number to the petals and opposite them, or rarely more numerous ;
anthers extrorse, the cells commonly opening by an uplifted valve
(Fig. 475, G72). Carpel solitary, often gibhous or oblique, forming
a one-celled pod or berry in fruit. Seeds sometimes with an aril:
embryo (often minute) surrounded with a fleshy or horny albumen.
— Ex. The Barberry, the sharp spines of which are transformed
leaves ; the Mabonias are Barberries with pinnated leaves. Caulo-
pbyllum thalictroides, the Blue Cohosh, is remarkable for its eva-
nescent pericarp (559), and the consequent naked seeds, which
resemble drupes Podophyllum peltatum (the Mandrake) presents
an exception to the ordinal character, having somewhat numerous
stamens, with anthers which do not open by valves ; but the latter
anomaly is also found in Nandina. The order is remarkable for
this valvular dehiscence of the anthers, and for the situation of both
the stamens and petals opposite the sepals. But this latter pecu-
liarity is easily explained away (4G1). The fruit is innocent or
eatable ; the roots, and also the herbage, sometimes drastic or poison-
ous, as in Podophyllum.

748. Ol'd. NcllimbiacCEC {Nclumbo Family). Aquatic herbs, with
large leaves and flowers, on long stalks arising from a prostrate
trunk or rhizoma, which has a somewhat milky juice : the leaves
orbicular and centrally peltate. Calyx of four or five sepals, decid-
uous. Petals numerous, inserted in several rows into the base of a
large and fleshy obconical torus, deciduous. Stamens inserted into
the torus in several rows : the filaments petaloid ; the anthers ad-
nate and introrse. Carpels several, separately immersed in hollows
of the enlarged flat-topped torus or receptacle (Fig. 427), each con-
taining a single anatropous ovule ; in fruit forming hard, round nuts.
Seed without albumen : embryo very large, with two fleshy cotyle-
dons, and a highly developed plumule. — Ex. The order consists of
the single genus Nelumbium, embracing two species ; one a native
of Asia, the other of North America. They are chiefly remarkable
for their large and showy leaves and flowers. The nuts are eatable.
It should be regarded rather as a suborder of the next.

749. Ol'd. Nympliacaceffi ( Water-Lily Family). Aquatic herbs, with
showy flowers and cordate or peltate leaves, arising from a prostrate
trunk or rhizoma, and raised on long stalks above the water, or
floating on its surface. Calyx and corolla of several or numerous
imbricated sepals and petals, which gradually pass into each other ;
persistent ; the latter inserted on the fleshy torus which surrounds

33

386

ILLUSTRATIONS OF THE NATURAL ORDERS.

or partly encloses and adheres to the pistil ; the inner series gradu-
ally changing into stamens. Stamens numerous, in several rows,
inserted into the torus with or above the petals ; many of the outer
filaments petaloid (Fig. 34-i), the adnate anthers introrse. Fruit in-
dehiscent, pulpy when ripe, many-celled, crowned with the radiate
stigmas ; the anatropous seeds covering the spongy dissepiments.
Embryo small, enclosed in a membranous bag, which is next the
hilum, and half immersed in the mealy albumen. Structure of the
trunk appearing rather endogenous than exogenous. — Ex. Nym-
pkcea, the White Water-Lily ; Nuphar, the Yellow Pond-Lily ; and

the magnificent Victoria of tropical South America, the most gigan-
tic and showy of aquatics, both as to its flowers and its leaves. Mu-
cilaginous plants, with slight astringency ; no important properties.

750. Ord. CabombaCCEB {Water-shield Family) is really merely a
simplified state of the last, with only one series of sepals and petals,

FIG. 077. Open flower, with a flower-bud and leaf of the White Water-Lily (Xymphaca
odorata) ; the inner petals passing into stamens. 078 A flower with all the parts around the
pistil cut away except one of the petaloid stamens, one intermediate, and one proper stamen.
C79 An inner petal, with the imperfect rudiments of an anther at the tip. 030. Transverse
suction of an ovary.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

187

definite stamens, or nearly so, with innate anthers, and the gynrocium
of few apocarpous, free, and few-ovuled pistils ; the ovules chiefly on
the dorsal suture. Brasenia and Cabomba are all the genera.

751. Ord. Sarmceniacca.' (Water-Pitcher Family). Perennial herbs,
growing in bogs ; the (purplish or yellowish-green) leaves all radical
and hollow, pitcher-shaped (Fig. 299, 300), or trumpet-shaped.
Calyx of five persistent sepals, with three small bracts at its base.
Corolla of five petals. Stamens numerous. Summit of the com-
bined styles very large and petaloid, five-angled, covering the five-
celled ovary, persistent. Fruit five-celled, five-valved, with a large
placenta projecting from the axis into the cells. Seeds numerous,
albuminous, with a small embryo. — Sarracenia, from which the
above character is taken, was the only known genus of the order,
until the recent discovery of Heliamphora in Guiana, which is apeta-
lous, its scape bearing several flowers ; as does that of a third genus,

FIG. G81 Brasenia peltata (Water-shield) ; the lower flower with the floral envelopes and a
part of the stamens removed. C82 A magnified stamen. 683 A magnified carpel. 684. The
same, divided lengthwise, showing the ovules attached to the outer or dorsal suture ! C85 Sec-
tion of a carpel, in fruit 6S6. A magnified seed, with half the outer integument removed,
displa} ing at the upper extremity the bag which contains the embryo. 687. A magnified sec-
tion through the middle of the albumen, &c. ; bringing to view the minute embryo enclosed
in its 6ac, 1., ing outside of the albun-.en, which forms the principal built of the seed.

388 ILLUSTRATION'S OK TIIK NATURAL ORDKKS.

Darlingtonia, Torr., recently discovered in California, with calyx and
corolla not very unlike those of Sarracenia, but without the umbrella-
like style. The species of Sarracenia are all Eastern North Amer-
ican. The affinities of the group are unsettled.

752. On!. PapavCMCea; (Poppy Family). Herbs with a milky or
colored juice, and alternate leaves without stipules. Calyx of two
(rarely three) caducous sepals. Corolla of four to six regular petals.
Stamens eight to twenty-four, or numerous. Fruit one-celled, with
two to five or numerous parietal placenta?, from which the valves
often separate in dehiscence. Seeds numerous, with a minute em-
bryo, and copious fleshy and oily albumen. — Ex. The Poppy (Pa-
paver), the leading representative of this small but important family,
is remarkable for the extension of the placenta? so as almost to divide

the cavity of the ovary into several cells, and for the dehiscence of
the capsule by mere chinks or pores under the edge of the crown

FIG. 688. Sanguinaria Canadensis (the Bloodroot). 689 The pod, divided transversely,
showing the parietal attachment of the seeds 690 Longitudinal section of a magnified seed
With its large rhaphe. showing the minute embryo, near the extremity of the albumen-
C91. Flower-bud of Eschscholtzia. 692. The calyptiiform calyx detached from the base 693.
Pod of the same.

EXOGENOUS OU DICOTYLEDONOUS PLANTS.

389

formed by the radiate stigmas. Eschscholtzia, now common in
gardens, is remarkable for the expanded apex of the peduncle, and
for the union of the two sepals into a cahjplra, like a candle-extin-
guisher, which, separating at the base, is thrown off by the expan-
sion of the petals. The colored juice is narcotic and stimulant.
That of the Poppy yields Opium. That of the Celandine and of the
Bloodroot (Sanguinaria) is acrid.

752'. Ord. FumariaCCft {Fumitory Family). Smooth herbs, with
brittle stems, and a watery juice, alternate dissected leaves, and no
stipules. Flowers irregular. Calyx of two sepals. Corolla of four
petals, in pairs ; the two outer, or one of them, spurred or sac-like
at the base ; the two inner, callous and cohering at the apex, includ-
ing the anthers and stigma. Stamens six, in two parcels opposite
the outer petals ; the filaments of each set usually more or less
united ; the middle one bearing a two-celled anther ; the lateral, with
one-celled anthers. Fruit a one-celled and two-valved pod, or round
and indehiscent. Seeds with fleshy albumen and a small embryo. —
Ex. Fumaria, Dicentra (Fig. 3G0-374), Corydalis.
A small and unimportant tribe of plants, chiefly re-
markable for their singular irregular flowers ; by
which, with their watery juice, they are distin-
guished, and that not very definitely, from the pre-
ceding family.

753. Ord. Cl'UCiferac (Mustard Family). Herbs,
with a pungent or acrid watery juice, and alternate
leaves without stipules ; the flowers in racemes or
corymbs, with no bracts to the pedicels. Calyx of
four sepals, deciduous. Corolla of four regular
petals, with claws, their spreading limbs forming a
cross (Fig. G94). Stamens six, two of them short-
er {tetradynamous, Fig. G95, 589). Fruit a pod
(called a silique when much longer than broad, or a
silicle when short, Fig. 703), which is two-celled
by a membranous partition that unites the two
marginal placentas, from which the two valves usually fall awaj\
Seeds with no albumen : embryo with the cotyledons folded on the
radicle. — Ex. The Water-Cress, Radish, Mustard, Cabbage, &c.
A very natural order, perfectly distinguished by having six tetra-
dynamous stamens along with four petals and four sepals, and by the

FIG. C94. Flower of Mustard. 605 The stamens and pistil.

33*

390

ILLUSTRATIONS OF THE NATURAL ORDURS.

peculiar pod. The peculiarity of the stamens is explained, and
the singular symmetry of the flower illustrated, on p. 243. All
these plants have a peculiar volatile acridity (and often an ethe-
real oil, which abounds in sulphur) dispersed through every part,
from which they derive their peculiar odor and sharp taste, and
their stimulant, rubefacient, and antiscorbutic properties. The roots
of some perennial species, such as the Horseradish, or the seeds of
annual species, as the Mustard, are used as condiments. In some
cultivated plants, the acrid principle is dispersed among abundance
of saccharine and mucilaginous matter, affording wholesome food ;
as the root of the Turnip and Radish, and the leaves and stalks

of the Cabbage and Cauliflower. None are really poisonous
plants, although some arc very acrid. Several species are in

FIG. fOG A Cruciferous flower. C97. The same, ivith tho calyx and corolla removed, show-
ing the tctradynamous stamens. C98. Silitjues of Arabis Canadensis ; one of them with one of
the valves detached, showing the seeds lying on the false partition ; the other valve also falling
away. 699. A magnified cross-section of one of the winged seeds, showing the embryo with
the radicle applied to the edge of the cotyledons (cotyledons decumbent). 700 The enibrjo
detached. 701 The raceme of Draba verna, in fruit 702. A cross-section of one of the «tf-
cles, magnified, exhibiting the parietal insertion of the seeds, and the false partition 703. A
silicic of Shepherd's Pur.-e (Capsella Bursa Tastoris) 704 The same, with one of the boat-
shaped valves removed, presenting a longitudinal view of the narrow partition, &c. 705. A
magnified cross-section of one of the seed =, showing the embryo with the radicle applied to the
siJo of the cotyledon (cotyledons incumbtnV.

EXOGENOUS Oil DICOTYLEDONOUS PLANTS.

391

cultivation, for their beauty or fragrance ; such as the Wall-flower,
Stock, &e.

754. Oi'd. CappfiridacCiC {Caper Family). Herbs, or in the tropics
often shrubs or trees ; differing from Cruciferse in the one-celled pod
(which is often stalked) being destitute of any false partition ; in the
kidney-shaped seeds ; and in the stamens, which, when six, are
scarcely tetradynamous, and are often more numerous. — Ex. Cle-
ome, Polanisia, Gynandropsis ; chiefly tropical or subtropical.
Many have the pungency of Crucifene, but are more acrid. Capers
are the pickled flower-buds of Capparis spinosa of the Levant, &c.
The roots and herbage or bark are hitter, nauseous, and sometimes
poisonous.

755. Old, RcSCdacCEB {Mignonette Family). Herbs, with a watery
juice, and alternate leaves without stipules, except a pair of glands
be so considered : the flowers in terminal racemes, small, and often
fragrant. — Calyx persistent, of four to seven sepals, somewhat
united at the base. Corolla of two to seven usually unequal and
lacerated petals, with broad or thickened claws (Fig. 377). A
fleshy disk is commonly present, enlarged posteriorly between the
petals and the stamens, and bearing the latter, which vary from
three to forty in number, and are not covered by the petals and
sepals in the bud. Fruit a one-celled pod, with three to six parietal
placental, three to six-lobed at the apex, where it opens along the

FIO. 706 Flower of Gynandropsis 707 Flower of Folanisia gravolcns 708. Fructified
ovary of t'ae same, a portion cut away by a vertical and '. i:i:outul section, to show the single
cell and two parietal placenta? 709 Cross-section of the ovary. 710 Section of the seed and
embryo.

392

ILLUSTRATIONS OF THE NATURAL ORDERS.

inner sutures, usually long before the seeds are ripe. Seeds several
or many, curved or kidney-shaped, with no albumen ; the embryo
incurved. — Ex. The common representatives of this order are the
Mignonette (Reseda odorata), prized for its fragrant flowers, and
the Weld (R. Luteola), which yields a poor dye.

756. Ord, FlaCOUrliacciC, a group of tropical shrubs and trees,
placed in this vicinity, is best known by Bixa Orellana, which yields
Arnatto, the orange-red dried pulp of the pod, surrounding the
seeds.

757. Ord. YiolilCea! ( Violet Family). Herbs (in tropical countries
sometimes shrubby plants), with mostly alternate simple leaves, on
petioles, furnished with stiptiles ; and irregular flowers (Fig. 39G,
397). Calyx of five persistent sepals, often auricled at the base.
Corolla of five unequal petals, one of them larger than the others
and commonly bearing a spur or a sac at the base : aestivation imbri-

cative. Stamens five, with short and broad filaments, which are
usually elongated beyond the (adnate introrse) anthers ; two of
them commonly bearing a gland or a slender appendage which is
concealed in the spur of the corolla : the anthers approaching each
other, or united in a ring or tube. Style usually turned to one side

FIG. 711. Viola sagittata 712. One of the stamens without appendage, Feen from within ;
and one furnished with a tpur-liko appendage on the back. 712 . A capsule which lias opened
and separated into three vahes; the calyx still persistent. 712'. A vertical sectiou of the
seed and embryo.

EXOGENOUS OR DICOTYLEDONOUS "PLANTS.

393

and thickened at the apex. Fruit a one-celled capsule, opening by
three valves, each bearing a parietal placenta on its middle. Seeds
several or numerous, anatropous, with a crustaceous integument, and
a straight embryo, nearly the length of the fleshy albumen (Fig. C04,
G05). — Ex. The Violet is the principal genus of this order; some
species, like the Pansy, are cultivated for the beauty of their flow-
ers ; others, for their delicate fragrance. The roots of all are acrid,
and emetic. Those of some South American species of Ionidium
furnish a part of the Ipecacuanha of commerce.

758. Ortl. CistaceCC {Rock-Rose Family). Low "shrubby plants or
herbs, with simple and entire leaves (at least the lower opposite).
Calyx of five persistent sepals ; the three inner with a convolute
aestivation ; the two outer small or sometimes* wanting. Corolla of
five, or rarely three, regular petals, convolute in aestivation in the
direction contrary to that of the sepals, often crumpled, usually
ephemeral, sometimes wanting, at least a portion of the flowers.
Stamens few or numerous, distinct, with short innate anthers. Fruit

a one-celled capsule with parietal placenta;, or imperfectly three to
five-celled by dissepiments arising from the middle of the valves
(dehiscence therefore loculicidal), and bearing the placentas at or near
the axis. Seeds few or numerous, mostly orthotropous, with mealy

FIG. 713 The Rock-Rose, Ilelianthemum Canadense. 714. Flower from which the petals
and stamens have fallen. 715 Magnified cross-section of the ovary ; with a single stamen,
showing its hypogynous insertion 716 Cross-section of a capsule, loculicidally dehiscent ;
the seeds therefore borne on the middle of each valve. 717. An ovule. 718 Plan of the
flower. 719. Section of a seed, showing the curved embryo.

394 ILLUSTRATIONS OK THE NATURAL ORDERS.

albumen. Embryo curved, or variously coiled or bent. — Ex. Cistus,
Helianthemum : a small family ; the flowers often showy. No im-
portant properties. Several exude a balsamic resin, such as Lada-
num from a Cistus of the Levant.

759. Onl. Dl'OSCracetC (Simdew Family). Small herbs, growing in
swamps, usually covered with gland-bearing hairs ; with the leaves
rolled up from the apex to the base in vernation (circinnate) : stip-
ules none, except a fringe of hairs or bristles at the base of the
petioles. Calyx of five equal sepals, persistent. Corolla of five
regular petals, Avithering and persistent, convolute in aestivation.
Stamens as many as the petals and alternate with them, or some-
times two or three times as many, distinct, Avithering ; anthers ex-
trorse. Styles three' to five, distinct or nearly so, and each two-
parted (so as to be taken for ten styles, Fig. 510), and these divis-
ions sometimes two-lobed or many-cleft at the apex. Fruit a one-
celled capsule, opening loculicidally by three to five valves, with
three to five parietal placentas ; in Dionaea membranaceous, burst-
ing irregularly, and with a thick placenta at the base. Seeds usu-
ally numerous. Embryo small, at the base of cartilaginous or fleshy
albumen. — Ex. Drosera, the Sundew ; and Dionaea (Venus's Fly-
trap, Fig. 297, 298), so remarkable for its sensitive leaves, which
suddenly close when touched. The styles of the latter are all united
into one.

7 GO. Oft]. Pamassiaccx is for the present made for the genus Par-
nassia, which was formerly appended to Droseraceae (for no good
reason), and has since been placed by some next to Hypericaceae, by
others referred to Saxifragaceae. It is remarkable for having the
four or five stigmas situated directly over the parietal placentae (p.
294, note), and for the curious appendages resembling sterile sta-
mens before each petal (Fig. 380, 381).

761. Ord. HypcricacCflB (St. Johnsicort Family). Shrubs or herbs,
with a resinous or limpid juice, and opposite entire leaves, destitute
of stipules, and punctate with pellucid or blackish dots. Flowers
regular. Calyx of four or five persistent sepals, the two exterior
often smaller. Petals four or five, convolute in aestivation, often
beset with black dots. Stamens commonly polyadelphous and numer-
ous. Ovary one-celled with parietal placentae, or 4-5-celled (Fig.
375, 497, 498, 508, 509). Capsule with septicidal dehiscence (Fig.
582), many-seeded. — Ex. Hypericum (St. Johnswort) is the type
of this small family. Embryo straight ; albumen little or none.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

395

The plants yield a resinous acrid juice, and a bitter, balsamic ex-
tractive matter.

762. Ord. Elalinaccffi (Waterwort Family). Small annual weeds
with membranaceous stipules between the opposite leaves, and mi-
nute axillary flowers. Sepals and petals three to five. Stamens as
many or twice as many as the petals, distinct. Capsule 2 - 5-celled,
septicidal or septifragal ; the numerous seeds attached to a persist-
ent central axis. Albumen none. - — Ex. Elatine is the type of this
order, containing a few insignificant weeds.

7G3. Ol'd. Cai'J'OphyllaceEB (Pink Family). Herbs, with opposite
entire leaves ; the stems tumid at the nodes. Flowers regular.
Calyx of four or five sepals. Corolla of four or five petals, or
sometimes wanting. Stamens as many, or commonly twice as many,
as the petals, sometimes reduced to two or three. Styles two to
five, stigmatose clown the inside. Ovary mostly one-celled, with a
central or basilar placenta, forming a pod in fruit. Embryo periph-
eric, curved or coiled around the outside of mealy albumen (Fig.
G20, 621, 726). — There are five principal suborders, viz. : —

764. Sllbord. Silcnece (Pink Family proper) ; in which the sepals
are united into a tube, and the petals (mostly convolute in aestiva-
tion) and stamens are inserted on the stipe of the ovary, the former
with long claws (Fig. 432, 449), and there are no stipules. — Ex.
Silene, Dianthus (Pink, Carnation).

765. Subord. Alsilieoe (Chickweed Family) j in which there are no

FIG. 720 Hypericum perforatum (St Johnswort). 721. Its tricarpellary pistil. 722.
Crpss-sectiou of tUe capsule 723 Verti :al section ol a seed and its embr> o.

396

ILLUSTRATIONS OF THE NATURAL ORDERS.

stipules, the ovary is sessile, the sepals and petals (imbricated in
aestivation) are nearly or quite distinct; the petals destitute of claws;
and the stamens are inserted into the margin of a small hypogynous
disk, which, however, occasionally coheres with the base of the calyx,
and becomes perigynous. — Ex. Slellaria, Arenaria, &c. (Chick-
weeds). Some are
ornamental ; others,
such as the common
Chickweed, are in-
significant weeds.

766. Subord. Ille-
ccbreac (Knotwort

Family) ; differing
from the last main-
ly in having sea-
rious stipules ; the
sepals often united
below ; the petals
often Avanting or ru-
dimentary ; the sta-
mens manifestly pe-
rigynous ; and the
fruit more commonly
a one-seeded utricle — Ex. Paronychia and Anychia. Spergula has
conspicuous petals, and many-seeded capsules ; and so differs from
Alsineae only in its stipules. Insignificant weeds.

767. Subord. SclcrantheEB {Knawel Family) is like the last, only
there are no stipules. — Ex. Scleranthus.

768. Sllbord. MollUgincSC {Carpet-weed Family) is apetalous with-
out stipules, and has the stamens alternate with the sepals when of
the same number ; thus effecting a transition to

769. Ord. PortulacaccCC {Purslane Family). Succulent or fleshy
herbs, with entire exstipulate leaves and usually ephemeral flowers.
Calyx mostly of two or three sepals, sometimes cohering with the
base of the ovary. Petals five, or rarely more numerous, sometimes
none. Stamens variable in number, but when equal to the petals
situated opposite them. Styles two to eight, united below. Capsule

FIG. 724. Moehringia lateriflora. 725 A magnified flower. 726. Magnified section of a
»eed, showing the embryo coiled into a ring around the albumen. 727. Vertical section ot a
pistil of Spergularia.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

397

with few or numerous seeds, attached to a central basilar placenta,
often by slender funiculi. Seed and embryo as in Caryophyllaceae.
— Ex. Portulaca (Purslane, Fig. 389, 588) Claytonia. Chiefly
natives of dry places in the warmer parts of the world ; except
Claytonia. Insipid or slightly bitter : several are pot-herbs, as the
Purslane. Some are ornamental. The farinaceous root of Lewisia

7.8

730 732 733 731 733 73S

rediviva, a native of the dry interior plains of Oregon, is an impor-
tant article of food with the natives.

770. Ord. Mcsembryanthcmacea: (Fig-Marigold Family) consists of

succulent plants, with showy flowers opening only under bright sun-
shine, containing an indefinite number of petals and stamens, and a
many-celled and many-seeded capsule : otherwise much as in Caryo-
phyllacese. — Ex. Mesembryanthemum (Fig-Marigold, Ice-plant);
chiefly natives of the Cape of Good Hope, flourishing in the most
arid situations.

771. Ol'd. MalVRCCai (Mallow Family). Herbs, shrubs, or rarely
trees. Leaves alternate, palmately veined, with stipules. Flowers
regular, often with an involucel, forming a double calyx. Calyx
mostly of five sepals, more or less united at the base, valvate in

FIG. 728 Flower of the Turslane ; the calyx cut away at the point where it adheres to the
ovary, and laid open 720. A capsule (pyxis) of the same, transversely dehiscent 730. Clay-
tonia Virginica (Spring-Beauty) 731 Diagram of the flower 732. Young fruit and the per-
sistent two-leaved calyx. 733. Section of the dehiscing capsule. 734. A sued. 735 The
same, vertically divided. 736. The embr} o, detached.

34

398

ILLUSTRATIONS OF THE NATURAL ORDERS.

aestivation. Petals as many as the sepals, convolute in aestivation,
hypogynous. Stamens indefinite, monadelphous, united with the
claws of the petals : anthers reniform, confluently one-celled. Pollen
hispid (Fig. 483). Ovary several-celled, with the placentas in the
axis ; or ovaries several. Fruit capsular, or the carpels separate
or separable. Seeds with a little mucilaginous or fleshy albumen.
Embryo large, with foliaceous cotyledons, variously incurved or

folded. — Ex. Malva (Mallow), Althaea (Hollyhock), Gossypium
(Cotton), &c. : a rather large and important family, the herbage,
&c. commonly abounding in mucilage, and entirely destitute of un-
wholesome qualities. The unripe fruit of Abelmoschus or Hibiscus
esculentus (Okra) is used in soups. Althaea officinalis is the Marsh
Mallow of Europe, the Guimauve of the French. The tenacious
inner bark of many species is employed for cordage. Cotton is the
hairy covering of the seeds of Gossypium : the long and slender
tubes, or attenuated cells, collapse and twist as the seed ripens,
which renders the substance capable of being spun. Cotton-seed
yields a good fixed oil. Some species are cultivated for ornament.
772. Ol'd. Byttncriacca! is distinguished from the foregoing by its
usually definite stamens, and the two-celled anthers (the cells par-
allel), with smooth pollen. — A Melochia and a Hermannia are
found in Texas. The rest of the order is tropical or subtropical.
Chocolate is made of the roasted and comminuted seeds of Theo-
broma Cacao (a South American tree), mixed with sugar, arnotto,
vanilla, and other ingredients. The roasted integuments of the seeds,
also, are used as a substitute for coffee.

FIG. 737. The Marsh Mallow (Althrca officinalis). 733. One of the kidney-shaped one-celled
anthers, magnified. 739 The pistils, magnified 740. Capsule of Hibiscus Moscheutos, with
the persistent cal} x and involucel. 741. The same, loculicidully dehiscent.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

399

773. Ord. SterculiacefE, very closely allied to the last two, and con-
sisting of tropical trees, possesses the same mucilaginous properties
(as well as oily seeds), with which hitter and astringent qualities are
often comhined. The seeds of Bombax, the Silk-cotton tree, are
enveloped in a kind of cotton, which belongs to the endocarp and
not to the seed ; and the hairs, being perfectly smooth and even, can-
not be spun. Canoes are made from the trunk of the huge Bombax
Ceiba, in the West Indies. To this order belongs the famous
Baobab, or Monkey-bread, of Senegal (Adansonia digitata), some
trunks of which are from sixty to eighty feet in circumference !
The fruit resembles a gourd, and serves for vessels ; it contains a
subacid and refrigerant, somewhat astringent pulp ; the mucilagi-
nous young leaves are also used for food in time of scarcity ; the
dried leaves (Zafo) are ordinarily mixed with food, and the bark
furnishes a coarse thread, which is made into cordage or woven into
cloth. Cheirostemon platanoides is the remarkable Hand-flower
tree of Mexico. A plant of the family (Fremontia, Torr.) nearly
allied to Cheirostemon has been found in California, by Fremont.

774. Ord. TiliaccEB {Linden Family). Trees or shrubby plants,
with alternate leaves, furnished with deciduous stipules, and small

flowers. Calyx deciduous. Petals sometimes imbricated in asstiva-

FIG. 742. Flowering branch of Tilia Americana the common American Linden ; the flower,
stalk cohering with the bract. 743 One of the clusters of stamens adhering to the petaloid
scale 744 The pistil. 745. Cross-section of the fruit, which has become one-celled by the
obliteration of the partitions, and one-seeded. 748 Vertical section of the seed, magnified, to
show the large embryo with its taper radicle and foliaccous crumpled cotyledons. (A better
section of the seed, cut in the direction across tile cotyledons, u shown in Fijf 699.) 747.
l)iagram of the flower.

400 ILLUSTRATIONS OK THE NATURAL ORDERS.

tion. Stamens indefinite, often in three to five clusters, distinct or
somewhat united, one of each parcel often transformed into a peta-
loid scale (Fig. 383, 743) : anthers two-celled. Styles united into
one. Fruit two to five-celled, or, hy obliteration, one-celled when
ripe. Tn other respects nearly as in Malvaceae. — Tilia, the Linden,
or Lime-Tree, represents the order in northern temperate regions ;
the other genera are tropical. All are mucilaginous, with a tough
fibrous inner bark. From this bast or bass of the Linden, the Rus-
sian mats, &c. are made, whence the name of Basswood. Gunny-
bags and fishing-nets are made in India from the bark of Corchorus
c:ipsularis ; the fibre of which, called Jute, is spun and woven. The
light wood of the Linden is excellent for wainscoting and carv-
ing : its charcoal is used for the manufacture of gunpowder. It is
said that a little sugar may be obtained from the sap : and the honey
made from the odorous flowers is thought to be the finest in the
world. The acid berries of Grewia sapida arc employed in the
East in the manufacture of sherbet.

775. Ol'il. Diptci'OCarpetC, allied in some respects to Tiliaceae, con-
sists of a few tropical Indian trees, with a resinous or balsamic juice.
Dryobalanops aromatica, a large tree of Sumatra and Borneo, yields
in great abundance camphor oil and solid camphor : both are found
deposited in cavities of the trunk. It is more solid than common
camphor, and is not volatile at ordinary temperatures. It bears a
high price, and is seldom found in Europe or this country, but is
chiefly carried to China and Japan. Shorea robusta yields the
Dammer-pitch. Vateria Indica exudes a kind of copal, the Gum
Animi of commerce ; and a somewhat aromatic fatty matter, called
Piney Tallow, is derived from the seeds.

776. Ortl. Gllttifcrxc, or ClusiaccJC, consists of tropical trees, with a
yellow resinous juice, opposite and coriaceous entire leaves, and
large flowers with many stamens, little distinction between the
sepals and petals, no styles, an indehiscent fruit, and seeds with a
peculiar undivided fleshy embryo. It has been asspciated with Ily-
pericacea;, but is more related to the ensuing families. The resin-
ous juice is acrid and drastic ; that of a Ceylonese tree of the order
yields Gamboge. It is remarkable that such an order should pro-
duce one of the most esteemed fruits, viz. the Mangosteen, yielded by
Garcinia Mangostana of Malacca, and also the Mammee-apple, &c.

777. Ord. CamelliaccCC {Camellia or Tea Family). Trees or shrubs,
with a watery juice, alternate simple leaves without stipules, and

EXOGENOUS OR DICOTYLEDONOUS PLANTS. 401

large and showy flowers. Calyx of three to seven coriaceous and
concave imbricated sepals. Petals five or more, imbricated in aesti-
vation. Stamens hypogynous, indefinite, monadelphous or polyadel-
phous at the base. Capsule dehiscent, several-celled, usually with a
central column. Seeds few in each cell, large, often winged, with
or without albumen. — The Camellia and the closely related Tea-
plant form the type of this family, to which belong our Gordonia
and Stuartia. The leaves of Tea contain a peculiar extractive mat-
ter, and an ethereal oil ; its moderately stimulant properties are
said to become narcotic in very hot cl mates.

778. Ord. TcMStramiacCOC, chiefly tropical, with which the last has
been confounded, by its aspect, its commonly polygamous flowers,
and more or less gamopetalous corolla, &c, appears on the whole
to be more allied to the Ebenacerc and Symplocineai.

770. Ol'd. AuratUiacCEB {Orange Family). Trees or shrubs, with
alternate leaves (compound, or with jointed petioles), destitute of
stipules, dotted with pellucid glands full of volatile oil. Flowers
fragrant. Calyx short, urceolate or campanulate. Petals three to
five. Stamens inserted in a single row upon a hypogynous disk
(Fig. 434), often somewhat monadelphous or polyadelphous. Style
cylindrical. Fruit a many-celled berry, with a leathery rind, filled
with pulp. Seeds without albumen. — Ex. Citrus, the Orange and
Lemon. Nearly all natives of tropical Asia ; now dispersed through-
out the warmer regions of the world, and cultivated for their beauty
and fragrance, and for their grateful fruit. The acid of the Lemon,
Lime, &c. is the citric and the malic. The rind abounds in a vola-
tile oil (such as the Oil of Bergamot from C. Limetta),and an aro-
matic, bitter principle.

780. Oi'd. McliaCCffi. Trees or shrubs, with alternate, usually com-
pound leaves, destitute of stipules. Calyx of three to five sepals.
Petals three to five. Stamens twice as many as the petals, mona-
delphous, inserted with the petals on the outside of an hypogynous
disk ; the anthers included in the tube of filaments. Ovary several-
celled, with one or two ovules in each cell : styles and stigmas united
into one. Fruit a drupe, berry, or capsule ; the cells one-seeded.
Seeds without albumen, wingless. — Ex. Melia Azedarach (Pride of
India), naturalized, as an ornamental tree, in the Southern States.
An acrid and bitter principle pervades this tropical order.

781. Ord. Ct'drclacCiB {Mahogany Family). Trees (tropical or
Australian), with hard and durable, usually fragrant and beautiful

34*

402

ILLUSTRATIONS OF THE NATURAL ORDKRS.

"wood ; differing botanically from Meliacea? chiefly by their capsular
fruit, with several winged seeds in each cell. — Ex. The Mahogany
(Swietenia Mahagoni) of tropical America, reaching to East Flor-
ida. Bark, &c. bitter, astringent, tonic, often aromatic and febrifugal.
782. Ol'd. LiliaCCtE (Flax Family). Herbs, with entire and sessile
leaves, either alternate, opposite, or verticillate, and no stipules, ex-
cept minute glands. Flowers regular and symmetrical. Calyx of
three or five persistent sepals, strongly imbricated. Petals as many
as the sepals, convolute in aestivation. Stamens as many as the
petals, and usually with as many intermediate teeth representing an
abortive series (Fig. 423), all united at the base into a ring, hypogy-

nous. Ovary with as many styles and cells as there are sepals,
each cell with two suspended ovules ; the cells in the capsule each
more or less divided into two, by a false par-
tition which grows from the back (Fig. 7.30) ;
the spurious cells
one-seeded. Em-
bryo straight :
cotyledons flat,
fleshy and oily,
730 surrounded by a

thin albumen. — Ex. Linum, the Flax. The tough woody fibre of
the bark {flax) is of the highest importance : the seeds yield a
copious mucilage, and the fixed oil expressed from them is applied
to various uses in the arts. The general plan of the flower is the
same in the succeeding orders.

FIG. 748 Flowers of the common Flax. 749 Vertical section of a flower. 750. Diagram
of the same, in a transverse section. 751. Its 10-celled capsule transversely divided 752.
Similar section of the incompletely 10-celled capsule of Linum pereune.

EXOGENOUS OR DICOTYLEDONOUS TLANTS.

403

783. Ord. GcraniacCfE {Cranesbill Family). Herbs or shrubby
plants, commonly strong-scented ; with palmately veined and usually
lobed leaves, mostly with stipules ; the lower opposite. Flowers
regular. — Calyx of five persistent sepals, imbricated in aestivation.
Petals five, with claws, mostly convolute in aestivation. Stamens 10,
the five exterior hypogynous, occasionally sterile ; the filaments all
broad and often united at the base ; five glands within and alternate
with the petals. Ovary of five two-ovuled carpels, attached to the
base of an elongated axis (gynobase, Fig. 430, 431) to which the
styles cohere : in fruit the distinct one-seeded carpels separate from
the axis, by the twisting or curling back of the persistent indurated

styles from the base upwards. Seeds with no albumen : cotyledons
convolute and plaited together, bent on the short radicle. For the
plan of the blossom see p. 2G4, and Fig. 421. Our cultivated
Geraniums, so called, from the Cape of Good Hope, are species of
Pelargonium. The roots are simply and strongly astringent. The
foliage abounds with resinous matter and an ethereal oil, on which
the aroma depends.

784. Ord. BalsaminaCCSC (Balsam Family). Annual herbs, with
succulent stems filled with a watery juice. Leaves simple, without
stipules. Flowers irregular, and one of the colored sepals spurred
or saccate. Stamens five, cohering by an internal appendage.

PIG. 753 Radical leaf of Geranium marulatum (Cranesbill). 754 A flowering branch.
755 A flower with the calyx and corolla removed showing the stamens, &c 75G. The pistil
iu fruit; the indurated styles separating below from the prolonged axis, and curving back
elastically, carrying with them the membranous carpels. 757. A magnified seed. 758. A
cross-section of the same, showing the folded pud convolute cotyledons.

404 ILLUSTRATIONS OF THE NATURAL ORDERS.

Compound ovary five-celled; stigmas sessile. Capsule bursting
clastically by five valves. Seeds several, without albumen, and with
a thick straight embryo. — Ex. Impatiens, the Balaam, or Touch-
me-not. Remarkable for the elastic force with which the capsule
bursts in pieces, and expels the seeds. Somewhat differently irreg-
ular blossoms are presented by the

785. Ord. TropCDOlacCie {Indian- Cress or Nasturtium Family).
Straggling or twining herbs, with a pungent watery juice, and peltate
or palmate leaves. Flowers irregular. Calyx of five colored and
united sepals, the lower one spurred. Petals five ; the two upper
arising from the throat of the calyx, remote from the three lower,
which are stalked. Stamens eight, unequal, distinct. Ovary three-
lobed, composed of three united carpels ; which separate from the
common axis Avhen ripe, are indehiscent, and one-seeded. Seed
filling the cell, without albumen: cotyledons very large and thick. —
Ex. Tropceolum, the Garden Nasturtium, from South America,
where there are a few other species, one of which bears edible tubers.
They possess the same acrid principle and antiscorbutic properties
as the Cruciferae. The unripe fruit of Tropseolum majus is pickled,
and used as a substitute for capers.

786. Ord. LimnanthaCCDE differs from the last only in its regular and
symmetrical blossoms, and the erect instead of suspended seeds ; the
calyx valvate in aestivation. — Ex. Limnanthes of California (some-
times cultivated as an ornamental annual), and Flocrkea of the
Northern United States.

787. Ord. OxalidaCCBC ( Wood-Sorrel Family). Low herbs, with an
acid juice, and alternate compound leaves ; the leaflets usually ob-
cordate. Flowers regular, of the same general structure as in Li-
naceae, &c., except the gynaecium, which in fruit forms a membra-
naceous five-lobed and five-celled, several-seeded capsule. Seeds
with a fleshy outer coat, which bursts elastically when ripe, with a
large and straight embryo in thin albumen. — Ex. Oxalis, the
Wood-Sorrel. The herbage is sour, as the name, denotes, and con-
tains oxalic acid. The foliage is remarkably sensitive in some spe-
cies. The tubers of some South Amei-ican species, filled with starch,
have been substituted for potatoes.

788. Ord. Zygophyllacea; differs from the last in the opposite,
mostly abruptly pinnate leaves, distinct stamens (the filaments com-
monly furnished with an internal scale, Fig. 379), and the styles
united into one. — Ex. Tribulus and Kallstrcemia (introduced into

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

405

the Southern States) are exalbuminous ; the latter is 10-eoecous,
just as Linum is, by a false partition. Guaiacum, Larrea (Creo-
sote-plant of New Mexico and Texas), and the rest of the family,
have a corneous albumen. The wood of Guaiacum (Lignum-vitce)
is extremely hard and heavy, and yields a gum-resinous, bitter, and
acrid principle (Gum Guaiacum), well known in medicine.

789. Ol'd. Simarilbaccae (Quassia Family), of tropical shrubs or
trees, resembles the last in generally having a peculiar scale to the
filaments. It is, however, more nearly related to the next order,
but its apocarpous ovaries are one-ovuled, and the (mostly com-
pound) leaves are dotless. The wood, &c. is intensely bitter : that
of Quassia amara is used as a stomachic tonic. The seed of Cedron
(Simaba Cedron) is the famous antidote for the bites of venomous
snakes in Central America.

790. Ord. Rlltacca: (Rue Family). Herbs, shrubs, or trees ; the
leaves punctate with pellucid dots, and without stipules. Calyx of
four or five sepals. Petals four or five, or rarely none. Stamens

7St 762 763 . 766

as many or twice (rarely three times) as many as the petals, insert-

FIG. 759. A flowering branch of Zanthoxylum Americanum (the Northern Prickly Ash).
760 A piece of a leaf, to' show the pellucid dots. 761 Staminate flower. 762. A pistillate
fower, the sepals spread open. 763. Two of the pistils ; one of them divided vertically to show
the ovules. 764. A branch in fruit. 765. One of the dehiscent pods, and the seed. 766 Ver.
tical section of an unripe pod and seed ; the latter pendent from a descending funiculus, show-
ing a slender embryo in copious albumen.

406 ILLUSTRATIONS OF THE NATURAL ORDKRS.

eel on the outside of .1 hypogynous disk. Ovary three- to five-lobed,
three- to five-celled, with the styles united, or distinct only at the
base, or the ovaries nearly separate, during ripening usually sepa-
rating into its component carpels, which are dehiscent by one or
both sutures. Seeds few or single, mostly with albumen ; and a
curved embryo. — Ex. Ruta (the Rue), Dictamnus (Fraxinella), of
Europe. Dlosma and its allies, of the Cape of Good Hope, New
Holland, &c, form a group, or suborder (Diosmeje) from which the
Zantiioxyle;e (or Prickly-Ash Family) differs only in being gen-
erally dioecious ; but have no claim to be ranked as a distinct order.
Strong-scented, bitter-aromatic, often very pungent, from an acrid
volatile oil (as Rue and Zanthoxylum) ; also bitter. Some contain
a bitter alkaloid, and are febrifugal. The most important is the
Galipea, which furnishes the Angostura bark.

791. Ord Anacai'diacetE {Cashew Family). Trees or shrubs, with
a resinous or milky, often acrid juice, which turns blackish in dry-
ing ; the leaves alternate, without stipules, and not dotted. Flowers
small, often polygamous or dioecious. Calyx of three to five sepals,
united at the base. Petals, and usually the stamens, as many as the
sepals, inserted into the base of the calyx or into an hypogynous disk.
Ovary one-celled, but with three styles or stigmas, and a single ovule.
Fruit a berry or drupe. Seed without albumen. Embryo curved
or bent. — Ex. Rhus, Anacai'dium (the Cashew), Pistacia. Chiefly
tropical ; except Rhus. The acrid resinous juice is used in var-
nishes ; but it often contains a caustic poison. Even the exhalations
from Rhus Toxicodendron (Poison Oak, Poison Ivy), and R. vene-
nata (Poison Sumach, Poison Elder), as is well known, severely
alfect many persons, producing a kind of erysipelas. Their juice is
a good indelible ink for marking linen. But the common Sumachs
(R. typhina and R. glabra) are innocuous ; their bark or leaves are
used for tanning, and their sour berries (which contain bimalate of
lime) for acidulated drinks. The oily seeds of Pistacia vera (the
Pistachio-nut) are edible ; and the drupe of Mangifera Indica
(Mango) is one of the most grateful of tropical fruits. The kernel
of the Cashew-nut (Anacardium occidentale) is eatable ; and so is
the enlarged and fleshy peduncle on which the nut rests : but the
coats of the latter are filled with a caustic oil, which blisters the
skin ; while from the bark of the tree a bland gum exudes.

792. Oi'J. B'Jrscracea;, including a great part of what were formerly
called Terebinthaeea?, consists of tropical trees, with a copious resin-

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

407

ous juice, compound leaves usually marked with pellucid dots, and
small flowers ; with valvate petals, a two- to five-celled ovary, and
drupaceous fruit. Their balsamic juice, which flows when the trunk
is wounded, usually hardens into a resin. The Olibanum, used as a
fragrant incense, the Balm of Gilead, Balsam of Mecca, Myrrh, and
the Bdellium, are derived from Arabian species of the order ; the East
Indian Gum Elemi, from Canarium commune ; Balsam of Acouchi,
and similar substances, from various American trees of this family.

793. Ord. ImyridaCCffi consists of a few West Indian plants, inter-
mediate as it were between Burseraceaa and Leguminosns, and dis-
tinguished from the former chiefly by their simple and solitary ovary.
— Very probably this and the two last are to be recoinbined.

794. Ord. YitacCfC ( Vine Family). Shrubby plants, climbing by
tendrils, with simple or compound leaves, the upper alternate.

FIG. 767. A branch of the Grapc-Yinc. 768. A flower ; the petals separating from the
base, and falling off together without expanding. 7G9. A flower from which the petals havo
fallen; the lobes of the disk Been alternate with the stamens. 770 Vertical section through,
the ovary and the base of the flower : a, cnlj x, the limb of which is a mere rim : b. petal,
having the stamen, c, directly before it ; and the lobes of the disk are shown between this aud
the ovary. 771 A seed. 772 Section of the seed, showing the thick crustaceous testa, and
the albumen, at the base of which is the minute embryo. 772'. A horizontal plan of the flower.

408 ILLUSTRATIONS OF THE NATURAL ORDKRS.

Flowers small, often polygamous or dioecious. Calyx very small,
filled with a disk ; its limb short or obsolete. Petals 4 or a, valvate
in aestivation, sometimes cohering by their tips, and caducous. Sta-
mens as many as the petals and opposite them ! Ovary two-celled,
with two erect ovules in each cell. Fruit a berry. Seeds with a
bony testa, and a small embryo in hard albumen. — Ex. Vitis (the
Vine), Ampelopsis (the Virginia Creeper). The fruit of the Vine
is the only important product of the order. The acid of the grape,
which also pervades the young shoots and leaves, is chiefly the tar-
taric. Grape-sugar is very distinct from cane-sugar, and the only
kind that can long exist in connection with acids.

795. Ord. RhamiiacCJE {Buckthorn Family). Shrubs or trees, often
with spinose branches ; the leaves mostly alternate, simple. Flowers
small. Calyx of four or five sepals, united at the base, valvate in
aestivation. Petals four or five, cucullate or convolute, inserted on
the throat of the calyx, sometimes wanting. Stamens as many as
the petals, inserted with and opposite them ! Ovary sometimes
coherent with the tube of the calyx, and more or less immersed in a
fleshy disk, with a single erect ovule in each cell (Fig. 40.3, 43G).
Seeds not arilled. Fmbryo straight, large, in sparing albumen. —
Ex. Rhamnus (Buckthorn) is the type of the order. The berries
of most species are somewhat nauseous ; but those of Zizyphus are
edible. Jujube jyaste is prepared from those of Z. Jujuba and Z.
A^ulgaris of Asia. Syrup of Buckthorn and the pigment called Sop-
green are prepared from the fruit of Rhamnus catharticus. The
herbage and bark in this order are more or less astringent and
bitter. An infusion of the leaves of Ceanothus Americanus (thence
called New Jersey Tea) has been used as a substitute for tea, and a
very poor one it is.

796. Ord. Cclastracece {Spindle-tree Family). Shrubs or trees,
with alternate or opposite simple leaves. Calyx of four or five
sepals, imbricated in aestivation. Petals as many as the sepals, in-
serted under the fiat expanded disk which closely surrounds the
ovary, imbricated in aestivation. Stamens as many as the petals,
and alternate with them, inserted on the margin or upper surface
of the disk. Ovary free from the calyx. Fruit a capsule or berry,
with one or few seeds in each cell. Seeds usually arilled, albumi-
nous, with a large and straight embryo. — Ex. Celastrus, Fuonymus
(Burning Bush, Spindle-tree, Strawberry-tree) ; all somewhat bitter
and acrid ; but of little economical importance. The red or crim-

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

409

son capsules and bright scarlet arils of several species present a
striking appearance when the fruit is ripe.

797. Ol'd. Malpig!liace?e is a large tropical family (with one or two
representatives in Texas), of trees, shrubs, and twining plants, with
opposite entire leaves, unguiculate petals, and solitary seeds with a
curved embryo ; differing from the next in the want of a disk, the
more symmetrical flowers, &c.

798. Orel. SnpilldaceSP {Soapberry Family). Trees, shrubs, or climb-
ers with tendrils, rarely herbs, with simple or compound leaves, and
mostly unsymmetrical or irregular flowers ; the sepals and petals
imbricated in aestivation. Stamens 5 to 10, inserted on a fleshy
perigynous or hypogynous disk. Ovary 2-3-celled, 2-3-lobed, with
one or two (in Staphylea several) ovules in each cell ; the embryo
(except in Staphylea) curved or convolute and without albumen. —
Includes a variety of forms, the greater part of which may be ranged
under the following suborders, which have been taken for orders.

799. Sllbord. StapllYlcaceSB {Bladdernut Family) has opposite com-
pound leaves with stipules and stipels, regular and perfect pentan-

FIG. 773. Flowering branch of .Esculus Pavia (Red Buckeye). 774 A flower. 775. Flower
■with the calyx and two of the petals removed. 776 A ground-plan of the flower, showing
that its parts are unsymmetrical 777. Vertical section of an ovary, showing two of the cells
with a pair of ovules in each, one ascending one descending 778. Cross section of an ovary.
779. Cross-section of the immature fruit ; only one fertile seed j the others abortive. 780
The dehiscent fruit-

85

410

ILLUSTRATIONS OF THE NATURAL ORDERS.

drous floivers, three partly united pistils with several ovules in each,
and large bony seeds, with a straight embryo in scanty albumen. - —
Ex. Stapltylea.

800. Sllboi'll. SapindCcB ( Soapberry Family proper) has alternate, or
in the Horsechestnut tribe opposite leaves, without stipules, more or
less unsymmetrical or irregular and polygamous flowers, exalbu-
minous seeds, and a curved embryo with thickened cotyledons. —
Mostly tropical, except the Horsechestnut and Buckeyes (iEsculus),
which have been deemed a separate family (Hippocastanece). Their
very large and fleshy embryo has the cotyledons more or less con-
solidated (Fig. 629, G30). The seeds of the Horsechestnut are nu-
tritious, but contain an intensely bitter principle which is more or
less noxious. Those of J&. Pavia are used to stupefy fish. The
root, according to Elliott, is employed as a substitute for soap. The
fruit of Sapindus is used for the same purpose, whence the name of
Soapberry.

801. Sllbord. AccrinCfE {Maple Family) has opposite (simple or
compound) leaves without stipules, a 2-lobed and 2-winged fruit

FIG. 781. A branch of Acer dasycarpum (the White Soft Maple) with staminate Dowers.
782 A separate, enlarged, staminate flower. 783. Branch with pistillate flowers. 781 A
separate fertile flower. 785. The same, enlarged, with the calyx cut away 78G. A cluster
showing the fruiting ovaries expanding into wings (reduced in size). 787. Ripe fruit ; one of
the samaras cut open to show the seed. 788 A leaf.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

411

forming two samaras, and an embryo with long and thin, variously
curved or coiled cotyledons (Fig. 103-105); otherwise nearly as
in the true Sapindaceae. — Ex. Acer, the Maple ; useful timber-trees
of northern temperate regions. Sugar is yielded by the vernal sap
of Acer saccharinum, and in less quantity by all the species.

802. Ord. PolygalaceSC. Herbs or shrubby plants, with simple
entire leaves, destitute of stipules. Flowers perfect, unsymmetrical,
and irregular, somewhat papilionaceous in appearance, but of wide-
ly different structure. Calyx of five irregular sepals ; the odd one
superior, the two inner (wings) larger, and usually petaloid. Petals
usually three, inserted on the receptacle, more or less united ; the
anterior (keel) larger than the rest. Stamens six to eight, combined
in a tube, which is split on the upper side, and united below with
the claws of the petals : anthers innate, mostly one-celled, opening
by a pore at the apex. Ovary compound, two-celled, with a single
suspended ovule in each cell : style curved and often hooded.

Capsule flattened. Seeds usually with a cai'uncle. Embryo straight,
large, in fleshy, thin albumen. — Ex. Polygala is the principal genus
of the order. The plants yield a bitter principle with some acrid

FIG 789. Polrgala paucifolia. 790. A flower, enlarged. 791 The calyx displayed. 792
Tim corolla and sramineal tube laid open. 793 The pistil and the free portion of the stamens.
791 Vertical section of the ovary. 795 Vertical section of the seed, showing the large embryo
and scanty albumen.

412 ILLUSTRATIONS OK THE NATURAL ORDLKS.

extractive matter. Polygala Senega (Seneca Snakeroot) is the
most important medicinal plant of the family. Other species are
employed medicinally in Brazil, Peru, Nepaul, &c. ; where, like
our own, they are reputed antidotes to the bites of venomous
reptiles.

803. Ol'd. KranieriacCiE (Rhatany Family) consists of the gertus
Krameriu only, which has ordinarily been annexed to the Polyga-
lacese ; but the position of the parts of the flower is more like that
of the Leguminosse, having the odd sepal inferior, a simple unilocu-
lar pistil, and an exalbuminous seed. In fact it is technically distin-
guishable from the latter chiefly by the hypogynous stamens and the
want of stipules. The roots contain a red coloring matter, and are
astringent without bitterness. Rhatany-root, used to adulterate port-
wine, and as an ingredient in tooth-powders, &c, is the produce of
K. triandra of Peru. That of our own Southern species possesses
the same properties.

804. Old. LcgliminosfE (Pulse Family). Herbs, shrubs, or trees,
with alternate and usually compound leaves, furnished with stipules.

FIG 703. A flowering branch of Lathyrus palustris, var. myrtifolius. 707. The corolla
displayed : a, the vexillum or standard ; 6 the aim or wings ; c, the two petals of the carina
or keel 798 The keel-petals in their natural situation. 790. The stamens and pistil, en-
larged j the sheath of filaments partly turned back.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

413

Calyx mostly of five sepals, more or less united ; the odd sepal in-
ferior (Fig. 358). Corolla of five petals, either papilionaceous or
regular. Stamens perigynous, or sometimes hypogynous. Ovary
single and simple. Fruit a legume, various forms of which are
shown in Fig. 580, 581, 800-807. Seeds destitute of albumen, or
with a mere vestige of it. — This immense family is divided into
three principal suborders ; viz. : —

805. Subord. PapilionacCiE {Pulse Family proper), which is charac-
terized by the papilionaceous corolla, — the vexillum always exter-
nal in aestivation (471, Fig. 392), — ten diadelphous (Fig. 4G1),
monadelphous (Fig. 4G2), or rarely distinct, perigynous stamens,
and the radicle bent on the large cotyledons. Leaves (rarely sim-
ple) only once compound ; the leaflets very rarely toothed or lobed.

806. Subord. CtCsalpi'ncfC (to which Cassia, Cercis, and the Honey-
Locust belong) : here the corolla gradually loses its papilionaceous
character, and always has the vexillum, or superior petal, covered
by the lateral ones in aestivation ; the stamens are distinct, and the
embryo straight. The leaves are often bipinnate.

807. Subord. MilUOSetC (a large group, to which the Acacia and the
Sensitive Plant belong) lias a perfectly regular calyx and corolla,
the latter mostly valvate in aestivation and hypogynous, as well as
the stamens, Avhich are sometimes definite, but often very numerous ;
and the embryo is straight. The leaves are frequently tripiimate.

FIG. 800 Open legume of the Pea. 801. Loment of Desmodium. 802. Loment of Mi-
mosa : b, one of its dehiscent joints which has fallen away from the persisting border or frame
(repluni), seen in 803. 804. The jointed indehiscent legume of Sophora. 805 A legume of
Astragalus cut across near the summit, to show how it becomes partly or entirely two-celled
by the introflcxion of the dorsal suture. £06 Similar view of a legume of Phaca, where the
ventral suture is somewhat introflexed 807. A legume of Medicago scutellata, spirally coiled
into a globular figure.

35*

414 ILLUSTRATIONS OF THE NATURAL ORDERS.

808. Papilionacea; are found in every part of the world : Cresal-
pinea? and Mimosea? are confined to the tropical and warmer tem-
perate regions. — A full account of the useful plants and products
of this large order would require a separate volume. Many, such
as Clover, Lucerne (Medicago sativa), &c, are extensively culti-
vated for fodder ; Peas and Beans, for puke. The roots of the
Licorice (Glycirrhiza glabra of Southern Europe) abound in a
sweet mucilaginous juice, from which the pectoral extract of this
name is prepared. The sweet pulp of the pods of Ceratonia Siliqua
(Carob-tree of the South of Europe, &c), like that of the Honey-
Locust (Gleditschia), &c, is edible. The laxative pulp of Cathar-
tocarpus Fistula, and of the Tamarind, is well known ; the latter is
acidulated with malic, and a little tartaric and citric acid. — A pecu-
liar volatile principle (called Coumarin) gives its vanilla-like fra-
grance to the well-known Tonka-bean, and to the Melilotus, or Sweet
Clover. The flowers and seeds of the latter and of Trigonella
crcrulea give the peculiar odor to Scheipzeiger cheese. — Astringents
and tonics are also yielded by this order : such as the African Ptero-
carpus erinaceus, the hardened red juice of which is Gum Kino ;
that of P. Draco, of Carthagena, &c, is Dragons Blood. The bark
of most Acacias and Mimosas contains a veiy large quantity of tan-
nin, and is likely to prove of great importance in tanning. The
valuable astringent called Catechu is obtained by boiling and evap-
orating the heart-wood of the Indian Acacia Catechu. — Legumi-
nosre yield the most important coloring matters : such as the Brazil-
wood, the Logwood of Campeachy (the peculiar coloring principle
of which is called Hcematin), and the Red Sandal-wood of Ceylon.
Indigo is prepared from the fermented juice of the Indigofera tinc-
toria (a native of India), and other species of the genus. ■ This
substance is highly azotized, and is a violent poison. — To the same
order we arc indebted for valuable resins and baLams ; such as the
Mexican Copal, Balsam of Copaiva of the West Indies, Para, and
Brazil, the bitter and fragrant Balsam of Peru, and the sweet, fra-
grant, and stimulant Balsam of Tolu. — It al.-o furnishes the mo4
useful gums ; of which we need only mention Gum Tragacanth,
derived from Astragalus verus of Persia, &c. ; and Gum Arabic,
the produce of certain African species of Acacia. The best is
said to be obtained from Acacia vera, while Gum Senegal is yielded
by A. Verek, and some other species. Algarobia dulcis, the Mes-
quite of Texas and Mexico, yields a similar gum. The Senna of

EXOGENOUS OR DICOTYLEDONOUS PLANTS. 415

commerce consists of the leaves of several species of Cassia, of
Egypt and Arabia. C. Marilandiea of this country is a succedane-
um for the officinal article. — More acrid, or even poisonous prop-
erties, are often met with in the order. The roots of Baptisia
tinctoria (called Wild Indigo, because it is said to yield a little of
that substance), of the Broom, and of the Dyers' Weed (Genista
tinctoria, used for dyeing yellow), possess such qualities ; while the
seeds of Laburnum, &c. are even narcotico-acrid poisons. The
branches and leaves of Tephrosia, and the bark of the root of
Piscidia Erythrina (Jamaica Dogwood, which is also found in South-
ern Florida), are commonly used in the West Indies for stupefying
fish. Cowitch is the stinging hairs of the pods of species of Mu-
euna. — Among the numerous valuable timber-trees, our own Locust
(Robinia Pseudacacia) must be mentioned ; and also the Rosewood
of commerce, the produce of some Brazilian Ca>alpinieo3, Few
orders furnish so many plants cultivated for ornament.

809. Ord. Rosacea {Rose Family). Trees, shrubs, or herbs, with
alternate leaves, usually furnished with stipules. Flowers regular.
— Calyx of five (rarely three or four) more or less united sepals,
and often with as many bracts. Petals as many as the sepals-
(rarely none), mostly imbricated in aestivation, perigynous. Sta-
mens indefinite, or sometimes few, distinct. Ovaries with solitary
or few ovules : styles often lateral. Albumen none. Embryo
straight, with broad and fiat or plano-convex cotyledons (Fig. 108-
111). — This important order is divided into four suborders; viz.: —

810. Subord. ClirysobalailCiE {Cocoa-plum Family). This is now
generally taken as an independent order, intermediate between
Leguminosa; and Rosacea?. Ovary solitary, free from the calyx, or
else cohering with it at the base on one side only, containing two
erect ovules : style arising from the apparent base. Fruit a drupe.
Trees or shrubs. — Ex. Chrysobalanus ; some species of which pro-
duce an edible fruit.

811. Subord. AmygdalcCE {Almond or Plum Family). Ovary soli-
tary, free from the deciduous calyx, with two suspended ovules, and
a terminal style. Fruit a drupe (Fig. 5G2). Trees or shrubs. —
Ex. Amygdalus (the Almond, Peach), Prunus (the Plum), &c.

812. Subord. Rosacea proper. Ovaries several, numerous, or rarely
solitary, free from the calyx (which is often bracteolate, as if
double), but sometimes enclosed in its persistent tube, in fruit becom-
ing either follicles or achenia. Styles terminal or lateral. Herbs or

416

ILLUSTRATIONS OF THE NATURAL OKD'.CRS.

shrubs. — The three tribes of this suborder are : — Tribe 1. SPTUEJE,
where the fruit is a follicle. Ex. Spiraea and Gillenia. Tribe 2.
Dryadeje, where the fruits are achenia, or sometimes little drupes,
and when numerous crowded on an enlarged torus (Fig. 558, 559,
564, 565). Ex. Dryas, Agrimonia, Potentilla, Fragaria (Strawber-
ry), Rubus (Raspberry and Blackberry). Tribe 3. Roseje, where
numerous achenia cover the hollow torus which lines the urn-shaped
calyx-tube ; and the latter, being contracted at the mouth, and be-
coming fleshy or berry -like, forms a kind of false pericarp ; as in the
Rose (Fig. 429, 808).

813. Sllbord. PomefB {Pear Family). Ovaries two to five, or rare-
ly solitary, cohering with each other and with the thickened and
fleshy or pulpy calyx-tube ; each with one or two (in the Quince
several) ascending seeds. Trees or shrubs. — Ex. Crataegus (the
Thorn), Cydonia (the Quince), Pyrus (the Apple, Pear, &c).

bus 810 809 61

814. This impoi'tant order is diffused through almost every part
of the world; but chiefly abounds in temperate climates, where it
furnishes the most important fruits. It is destitute of unwholesome
qualities, with one or two exceptions, viz. : — The bark, leaves, and
kernel of Amygdaleas contain prussic acid, or something of similar
odor and analogous properties ; as is exemplified by the Cherry-Laurel

FIG. 808. Vertical section of an uncxpanded Rose, showing the attachment of the carpels
to the lining of the calyx-tube and of the stamens and petals to its summit or edge. 809.
Vertical section of the fruit of the Quince, exhibiting the carpels invested by the thickened
calyx which forms the edible part of the fruit ; one of the ovaries hid open to show the seeds.
610. A magnified seed ; the rhaphc and chalaza conspicuous 811 The embryo. 812. Cross-
section of an apple. 813. Flower, &c. of the American Crab-apple (Pyrus coronaria).

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

417

of the Old World, from 'which the poisonous Laurel-water and the
virulent Oil of Laurel are obtained. Our Southern species, Primus
(Laurocerasus) Caroliniana, poisons cattle which eat its foliage.
The root of Gillenia (Bowman's Root, Indian Physic) is emetic in
large doses, in small doses it acts as a tonic. The bark and root in
all are astringent. The bark of Amygdaleae also exudes gum.
That of the Wild Black Cherry is febrifugal ; and the timber is
useful in cabinet-work. Sweet and bitter almonds are the seeds of
varieties of Amygdalus communis: the. oil of the former resembles
olive-oil ; that of the latter is poisonous. Of the Peach, Apricot,
Nectarine, Plum, and Cherry, it is unnecessary to speak. The
strawberry, raspberry, and blackberry are the principal fruits of the
proper Rosacea?. The leaves of Rosa centifolia are more commonly
distilled for Rose-water : and Attar of Roses is obtained from R.
Damascena, &c. — Pomaceous fruits, such as the apple, pear, quince,
services, medlar, &c., yield to none in importance : their acid is
usually the malic.

815. Ord. Calycanthliceae. A small group of shrubs, between the

FIG. 814 Flowers of Calycanthus floridus. 815. Vertical section of a flower, showing the
hollow receptacle, &c ; the floral envelopes cut away. 810 A stamen, seen from without.
817. A pistil 818. Section of the ovary, showing the two ascending ovules. 819 The closed
pod-shaped receptacle in fruit 820. A vertical section of an achenium, showing the embryo
of the seed 821. Cross-section of an embryo, showing the strongly convolute cotyledons.

418 ILLUSTRATIONS OV Till! KATURAL ORDERS.

last order and the next, distinguished from Posacece by their oppo-
site leaves without stipules, and their convolute cotyledons : the
ovaries are enclosed in a fleshy calyx-tube as in a rose-hip. — It
comprises only two genera ; viz. Calycanthus (Carolina Allspice,
Sweet-scented Shrub, &c), and Chimonanthus, of Japan. They are
cultivated for their fragrant flowers The bark and foliage exhale
a slight camphoric odor ; and the flowers give a fragrance like that
of strawberries.

81G. Ol'd. IHyrtr.CeDC {Myrtle Family). Aromatic trees or shrubs,
with opposite and simple entire leaves, which are punctate with
pellucid dots, and often furnished with a vein running parallel with
and close to the margin, without stipules ; the calyx-tube adherent
to the ovary ; many stamens ; and seeds without albumen. — Ex.
Myrtus, the Myrtle, is the most familiar representative of this
beautiful tropical and subtropical order. The species abound in a
pungent and aromatic volatile oil, and an astringent principle.
Cloves are the dried flower-buds of Caryophyllus aromaticus. Pi-
mento (Allspice) is the dried fruit of Eugenia Pimenta. Cajeput
oil, a powerful sudorific, is distilled from the leaves and fruit of a
Melaleuca of the Moluccas. Australian species of Eucalyptus yield
a large quantity of tannin. The aromatic fruits of many species,
filled with sugar and mucilage, and acidulated with a free acid, are
highly prized ; such, for instance, as the Pomegranate, the Guava,
Pose- Apple, &c.

817. Ol'(l. Mclaslomaceac. Trees, shrubs, or herbs, with opposite
ribbed leaves', and showy flowers, with as many or twice as many
stamens as petals ; the anthers mostly appendaged and opening by
pores, inflexed in aestivation : further distinguished from Myrtaeeas
by (he leaves not being dotted ; and from Lythraeese by the adna-
tion of the calyx-tube (by its nerves at least) with the ovary. — Ex.
The beautiful species of Rhexia represent this otherwise tropical
order in the United States. The berries of Melastoma are eatable,
and tinge the lips black (like whortleberries) ; whence the generic
name.

818. Ol'd. LytliraceOC (Loosestrife Family) is distinguished among
these perigynous orders, with exalbuminous seeds, by its tubular
calyx enclosing the two — four-celled ovary, but entirely free from it.
The styles are perfectly united into one: the fruit is a thin capsule.
The stamens are inserted on the tube of the calyx below the petals.
— Ex. Ly thrum. Chiefly tropical, of little economical use.

EXOGENOUS Oil DICOTYLEDONOUS PLANTS.

419

819. Orel. Rllizoplioracca; {Mangrove Family) consists of a few
tropical trees (extending into Florida and Louisiana), growing in
maritime swamps, where they root in the mud, and form thickets
on the verge of the ocean. The ovary is often partly free from the
calyx, two-celled, with two pendulous ovules in each cell. Tiiese
plants are remarkahle for their opposite leaves, with interpetiolar
stipules, and for the germination of the embryo while within the
pericarp. — Ex. Rhizophora, the Mangrove (Fig. 141). The as-
tringent bark has been used as a febrifuge, and for tanning.

820. Ortl. CombrelaceiE consists of tropical trees or shrubs (which
have one or two representatives in Southern Florida), often apeta-
lous, but with slender colored stamens ; distinguishable from any of
the preceding orders of this group by their one-celled ovary, with
several suspended ovules, but only a solitary seed, and convolute
cotyledons. — Ex. Combretum.

821. Grd. OnagracCCB {Evening-Primrose Family). Herbs, or rare-
ly shrubby plants, with alternate or opposite leaves, not dotted nor

furnished with stipules. Flowers usually tetramerous. Calyx ad-
herent to the ovary, and usually produced beyond it into a tube.

TIG 822. Flower of Oenothera fruticosa 823. The same, with the petnls removed. 824.
Magnified grains of pollen, with some of the intermixed cellular threads. 825. Cross-section
of the four-lobed and four-celled capsule.

FIG 826. Ilippuris vulgaris (suborder Halorageic). 82" Magnified flower, with the sub-
tending leaf. S28. Vertical section of the ovary 8-X Vortical section of the lruit aud seed

420

ILLUSTRATIONS OF THE NATURAL ORDERS.

Petals usually four (rarely three or six, occasionally absent), and tlio
stamens as many, or twice as many, inserted into the throat of the
calyx. Ovary commonly four-celled : styles united. Fruit mostly
capsular. — Ex. Chiefly an American order ; many are ornamental
in cultivation. Fuchsia, remarkable for its colored calyx and ber-
ried fruit ; Oenothera (Evening Primrose) ; Epilobium, ■where the
seeds bear a coma ; Ludwigia, which is sometimes apetalous ; and
Circcea, where the lobes of the calyx, petals, stamens, cells of the
ovary, and the seeds, are reduced to two ; showing a connection with
the appended

822. Suboi'd. KaloragCtC, which are a sort of reduced aquatic Ona-
graceaa, often apetalous : the solitary seeds commonly furnished with
albumen. — Ex. Myriophyllum (Water-Milfoil) and Ilippuris (Horse-
tail), where the limb of the calyx is almost wanting; the petals
none ; the stamens reduced to a single one, and the ovary to a single,
cell, with a solitary seed.

823. Ord. Gl'OSSUlaceae ( Gooseberry Family ). Small shrubs, either
spiny or prickly, or unarmed ; with alternate, palmately lobed and

FIG. 830. The cultivated Gooseberry ; a branch in flower. 831 Branch in fruit S32
The calyx, beating the petals and stamens, cut away from the summit of the ovary (.S33), and
laid open. 831, 833 Sections of the unripe fruit 833 Magnified seed, with a conspicuous
rhaphe. 837. Longitudinal section of the same, showing the minute embr.,0 at the extrem-
it, of the albumen.

EXOGENOUS OR DICOTYLEDONOUS TLANTS.

421

veined leaves, usually in fascicles, often sprinkled with resinous dots.
Flowers in racemes or small clusters. Calyx-tube adherent to the
one-celled ovary, and more or less produced beyond it, five-lobed,
sometimes colored. Petals (small) and stamens five, inserted on
the calyx. Ovary with two parietal placenta; : styles more or less
united- Fruit a many-seeded berry. Embryo minute, in hard
albumen. — Ex. Ribes (Gooseberry and Currant). Never unwhole-
some : the fruit usually esculent, containing a mucilaginous and sac-
charine pulp, with more or less malic or citric acid. Two or three
red-flowered species of Oregon and California, and the fellow or
Missouri Currant, are ornamental in cultivation.

824. Ol'd. CactaCCfC {Cactus Family). Succulent shrubby plants,

the stems

peculiar in habit, with spinous buds, usually leafless
either globular and many-
angled, columnar with several
angles, or flattened and joint-
ed. Flowers usually large
and showy. Calyx of sev-
eral or numerous sepals, im-
bricated, coherent with and
crowning the one-celled ova-
ry, or covering its whole sur-
face ; the inner usually con-
founded with the indefinite
petals. Stamens indefinite,
with long filaments, cohering
with the base of the petals. 83S

Styles united : stigmas and parietal placentae several. Fruit a
berry. Seeds numerous, with a curved or fleshy and rounded em-
bryo, and little or no albumen. — All American, the greater part
Mexican or on the borders of Mexico. The common Opuntia
(Prickly Pear) extends north to New England: its mucilaginous
fruit is eatable. So is the sweet red pulp of the huge Cereus gigan-
teus of Sonora and South California, which forms a singular tree,
forty or fifty feet high. Cereus grandiflorus is the magnificent
Night-blooming Cereus.

825. Ol'd. LoasaceO:. Herbs usually clothed with rigid or stinging
hairs ; leaves opposite or alternate, without stipules ; the flowers
ehowy. Calyx-tube adherent to the one-celled ovary ; the limb

FIG. 833. Flower of Mamillaria caespitosa, of the Upper Missouri.

3G

422 ILLUSTRATIONS OF TIIK NATURAL ORDERS.

mostly five-parted. Petals as many, or twice as many, as the lobes
of the calyx. Stamens perigynous, indefinite, and in several parcels,
or sometimes definite. Style single. Ovary with three to five
parietal placenta). Seeds few or numerous, albuminous. — Ex. Lo-
asa, Mentzelia, Cevallia ; the latter with solitary seeds and no albu-
men. All American, and in the United States nearly confined to
the regions beyond the Mississippi. The bristles of Loasa sting
like nettles.

82G. Ol'd. Tlirncraceffi. Herbs, with the habit of Cistus or TTeli-
anthemum ; the alternate leaves without stipules. Flowers solitary,
showy. Calyx five-lobed ; the five petals and five stamens inserted
on its throat. Ovary free from the calyx, one-celled, with three
parietal placenta}. Styles distinct, commonly branched or many-
cleft at the summit. Fruit a three-valved capsule. Seeds numer-
ous (anatropous), with a crustaceous and reticulated testa, and a
membranaceous aril on one side. Fmbryo in fleshy albumen. — Ex.
Turnera, of which there is one species in Georgia.

827. Ord. Passi Horaces (Passion-flower Family). Herbs, or
somewhat shrubby plants, climbing by tendrils ; with alternate,
entire, or palmately-lobed leaves, mostly with stipules. Flowers
often showy. Calyx mostly of five sepals, united below, free from
the one-celled ovary ; the throat bearing five petals and a filament-
ous crown. Stamens as many as the sepals, monadelphous, and ad-
hering to the stalk of the ovary, which has usually three club-shaped
styles or stigmas, and as many parietal placentae. Fruit fleshy or
berry-like. Seeds numerous, with a brittle sculptured testa, enclosed
in pulp. Fmbryo enclosed in a thin albumen. — Ex. Passiflora (the
Passion-flower, Granadilla) : nearly all natives of tropical America.
Two species are found as far north as Virginia and Ohio. Many
are cultivated for their singular and showy flowers. The acidulous
refrigerant pulp of Passiflora quadrangularis (the Granadilla), P.
edulis, and others, is eaten in the West Indies, &c. But the roots
are emetic, narcotic, and pobonous.

828. Ol'd. Papayacerc comprises merely a small genus of tropical
dioecious trees, of peculiar character : the principal one is the Pa-
paw-tree (Carica Papaya) of tropical America, which has been in-
troduced into Fast Florida. The fruit, when cooked, is eatable ;
but the juice of the unripe fruit, as well as of other parts of the plant,
is a powerful vermifuge. The juice contains so much fibrine that it
has an extraordinary resemblance to animal matter : meat washed

EXOGENOUS Oil DICOTYLEDONOUS rr.ANTS. 423

in water impregnated with this juice is rendered tender : even the
exhalations from the tree are said to produce the same effect upon
meat suspended among the leaves.

829. Ord. CucurbilacefE {Gourd Family). Tender or succulent
herbs, climbing by tendrils ; with alternate, palmately veined or
lobed, rough leaves, and monoecious or dioecious flowers. Calyx of
four or five (rarely six) sepals, united into a tube, and in tlie fertile
flowers adherent to the ovary. Petals as many as tbe sepals, com-
monly more or less united into a monopetalous corolla, which co-
heres with the calyx. Stamens five or three, or rather two and a
half, i. e. two with two-celled anthers, and one with a one-celled an-
ther, inserted into the base of the corolla or calyx, either distinct or
variously united by their filaments, and long, sinuous or contorted
anthers (Fig. 4G5-4G7). Ovary one- to five-celled ; the thick and
fleshy placenta? often filling the cells, or diverging before or after
reaching the axis, and carried back to as to reach the walls of the
pericarp, sometimes manifestly parietal ; the dissepiments often dis-
appearing during its growth, sometimes only one-ovuled from the top :
stigmas thick, dilated or fringed. Fruit (pepo, Fig. 560) usually
fleshy, with a hard rind, sometimes membranous. Seeds mostly flat,
with no albumen. Embryo straight: cotyledons foliaceous. — Ex.
The Pumpkin and Squash (Cucurbita), Gourd, Cucumber, and
Melon. When the acrid principle which prevails throughout the
order is greatly diffused, the fruits are eatable, and sometimes deli-
cious : when concentrated, as in the Bottle Gourd, Bryony, &c, they
are dangerous or actively poisonous. The officinal Colocynth, the
resinoid and bitter pulp of the fruit of Cucumis Colocynthis, is very
acrid and poisonous ; and Elaterium, obtained from the juice of the
Squirting Cucumber, is still more violent in its effects. The seeds
of all are harmless.

830. Ord. CrasSUlacCBB (Stonecrop Family). Herbs, or slightly
shrubby plants, mostly fleshy or succulent ; remarkable for the com-
plete symmetry and regularity of their flowers (449, Fig. 3o9 -3G5).
Calyx of three to twenty sepals, more or less united at the base,
free from the ovaries, persistent. Petals as many as the sepals,
rarely combined into a monopetalous corolla. Stamens as many or
twice as many as the sepals, more or less perigynous. Pistils always
as many as (he sepals, distinct, or rarely (in Penthorum and Dia-
morpha) partly united : ovaries becoming follicles in fruit, several-
seeded. Embryo straight, in thin albumen. — Ex. Sedum (Stone-

421

ILLUSTRATIONS OF TIIF NATURAL ORDERS'.

crop, Orpine, Live-for-ever), Crassula, Sempervivum (Houseleek),
&c. They mostly grow in arid places, and are of no economical im-
portance.

83 1. Ord. SaxifragacCtC {Saxifrage Family). Herbs or shrubs,
with alternate or opposite leaves. Calyx of four or five more or
less united sepals, either free from or more or less adherent to
the ovary, persistent. Petals as many as the sepals, rarely want-
ing. Stamens as many, or commonly twice as many, as the pistils
or sepals, or rarely indefinitely numerous, perigynous. Ovaries
mostly two (sometimes three or four), usually united below and
distinct above, sometimes completely united and even the styles also.
Seeds numerous, with a straight embryo in fleshy albumen. The
order, taken in the largest sense, includes four tribes, as they should
probably be called, rather than suborders, which some botanists regard

even as distinct orders, viz. : The Saxifrages, or true Saxifrage
Family, which are herbs, with no manifest stipules, except the wings
or appendages at the base of the petiole or radical leaves. Ex. Sax-

FIG 839. Sullivantia Ohionis. 840. Flower with the calyx laid open, somewhat enlarged.
841. Fruit surrounded by the persistent calyx and withered petals, enlarged. 842. Section of
the lower part of the capsule, magnified ; showing the central placenta covered with the as-
cending Feeds 843 A magnified seed, with its cellular, wing-like testa. 844 Section of Um
nucleus, showing the embryo in the midst of albumen.

EXOGENOUS OR DICOTYLEDONOUS TLANTS. 425

ifraga, INIitellji, &c. Hoots somewhat astringent, in ITeuchefa" .co much
so that II. Americana is called Alum-root. IIyduangikje : shrubs,
with simple opposite leaves and no stipules. Ex. Hydrangea and
Philadelphia, the latter polyandrous. Baukrejk : Australian
shrubs, with opposite and compound sessile leaves and no stipules.
Cunonikje : woody plants, with opposite simple or compound leaves
and interpetiolar stipules. Escallokiex : woody plants, with
alternate simple leaves and no stipules. Ex. Escallonia, of South
America, Itea.

832. Ord. llamamelaceffi ( Witch-Hazel Family). Shrubs or small
trees, with alternate simple leaves, without stipules. Flowers often
polygamous. Petals valvate in aestivation. Stamens twice as many
as the petals, half of them sterile ; or numerous, and the petals none.
Summit of the two-celled ovary free from the calyx, a single ovule
suspended from the summit of each cell : styles two, distinct. Cap-
sule cartilaginous or bony. Seeds bony, with a small embryo in
hard albumen. — Ex. Ilamamelis (Witch-Hazel), Fothergilla. A
small order, of little importance. Ilamamelis is remarkable for
flowering late in autumn, just as its leaves are falling, and perfecting
its fruit the following spring. To this order is now appended the
genus Liquidambar, or Sweet-Gum, which has been taken as the
type of a distinct order ; but it is rather a reduced and apetalous
form of the present order. It may stand as a suborder, viz.

833. Subord. Balsamiflliae (Sweet- Gam Family), consisting of a
fi»w trees, with alternate palmately-lobed leaves, and deciduous
stipules ; the monoecious flowers in rounded aments or heads, desti-
tute of floral envelopes ; the indurated capsules forming a head :
they are two-beaked, opening between the beaks, the cells ripening
one or two seeds, although the ovules-are numerous. The Sweet-gum
is so called from a fragrant balsam or storax which it exudes.

834. Ord. Ulllbelliferffi (Parsley Family). Herbs, with hollow
stems, and alternate, dissected leaves, with the petioles sheathing
or dilated at the base. Flowers in simple or mostly compound um-
bels, which are occasionally contracted into a kind of head. Calyx
entirely coherent with the sui-face of the dicarpellary ovary; its
limb reduced to a mere border, or to five small teeth. Petals five,
valvate in aestivation, inserted, with the five stamens, on a disk
which crowns the ovary; their points inflexed. Styles two; their
bases often united and thickened, forming a stylopodium. Fruit
dry, a cremocarp, consisting of two united carpels, at maturity sepu-

426

ILLUSTRATIONS OF THE NATURAL ORDERS.

ruble from each other, and often from a slender axis (carpophore),
into two achenia, or mcricarps : the face by which these cohere re-
ceives the technical name of commissure : they are marked with a
definite number of ribs (juga), which are sometimes produced into
wings : the intervening spaces (intervals), as well as the commissure,
sometimes contain canals or receptacles of volatile oil, called vitta :
these are the principal terms peculiarly employed in describing the
plants of this difficult family. Embryo minute. Albumen hard or
corneous. — Ex. The Carrot, Parsnip, Celery, Caraway, Anise,

Coriander, Poison Hemlock, &c. are common representatives of this
well-known family. Nearly all Umbelliferous plants are furnished
with a volatile oil or balsam, chiefly accumulated in the roots and in
the reservoirs of the fruit, upon which their aromatic and carmina-
tive properties depend : sometimes it is small in quantity, so as
merely to flavor the saccharine roots, which are used for food ; as in
the Carrot and Parsnip. Put in many an alkaloid principle exists,
pervading the foliage, stems, and roots, especially the latter, which ren-

FIG. 845. Conium maeulatum (Poison Hemlock), n portion of the spotted stem, with n leaf;
end an urn bel with joung fruit 84G. A flowering umbcllet. 847. A flow or, enlarged 848 The
fruit. 849. Cross-section of the same, showing the involute (campylospcrmous) albumen of tho
two seeds. 850. Longitudinal section of oi.e lucricarp, exhibiting the minute, emk-jo near tha
apex Of the aibumeu.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

42;

clers them acrid-narcotic poisons. And, finally, many species of
warm regions yield odorous gum-resins (such as Galbanum, Assa-
fcetida, &c), which have active stimulant properties. The stems of
Celery (Apium graveolens), which are acrid and poisonous when
the plant grows wild in marshes, &c, are rendered innocent by

cultivation in dry ground, and by blanching. Among the virulent
acrid-narcotic species, the most famous are the Hemlock (Conium
macu latum), and Cicuta maculata (Cowbane, Water-Hemlock), indi-
genous to this country, the root of which (likft that of the C. virosa
of Europe) is a deadly poison. A drachm of the fresh root has
killed a boy in less than two hours.

835. Ord. AraliaceSB ( Ginseng or Ivy Family) scarcely differs from

the last in floral structure, except that the ovary is mostly composed
of more than two carpels, and these do not separate when ripe, but

FIG. 851. Flower of Osmorrhiza longistylis. 852. Umfcel of the same in fruit : a, the invo-
lucels 853. The ripe mericarps separating from the axis or carpophore. 854 Cross-section
of the fruit of Angelica, where the lateral ribs are produced into wings : the black dots repre-
sent the vittae, as they appear in a cross-section. 855. One of the mericarps of the same, show-
ing the inner face, or commissure, as well as the transverse section, with two of the vittae, a

FIG. 856 Flower of Aralia nudicaulis (Wild Sarsaparilla) ; a vortical section, displaying
two of the cells of the ovary. 857. Cross-section of the ovary. 858. Longitudinal section of a
seed, magnified, showing the small embryo at the upper end.

428 ILLUSTRATIONS OF THK NATURAL ORDERS.

become drupes or berries ; and the albumen is not hard like horn,
but only fleshy. — Ex. Aralia (the Spikenard, the Wild Sarsaparilla,
Ginseng), and Iledera (the Ivy). Their properties are aromatic,
stimulant, somewhat tonic, and alterative.

83G. Ol'd. Comaccrc ( Cornel or Dogwood Family). Chiefly trees or
shrubs ; with the leaves almost always opposite, destitute of stipules.
Flowers in cymes, sometimes in heads surrounded by colored involu-
cres. Calyx coherent with the two-celled ovary ; the very small
limb four-toothed. Petals four, valvate in aestivation. Stamens
four, alternate Avith the petals. Styles united into one. Fruit a
two-celled drupe. Embryo nearly as long as the albumen ; cotyle-
dons broad and flat. — Ex. Cornus, the Dogwood. Chiefly remark-
able for their bitter and astringent bark, which in this country has
been substituted for Cinchona. The peculiar principle they contain
is named Cornine. Cornus Canadensis (Fig. 321, 322) is a low
and herbaceous species. — A reduced form of this order occurs in
Nyssa (the Tupelo or Sour-Gum), which has dioecious or polyga-
mous flowers, the sterile ones at least apctalous, the fertile ones ap-
pearing to be so on account of the limb of the adherent calyx being
ob;olete ; the style stigmatic down one side and revolute ; the ovary
and drupe one-celled and one-seeded. The fruit is acid. The wood
of the common Sour or Black Gum-tree, or Peperidge, is close-
grained, and hard to split.

Division II. Monopetalous Exogenous Plants.

Floral envelopes consisting of both calyx and corolla : the petals
more or less united (corolla gamopetalou.-:). — A few true Ericaceae,
with all the Pyrolene and some Monotropese, are polypetalous : the
Aquifoliaceoe are nearly so, as are some of several of the succeeding
orders, and Fraxinus, &c. in Oleaceaj. The latter genus is apeta-
lous, and so are one or two genera in other generally Monopetalous
orders.

Conspectus of the Orders.

Group 1. Ovary coherent with the calyx, two- to several-celled, with one or
many ovules in each cell. Seeds albuminous, with a small embryo. Sta-
mens inserted on the corolla. Leaves opposite.

Stipules wanting. Capri foliaceje.

Stipules intcrpctiolar (or in one group the leaves whorlcd). Rubiace.e.

EXOGENOUS OR DICOTYLEDONOUS PLANTS. 429

Group 2. Ovary coherent with the calyx, ohe-ccllcd and onc-ovnled, or rarely
3 celled with two of the cells empty, and the third onc-ovulcd Seed with
little or no albumen Stamens inserted on the corolla. Limb of tho ca-
lyx a mere ring, crown, or pappus, or none. Stipules none.

Stamens distinct. Seed suspended. Leaves opposite. Stamens 3, or rarely 2.

Flowers often irregular. Valerianace^;.

Stamens 4 Flowers regular, in an involucrate head. DipsacejE.

Stamens syngenesious. Seed erect. Composite.

Group 3. Ovary coherent with the calyx, with two or more cells and numer-
ous ovules. Seeds albuminous. Stamens inserted with the corolla (epi-
gynous) : anthers not opening by pores. Juice more or less milky.

Corolla irregular. Stamens united by their anthers or filaments. Lobeliaceje.
Corolla regular. Stamens distinct. Campanulace^e.

Group 4. Ovary free from the calyx, or sometimes coherent with it, with two
or more cells and few or many ovules. Seeds albuminous. Stamens in-
serted with the corolla, or rarely somewhat coherent with its base, as many,
or twice as many, as its lobes : anthers mostly opening by pores or
chinks. Ericaceae.

Group 5. Ovary free, or rarely coherent with the calyx, several-celled, with a
single ovule (or at least a single seed) in each cell Seeds mostly albu-
minous. Stamens definite, as many as the lobes of the (often almost poly-
pctalous) corolla and alternate with them, or two to four times as many :
anthers not opening by pores. — Trees or shrubs.

Stamens as many as the lobes of the corolla : no sterile ones. Aquifoliaceje.
Stamens more numerous than the lobes of the corolla, and all fcitilc.

Flowers polygamous : calyx free. Ebenace.e.

Flowers perfect : calyx more or less adnatc. Stykacaceje.

Stamens as many fertile as the lobes of the corolla and opposite

them. Sapotace^e.

Group 6. Ovary free, or with the base merely coherent with the tube of the
calyx, one-celled, with a free central placenta. Stamens inserted into tho
regular corolla opposite its lobes ! which they equal in number. Seeds
albuminous.

Shrubs or trees (all tropical) : fruit drupaceous. Myrstnace^e.

Herbs : fruit capsular. Prjmulaceje.

Group 7. Ovary free, one-celled, with a single ovule ; or two-celled with
several ovules attached to a thick central placenta. Stamens as many as
the lobes of the regular corolla or the nearly distinct petals. Seeds albu-
minous.

Ovary two-celled : style single : stamens 4, or rarely less. Plantaginace^e.

Ovary one-celled : styles and stamens 5. Plumbaginacea:.

Group 8. Ovary free, or rarely partly coherent, one- or two- (or spuriously

430 ILLUSTRATIONS OF TIIIC NATURAL ORDIvRS.

four-) celled, with numerous ovules. Corolla bilabiate or irregular; tbe
stamens inserted upon its tube, and mostly fewer than its lobes.

Ovary 1-celled with a central placenta. Stamens 2. Lentibolace.e.

Ovary 1-ccllcd, or spuriously 2- 5 -celled with parietal placenta;.
Seeds very numerous and minute, albuminous.
Plants destitute of green herbage. Orobanchace^e.

Plants with green herbage. Gesneriace^e.

Seeds few or many, large : albumen none. Bignojjiace.e.

Ovary 2-ccllcd, with the placenta; in the axis.

Corolla convolute in activation. Seeds few ; no albumen. AcanthacevE.
Corolla imbricated in aestivation. Seeds albuminous. Scrophulariacejs.

Gioup 9. Ovary free, two- to four-lobcd, or at least separating or splitting
into as many one-seeded nuts or achenia, or drupaceous. Corolla tegular
or irregular ; the stamens inserted on its tube, equal in number or fewer
than its lobes. Albumen little or none.

Stamens 4, didynamous, or 2. Corolla more or less irregular.

Ovary not 4-lobed : style terminal. Verbenace;e.

Ovary of 4 lobes around the base of the style. Labiatve.

Stamens 5. Flower regular. Leaves alternate. Borraginace^e.

Group 10. Ovary free, compound, or rarely the carpels two or more and dis-
tinct : the ovules usually several or numerous. Corolla regular ; the sta-
mens inserted upon its tube, as many as the lobes and alternate with them.
Seeds albuminous.

riacenta; 2, parietal (sometimes expanded or united). Embryo minute.

Hairy herbs. Albumen cartilaginous. Hydrophillaceje.

Smooth herbs. Albumen fleshy. Gentianacea:.

Placenta; in the axis : ovary with 2, 3, or rarely several cells.

Embryo large, coiled or folded. Seeds few. Convolvulaceje.

Embryo straight, with broad cotyledons. Polemoxiackje.

Embryo curved, rarely straight, slender. Seeds numerous. Solaxace.e.

Group II. Ovaries 2 and distinct (or sometimes united), but the stigmas united
into one and often the styles also. Stamens as many as and alternate with
the lobes of the regular corolla, which is convolute, or rarely valvate in
aestivation. Anthers often connected with the stigma. Fruit usually a pair
of follicles. Seeds mostly numerous, often comose. Embryo large and
straight, in sparing albumen. Juice milky.

Pollen powdery. Apocynace^e.

Pollen in waxy or granular masses. Asclepiadace^e.

Group 1 2. Ovary free, two celled, the cells mostly two-ovulcd, and the fruit one-
seeded. Co:olhi regular (sometimes nearly polypetalous or wanting) ; the
stamens (two) fewer than its lobes. — Shrubs or trees.

Seeds erect. Corolla imbricated or contorted in aestivation. Jasmivace^e.

Seeds suspended. Corolla valvate in aastivation. Oleace^e.

EXOGENOUS Oil DICOTYLEDONOUS PLANTS. 431

837. Ord. CaprifoliacCiB (Honeysuckle Family). Mostly Bhrubs,
often twining, with opposite leaves, and no stipules (but Viburnum
often has appendages like them). Calyx-tube adnate to the 2— 5-
celled ovary; the limb 4-5-cleft. Corolla regular or irregular.
Stamens inserted on the corolla, as many as the petals of which it is
composed, and alternate with them, or rarely one fewer. Fruit
mostly a berry or drupe. Seeds pendulous, albuminous. — Ex. The
Honeysuckles (Lonicera), which have usually a peculiar bilabiate
corolla (473), the Snowberry (Symphoricarpus), Diervilla, which
has a capsular fruit, &c, compose the tribe Lonicereje, character-
ized by their tubular flowers and filiform style : while the Elder
(Sambucus) and Viburnum, which have a rotate or urn-shaped
corolla, form the tribe SasibucejE. Chiefly plants of temperate

regions. Several species, such as Honeysuckle, &c, are widely
cultivated for ornament. They are generally bitter, and rather
active or nauseous in their properties.

838. Ord. RubiacCJE (Madder Family). Shrubs or trees, or often
herbs, with the entire leaves either in whorls, or opposite and fur-
nished with stipules. Calyx-tube completely, or rarely incompletely

FIG. 859. Branch of Lonicera (Xvlosteon) oblongifoHa: the two evaries united! 800 Lo-
nicera (Caprifolium) parviflora. 801. A flower about the natural size. 832. Longitudinal sec-
tion of the ovary. 863. Longitudinal section of a magnified seed, showing the albumen and
minute embryo. •

432

ILLUSTRATIONS OF TIIK NATURAL ORDKRS.

atlnate to the 2 - 5-celled ovary ; the limb four- or five-cleft or
toothed, or occasionally obsolete. Stamens us many as the lobes of
the regular corolla, and alternate with them, inserted on the tube.
Fruit various. Seeds albuminous. — This extensive family divides
into two principal suborders, viz. : —

839. Sllboi'd. StclIatcaB {Madder Family proper). Herbs, with the
leaves in whorls ; but all except a single pair are generally supposed
to take the place of stipules. — Ex. Galium, Rubia (the Madder),
&c., nearly all belonging to the colder parts of the world. The roots
of Madder yield the important dye of that name ; and those of
several species of Galium are imbued with a similar red coloring-
matter.

840. Suboi'd. Cinchoncff (Peruvian-Bark Family). Shrubs, trees,
or herbs ; the leaves opposite and furnished with stipules, which are
very various in form and appearance. — Ex. Cephalanthus (Button-

brush), Pinkneya, and an immense number of tropical genera.
Very active, and generally febrifugal properties prevail in this large
order. It furnishes some of the most valuable known remedial
agents, among them Peruvian Bark or Cinchona, and Ipecacuanha.

?IG 864 Piece of Rubia tinetoria ( the Madder) in flower. 865 The fruit. 866 The two
constituent portions of the fruit separating 867 Vertical section of one carpel, showing the
curved embryo 8 '8 Section of a flower of Galium

FIG. 869. Cephalanthus occidentalis, tho Eutton-Bush. 870. A flower, ti'Uen from tha
head 87 1 The co-olla laid opea.

EXOGENOUS OU DICOTYLEDONOUS PLANTS.

433

The febrifugal properties of the former depend on the presence of
two alkaloids, Cinchonia and Quinia, both combined with Kinic acid.
The Quinquina barks, which are derived from some species of Ex-
ostemma and other West Indian, Mexican, and Brazilian genera,
contain neither cinchonia nor .quinia. The bark of Pinckneya pu-
bens, of the Southern United State?, has been substituted for Cin-
chona.— The true Ipecacuanha is furnished by the roots of Cepha-
aelis Ipecacuanha of Brazil and New Granada. Its emetic principle
(called Emetine) also exists in Psychotria emetica of New Granada,
which furnishes the striated, black, or Peruvian Ipecacuanha. The
order likewise furnishes Coffee, the horny seed (albumen) of Coffoea
Arabica. According to Blume, the leaves of the Coffee-plant are
used as a substitute for tea in Java. — To this order maybe ap-
pended, either as a suborder, or, as in a general work it is more con-
veniently regarded, the

841. Ol'd. Logailiacesc, which may be briefly said to be Rubiacere
with a free calyx, and manifestly connected with the Cinchoneaj
through the Iloustonia section of Oldenlandia, with a partly free

FIG 872. Oldenlandia (Iloustonia) carulea. 873, 874 The two sorts of flowers that differ-
ent individuals bear, with the corolla laid open ; one with the stamens at the base, the other
at the summit of the tube: the lower figure shows also a section of the ovary 875. Cross-
section of an anther, magnified. 876 Anther less enlarged, opening longitudinally. 877-
Capsule with the calyx. 878 879 Views of the capsule iu dehiscence. 880. Diagram of a
cross section of the unexpended flower.

37

434

ILLUSTRATIONS OF THIS NATURAL ORDERS.

calyx. On the other hand, they run close to Scrophulariacese and
Apocynaceae. — Spigelia Marilanclica (the Carolina Pink-root, a
well known vermifuge, of somewhat acrid-narcotic properties), and
Gelsemium (the so-called Yellow Jessamine of the Southern States)
are the most conspicuous representatives of the group in this coun-
try. The active properties of the family are most conspicuous in
species of Strychnos. The fatal drug, Niix-vomica, from which
strychnine is extracted, consists of the seeds of an East Indian
Strychnos. Tieate, another frightful poison, is prepared from a
Java species, and the Ouari poison of South America, from a third
species. Meanwhile a Brazilian species, S. Pseudoquina, has a harm-
less fruit, and its hark ( Copalche bark) is reputed to he an excellent
febrifuge, fully equal to Cinchona.

842. Ord. ValcrianacefB ( Valerian Family). Herbs with opposite
leaves, and no stipules. Flowers often in cymes, panicles, or heads.
Limb of the adnate calyx two- to four-toothed, obsolete, or else

885

forming a kind of pappus. Corolla tubular or funnel-form, some-
times with a spur at the base, four- or five-lobed. Stamens distinct,
inserted on the corolla, usually fewer than its lobes. Ovary one-

FIG. 881 Branch of Fedia Fagopyrum. 882 A magnified Tower 883. A fruit 884. An
enlarged cross-section of the same, and the cotyledons of the seed in the single fertile ceil : the
two empty cells are confluent into one. 8S5 Flower of a A'alerian, with one of the pappus-
like bristles of the calyx unrolled 88G. Section through the ovary and embryo ; the brUtles
of the calyx broken away.

EXOGENOUS OR DICOTVhKDONOL'9 PLANTS. 435

ovuled, with one perfect cell and two abortive ones. Fruit a kind
of achenium. Seed suspended, exalbuminous. Embryo straight,
radicle superior. — Ex. Valeriana, the Valerian, and Fedia, the Lamb'
Lettuce : the latter is eaten as a salad. The perennial species,
especially the roots, exhale a heavy and peculiar odor, have a some-
what bitter, acrid taste, and are antispasmodic and vermifugal.
Valerian of the shops is chiefly from Valeriana officinalis of the
South of Europe. It produces a peculiar intoxication in cats. The
large roots of V. edulis are eaten by the aborigines of Oregon.
The famous Spikenard of the ancients, esteemed as a stimulant
medicine as well as a perfume, is the root of a Nardostachys of the
Himalayas.

843. Ord DipsaceSE {Teasel Faynily). Herbs, with opposite or
whorled sessile leaves, destitute of stipules. Flowers in dense
heads, which are surrounded by an involucre. Limb of the adnate
calyx cup-shaped and entire or toothed, or forming a bristly or
plumose pappus. Corolla tubular ; the limb four- or five-lobed, some-
what irregular. Stamens four, distinct, or rarely united in pairs,
often unequal, inserted on the corolla. Ovary one-celled, one-ovuled.
Seed suspended, albuminous. — Ex. Dipsacus, the Teasel, and
Scabiosa, or Scabious. All natives of the Old World. Teasels are
the dried heads of Dipsacus fullonum, covered with stiff and spiny
bracts, with recurved points.

844. Ord. Composite (Composite or Sunflower Family). Herbs
or shrubs ; with the flowers in heads (compound flowers of the

older botanists, 394, Fig. 323-325), crowded on a receptacle, and
surrounded by a set of bracts (scales) forming an involucre ; the sep-
arate flowers often furnished with bractlets (chaff, palcce). Limb of
the adnate calyx obsolete, or a pappus (Fig. 569-573), consisting

FIG. 8S7. A head of flowers of Cichory (Fig 323) vertically divided.

436 ILLUSTRATIONS OF TIIK NATURAL ORDERS.

of hairs, bristles, scales, &c. Corolla regular or irregular. Sta-
mens five, as many as the lobes or teeth of the regular corolla, in-
serted on its tube : anthers united into a tube {syngencsious, Fig.
4G3, 4G4). Style two-cleft. Ovule solitary, erect, anatropous.
Fruit an aehenium (Fig. 568-573), either naked or crowned
with a pappus. Seed destitute of albumenn. Fmbryo straight. —
This vast but very natural family is divided into three series or
suborders ; \ iz. : —

845. Suboi'd. Tul)llliilcra\ Corolla tubular and regularly four- or
five-lobed, either in all the flowers (when the head is discoid), or in
the central ones (those of the disk) only, the marginal or ray flowers
presenting a ligulate or strap-shaped corolla. — Ex. Liatris, Fupato-
rium, t-c. ; where the heads are Itomogamous, that is, the flowers all
tubular, similar and perfect : Helianthus (Sunflower), Helenium,
Aster, &e. ; where the heads are heterogamous ; the disk flowers
being tubular and perfect, while those of the ray are ligulate, and
either pistillate only, or neutral, that is, destitute of both stamens
and pistils.

846. Subord. LanifitifloriC. Corolla of the disk-flowers bilabiate. —
Ex. Chaptalia, of the Southern United States ; and many South
American genera, &c.

847. Suboi'd. LigUliflora. Corolla of the flowers (both of the disk
and ray) all ligulate and perfect. — Ex. The Dandelion, Lettuce,
Cichory (Fig. 887), &c.

848. This vast family comprises about a tenth part of all Pha>
nogamous plants. A bitter and astringent principle pervades the
whole order ; which in some is tonic (as in the Chamomile, the
Boneset or Thoroughwort, &c.) ; in others, combined with mucilage,
so that they are demulcent as well as tonic (Elecampane and Colts-
foot) ; in many, aromatic and extremely bitter (such as Wormwood
and all the species of Artemisia) ; sometimes accompanied by acrid
qualities, as in the Tansy and the Mayweed, the bruised fresh herb-
age of which blisters the skin. The species of Liatris, which abound
in terebinthine juice, are among the reputed remedies for the bites
of serpents ; so are some species of Mikania in Central America.
The juice of Silphium and of some Sunflowers is resinous. The
leaves of Solidago odora, which owe their pleasant anisate fragrance
to a peculiar volatile oil, are infused as a substitute for tea. From
the seeds of Sunflower, and several other plants of the order, a bland
oil is expressed. The tubers of Helianthus tuberosus are eaten

EXOGENOUS OK DICOTYLEDONOUS PLANTS.

437

under the name of Jerusalem artichokes; Girasola, the Italian name
of Sunflower, having become Anglicized into Jerusalem. True arti-
chokes are the fleshy receptacle and imbricated scales of Cynara
Scolymus. The flowers of Carthamus tinctorius, often called Saf-
fron, yield a yellow dye, much inferior in quality to true Saffron.
— The Liguliflonu, or Ciehoraceae, all have a milky juice, which is
narcotic, and has been employed as a substitute for opium. The
bland young leaves of the garden Lettuce are a common salad. The

889 8S0 SS7 8S8

roasted roots of the Wild Succory (Cichorium Intybus) are ex-

FIG. 888. Head of Liatris squarrosa (discoid ; the flowers all tubular and perfect). 889.
The same, with the scales of one side of the imbricated involucre removed ; and alto all the
flowers but one, showing the naked flat receptacle 890. Portion of one of the plumose bris-
tles of the capillary pappus 891 Head of Ilelenium autumnale (heterogamous) , the rajs
neutral, consisting merely of a ligulate corolla 892 The same, with the flowers all removed
from the roundish receptacle, except a single disk flower and one or two rays : the refluxed
scales of the involucre in a single series. 893. Magnified disk-flower of the same : the corolla
exhibiting the peculiar venation of the family ; namely, the veins corresponding to the sinuses,
and sending a branch along the margins of the lobes. 894 The same, with the corolla re-
moved ; the achenium crowned with the limb of the calyx in the form of a chaffy pappus, of
about five scales. 895 A chaff of the pappus more magnified. 896 A tubular corolla of this
family laid open, showing the venation ; and also the five syngenesious anthers united in a
tube, through which the two-cleft style passes. 897. Head of Dracopis amplexicaulis, with
the flowers removed from the elongated spike-like receptacle except a few at the base : a,
achenium of one of the disk-flowers magnified, partly enclosed by its bractlet (chaff or
palua) ; the pappus obsolete 898 Part of the involucre and alveolate (honej comb-like) re-
ceptacle of Onopordon or Cotton-Thistle. 899 A perfect and ligulate flower of the Dandelion,
vritll itj hair-like or capillary pappus.

37*

408

ILLUSTRATIONS OF THE NATURAL ORDERS.

tensively used to .adulterate coffee : and the roots of some species
of Tragopogon (Salsify, Oyster-plant) and Scorzonera are well-
known esculents.

849. Ol'd. LobeliacefC (Lobelia Family). Herbs or somewhat
shrubby plants, often yielding a milky juice, with alternate leaves
and perfect flowers. Limb of the adnate calyx five-cleft. Corolla
irregularly five-lobed, usually appearing bilabiate, cleft on one side
nearly or quite to the base. Stamens o, epigynous, coherent into a
tube. Stigma fringed. Capsule one - several-celled, many-seeded.
Seeds albuminous. — Ex. Lobelia. All narcotico-acrid poisons.
The well-known Lobelia inflata (Indian Tobacco) is one of the most
powerful articles of the materia medica, and most dangerous in the
hands of the reckless quacks who use it. — This order is only a
form of the next, with irregular flowers.

850. Ord. CiimpailulacCft1 (Campanula Family). Herbs, like the
last, but the juice less acrid, and the corolla regular, eampanulate,

usually five-lobed, withering. Stamens five, distinct. Style fur-

TIG. 900 Campanula rotundifolia, much reduced in size. 901. Lobelia inflitta, reduced in
size 902. A flower, enlarged 903. The united filaments and anthers enclosing the style ; the
corolla and limb of the calyx cut away. 904. The stigma surrounded by a fringe 905 Trans,
verse section of a capsule. 90 '. Section of a magnified seed, showing the embryo.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

439

nished with collecting hairs. — Ex. Campanula (Bell-flower, Hare-
bell). Plants of little known importance to man, except for or-
nament.

851. Ord. Ei'icacCiE (Heath Family). Shrubs, or small trees, rarely
herbs. Flowers regular and symmetrical, or nearly so ; the petals
sometimes distinct. Stamens mostly distinct, free from the corolla,
as many or twice as many as its lobes, and inserted with it (either
hypogynous or epigynous) : anthers often appendaged, commonly
opening by terminal pores. Pollen compound (of four united
grains) except in the last suborder. Styles and stigmas united into
one. Ovary with two or more cells and usually numerous ovules,
free, or in Vaccinere coherent with the calyx-tube. Seeds usually
indefinite, albuminous. — Most botanists give the rank of orders to
the following suborders.

852. Sllbord. YaccillicfC ( Whortleberry Family). Ovary adnate to
the tube of the calyx, becoming a berry or drupaceous. Anthers
two-celled ; the cells nearly distinct, mostly prolonged above into a
tube. Shrubs, with scattered or alternate leaves, often evergreen. —
Ex. Vaccinium (Bilberry, Blueberry, Cranberry) and Gaylussacia
(Whortleberry or Huckleberry).

853. Sllboi'd. EriciliefB (True Heath Family). Ovary free from
the calyx. Fruit capsular, sometimes baccate or drupaceous.
Mostly shrubs. Leaves various, often evergreen. Petals rarely
distinct. — Ex. Erica (Heath), Kalmia, Rhododendron, Gaultheria,
Andromeda, &c.

FIG. 007 Branch of Rhododendron Lopponicum 008. Enlarged flower, with its pedicel and
bracts. 909. A flower with the corolla removed, more enla: < I 910 The capsule of II. maxi-
mum, opening by septicidal dehiscence ; the valves breaking away from the persistent axis,
or columella.

440

ILLUSTRATIONS OF THE NATURAL ORDERS.

854. Suboi'd. EpacridcSB (Epacris Family). Shrubby plants of
the Southern hemisphere, with the aspect and character of Heaths,
but the anthers one-celled are not appendaged.

855. Sllbord. PyrolCK (Pyrola Family). Ovary free from the
calyx. Petals distinct. Anthers two-celled. Fruit a capsule.
Seeds with a very loose cellular testa. Mostly herbs. Leaves flat
and broad, evergreen. — Ex. Pyrola, Chirnaphila.

856. Sllbord. MonotropCtC (Indian-Pipe Family). Ovary free from
the calyx. Petals distinct or united. Anthers two-celled, or con-
fluently one-celled. Pollen simple. Fruit a capsule Seeds with
a loose or winged testa. Parasitic herbs, destitute of green color,

FIG. 911 Gaultheria procumbens (Checkerberry, &c.) 912. The enlarging calyx in the im-
mature fruit. 913. Vertical section of the pulpy or berry-like calyx and the included capsule
(the seeds removed from the placenta in one cell). 914 Horizontal section of the same, show,
ing the five-celled capsule, with a placenta proceeding from the iuner angle of each cell 915.
Section of a seed, magnified. 916. Flower of a Vaccinium (Blueberry). 917 Vertical sec-
tion of the ovary and adherent calyx 918. Anther of Vaccinium Vitis-ldoea ; each cell pro-
longed into a tube, and opening by a terminal pore. 919 Anther of Vaccinium Myrtillus; the
connectivum furnished with two appendages. 920 Stamen of an Andromeda (Cassiope), show-
ing the appendages of the connectivum 921 Stamen of Aictostaph}los Uva-Ursi, showing
the separate auther-cells, opening by a terminal pore, the appendages of the connectivum, and
the filament, which is swollen at the base.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

441

and with scales instead of leaves. — Ex. Monotropa, the Indian-
Pipe and Pinesap.

857. In this diversified and widely diffused order, the bark and
foliage are generally astringent, often stimulant or aromatic from a
volatile oil or a resinous matter, and not seldom narcotic. Thus, the
leaves of Rhododendron, Kalmia, and all the related plants, are
deleterious (being stimulant narcotics), or suspicious. The honey
made from their flowers is sometimes poisonous. The Uva-Ursi
and the Chimaphila (Pipsissewa) are the chief medicinal plants of

926 932 H.9 931

the order. The berries are generally edible, and some are largely
used for the dessert ; as Cranberries, Blueberries, and Huckleber-
ries. The fleshy calyx of Gaultheria (Checkerberry, or Winter-
green) has a very pleasant and well-known aroma. Many Ericacene
are cultivated for ornament, especially Rhododendrons and Azaleas,
Heaths and Epacrises.

FIG. 922. Pyrola chlorantha, reduced in size. 923 Enlarged flower. 924. Mngnificd sta-
men 925. Pistil. 926 Cross-section of the capsule. 927. A highly magnified seed 928 The
nucleus removed from the loose cellular testa, and divided, showing the very minute euibrvo.

FIG. 929. Monotropa uniflora. 930. A petal. 931. Capsule with the stamens. 932 Trans-
verse section of the same ; the thick and lobed placenta covered with very minute seeds.

442

ILLUSTRATIONS OF THE NATURAL OKDERS.

858. Ol'll. AqilifoliaceJC (H6Vy Family). Trees or shrub?, com-
monly with coriaceous leaves, and small axillary polygamous flowers.
Calyx of four to six sepals. Corolla four- to six-parted or cleft :
the stamens as many as its segments and alternate with them, in'
serted on the base of the corolla. Anthers opening longitudinally.
Ovary two- to six-celled; the cells with a single suspended ovule.
Fruit drupaceous, with two to six nutlets. Embryo minute, in bard
albumen. — Ex. Ilex, the Holly, &c. The bark and leaves contain
a tonic, bitter, extractive matter. The leaves of a species of Ilex
are used for tea in Paraguay : and the famous black drink of the
Creek Indians is prepared from the leaves of Ilex vomitoria (Cas-
sena) ; which are still used as a substitute for tea in some parts o(
the Southern States.

859. Ord. Ebeiiacca; (Ebony Family). Trees or shrubs, destitute
of milky juice, with alternate, mostly entire leaves, and polygamous
flowers. Calyx three- to six-cleft, free from the ovary. Corolla
three- to six-cleft, often pubescent. Stamens twice to four times as
many as the lobes of the corolla, inserted on them. Ovary three- to
several-celled ; the style with as many divisions. Fruit a kind of
berry, with large and bony seeds. Embryo shorter than the hard

albumen. — Ex. Diospyros, the Persimmon. The fruit, which i?
extremely austere and astringent when green, becomes sweet and
eatable when fully ripe. The bark is powerfully astringent. Eb-
ony is the wood of Diospyros Ebenus and other African and Asiatic
species.

8G0. Ol'd. StjracacefB (Storax Family). Shrubs or trees, with per-

FIG. 933. Perfect flower of Diospj-ros Virginiana, the Persimmon 934. The corolla, laid
open, and stamens. 935. The fruit. 936 Section through the fruit and bony seeds. 937.
Vertical section of a seed. 938 The detached embryo.

EXOGENOUS OR DICOTYLEDONOUS PLANTS. 443

feet flowers. Calyx-tube generally coherent either with the base of
the ovary, or with its whole surface. Petals often distinct or nearly
so. Styles and stigmas perfectly united into one. Stamens definite,
or in the suborder SYMi'LOCiNE^i mostly indefinite ; filaments more
or less united. Cells of the ovary opposite the calyx-lobes. Other-
wise much as in the last family. — Ex. Styrax, Halesia, Symplocos.
Some yield a fragrant, balsamic resinous substance ; such as Storax
and Benzoin, containing Benzoic acid. The sweet leaves of our
Symplocos tinctoria afford a yellow dye.

8C1 . Ord. SapotaoeE (Sapodilla Family). Trees or shrubs, usually
with a milky juice ; the leaves alternate, entire, coriaceous, the up-
per surface commonly shining. Flowers perfect, regular, axillary,
usually in clusters. Corolla four- to eight- (or many-) cleft. Sta-
mens distinct, inserted on the tube of the coiolla, commonly twice
as many as its lobes, half of them fertile and opposite the lobes, the
others petaloid scales or filaments and alternate with them : anthers
extrorse. Ovary 4-12-celled, with a single ovule in each cell.
Styles united into one. Fruit a berry. Seeds with a bony testa,
with or without albumen. — Ex. Bumelia, of the Southern United
States. The fruit of many species is sweet and eatable ; such as
the Sapodilla Plum, the Marmalade, the Star-Apple, and other West
Indian species. The large seeds, particularly of some kinds of
Bassia, yield a bland fixed oil, which is sometimes thick and like
butter, as in the Chee of India (B. butyracea), and the African
Butter-tree.

8G2. Ol'd. MminacerT. Trees or shrubs, mostly with alternate
coriaceous leaves, which are often dotted with glands; and with all
the characters of Primulacea?, except the drupaceous fruit and arbo-
rescent habit. — Nearly all tropical (Ardisia, Myrsine).

863. Ord. Primulacea? {Primrose Family). Herbs, with opposite,
whorled, or alternate leaves, often with naked scapes and the leaves
crowded at the base. Flowers regular. Stamens inserted on the
tube of the corolla, as many as its lobes and opposite them ! Ovary
free, with one partial exception, one-celled with a free central pla-
centa ! Ovules mostly indefinite and amphitropous. Style and
stigma single. Fruit capsular : the fleshy central -placenta attached
to the base of the cell. Seeds albuminous. Embryo transverse. —
Ex. Primula (Primrose), Cyclamen, Anagallis. In Samolus, the
calyx coheres with the base of the ovary, and there is a row of
sterile filaments occupying the normal pooition of the first set of

444

ILLUSTRATIONS OF TIIK NATURAL ORDERS.

stamen?, namely, alternate with the lobes of the corolla. Several
are ornamental in cultivation, such as Primroses and Auriculas.

864. Onl. Plailtaginaccae {Plantain Family). Chiefly low herbs,
with small spiked flowers on scapes, and ribbed radical leaves. —
Calyx four-deft, persistent. Corolla tubular or urn-shaped, scarious
and persistent; the limb four-cleft. Stamens four, rarely two, in-
serted on the tube of the corolla alternate with its segments ; the per-
sistent filaments long and flaccid. Ovary two-celled : style single.
Capsule membranaceous, circumcissile ; the cells one- to several-
seeded. Embryo large, straight, in fleshy albumen. — Ex. Plantago,
the Plantain, or Ribgrass, is the principal genus of the order. Of no
important economical qualities.

865. Ordi Plumbagiliaceffi (Leadwort Family). Perennial herbs,

FIG. 939 Primula Mistassinica. 940. The corolla removed ; its tube laid open. 941 Tbe
calyx di\ ided vertically, showing the pistil. 942 Vertical section of the ovary nnd of the free
central placenta, covered with ovules, which nearly fills the cell. 943. Capsule of Primula
veris, dehiscent at the summit by numerous teeth 944. A magnified seed. 945 Section of
the same, exhibiting the transverse embryo

FIG 946. Branch of Anojnllis arvensis (Pimpernel), with a capsule showing the line of cir-
cumcissile dehiscence 94T The capsule (pyxis), with the lid falling away.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

445

or somewhat shrubby plants ; -with the flowers often on simple or
branching scapes, and the leaves crowded at the base, entire, mostly
sheathing or clasping. — Calyx tubular, plaited, five-toothed, persist-
ent. Corolla salver-shaped, with a five-parted limb, the five stamens
inserted on the receptacle opposite its lobes (Plumbago) ; or else of
five almost distinct unguiculate (scarious or coriaceous) petals, Avith
the stamens inserted on their claws ! (Statice, &c.) In the former

951 SSO 953 853

949 6.8 6-7

case the five styles are united nearly to the top ; but in the latter
they are separate ! Ovary one-celled, with a single ovule pendulous
from a strap-shaped funiculus which rises from the base of the cell.
Fruit a utricle, or opening by five valves. Embryo large, in thin
albumen. — Ex. Statice (Marsh-Rosemary or Sea-Lavender) and
Armeria (Thrift) ; sea-side or saline plants. They have astringent
roots ; none more so than tho:e of our own Marsh-Ro emary or Sea-
Lavender, one of the purest astringents of the materia medica.

8G6. Orel. LentiblllacCiC (Bladdencori Family). Small herbs, grow-
ing in water, or wet places, with the flowers on scapes ; the leaves
either submersed and dissected into filiform segments resembling
rootlets, and commonly furnished with air-bladders to render them

FIG. 948. A flower of Plantago major, enlarged. 949 Piftil 950 Capsule (pyxis,) with
the marcescent corolla. 951 Cross-section of a pod and seeds. 952. Vertical section of a seed

FIG 953 Corolla, and 954. cahx of Thrift (Armeria vulgaris). 955 Pistil with distinct
styles 956 Cross-section of the pod and seed. 957. Vertical section of the ovary, magnified,
to show the ovule.

38

446

ILLUSTRATIONS OF THE NATURAL ORDKRS.

buoyant, sometimes evanescent or wanting, or when produced in
the air entire and somewhat fleshy, clustered at the base of the
scape. Flowers showy, very irregular. Calyx of two sepals, or
unequally five-parted. Corolla bilabiate, personate ; the very short
tube spurred. Stamens two, inserted on the upper lip of the co-
rolla: anthers confluently one-celled. Ovary free, one-celled with a
free central placenta ! bearing numerous ovules. Seeds destitute of
albumen. Embryo straight. — Ex. Utricularia (Bladderwort), Pin-
guicula. Unimportant plants.

8G7. Ord. OrobancliacetE {Broom-Rope Family). Herbs, destitute
of green foliage, and with scales in place of leaves, parasitic on the
roots of other plants. Corolla withering or persistent, with a bila-
biate or more or less irregular limb. Stamens four, didynamous,

inserted on the corolla. Ovary free, one-celled, with two parietal
placenta^, ! which are often two-lobed, or divided. Capsule enclosed

FIG 958 Branch of Epiphegus Virginiana (Beech-drops), nearly of the natural size : the
lower flowers, with short imperfect corollas, alone producing ripe seeds. 959. A flower en-
larged. 9C0. Longitudinal section of the same 961 Longitudinal section of the ovary, more
magnified, showing one of the parietal placentae covered with minute ovules 962. Cross-sec-
tion of the same, showing the two parietal placenta? 963 A highly magnified seed. 931.
Section of the same, exhibiting the minute embryo next the hilum.

FIG. 965 Aphyllon uniflorum 966 A flower about the size of nature 967 The same
laid open, showing the didynamous stamens and the pistil 9^.8 A magnified anther. 969. A
magnified seed 970. Section of the same

EXOGENOUS Oil DICOTYLEDONOUS PLANTS. 447

in the persistent corolla. Seeds very numerous, minute. Embryo
minute at the extremity of the albumen. — Ex. Orobanche, Epi-
phegus (Beech-drops), &c. Astringent, bitter, and escharotic. The
pulverized root of Epiphegus (thence called Cancer-root) is applied
to open cancers.

868. Ol'd. Gcsnei'iacCBC, consisting chiefly of tropical herbs or tender
shrubby plants, with green foliage and showy flowers, the calyx
often partly adherent to the ovary, agrees with Orobanchacese in the
parietal placentation, structure of the seeds, &c. Many are culti-
vated in conservatories for ornament, such as species of Gloxinia
and Achimenes.

869. Ol'd. BignoniaceS {Bignonia Family). Mostly trees, or
climbing or twining shrubby plants, with large and showy flowers,
and opposite, simple, or mostly pinnately-compound leaves. Corolla
with a more or less irregular five-lobed or bilabiate limb. Stamens
five, of which one, and often three, are reduced to sterile filaments
or rudiments (Fig. 409), or four and didynamous. Ovary one-
celled with two parietal placenta?, or two-celled by a false partition
stretched between the placentas, or rarely by their meeting in the
axis. Pod two-valved, many-seeded. Seeds winged (Fig. 601),
destitute of albumen. Cotyledons foliaceous, flat, heart-shaped, also
notched at the apex. — Ex. Bignonia, Tecoma (Trumpet-creeper),
Catalpa, and other tropical genera. Of little importance, except as
ornamental plants.

870. Subord. Sesames (Sesamum Family) has few and wingless
seeds ; the fruit generally indurated or drupaceous, often two- to
four-horned, sometimes perforated in the centre from the dissepi-
ments not reaching the axis before they diverge and become pla-
centiferous, and spuriously four- to eight-celled by the cohesion of
parts of the placentas with the walls of the pericarp. — Ex. Sesa-
mum, Martynia (Unicorn-plum), and a few tropical plants. They
are mucilaginous ; and the seeds of Sesamum yield a good fixed oil.

871. Subord. Cresccntiece, consists of the Calabash-tree (Crescentia
Cujete) and a few allies, among them Parmenticra edulis, the Can-
dle-tree of Panama, which aho have wingless seeds. The subacid
pulp of the gourd-like fruit is edible ; the hard shell is used for bot-
tles, or calabashes.

872. Ol'd. Acanlhacea3 (Acanthus Family). Herbs or shrubby
plants, with bracteate showy flowers, and opposite simple leaves,
without stipules. Corolla bilabiate, or sometimes almost regularly

448

ILLUSTRATIONS OK THE NATURAL ORDERS.

five-lobed, convolute in aestivation ! Stamens four and didynamous,
or only two, the anterior pair being abortive or obsolete. Ovary
two-celled, with the placentas in the axis, often few-ovuled. Seeds
(sometimes only one or two in each cell) usually supported by
hooked processes of the placenta, destitute of albumen. The classi-
cal Acanthus is the type of this large and chiefly tropical order : its
gracefully lobed and sinuated leaves furnished the ornament of the
Corinthian capital. They are emollient plants, or some of them
bitter or slightly acrid : of little economical use. Several are culti-
vated for ornament.

873. Ol'd. Scroplililariaceae {Figwort Family). Herbs, or some-
times shrubby plants, with opposite, verticillate, or alternate leaves.

Corolla bilabiate, or more or less irregular ; the lobes imbricated in
aestivation. Stamens four and didynamous (Fig. 407), the fifth or
upper stamen sometimes appearing in the form of a sterile filament

FIG. 971. Branch of Gerardia purpurea. 972. Corolla, of the natural size, laid open. 973.
Calyx and style of the same. 974. Magnified transverse section of the capsule, with one of the
valves removed.

FIG 975. Gratiola aurea, natural size. 976. Corolla laid open, showing the two perfect
stamens and two rudimentary filaments as well as the pistil. 977 The perfect stamens aud
eteiile filament of Cheloue. 97S. Flower of a Linaria (Toadflax).

EXOGKXOUS OR DICOTYLEDONOUS PLANTS.

449

(Fig. 408), or very rarely antheriferous, or often only two, one
pair being either suppressed or reduced to sterile filaments. Ovary
free, two-celled, with the placenta? united in the axis. Capsule two-
valved. Seeds indefinite, or sometimes few, albuminous. Embryo
small. — Ex. Scrophularia, Verbascum (Mullein, which is remarkable
for the almost regular corolla, and the five often nearly perfect sta-
mens), Linaria, Antirrhinum (Snapdragon), &c. — The plants of this
large and important order are generally to be suspected of delete-
rious (bitter, acrid, or drastic) properties. The most important me-
dicinal plant is the Foxglove (Digitalis purpurea), so remarkable for
its power of lowering the pulse. Numerous species are cultivated
for ornament.

874. Orel. YerbenaceflB ( Vervain Family). Herbs, shrubs, or often
trees in the tropics, mostly with opposite leaves. Corolla bilabiate,
or the four- or five-lobed limb more or less irregular. Stamens
mostly four and didynamous, occasionally only two. Ovary free,

entire, two- to four-celled. Fruit drupaceous, baccate, or dry, and
splitting into two to four indehiscent one-seeded portions. Seeds with
little or no albumen. Embryo straight, inferior. — Ex. Verbena
(Vervain) is the principal representative in cooler regions. There
are many others in the tropics ; one of which is the gigantic Indian
Teak (Tectona grandis), remarkable for its very heavy and durable

FIG. 979 and 980. Flower of a Verbena enlarged 9S1. The corolla laid open. 982. Pistil
983 The fruit. 984. Cross-section of the young fruit and the contained seeds. 985 Fruit
separating into its four cocci. 986 Cross-section of one of the cocci, and a vertical section of
the lower part, showing the surface of the contained seed. 987. A'ertical section through
the pericarp, seed, and embryo.

38*

450

ILLUSTRATIONS OF THE NATURAL ORDERS.

wood. The loaves of Lippia citridora of the gardens yield an agree-
ahle perfume. Others are bitter and aromatic.

875. Sllboi'd. 1 PhrymaceSE (founded on Phryma, of a single species)
is separated on account of its simple pistil, uniovulate ovary, spirally
convolute cotyledons, and superior radicle.

876. Ol'd. Labiala; (Labiate or Mint Family). Herbs, or some-
what shrubby plants, with quadrangular stems, and opposite or
sometimes whorled leaves, replete with receptacles of volatile oil.
Flowers in axillary cymules, rarely solitary. Corolla bilabiate (Fig.
458). Stamens four, didynamous, or only two, one of the pairs
being abortive or wanting. Ovary free, deeply four-lobed; the cen-
tral style proceeding from between the lobes. Fruit consisting of
four (or fewer) little nuts or achenia, included in the persistent
calyx. Seeds with little or no albumen. — Ex. The Sage, Rose-

989 10C2 1001

mary, Lavender, Thyme, Mint, &c. are familiar representatives of
this universally recognized order. Their well-known cordial, aro-
matic, and stomachic qualities depend upon a volatile oil, contained
in glandular receptacles which abound in the leaves and other her-
baceous parts, with which a bitter principle is variously mixed.

877. Ord. BorraginaCCffi (Borage Family). Herbs, or sometimes
shrubby plants, with round stems, and alternate rough leaves ; the

FIG. 988 Flower of Nepeta (Glechoma) hederacca, or Ground Ivy. 989 Approximate
anthers of one pair of stamens, magnified. 990. Flower of a Lamium. 991. Corolla of h.
amplexicaule (Dead Nettle), laid open, showing the didynamous stamens, &c. 992. Calyx and
corolla of Scutellaria galericulata (Skull-cap) 993. Section of the enlarged calyx of the same,
bringing to view the deeply four-lobed ovary 994 Cross-section of a magnified achenium.
995. Vertical section of the same, showing the embryo 996. Flower of Teucrium Canadense.
997. Magnified anther of the same. 998 Stamen of the Thyme. 999. Flower of Monarda.
1000 Magnified anther of the same. 1001. Flower of a Salvia ; the calyx as well as the corolla
bilabiate. 1002 Magnified stamen of the same, with widely separated anther-cells, one of
which (a) is pollimferous, the other (b) imperfect.

EXOGENOUS OR DICOTYLEDONOUS TLAXTS.

451

flowers often in one-sided scorpioid clusters (407). Calyx of five
leafy and persistent sepals, more or less united at the base, regular.
Corolla regular ; the limb five-lobed, often with a row of scales in
the throat. Stamens as many as its lobes and alternate with them.
Ovary deeply four-lobed, the style proceeding from the base of the
lobes, which in fruit become little nuts or hard achenia. Seeds with
little or no albumen. — Ex. Borage, Lithospermum, Myosotis, Cyno-
glossum (Hound's-Tongue), Heliotropium, &c. In Echium, the limb
of the corolla is somewhat irregular, and the stamens unequal. In-
nocent mucilaginous plants with a slight astringency : hence demul-
cent and pectoral ; as the roots of the Comfrey. The roots of An-

chusa tinctoria (Alkanet) and Lithospermum canescens, &c. (used
by the aborigines under the name of Puccoon) yield a red dye.

878. Sllbord. ? Cordiiicea; consists of tropical woody plants, with
the ovary entire (not four-lobed), but in fruit drupaceous or dry and
indehiscent, four-seeded. The cotyledons of Cordia are plaited lon-
gitudinally (and are often edible), and the style is twice forked.

879. Ord. HydrophyllaceSB ( Water-leaf Family). Herbs, usually
with alternate and lobed or pinnatifid leaves ; the flowers mostly
in cymose clusters or unilateral racemes. Calyx five-cleft, with the

FIG. 1003. Myosotis, or Forget-me-not 1004 The rotate corolla laid open, showing ths
scales of the throat, and t^e short stamens. 1005. The pistil with its four-lobed ovary. 1006.
The calyx in fruit ; two of the little nuts having fallen away from the receptacle 1007 Sec-
tion of a nut, or rather achenium, showing the embryo 1008 Raceme of Symphytum offici-
nale (Comfrey). 1009. A corolla laid open ; exhibiting the lanceolate and pointed scales of the
throat, alternate with the stamens.

432

ILLUSTRATIONS OF THE NATURAL ORDKRS.

sinuses often appendaged, persistent. Corolla regular, imbricated or
convolute in aestivation, usually furnished with scales or honey-bear-
ing grooves inside ; the five stamens inserted into its base, alternate
with the lobes. Ovary free, with two parietal placenta;, which in
Ilydrophyllum dilate in the cell and appear like a kind of inner peri-

carp in the capsular fruit. Styles partly united. Seeds few, or
sometimes numerous, amphitropous, crustaceous. Embryo small,
in hard albumen. — Ex. Hydrophyllum, Nemophila, and Phacelia;
nearly all North American plants, some of them handsome and now
well known in cultivation. To this order, as a tribe, is now joined
the Hydrole.* (formerly the order Hydroleaceee), having often
entire leaves, two distinct styles, a commonly two-celled ovary by
the union of the two placenta? in the axis, and numerous seeds
with a fleshy albumen. These are chiefly tropical or subtropical
herbs, or low shrubs.

FIG. 1010. Ilydrophyllum Virginicum. 1011. A flower, nearly of the natural size 1012.
Corolla laid open. 1013. Capsule, with the persistent calyx and style. 1014. Magnified seed
1015 Section of the same 101(3. Highly magnified einhryo.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

453

880. Oi'd. Folcmor.iacecE (Polernonium Family). Herbs with alter-
nate or opposite leave?, and panicled, corymbose, or clustered flow-

1021 1022

ers. Calyx five-cleft. Corolla regular, with a five-lobed limb, con-
volute in aestivation. Stamens five, inserted on the corolla alternate

1032 1030

with its lobes, often unequal. Ovary free, three-celled, with a thick

FIG 1017. Flowers of Polemonium. 1018. Flowers of Phlox. 1019. Corolla of the same,
laid open, showing the stamens unequally inserted on its tube. 1020 Pistil of the same.
1021. Cross-section of the capsule of Polemor.ium. 1022. Cross-section of a magnified seed.
1023. Perpendicular section of the same 1024 Magnified embryo. 1025. Cross-section of the
dehiscent capsule of Collomia 1026, 1027. Capsule of Leptodactj Ion.

FIG. 1028. Pyxidanthcra barbulata, of the Pine-barrens of New Jersey, natural size 1029.
Pistil, in fruit, and calyx, enlarged 1030 Corolla and stamens. 1031. Same, laid open.
1032 A separate stamen, magaiaoi 1033. Sectiou u. the dahlscest capsule. 1034. A seed.

454

ILLUSTRATIONS OF THK NATURAL ORDERS.

axis, bearing few or numerous ovules : styles united into one : stig-
mas three. Capsule three- valved, loculicidal ; the valves also usu-
ally breaking away from a thick central column which bears the
seeds. Embryo straight, in fleshy or horny albumen. — Ex. Pole-
monium (Greek Valerian), Phlox, Gilia. Chiefly North Amer-
ican ; many are very common ornamental plants in cultivation. %To
this order Diapensia and Pyxidanthera (formerly the order Dia-
pensiacece) are now appended, with some doubt. They are two
low, tufted or prostrate, sufTruticose plants, with crowded and ever-
green, heath-like leaves, and solitary flowers : their principal peculi-
arity is found in the transversely dehiscent anthers.

881. Ord. CunvolvulaceJE (Convolvulus Family). Twining or trail-
ing herbs or shrubs, with more or less milky juice ; the leaves alter-
nate, and the flowers regular. Calyx of five imbricated sepals, per-
sistent. Corolla supervolute in aestivation ; the limb often entire
(Fig. 452). Stamens five, inserted on the tube of the corolla near
the base. Ovary free, two- to four-celled, with one or two erect
ovules in each cell. Capsule two- to four- (or by obliteration one-)
celled ; the valves often falling away from the persistent dissepi-
ments (septifragal, Fig. 587). Seeds large, with a little mucilagi-
nous albumen : embryo curved, and the foliaceous cotyledons usually

crumpled (Fig. 122, 123).— Ex. Morning-Glory, Bindweed. They
contain a peculiar strongly purgative resinous matter, which is

FIG 1035. Ipomoea purpurea 1036 The pistil. 1037 Section of the capsule, and of the
two seeds in each cell 103S Cupsule (reduced in size), when the valves have fallen away from
the dissepiments; and one of the seeds 1039 Magnified cross-section of a seed. 1040. Km-
brvo, with the leaf like two-lobed cotyledons spread out. 1041. Same, with the two cotyledons
Separated and laid open. •

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

455

chiefly found in their thickened or tuberous roots. Convolvulus
Jalapa, and other Mexican species, furnish the Jalap of the shops.
The more drastic Scammony is derived from the roots of C. Scam-
monia of the Levant. There is much less of this in those of Con-
volvulus panduratus (Man-of-the-Earth, Wild Potato-vine) : while
those of C. macrorhizus of the Southern States, which sometimes
weigh forty or fifty pounds, are farinaceous, with so slight an ad-
mixture of this matter as to be quite inert ; as is also the case with
the Batatas, or Sweet Potato, an important article of food. — To this
family are appended, as tribes or suborders,

882. Sllboi'd. Dichondreffi. Ovaries two to four, either entirely
distinct or with their basilar styles more or less united in pairs.
Creeping plants, with axillary, scape-like, one-flowered peduncles. —
Ex. Dichondra.

883. Subord. CllSCUtineiE. Ovary two-celled ; the capsule opening
by circumcissile dehiscence, or bursting irregularly. Embryo fili-
form, and spirally coiled in fleshy albumen, destitute of cotyledons !

Parasitic, leafless, twining herbs, destitute of green color. Stamens
usually furnished with fringed scales within. — Ex. Cuscuta (Dodder).

FIG. 1042. A piece of Cuscuta Grouovii, the common Dodder of the Northern United States,
cf the natural size 1043. A flower, enlarged. 1044. The same, laid open. l'!45 Section of
the ova y. 1046 Section of the capsule aud seeds. 1047. The spiral embryo detached. 1048.
The same in germination.

456

ILLUSTRATIONS OF THE NATURAL ORDERS.

884. Ord. SolaiiaCCiC (Nightshade Family) differs from Serophu-
lariaceae chiefly in the regular (rarely somewhat irregular) flowers,
with as many fertile stamens as there are lobes to the corolla, (four
or five), and some form of the plaited or valvate aestivation of the
corolla. Fruit either capsular or baccate. Embryo slender, mostly
curved, in fleshy albumen (Fig. G14, 615). — The fruit of Datura
is spuriously four-celled. — Stimulant narcotic properties pervade the
order, the herbage and fruits of which are mostly deleterious, often
violently poisonous, and furnish some of the most active medi-
cines; such as the Tobacco, the Henbane (Hyoscyamus niger), the

Belladonna (Atropa Belladonna), the Thorn-apple or Jamestown
Weed (Datura Stramonium), and the Bittersweet (Solanum Dulca-
mara). Yet the berries of some Solanums are eatable (as Toma-
toes, the Egg-Plant, &c), and the starchy tubers of the Potato
are a great staple of food. But the fruit and seeds of Capsicum
( Cayenne pepper) are most pungent and stimulant.

885. Ol'd. Gcntianacefe (Gentian Family). Herbs, with a watery
juice ; the leaves opposite and entire. Flowers regular, often showy.
Calyx of usually four or five persistent, more or less united sepals.
Corolla mostly convolute in aestivation ; the stamens inserted on its
tube. Ovary one-celled, with two parietal and many-ovuled pla-

FIG. 1049 Flower of Tobacco (Xicotiana Tabacum). 1050 The capsule, dehiscent at the
apex, with the persistent calyx. 1051. Cross-section of the same. 1052. Magnified section of
the seed of Solanum 1053. Flower of Hyoscyamus niger. 1054 Fruit (pyxis) of the same.
1055. Flowers oud berries of Solanum Dulcamara.

EXOGENOUS OR DICOTYLEDONOUS TLANTS.

457

centre, sometimes the ovules dispersed over the whole cavity of the
ovary, or nearly so. Capsule many-seeded. Seeds often very small,
with fleshy albumen and a minute embryo. — Ex. Gentiana, Frasera
(the American Columbo). A pure bitter and tonic principle ( Gen-
tianine) pervades the whole order. Gentiana lutea of Middle
Europe furnishes the officinal Gentian, for which almost any of our
species may be substituted. The above applies to the proper Gen-
tian Family. Obolaria differs in the imbricative aestivation of the

corolla : as to the ovules lining the whole cavity of the ovary, this
is also the case in Bartonia (Centaurella, 3fichx.), and in some Gen-
tians.— The Buckbean is the type of the tribe MenyanthidEjK,
which has alternate, sometimes trifoliolate or toothed leaves, and a
valvate-induplicate aestivation of the corolla.

88G. Ord. ApocynacetC {Dogbane Family). Trees, shrubs, or herbs,
with milky juice, and opposite entire leaves, without stipules.
Flowers regular. Corolla five-lobed, mostly convolute or twisted
in aestivation. Filaments distinct ; the anthers sometimes slightly
connected : pollen powdery. Ovaries two, distinct, or rarely syn-
carpous, but their styles or stigmas combined into one. Fruit com-
monly a pair of two follicles. Seeds often with a coma. Embryo
large and straight, in albumen. — Ex. Apocynum (Dogbane), Vinca

FIG 1056. Flower of Gentiana angustifolia 1057. Corolla, and 1058, the. calyx, laid open.
1059 The pistil. 1060 Cross-section of the pistil, showing the parietal attachment of the
ovules. 1061. Ripe capsule of G. saponaria, rai-ed on a stipe: the persistent withering
corolla, &c torn away. 1062. A magnified seed, with its large and loose testa. 1063 Leaf of
Limnanthemum lacunosum, bearing the flowers on its petiole !

39

458

ILLUSTRATIONS OF THE NATURAL ORDERS.

(Periwinkle), Nerium (Oleander), and a great number of tropical
shrubs and trees. In nearly all, the juice is drastic or poisonous ;
it often yields Caoutchouc ; which in Sumatra is obtained from Ur-
ceola elastica, and in Madagascar from Vahea. Strangely enough
some species yield a sweet and harmless milk, such as Tabenirc-
montana utilis, one of the South American Cow-trees. Also the
fruit of several species is edible and even delicious ; that of others
is a deadly poison. One kernel of Tanghinia venenifera of Mad-

agascar will kill twenty people. The inner bark of Dogbane makes
a strong cordage, whence its name of Indian Hemp.

887. Ord. AscIcpiadaceE {Milkweed Family). Herbs or shrubs,
with milky juice, and mostly opposite entire leaves ; mainly differ-
ing from the preceding order (as they do from all other Exogenous
plants) by the peculiar connection of the stamens with the stigma,
and the cohesion of the pollen into wax-like or granular masses,
which are attached in pairs to five glands of the stigma, and re-
moved from the anther-cells usually by the agency of insects (Fig.
541—545). Fruit consisting of two follicles. Seeds usually with
a silky coma and a large embryo. — Ex. Asclepias (Milkweed, or
Silkweed). The juice of the A. tuberosa (Pleurisy-root, Butterfly-
weed) is 'not milky. In all, it is bitter and acrid, and contains
Caoutchouc. The roots, &c. are diaphoretic, emetic, or cathartic.
The inner bark yields abundance of very long and fine, extremely

FIG. 1064 Apocynum androsasuiifolium. 10G5. Flower, of the natural size. 1066 Sta-
mens with the anthers conniveut around the pistils 1067. The pistils with their large com-
mon stigma. 1068. Seed with its coma, or tuft of silky hairs.

EXOGENOUS OU DICOTYLEDONOUS PLANTS.

459

Strong fibres. The singular structure of the blossom may be learned
from Fig. 541-545, and the subjoined illustrations.

888. Ord. JasminacetC {Jessamine Family) consists of a few chiefly
Asiatic shrubs, with compound leaves and fragrant flowers ; differ-,
ing from Oleacerc by the imbricated or twisted aestivation of the
hypocrateriform corolla, the erect seeds, &c. — Ex. Jasminum, the
Jessamine. Cultivated for ornament, and for their very fragrant
blossoms. — Menodora, or Bolivaria, has mostly simple leaves and
four ovules in each cell, but evidently pertains to this order.

889. Ord. Oleaceae (Olive Family). Trees or shrubs, with oppox
site leaves, either simple or pinnate. Calyx persistent. Corolla

FIG. 1069. Flower-bud of the common Milkweed (Asclepias Cornuti). 1070 Expanded
flower ; the calyx and corolla reflexed ; showing the stamiueal crown 1072. One of the hood-
ed appendages of the latter removed and seen sidewise, with its included process or horn.
1073/A vertical section of a flower (the hooded appendages removed) through the tube of sta-
mens, the thick stigma, ovaries, &c. 1074 Flower with the calyx and the fertilized enlarging
ovaries, crowned with the large stigma common to the two, from the angles of the peltate sum-
mit of which the pairs of pollen-masses, detached from the anther cells, hang by their stalks or
caudiele from a gland. 1075 Fruit (follicle) of the Common Milkweed 1076. Cross-section
of the last, in an early state. 1077. Detached placenta in fruit, covered with seeds 1078.
Seed (cut across), with its coma 1079 Section of the seed, parallel with the cotyledons.
1080 Vertical section of the seed perpendicular to the face of the cotyledons.

460 ILLUSTRATIONS OF THE NATURAL ORDERS.

four-cleft, or of four separate petals, valvate in aestivation, sometimes
none. Stamens mostly two, adnate to the base of the corolla.
Ovary free, two-celled, with two pendulous ovules in each cell.
Fruit by suppression usually one-celled and one- or two-seeded.
Seed albuminous. Embryo straight. — Ex. Olea (the Olive), and
Chionanthus (Fringe-tree), where the fruit is a drupe. Syringa, the
Lilac, which has a capsular fruit. Fraxinus, the Ash ; where the
fruit is a samara, the flowers are polygamous, and mostly destitute
of petals. Olive oil is expressed from the esculent drupes of Olea
Europaia. The bark, like that of the Ash, is bitter, astringent, and
febrifugal. Manna exudes from the trunk of Fraxinus Ornus of
Southern Europe, &c. — Forestiera appears to represent another
entirely apetalous form of this family.

Division III. — Apetalous Exogenous Plants.

Corolla none ; the floral envelopes consisting of a single series
(calyx), or sometimes entirely wanting. — Many of them are apeta-
lous allies of polypetalous families ; as Phytolaccaceae, &c. related to
Caryophyllaceaj ; Empetraceae to Ericaceae, &c.

Conspectus of the Orders.

Group I. Flowers perfect, with a conspicuous or colored mostly adnate calyx.
Ovary several-celled and many-ovuled. Capsule or berry many-seeded. —
Herbs or climbing shiubs. Abistolociiiace^e.

Gioup 2 Flowers perfect, or .rarely polygamous. Calyx corolline, strongly
gamoscpalous, much produced beyond the ovary, the expanded border entire
or moderately lobed ; the base persistent, and forming an indurated nut-
like closed covering to the onc-sccdcd achenium or utricle. Embryo large,
curved or conduplicatc, involving some albumen. — Leaves opposite : nodes
tumid. Flowers often large and showy. Nyctaginace^e.

Group 3. Flowers perfect, or rarely polygamous, with a regular and often
pctaloid calyx. Ovary free. Ovules solitary in each ovary or.cell. Em-
bryo curved or coiled around (or sometimes in) mealy albumen, rarely in the
axis or cxalbuminous.

Ovary several-celled, or ovaries several in a whorl. Phytolaccace.^

Ovary solitary and one-celled, with a single ovule.

Stipules none. Ovule campylotropous or amphitropous.

EXOGENOUS OR DICOTYLEDONOUS PLANTS. 461

Calyx eorollinc, double. Stamens pcrigynous. BasellacejE

Calyx not eorollinc : no scarious bracts. Chenoi'Odiace.e.

Calyx and bracts scaiious, sometimes colored. Amarantack;e<

Stipules sheathing. Calyx coiolline. Ovule orthotropous. Polygonace.e

Group 4. Flowers perfect, polygamous or dioecious, not disposed in aments,
with a regular and often pctaloid calyx. Style or stigma one. Ovarjl
onc-ccllcd, with one or few ovules : but the fruit one-celled and one-seeded.
Embryo not coiled around albumen. — Trees or shrubs, rarely herbs.

Calyx free from the ovary, and not enveloping the fruit.

Flowers polygamo-diceeious. Anthers opening by valves. Lauraceje.

Flowers perfect. Anthers opening longitudinally. Thymklace.e.

Calyx free, but baccate in fruit and enclosing the achenium. Eleagnace.e.
Calyx adnate to the ovary. Ovule destitute of coats.

Ovules several, pendulous from a stipe-like placenta. Santalace;e.

Ovule solitary, suspended. Parasitic shrubs. Lorantiiacea:.

Group 5. Flowers perfect, in spikes which often appear like aments, achlamvdc-
ous. Ovaries solitary or several, with one or few erect or ascending
orthotropous ovules. Embryo minute, enclosed in a persistent embryo-sac
at the apex of the albumen. — Herbs or shrubby plants, with tumid nodes.

Ovaiy one, one-ovuled. Stipule opposite the leaf or none. Piperace;e.

Ovaries more than one. Stipules, when present, in pairs. Saururace.-e.

Group 6. Flowers perfect or diclinous, frequently destitute of both calyx and
corolla. — Submersed or floating aquatic herbs.

Flowers monoecious. Fruit onc-ccllcd, one-seeded. CERATOniTLLACi:^;.

Flowers mostly perfect. Fruit four-celled, four-seeded. Callitriciiaceje.

Flowers mostly perfect. Pod several-celled, several-seeded. Podostemace.e.

Group 7. Flowers monoecious or dioecious, not amentaceous. Fruit capsular
or drupaceous, with two or more cells, and one (or rarely two) seeds in
each cell. Embryo straight in the axis of the albumen. — Herbs, shrubs,
or trees.

Fruit mostly dry. Juice milky. Pollen simple. Euphoreiace^e.

Fruit drupaceous. Pollen compound ; the grains in fours. EiirETEACEyE.

Group 8. Flowers monoecious, dioecious, or polygamous, with a regular calyx
which is free from the one-celled (or rarely two-celled) ovary and one-
seeded fruit (achenium, drupe, or samaral, but sometimes enclosing it.
Embryo curved, or straight, with the radicle superior, in albumen when
there is any. — Inflorescence various, often in spikes, heads, or a sort of
aments. Urticace^e.

Group 9. Flowers monoecious or dioecious, the sterile, and frequently the fertile
also, in aments, or in heads or spikes. Calyx of the fertile flowers, if any,
adherent. Ovary often two- to several-celled, but the fruit always one-
celled. — Trees or shrubs.
30*

462

ILLUSTRATIONS OF THE NATURAL ORDERS.

Stipules sheathing. Nutlets club-shaped, in globular heads.
Stipules not sheathing or none.
Sterile flowers only amentaceous.
Fruit a kind of drupaceous nut. Leaves pinnate.
Fruit a dry nut, involucrate. Leaves simple.
Both kinds of flowers amentaceous.
Fruit a samara or a small dry drupe.
Ovary one-celled : ovule solitary, erect.
Ovary two-celled, two-ovuled : ovule pendulous.
Fruit a many-seeded follicle : seeds with a coma.

Platan ace^e.

juglandack^e.
Cupulikeua;.

Myricace/e.
Betulack^e.
Salicace.e.

890. Ord. Al'istolochiaceiE {Blrthwort Family). Herbaceous or
climbing shrubby plants, with alternate leaves. Flowers brown
or greenish, usually solitary. Calyx-tube more or less united with
the ovary ; the limb valvate. Stamens six to twelve, epigynous, or
adherent to the base of the short and thick style : anthers adnate,

1C81 1083

extrorse. Ovary 3-G-eelled. Capsule or berry three- to six-celled,
many-seeded. Embryo minute, in fleshy albumen. — Ex. Asarum
(Wild Ginger, Canada Snakeroot), Aristolochia (Virginia Snake-
root). Pungent, aromatic, or stimulant tonics ; generally termed
Snakeroots, being reputed antidotes for the bites of venomous snakes.

FIG 10S1 Asarum Canadense. 1082. Calyx displaced, and a vertical section through the
rest of the flower 1083. Cross-section of the ovary ; the upper portion (from which the limb
of the calyx is cut away) showing the stamens, the united styles, &c. 1081. A separate sta-
men, enlarged. 1085. Vertical section of a seed.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

4G3

891. Ord. RafflcsiacCiC .: parasitic flowers, or flower-clusters (152), of
which the most striking is the gigantic KafTlesia Arnoldi of Sumatra
(Fig. 150), perhaps as much related to the last order as to any.

892. Ord. Nj'Ctaginacca' (Four-o'clock Family). Herbs or shrubs,
with opposite leaves ; distinguished by their tubular and funnel-form
calyx, the upper part of which resembles a corolla, and at length
separates from the base, which latter hardens and encloses the one-
celled achenium-like fruit, appearing like a part of it. Stamens hy-
pogynous, 1 - 20. Embryo coiled around mealy albumen (Fig. GIG,
G17) ; cotyledons large. Flowers involucrate. Mirabilis (Four-
o'clock) has a one-flowered involucre exactly like a calyx, while the
real calyx resembles the corolla of a Morning-Glory. Abronia has
only one cotyledon to its embryo ! — Plants of warm latitudes ; many
occur on our Southwestern frontiers.

1091 1083

893. Ord. PhytolaCCacCS! {Poke-weed Family). Chiefly represented

FIG 10S6, 108T. Phytolacca d»candra (Pokeweed). 10S3 A flower. 10S9. Unripe fruit
1090. Cross-section of t'.ie same, a little enlarged 1091. Magnified seed 1092 Section of the
same across the embryo. 1093. Vertical section, showing the embryo coiled around the albu-
men into a ring 1094. Magnified detached embryo.

4G4

ILLUSTRATIONS OF THE NATURAL ORDERS.

by the common Poke (Phytolacca decandra), which has a compound
ovary of ten confluent (one-seeded) carpels, the short styles or stig-
mas distinct; the fruit a berry. The root is acrid and emetic: yet
the young shoots in the spring are used as a substitute for Aspara-
gus. The berries yield a copious deep-crimson juice.

894. Ol'll. CasellacCX ; a small subtropical group of climbing suc-
culent plants, allied to the last and the next two orders, from which
it differs by the decidedly perigynous stamens and double petaloid
calyx. The ovary is single and one-ovulcd. — Ex. Basella, Pous-
singaultia of South America ; the latter cultivated for ornament (from
potato-like tubers) under the name of Madeira Vine. Some are pot-
herbs.

89o. Ord. Clienopodiaceoc (Goosefoot Family). Chiefly weedy
herbs, with alternate or opposite and more or less succulent leaves,

and small herbaceous flowers. Calyx sometimes tubular at the
base, persistent ; the stamens as many as its lobes, or fewer, and in-
serted at their base. Ovary free, one-celled, with a single ovule
arising from its base. Fruit a utricle (Fig. 574) or achenium.
I^mbryo curved or coiled around the outside of mealy albumen, or
spiral without any albumen (in Salsola, &c). — Ex. Chenopodium,
Atriplex, Peta (the Peet), &c. Sea-side plants, or common uejds :

JTG. 1095 Part of the spike of Salicornia herbacea: the flowers placed three together In
excavations of the stem, protected by a fleshy scale 1093 Separate flower. 1097 A flower
of Blitum, with its I'eshy cal) x and single stamen 109S Same, more enlarged, with the thick-
ened juicy calyx (1099) removed 1100. The ripe fruit 1101. Same, divided vertically, show-
ing the embrjo coiled around the central albumen. 1102. Flower of Chenopodium album
(common Goosefoot). 1103 Section of the same, more enlarged 1104 Section of t!ie utiiclo
and seed, showing the embryo 1105. Calyx of Salsola kali (Saltwort), in fruit, with its wing-
like border 1106. Section of the same, briuging the ovary into viuw. 1107. The spirally
coiled embryo of Chenopodina maritima.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

4G5

some are pot-herbs, such as Spinach : a few are cultivated for their
esculent roots ; as the Beet, 'which yields sugar. Soda is extract-
ed from the maritime species, especially from those of Salsola and
Salicornia (Samphire, Glass-wort). Chenopodium anthchninticum
yields the well-known Worm-seed oil.

89G. Ortl. AmnrailtacCiE (Amaranth Family). Flowers in heads,
spikes, or dense clusters, imbricated with dry and scarious bracts
which are often colored. Calyx of three to five sepals, which are
dry and scarious like the bracts. Stamens five or fewer, hypogy-
nous, distinct or monadelphous : anthers frequently one-celled. Utri-
cle often opening as a pyxis (Fig. 575). Embryo annular, always
vertical. Otherwise nearly as in Chenopodiaeea\ — Amarantus,
&c. A few Amaranths (Coxcomb, &c.) and Globe Amaranths
(Gomphrena) are cultivated for ornament. But most of the family
are coarse and homely weeds (Pigweeds, &c).

897. Ord. Polygon acCiE (Buckwheat Family). Herbs with alter-
nate leaves; remarkable for their stipules (ochreic, Fig. 305), which

TIG. 1108. Polygonum Pennsylvanlcum. 1109. Flower, laid open. 1110. Section of the
ovary, showing the erect ovule. 1111. Section of the seed, showing the embryo, at one side of
albumen.

4G6

ILLUSTRATIONS OF THE NATURAL ORDERS.

usually form sheaths around the stems above the leaves, and for
their orthotropous ovules (Fig. 518, 52G). Stamens definite, inserted
on the petaloid calyx. Fruit achenium-like. Embryo curved, or
nearly straight, applied to the outside (rarely in the centre) of
starchy albumen (Fig. GOG). — Exs Polygonum, Rumex (Dock,
Sorrel), Rheum (Rhubarb). The stems and leaves of Rhubarb
and Sorrel are pleasantly acid : while several Polygonums (Knot-
weed, Smart-weed, Water Pepper, &c.) are acrid or rubefacient.
The farinaceous teeds of P. Fagopyrum (the Buckwheat) are used
for food. The roots of most species of Rhubarb are purgative : but
it is not yet known what particular species of Tartary yields the
genuine officinal article. The Eriogone^e (a large tribe of the
southern and western parts of North America, chiefly west of the
Rocky Mountains) are remarkable for their exstipulate leaves and
involucrate flowers.

898. Ord. LauraceSD (Laurel Family). Trees or shrubs, with
pellucid-punctate alternate leaves, their margins entire. Flowers
sometimes polygamo-dioecious. Calyx of four to six somewhat
united petaloid sepals, which are imbricated in two series, free
from the ovary. Stamens definite, but usually more numerous than
the sepals, inserted on the base of the calyx : anthers two- to four-
celled, opening by recurved valves ! Fruit a berry or drupe, the
pedicel often thickened. Seed with a large almond-like embryo,

destitute of albumen. — Ex. Laurus, Sassafras, Benzoin. All aro-
matic plants, almost every part abounding in warm and stimulant

FIG. 1112 A staminate, and 1113, a pistillate flovrcr of Sassafras. 1114. A stamen with its
glands at the base : the anthers opening by two sets of valves. 1115. Pistil ; the ovary divid-
ed 1110 Branch in fruit. 1117 Section of the drupe and seed.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

4G7

volatile oil, to which their qualities are due. Camphor is obtained
from Camphora officinarum of Japan, China, &c. Cinnamon is the
bark of Cinnamomum Zeylanicum ; Cassia bark, of Cinnamomum
aromaticum of China, The aromatic bark and wood and the very
mucilaginous leaves of our own Sassafras are well known. Our
Benzoin odoriferum is the Spice-wood, or Feverbush. Laurus
nobilis is the true Laurel, or Sweet Bay. Persea gratissima, of the
West Indies, bears the edible Avocado pear.

899. Ord. Thymclacca: (Mezereum Family). Shrubby plants, with
perfect flowers, and a very tough bark ; the tube of the petaloid
calyx being free from the (one-ovuled) ovary ; its lobes imbricated
in aestivation ; the pendulous seed destitute of albumen. Stamens
often twice as many as the lobes of the calyx, inserted upon its tube

or throat. — Ex. Daphne and Dirca (Leather-wood, Moose-wood,
Wickopy, which is the only North American genus). The tough
bark is acrid, or even blistering, and is also useful for cordage. The
reticulated fibres of the liber in the Lagetta or Lace-bark of Jamaica
may be separated into a kind of lace. The berries are more or
less deleterious.

900. Ord. EIcagnaceJE {Oleaster Family). Shrubs or small trees,
with the flowers more commonly dioecious ; readily distinguished
from the preceding by having the foliage and shoots covered with
scurf, by the ascending albuminous seed, and the persistent tube of

FIG. 1118. Flowering branch of Dirca palustris 1119. A flower
open and enlarged. 1121 Branch in fruit.

468

ILLUSTRATIONS OF THE NATURAL ORDKRS.

the calyx, which, although free from (lie ovary, becomes succulent,
like a berry in fruit, and constricted at the throat, enclosing the
crustaceous achenium. — Ex. Eleagnus, Shepherdia. Plants of no
economical importance, except that a few are cultivated for their
silvery foliage. The fruit is sometimes eaten, as is that of the Buf-
falo-berry (Shepherdia argentea) and Silver-berry (Eleagnus ar-
gentea) by the Northern aborigines.

901. Ord. ProtcaceflB (Protect Family). A rather large family of
shrubs and trees of Southern temperate and subtropical regions,
chiefly of the Cape of Good Hope and Australia (a few in South
America, &c), with rigid coriaceous leaves, perfect flowers, either
regular or irregular, mostly in heads or spikes ; the lobes of the
calyx valvate in aestivation ; a stamen borne on each of its four
lobes ; the pistil simple and free, forming a mostly dehiscent fruit ;
seeds with a large and straight embryo, and no albumen. Many
of these plants are prized in conservatories for their beauty or sin-
gularity : the seeds of a few species are eaten.

902. Ord. Santalaceee (Sandal-wood Family). Trees, shrubs, or
sometimes herbs (their roots inclined to form parasitic attach-
ments) ; with alternate entire leaves, and small (very rarely dioe-

cious) flowers. Calyx-tube adherent to the ovary ; the limb four-
or five-cleft, valvate in aestivation ; its base lined with a fleshy disk,
the edo-e of which is often lobed. Stamens as many as the lobes of

FIG 1122 Branch of Comandra umbellata. 1123 Enlarged flower, laid open 1124. Ver-
tical section of a flower 1125 One of the segments of the calyx, enlaiged, showing the tuft
of hairs which connects its surface with the anther ! 1126 The fruit, reduced in size.

EXOGENOUS OR DICOTYLEDONOUS TLANTS. 4G0

the calyx, and opposite them, inserted on the edge of the disk.
Ovules several, destitute of proper integuments, pendulous from the
apex of a stipe-like basilar placenta. Style one. Fruit indehiscent,
crowned with the limb of the calyx. Seed albuminous. Embryo
small. — Ex. Comandra, Pyrularia, &c. The fragrant Sandal-wood
is obtained from several Indian and Polynesian species of Santalum.
The large seeds of Pyrularia oleifera (Buffalo-tree, Oil-nut), of the
Alleghany Mountains, would yield a copious fixed oil. One species
of Fusanus in Australia is esteemed for its edible seeds, known by
the name of Quandang-nuts.

903. Oril. Lorfintliacea: {Mistletoe Family) consists of shrubby
plants, with articulated branches, and opposite coriaceous and mostly
dull greenish entire leaves ; parasitic on trees. The floral envelopes
are various. In Mistletoe (which is dioecious) the anthers are ses-
sile and adnate to the face of the sepals, one to each ; while Lo-
ranthus has both calyx and corolla, the latter most conspicuous, and
a stamen before each petal and adnate to it. The ovary is one-
celled, with a single suspended ovule, consisting of a nucleus without
integuments. Fruit a one-seeded berry. Embryo small, in fleshy
albumen. — Ex. Loranthus ; Viscum, the Mistletoe, from the glu-
tinous berries of which birdlime is made ; Phoradendron, the Ameri-
can Mistletoe. The bark is astringent.

904. Ol'd. PipcraceOB {Pepper Family). A peculiar order of tropical
herbaceous or shrubby plants, with jointed stems, naked (achlamyde-
ous) but perfect flowers in spikes or spicate racemes, a one-celled ovary
with an erect orthotropous ovule ; the embryo minute in a vitellus
or persistent embryo-sac at the apex of the albumen. — Pungent
and stimulant properties characterize the order. Piper nigrum fur-
nishes Black pepper, and White pepper is the same, with the flesh of
the drupe removed. The fruit of Cubeba officinalis, &c furnishes
Cubebs, which are hot aromatics, acting also on the mucous mem-
branes. The pungency in all these plants is owing to a peculiar
volatile oil and resin. They also yield a crystalline matter, called
Piperine. Others have more intoxicating properties, as Betel, the
leaves of a Chavica, chewed by the Malays, and the Ava (Macropi-
per methysticum) from which the South-Sea Islanders make their
inebriating drink.

905. Ord. SaUl'UraCCSB {Lizard 's-tail Family) ; differs from the Pep-
per Family (of which it is an offshoot) in the feebly pungent quali-
ties, the distinct stipules (when these are evident), and the three or

40

470

ILLUSTRATIONS OF Til IC NATURAL ORDKRS.

more ovaries, separate or somewhat united, with one or more ovules
in each. — Ex. Saururus, Ilottuynia : a small group.

1138 113

906. Ord. Ccratophyllaceac {Hornwort Family) consists of the single
genus Ceratophyllum (growing in ponds and streams in many parts
of the world) ; distinguished by the whorled and dissected leaves
with filiform segments ; the flowers moncecious and sessile in the
axil of the leaves ; the stamens indefinite, with sessile anthers ; and
the simple one-celled ovary, which forms a beaked achenium in fruit,
containing an orthotropous suspended seed, with four cotyledons !
and a manifest plumule.

907. Ord. CallitrichacefC (Water- Starwort Family), formed of the
genus Callitriche ; aquatic annuals, with opposite entire leaves ; the
axillary flowers (either perfect or monoecious) with a two-leaved

FIG. 1127. Saururus cernuus. 1128 A separate flower with its bract and a part of the
axis magnified 1129 A more magnified anther, discharging its pollen from one cell. 1130
Cross-section of the ovary. 1131 A'ertical section of one of the carpels in fruit, and of the
contained seed, with the sac at the extremity of the albumen, containing the minute embryo.
1132 A seed. 11C3 Same, with the outer integument (testa) removed, showing the vitellus.
1134 The latter, Highly magnified. 1135 Section of the same, showing the enclosed heart-
shaped cnibrj o.

EXOGENOUS On DICOTYLEDONOUS PLANTS.

471

involucre, but entirely destitute of calyx and corolla ; stamen one
(or rarely two), hypogynous, with a slender filament, and a reni-
form confidently one-celled anther ; the ovary four-lobed, four-celled,
indehiscent in fruit ; the seeds albuminous.

908. Ord. Podostemaceae (River-iceed Family) comprises a few
(chiefly American and Asiatic) aquatics, in rivers, with the aspect
of Mosses, Hepaticre, &c. ; their small flowers arising from a spathe ;
the calyx often entirely wanting ; the stamens frequently unilateral
and monadelphous ; the ovary two- or three-celled, with distinct
styles ; in fruit forming a ribbed capsule, containing numerous ex-
albuminous seeds attached to a central column. — Ex. Podostenion.

909. Ol'd. EuphorbiaceJE (Spurge Family). Herbs, shrubs, or
trees, often with a milky juice : in northern temperate climes chiefly
represented by the genus Iuiphorbia ; which is remarkable for hav-
ing numerous staminate flowers, reduced to a single stamen (487),
enclosed in an involucre along with one pistillate flower, this reduced
to a compound pistil, and also achlamydeous, or with an obsolete
calyx. But other genera have a regular calyx both to the staminate
and pistillate flowers ; and a few are likewise provided with petals.
Ovary of two to nine more or less united carpels, coherent to a cen-
tral prolongation of the axis : styles distinct, often two-cleft. Fruit
mostly capsular, separating into its elementary carpels, or cocci
(usually leaving a persistent axis) : these commonly open elastically

FIO. 113G. Callitricho verna, about the natural size. 1137. Perfect flowers, magnified.
1138. A staminate and pistillate flo-.ver, magnified. 1139. The fruit. 1140. Cross-section of
the fruit. 1141. Vertical section through the pericarp, seeds, and embryo.

472

ILLUSTRATION'S OF Till: NATURAL ORDERS.

by one or both sutures. Seed with a large embryo in fleshy albu-
men, suspended. — Ex. Euphorbia (Spurge), Croton, Buxus (the
Box). Acrid and deleterious qualities pervade this large order,

chiefly resident in the milky juice. But the starchy accumulations
in the rhizoma, or underground portion of the stem, as in the Man-
dioc or Cassava (Janipha Manihot) of tropical America, are per-
fectly innocuous, when freed from the poisonous juice by washing
and heating. The starch thus obtained is the Cassava, which, when
granulated, forms the Tapioca of commerce. The farinaceous albu-
men of the seed is also innocent, and the fixed oil which it frequently
contains is perfectly bland. But the oil procured by expression
abounds in the juices of the embryo and integuments of the seed, and
possesses more or less active properties. The seeds of Ricinus com-
munis yield the Castor oil: and those of Croton Tiglium, and some
other Indian species, yield the violently drastic Croton oil or Oil of

FIG. 1142. Flowering branch of Euphorbia corollata; the lobes of the involucre resem-
bling a corolla. 1143 Vertical section of an involucre (somewhat enlarged), showing a portion
of the staminate flowers surrounding the pistillate flower (a), which in fruit is raised on a
slender pedicel. 1144 One of the staniinnte flowers enlarged, with its bract, a : 6, the pedicel,
to which the single stamen, r, is attached by a joint ; there being no trace of floral envelopes.
1145 Cross-section of the 3-pistillate fruit. 1146 Vertical section of one of the pistils in fruit
((he two others having fallen away from the axis), and of the contained seed ; showing the em-
bryo leDgthwise. 1147. A seed.

KXOGKNOUS Ott DICOTYLEDONOUS PLANTS.

473

Tiglium. Some plants of the family are most virulent poisons; as,
for example, the Manchineal-tree of the West Indies (Ilippomane
Manicella), which is said even to destroy persons who sleep under its
shade ; and a drop of the juice blisters the hand. The hairs of some
species (such as our Cnidoscolus stimulosus) sting like Nettles. Box-
wood is invaluable to the wood-engraver. The purple dye called

Turnsole is from Crozophora tinctoria. Another most important
product of this order is Caoutchouc, which is yielded by various plants
of different families ; but the principal supply of the article (that of
Para, Demarara, and Surinam) is furnished by species of Siphonia.
910. Ol'd. EmpetracciE (Crowberry Family). Low, shrubby ever-
greens, with the aspect of Heaths ; the leaves crowded and acerose,

%^W

with small (dioecious or polygamous) flowers produced in the axils.
Calyx consisting of regular imbricated sepals, or represented by im-
bricated bracts. Stamens few : pollen of four grains coherent in
one, as in Heath. Ovary three- to nine-celled, with a single erect
ovule in each cell : style short or none : stigmas lobed and often
laciniated. Fruit a drupe, with from three to nine bony nucules.
Seeds albuminous; the radicle inferior. — Ex. Empetrum, Ceratiola,
Corema; unimportant plants. Probably no more than apetalous
Ericaceae ; but the stigmas are peculiar.

911. Ol'd. Ul'ticaceSD {Nettle Family), shrubs, or herbs, with stipules,
often with milky juice, and diclinous or polygamous, rarely perfect
flowers, furnished with a regular calyx ; which is free from the one-

FIG. 1148. Branch of Ceratiola ericoides in fruit. 1149. Magnified staminate flower, with
its bracts 1150. The two stamens, with an inner bract or sepal 1151 Magnified pistillate
flower, with its imbricated bracts. 1152. The pistil separate ; one of the cells laid open by a
vertical section, showing the erect ovule. 1153. Drupe with the persistent scales at the base.
1154 Transverse section of its endocarp, or two nucules, with the enclosed seed and embryo.
1155. Vertical section of the seed.

40*

474

ILLUSTRATIONS OF THE NATURAL ORDERS.

celled (sometimes two-celled) ovary and the always one-celled and
one-seeded fruit, but sometimes enclosing it. Stamens as many as
the lobes of the calyx and opposite them, or sometimes fewer. Em-
bryo large ; cotyledons mostly broad ; the radicle superior in the
fruit. Stipules often deciduous. A large and greatly diversified
order, comprising at least four well-marked suborders.

912. Sllbord. I'llMCes {Elm Family). Trees or shrubs, with a
watery juice, alternate rough leaves, perfect or merely polygamous
flowers, two styles or stigmas ; the ovary either one- or two-celled,
with one ovule suspended from the summit of each. Fruit either a
samara (Fig. 578), with a straight embryo and no albumen, as in

the Elm (Ulmus) ; or a drupe with a curved embryo and scanty
albumen, as in Celtis (Hackberry), the type of the tribe Celtide^e.
Timber-trees. The inner bark of the Slippery Elm is highly
charged with mucilage. Hackberries are edible.

913. Sllboi'd. ArtOCarpCEB {Bread-fruit Family) ; which are chiefly
tropical trees or shrubs with a milky or yellow juice ; the moncc-
cious or dioecious flowers mostly aggregated into fleshy heads, and

FIG. 1156 Flower of the Slippery Elm 1157 Calyx laid open and the ovary divided ver-
tically. 1153 Fruit, the cell laid open to show the single seed. 1159 The latter magnified.
11G0. Its embryo.

FIO. 1161 Uranch of Celtis Americana, in flower. 1162. Enlarged flower, divided verti.
eally. 1163. Drupe, the flesh divided to show the stone. 1163'. The coiled embryo.

EXOGENOUS OR DICOTYLEDONOUS ri.ANTS. 475

forming a multiple fruit, or else enclosed in a dry or succulent invo-
lucre. Styles or stigmas commonly two. Ovary ripening into an
achenium. Seeds with or without albumen. — Ex. Artocarpus (the
Bread-fruit), Morus (the Mulberry, Fig. 593-595), Madura (th&
Osage Orange), Ficus (the Fig, Fig. 590-592). The fruit is
often innocent and edible, at least when cooked ; while the milky
juice is more or less acrid or deleterious. It also abounds in Caout-
chouc ; much of winch is obtained from some South American trees of
this order, and from Fiscus elastica in Java. In one instance, how-
ever, the milky juice is perfectly innocent ; that of the famous Cow-
tree of South America, which yields a rich and wholesome milk.
One of the most virulent of poisons, the Bohon Upas, is the concrete
juice of Antiaris toxiearia of the Indian Archipelago. The Bread-
fruit is the fleshy receptacle and multiple fruit of Artocarpus.
Fustic is the wood of the South American Madura tinctoria ; the
wood of our own Madura or Osage Orange is used by the Western
Indians for bows. The resin called Gum Lac exudes and forms
small grains on the branches of the celebrated Banyan-tree (Ficus
Indica, Fig. 142).

914. Suboi'd. UrticefC (True Nettle Famihj) ; which are herbs in
colder countries, but often shrubs or trees in the tropics, with a
watery juice, often with stinging hairs; the monoecious or dioecious
flowers mostly loose, spicate, or panicled. Ovule orthotropous.
Ovary always one-celled, and style or stigma one ; the achenium
usually surrounded by a dry and membranous calyx. Embryo
straight, in fleshy albumen. — Ex. Urtica (the Nettle), &c. Innoc-
uous plants, except for the stinging hairs of many species. The
inner bark of Nettles yields very tough and slender fibres.

915. Sllbord. CaiinabinetE (Hemp Family). Annual erect herbs,
or perennial twining plants, with a watery juice and dioecious flow-
ers ; the staminate flowers racemose or panicled; the pistillate glom-
erate, or imbricated with bracts, and forming a kind of strobjle-like
anient ; their calyx one-leaved. Stigmas two. Ovary one-celled,
with an erect orthotropous ovule. Embryo coiled or bent : albumen
none. — Ex. Cannabis (the Hemp), Humulus (the Hop). Hops
are the catkins with large bracts ; the bitter and sedative principle
chiefly resides in the yellow grains that cohere to the scales and
cover the fruit. The leaves of Hemp, when grown in a hot climate,
are powerfully stimulant and narcotic, and are used in the East for
intoxication. The inner bark is used for cordage, &c.

476 ILLUSTRATIONS OF THE NATURAL ORDERS.

916. Ord. PlatiinacCfC (Plane-tree Family) consists of the single
genus Platanus (Plane-tree, Button-ball), with one Asiatic and one
or more North-American species : fine trees, with a watery juice,
and alternate palmately-lobed leaves, with sheathing stipules. Flow-
ers in globose amentaceous heads ; both kinds destitute of floral
envelopes. Fruit a one-seeded club-shaped little nut, the base fur-
nished with bristly hairs. Seed albuminous.

917. Ord. JllglaildacCcB (Walnut Family). Trees, with alternate
pinnated leaves, and no stipules. Flowers monoecious. Sterile
flowers in aments, with a membranous irregular calyx, and indefinite
stamens. Fertile flowers few, clustered, with the calyx adherent to
the incompletely two- to four-celled but one-ovuled ovary, the limb
small, three- to five-parted ; sometimes with as many small petals.
Ovule orthotropous. Fruit drupaceous ; the exocarp fibrous-fleshy
and coherent, or else coriaceous and dehiscent : endocarp bony.
Seed four-lobed, without albumen. Embryo oily : cotyledons cor-
rugate, two-cleft. — Ex. Juglans (Walnut, Butternut), Carya (Hick-
ory, Pecan, &c). — The greater part of the order is North Ameri-
can. The timber is valuable ; especially that of Black Walnut,
for cabinet-work, and that of Hickory, for its great elasticity and
strength. The young fruit is acrid : the seeds of several are de-
licious ; those of the Walnut abound in a drying oil.

918. Ord. Cupulifcra; (Oak Family). Trees or shrubs, with alter-
nate and simple straight-veined leaves, and deciduous stipules.
Flowers usually monoecious. Sterile flowers in aments, with a
scale-like or regular calyx, and the stamens one to three times the
number of its lobes. Fertile flowers solitary, two to three together,
or in clusters, furnished with an involucre which encloses the fruit
or forms a cupule at its base. Ovary adnate to the calyx, and
crowned by its minute or obsolete limb, two- to six-celled with one
or two pendulous ovules in each cell : but the fruit is a one-celled
and one-seeded nut (Fig. 57G). Seed without albumen. Embryo
with thick and fleshy cotyledons, which are sometimes coalescent. —
Ex. Quercus (the Oak), Fagus (the Beech), Corylus (the Hazel-
nut), Castanea (the Chestnut), &c. Some of the principal forest-
trees in northern temperate regions. The valuable timber and
edible nuts they furnish are too well known to need enumeration.
The astringent bark and leaves of the Oak abound in tannin, gallic
acid, and a bitter extractive called Quercine ; they are used in tan-
ning and dyeing. Quercib-on is obtained from the Quercus tine-

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

477

toria. Galls are swellings on the leafstalk?, &o., when wounded by
certain insects ; those of commerce are derived from Q. infectoria of
Asia Minor. Cork is the exterior corky layer of the bark of the
Spanish Quercus Suber.

919. Ol'd. Myi'icaceSB (Sioeet-Gale Family). Shrubs, with alter-
nate and simple aromatic resinous-dotted leaves, monoecious or dioc-
cious. Differs from the next principally by the one-celled ovary,
with a single erect orthotropous ovule, and a drupe-like nut. — Ex.
Myrica, Comptonia, the Sweet Fern. The drupes of M. cerifera
(our Candleberry or Bay berry) yield a natural wax.

920. Ol'd. BctlllaCCiE {Birch Family). Trees or shrubs, with al-
ternate and simple straight-veined leaves, and deciduous stipules.
Flowers monoecious ; those of both kinds in amenta (Fig. 312), and
commonly achlamydeous, placed three together in the axil of each
three-lobed bract. Stamens definite. Ovary two-celled, each cell
with one suspended ovule : styles or stigmas distinct. Fruit mem-
branaceous or samara-like, one-celled and one-seeded, forming with
the three-lobed bracts a kind of strobile. Albumen none. — Ex.
Betula (the Birch), Alnus (Alder). The bark is sometimes astrin-

FIG. 1164. Quercus Chinquapin in fruit : a, cluster of sterile aments 1165. A magnified
staminate flower. 1166. Transverse section of an ovary, showing the three cells with two
ovules in each. 1167. The immature seed, with the accompanying abortive ovule. 1168. The
nut (acorn), in its scaly involucre, or cupule. 1169. Vertical section of the same, and of the
Included seed and embrjo showing the thick cotyledons.

478

ILLUSTRATIONS OK THE NATURAL OKDKRS.

gent, and that of the Birch is aromatic. The peculiar odor of
Russia leather is said to he owing to a pyroligneous oil ohtaincd
from Betula alba, or White Birch.

1173

921. Ol'd. SaltcaceBB ( Willow Family). Trees or shrubs, with al-
ternate simple leaves, furnished with stipules. Flowers dioecious ;
both kinds in aments, and destitute of floral envelopes (achlamyde-
ous), one under each bract. Stamens two to several, sometimes
monadelphous. Ovary one-celled, many-ovuled ! Styles or stigmas
two, often two-cleft. Fruit a kind of follicle opening by two valves.
Seeds numerous, ascending, furnished with a silky coma ! Albu-
men none. — Ex. Salix (Willow, Fig. 415-419), and Populus (the
Poplar). Trees with light and soft wood : the slender, flexible
shoots of several "Willows are employed for wicker-work. The bark
is bitter and tonic, and contains a peculiar substance (Salicine),
which possesses febrifugal qualities. The buds of several Poplars
exude a fragrant balsamic resin.

FIO. 1170. Young ament of staminate flowers of a Birch (Betula fruticosa?). 1171. One of
the thne-lobed scales of the same, enlarged, showing the flowers (stamens) on the inner side.
1172. Ament of pistillate flowers. 1173. Branch in fruit. 1173' One of the scales with its
three flowers (pistils) seen from within. 1174 Magnified section of one of the two-celled pis-
tils, displaying the ovule suspended from the summit of each cell 1175. The pistils (with
their subtending bract) in a more advanced state. 117G. Magnified cross-section of one of the
ovaries. 1177 The mature fruit, with the cell divided vertically ; the single seed occupying
the cavity ; a mere trace of the other cell being visible. 1178. The seed removed. 1179. The
embryo.

EXOGENOUS OR DICOTYLEDONOUS PLANTS.

479

Subclass 2. Gymnospermous Exogenous Plants.

Ovules, and consequently the seeds, naked, that is, not enclosed in
an ovaiy (560) ; the carpel being represented either by an open
scale, as in Pines ; or by a more evident leaf, as in Cycas ; or else
wanting altogether, as in the Yew.

922. Ord. ConifcrO! (Pine Family). Trees or shrubs, with branch-
ing trunks, abounding in resinous juice (the wood chiefly consisting
of a tissue somewhat intermediate between ordinary woody iibre
and vessels, and marked with circular disks) ; the leaves mostly-

evergreen, scattered or fascicled, usually rigid and needle-shaped or

FIG. 1180. Carpellary scale of Cupressus sempervirens (the true Cypress), seen from with-
in, and showing the numerous orthotropous ovules that stand on its base 1181. Branch of
Abies Canadensis (Hemlock Spruce) with lateral staminate flowers, and a fertile strobile.
1182. Staminate anient, magnified. 1183 Carpellary scale of a fertile ament, with its bract.
1184, Similar fertile scale, more magnified and seen from within ; showing the two ovules ad-
herent to its base: one of them (the left) laid open. 11S5. The scale in front, nearly of the
natural size, its iuner surface occupied by the two seeds. 1186. Poljcotyledonous embryos of
Abies and Cypress. 1187. Vertical section of an embryo. 1188. Strobile of Taxodium di»-
tichum (Suborder Cupressinete).

480. ILLUSTRATIONS OF THE NATURAL ORDERS.

linear, entire. Flowers monoecious or dioecious, commonly amenta-
ceous. Staminatc flowers consisting of one or more (often mona-
delphous) stamens, destitute of calyx or corolla, arranged on a com-
mon rhachis so as to form a kind of loose anient. — The particular
structure of the flowers and fruit varies in the subordinate groups,
chiefly as follows : —

923. Sllbord. AbietineiB {Fir, or Pine Family proper). Fertile
aments formed of imbricated scales ; which are the flat and open
carpels, and bear a pair of ovules adherent to their base, with the
foramen turned downwards (Fig. 511). Scales subtended by bracts.
Fruit a strobile or cone (Fig. 596). Integument of the seed cori-
aceous or Avoody, more or less firmly adherent to the scale. Em-
bryo in the axis of fleshy albumen, with two to fifteen cotyledons.
Buds scaly.

924. Sllbord. Cliprcssincse {Cypress Family). Fertile aments of
few scales crowded on a short axis, or moue numerous and peltate,
not bracteate. Ovules one, two, or several, borne on the base of the
scale, erect (the foramen looking towards its apex, Fig. 516, 1180).
Fruit an indurated strobile, or sometimes fleshy and with the scales
concreted, forming a kind of drupe. Integument of the seed mem-
branous or bony. Cotyledons two or more. Anthers of several
parallel cells, placed under a shield-like connective. Buds naked.
— Ex. Cupressus (Cypress), Taxodium (American Cypress), Juni-
perus (Juniper, Red Cedar).

925. Sllbord. Taxinca! {Yew Family). Fertile flowers solitary,
terminal, consisting merely of an ovule, forming a drupaceous or nut-
like seed at maturity. There are, therefore, no strobiles and no
carpellary scales. Embryo with two cotyledons. Buds scaly. —
Ex. Ta'xus (the Yew), Torreya.

926. It is unnecessary to specify the important uses of this large
and characteristic family, which comprises the most important tim-
ber-trees of cold countries, and also furnishes resinous products of
great importance, such as turpentine, resin, pitch, tar, Canada bal-
sam, &c. The terebinthine Juniper-berries are the fruit of Juni-
perus communis. The Larch yields Venetian turpentine. The
powerful and rubefacient Oil of Savin is derived from J. Sabina of
Europe : for which our nearly allied J. Virginiana (Red Cedar)
may be substituted. The leaves of the Yew are narcotic and dele-
terious. The bark of Larch, and especially of the Hemlock-Spruce,
is used for tannin";.

EXOGENOUS OK DICOTYLEDONOUS PLANTS.

481

927. Orel. CycadilCCfC (Cyras Family). Tropical plants, with an
unbranched cylindrical trunk, increasing, like Palms, by a single
terminal bud ; the leaves pinnate and their segments more or less
rolled up from the apex (circulate) in vernation, in the manner of
Ferns. Flowers dioecious ; the staminate in a strobile or cone ; the
pistillate also in strobiles, or else (in Cycas) occupying contracted

and partly metamorphosed leaves ; the naked ovules borne on its
margins. — Ex. Cycas, Zamia. — A kind of Arrowroot is obtained
from these thickened stems, or caudexes, as from our dwarf Florida
species (the Coontie of the aborigines) ; and a coarse Sago from
the trunk of Cycas.

FTG. 1189 Zamia integrifolia (the Coontie of Florida). 1190. Section of the sterile ament.
1191. One of its scales detached, hearing scattered anthers 1192. Fertile anient, from which
a quarter-section is removed. 1193. A pistillate flower, consisting of two ovules pendent from
the thickened summit of the carpellary scale. 1194 A drupaceous seed, from which a part of
the pulpy outer portion, at the apex, is removed 1195 Vertical section through the seed (of
the natural size), showing the pulpy outer coat, the hard inner integument, the albumen, and
the embryo.

41

482 ILLUSTRATIONS OF THE NATURAL ORDERS.

Class II. Endogenous on Monocotyledonous Plants.

Stem not distinguishable into bark, pith, .and wood ; but the latter
consisting of bundles of fibres and vessels irregularly imbeded in
cellular tissue ; the rind firmly adherent ; no medullary rays, and
no appearance of concentric layers : increase in diameter effected
by the deposition of new fibrous bundles, which at their commence-
ment occupy the central part of the stem. Leaves seldom falling
off by an articulation, sheathing at the base, usually alternate, entire,
and with simple parallel veins (nerved). Floral envelopes when
present mostly in threes, never in fives ; the calyx and corolla most
commonly undistinguishable in texture and appearance. Embryo
with a single cotyledon ; or, if the second is present, it is much
smaller than the other, and alternate with it.

Conspectus of the Orders.

S! roup 1. Flowers on a spadix, furnished with a double and free perianth
(answering to calyx and corolla). Ovary one- to thrcc-ecllcil, with a single
ovule in cacli cell. Embryo in hard albumen. — Trees with unbranched
columnar trunks. Palmje.

Group 2. Flowers on a spadix ; with the perianth simple and free, or reduced
to a few scales, or commonly altogether wanting. — Chiefly herbs.

Terrestrial. Fruit nut-like, or comose, one-seeded. Typiiace^s.

Terrestrial, mostly with a spathc. Fruit baccate. Akacea:.
Aquatic (floating or immersed).

Flowers developed from the edge of tho floating frond. Lemnace,*:.

Flowers axillary or on a spadix. Naiad AC EiE.

Group 3. Flowers not spadiceous, furnished with a double and free perianth
(calyx and corolla). Ovaries several, distinct, or sometimes united. Aquat-
ic herbs. Alismaceje.

Gioup 4. Flowers with a simple or double perianth, which is adherent to tho
ovary, regular, developed from a spathc, polygamous or diclinous. Ovary
one-celled with parietal placental, or 3 - 9-cclled. Seeds destitute of albu.
men. — Aquatics. IIydrociiaridace.e.

Group 5. Flowers pcifect with the double or 6-merous perianth adherent to tho
ovary (or more or less free in some Hamuxloroccoo and Biomeliaccaj).
Seeds with albumen, except perhaps the very minute ones of Orchidaccai,
&c. Leaves parallcl-vcined.

ENDOGENOUS OR MONOCOTYLEDONOLS PLANTS. 483

Stamens gynandrotis, 1 or 2 fertile. Flower irregular. Orciiidace^e.

Stamens not gynandions. Flower irregular.
Fertile stamen 1, infeiior. Zisoiberace^

Fertile stamen 1, superior. Caxxace.e.

Fertile stamens mostly 5. the sixth abortive. Musacla:.

Stamens not gynandrous, regularly 3 or 6.
Anthers cxtrorsc. Stamens 3, before the sepals. Iridacicx.

Anthcis introrsc, when 3 before the inner perianth.

Anther-cells separated by a broad connective. Burmanxiace.*;.

Anther-cells approximate or joined.

Leaves not scurfy. Stems from bulbs. Amaryllidace^e.

Leaves scurfy or woolly. No bulbs.

Terrestrial. Stamens 3 or G. ILemodorace.t:.

Mostly epiphytes. Stamens G. Broueliaceje.

Group 6. Flowers dioecious, with a G-mcrous perianth adherent to the ovary.
Seeds with a minute embryo in hard albumen. Leaves ribbed and nctted-
veined, articulated with the stem. Dioscokeace;e.

Group 7. Flowers dioecious or pci feet ; the regular perianth free from the ovary.
Styles or sessile stigmas distinct. Embryo minute in hard albumen.
Leaves more or less nctted-vcincd. Smilace^e.

Group 8. Flowers perfect, not from a spathc, with the regular G-merous peri-
anth free from the ovary. Seeds anatropous, with albumen.
Perianth not glumaecous. Leaves parallel-veined.

Anthers introrsc. Styles united into one. Lii.iace^e.

Anthers cxtroisc. Styles mostly separate. Melaxtii acetic.

Perianth glumaecous. Styles united into one. Juncaceje.

Group 9. Flowers perfect, developed from a spathc, commonly somewhat ir-
regular, the 6-merous perianth free from the ovary. Seeds anatropous, with
albumen. Aquatics. ' • Poxtederiace^e.

Group 10. Flowers with a double or imbricated perianth, free from the ovary ;
the exterior divisions (sepals) herbaceous or glumaecous ; the inner (pet-
als) petaloid, free from the one- to three-celled ovary. Seeds 2, 3, or many,
orthotropous ; the embryo at the extremity of the albumen farthest from the
hilum.

Flowers perfect. Sepals herbaceous. Petals colored. Commelyxace/E.

Flowers perfect, capitate. Sepals and bracts glumaecous. Xyridace^:.

Flowers monoecious or dioecious, capitate. Eriocauloxaceje.

Group 11. Flowers imbricated with glumaecous bracts (glumes), and disposed
in spikclcts ; the proper perianth none or rudimentary. Ovary one-celled,
onc-ovuled. Seeds anatropous. Embryo at the extremity of the albumen
next the hilum.

Sheaths of the leaves closed. Glume or bract single. CtperacejE.

Sheaths open. Glumes mostly in pairs. Gkamixk.e.

484

ILLUSTRATIONS OF THE NATURAL ORDERS.

928. Ord. PalmiC (Palms). Chiefly trees, with unbranched cylin-
drical trunks growing by a terminal bud. Leaves large, clustered,
fan-shaped or pinnated, plaited in vernation. Flowers small, per-
fect or polygamous, mostly with a double (G-merous) perianth ; the
stamens usually as many as the petals and sepals together. Ovary
1 - 3-cellcd, with a single ovule in each cell. Fruit a drupe or berry.
Seeds with a cartilaginous albumen, often hollow ; the embryo placed
in a small separate cavity. — Ex. Palms, the most majestic race of
plants within the tropics, and of the highest value to mankind, are
scarcely found beyond the limits of these favored regions. The
Date-tree (Phoenix dactylifera, the leaves of which are the Palms
of Scripture), a native of Northern Africa, endures the climate of
the opposite shores of the Mediterranean: while in the New World,
CImmajrops Palmetto (Fig. 184), the only arborescent species of the
United States, and one or two low Palms with a creeping caudex
(Dwarf Palmetto), extend from Florida to North Carolina. Palms
afford food and raiment, wine, oil, wax, flour, sugar, salt, thread,
weapons, utensils, and habitations. The Cocoanut (Cocos nucifera)
is perhaps the most important, as well as the most widely diffused
species. Besides its well-known fruit, and the beverage it contains,

1136 1158 1193 1-03

the hard trunks are employed in the construction of huts ; the ter-
minal bud (as in our Palmetto and other Cabbage Palms) is a deli-
cious article of food ; the leaves are used for thatching, for making

FIO 119G Branch of the inflorescence of Chamffirops hystrix (Blue Palmetto). 1197 A
sterile flower. 1198 Perfect flower, with the calyx and corolla removed. 1199 Same, with
three of the stamens removed, so as more distinctly to show the three somewhat united carpels.
12C0 One of the carpels enlarged, seen laterally. 1201 Same, with a section of its inner face,
Showing the ovule or joung seed. 1202. Vertical section of a young cocoanut, showing the
hollow albumen ; and also the small embryo in a separate little cavity. 1203 Section of a
Falm-sttta.

ENDOGENOUS OR MOXOCOTYLEDONOUS TLANTS. 485

hats, baskets, mats, fences, for torches, and for writing upon ; the
stalk and midrib for oars ; their ashes yield abundance of potash ;
the juice of the flowers and stems (replete with sugar, which is
sometimes separated under the name of Jagery) is fermented into a
kind of wine, or distilled into ^4>rflc£; from its spathes (as from
some other Palms), when wounded, flows a grateful laxative bever-
age, known in India by the name of Toddy ; the rind of the fruit is
used for culinary vessels ; its tough, fibrous, outer portion is made
into very strong cordage (Coir rope) ; and an excellent fixed oil is
copiously expressed from the kernel. Sago is procured from the
trunks of many Palms, but chiefly from species of Sagus of Eastern
India. Canes and Rattans are the slender, often prostrate, steins of
species of Calamus. — The Phytelephas, or so-called Ivory Palm,
of Central America, the seeds of which are the Vegetable Ivory now
so commonly used by the turner, in place of ivory, for small articles,
is not a genuine Palm, having polygamo-dioccious flowers with a
rudimentary perianth, or none at all, &c. It is proposed as the type
of an order (Phytelephanteje) ; but may for the present be ap-
pended to the Palms ; between which and the succeeding orders
stands the

929. Ol'd. PandanacCtC ; tropical arborescent plants, of Palm-like
port, but their simplified diclinous flowers destitute of a perianth, the
one-celled ovary many-ovuled. The seeds of Pandanus (the Screw-
Pine, Fig. 140), &c. are eatable. From the young leaves of Car-
ludovica the famous Panama hats are braided.

930. Ol'd. TypliacetC {the Cat-tail Family) consists of two genera ;
namely, Typha (the Cat-tail), and Sparganium (Bur-reed), of no
important use. They are spadiceous plants with excessively re-
duced flowers, having no perianth.

931. Ol'd. AracctB (Arum Family). Herbs, with a fleshy corm or
rhizoma, often .shrubby or climbing plants in the tropics; the leaves
sometimes compound or divided, commonly netted-veined. Flowers
mostly on a spadix (often naked at the extremity), usually surround-
ed by a spat he or hood (Fig. 313, 314). Flowers commonly monoe-
cious, and destitute of envelopes, or with a single perianth. Ovary
one- to several-celled, with one or more ovules. Fruit a berry.
Seeds with or without albumen. — Ex. Arum, Calla, Symplocarpus
(Skunk-Cabbage), Orontium, Acorus (Sweet Flag) : the three latter
bear flowers furnished with a perianth. — All are endowed with an
acrid volatile principle, which is merely pungent and aromatic ill

41*

486

ILLUSTRATIONS OF THE NATURAL ORDERS.

Sweet Flag (Acorus Calamus), but extremely sharp in Arum,
Indian Turnip, &c. The acrid principle of these plants is volatile,
and is dissipated by heat or in drying. "When cooked, their farina-
ceous corms are 'eatable. That of Taro of the South Sea Islands,
and some other species of Colocasia, are important articles of food.
Symplocarpus fectida exhales a strong odor, very like that of the

skunk, whence, as it has large and roundish leaves in a radical clus-
ter, it is called Skunk Cabbage. The roots have been used in medi-
cine as an antispasmodic.

932. Ol'il. LeillliacCiB (Duckweed Family), consisting chiefly of
Lemna (Duckweed or Water Flax-seed) ; floating plants, with their
roots (if any) arising from the bottom of a flat frond, and hanging
loose in the water ; their flowers produced from the margin of the
frond, bursting through a membranous spathe ; the sterile, of one or

FIG 1204 Young leaf, and 1205, spathes and flowers, of Symplocarpus fnetida 120G A
separate flower when joung. 1207 A detached sepal and stamen seou fiom within 1208. An
anther seen from th« front 1209. The spadix or collective head in fruit ; a quarter-section
lemoVGit. showing sections of the immersed seeds 1210 A seed detached, of the natural size
1211 Section of the seed, with its large globular embryo and plumule . in this plant there ia
do albumen.

ENDOGENOUS OR MOXOCOTVLKDONOU3 PLANTS.

487

two stamens; the fertile, of a one-celled ovary; in fruit a utricle
they are a kind of minute and greatly reduced Araceie, a>nnectin£
that order with the next.

933. Ord. NaiatlnCCfC (Pondweed Family). Water-plants, with
cellular leaves, and sheathing stipules or hascs : the flowers incon-
spicuous, sometimes perfect. Perianth simple and scale-like, or
none. Stamens definite. Ovaries solitary, or two to four and dis-
tinct, one-seeded. Albumen none. Embryo straight or curved. —
Ex. Potamogeton (Pondweed), Najas, Ruppia, 'Zostera ; the two
latter in salt or brackish water.

934. Ol'd. AlismacctB ( Water-Plantain Family). Marsh herbs,
with the leaves and scapes usually arising from a creeping rhizoma ;
the former either linear, or bearing a flat limb, which is ribbed or
nerved, but the veinlets commonly reticulated. Flowers regular,
perfect or polygamous, mostly in racemes or panicles, not on a spa-
dix. Perianth double, the three petals commonly different from the
sepals, so as evidently to represent a calyx aiid a corolla. Seeds soli-
tary in each carpel or cell, straight or curved, destitute of albumen.
— Ex. Alisma (Water-Plantain), Sagittaria (Arrowhead); belong-
ing to the proper Alisma Family, which has the seed (and conse-

FIG. 1212. Whole plnnt of T.cmna minor, mngnified, bearing a stnminatc monandrous flow-
er 1213. An individual with a diandrous perfect flower ; which at 1214 is seen separate, with
its spathe. highly magnified. 1215. Flower of Xemna gibba, much magnified 1216 Vertical
highly magnified section of the pistil and the containc-1 ovule of Lemna minor 1217 The
fruit, and 1218, its section, showing the seed. 1219. Section through the highly magnified
eeed and large embryo.

488

ILLUSTRATIONS OF THE NATURAL ORDERS.

quently ilic embryo) curved or doubled upon itself. Triglocliin and
Sckeuchzeria chiefly constitute the suborder Juncaginejk ; where
the seed and embryo are straight, and the petals (if present) are
greenish like the calyx. Slightly acrid plants, and some of them
astringent.

93o. Orth Blltomacea\ represented by Butomus, the Flowering-
Rush of Europe, and three small tropical genera, is a form of the
last with many ovules attached to the -whole face of the carpels :
these are separate or combined. Some have a milky juice.

93G. Ol'll. IlydrOCharidaCClB {Froc/s-bit Family) consists of a fe^
aquatic herbs, with dioecious or polygamous regular flowers on scape'
like peduncles from a spathe, and simple or double floral envelopes,
which in the fertile flowers are united in a tube, and adnate to the
1 — G-celled ovary, more commonly one-celled with three parietal
placentae. Seeds numerous, without albumen. — Ex. Limnobium,
Vallisneria, Anacharis.

937. Ord. Orcllidacea? ( Orchis Family). Herbs, of varied aspect

-wl form ; distinguished from the other orders with an adnate ovary,

•td from all other plants, by their irregular flowers, with a perianth

FIG 1220. Raceme or spike of Triglochin palustrc. 1221. Enlarged flower 1222 A petal
and stamen. 12C3. The club-shaped capsule. 1224. A magnified seed, exhibiting the rhaphe
and rhalaza. 1225 Embryo of the same. 1226. Vertical section of the same, bringing the
plumule to view. 1227. Cross-section (more magnified), showing the cotyledon wrapped
around the plumule.

FIG. 1228. Leaf, and 1229, flower, of Alisma Plantago 1C30. More enlarged flower, with
'•e petals removed. 1231 Carpel, with the ovary divided, showing t'.ie doubled ovule. 1C31.
.ertiral section of the germinating seed of Alisma Damasonium ; o, the cotyledon ; 4, the plu-
mule ; c, the protruding radicle.

ENDOGENOUS OR MONOCOTYLKDONOUS TLANTS.

489

of six parts ; their single fertile stiimcn (or in Cypripedium their
two stamens) coherent with the style (composing the column) ; their
pollen usually combined into two or more granular or waxy masses
(pollinia) ; the ovary one-celled, with three parietal placentae,

covered with numerous minute seeds. — Ex. Orchis, Cypripedium
(Ladies' Slipper), Arethusa, &c. In the tropics many are Epiphytes
(149, Fig. 144). Many are cultivated for their beauty and singu-
larity. The luberiferous roots are often filled with a very dense
mucilaginous or glutinous substance (as those of our Aplectrum,
thence called Putty-root). Of this nature is the Salep of commerce,
the produce of some unascertained species of Middle Asia. The
fragrant Vanilla is the fleshy fruit of Vanilla planifolia and other
tropical American species. The roots of Cypripedium are used as
a substitute for Valerian.

938. Ord. ZingiberaccDB ( Ginger Family) consists of some mostly
showy tropical aromatic herbs, the nerves of their leaves diverging

FIO. 1233. Orchis spectabilis : a, a separate flower. 1234. Column (somewhat magnified),
from which the other parts are cut away : the two anther-cells opening and showing the pollen-
musses. 1235. Magnified pollen-mass, with its stalk. 1236. Arethusa bulbosa. 1237 The
column, enlarged : the anther terminal and opening by a lid. 123S. Magnified anther, witfc
the lid removed, showing the two pollen-masses in each cell.

490 ILLUSTRATIONS OF THIi NATURAL ORDERS.

from a midrib ; the adnate perianth irregular and triple (having «i
corolla of two series as well as a calyx) ; fertile stamen one, on the
anterior side of the flower, free ; the fruit a three-celled capsule or
berry ; the seeds several : with the embryo in a little sac at one
extremity of the farinaceous albumen. — There are, in fact, six
stamens in the andrcecium, the three exterior petaloid and forming
the so-called inner corolla, and two of the inner verticel are sterile.
— Their properties and economical uses are well represented by the
pungent aromatic rootstock of Ginger (Zingiber officinale), Galin-
yale (Alpinia Galanga, &c), the seeds of Cardamon, &c. The same
cordial qualities in lesser degree exist in the roots of Curcuma
longa, &c. which furnish the coloring matter called Turmeric ; while
other species yield starch, like the closely allied

939. Ord. CannacCOO (Arrowroot Family), which aho consists of trop-
ical plants, differs from the preceding chiefly in the want of aroma,
and in having the single fertile stamen posterior, with a one-celled
anther. — Ex. Maranta arundinacea, which yields the Arrowroot of
the "West Indies ; the tubers of which are filled with starch.

940. Ol'd. Miisacea) (Banana Family). Tropical plants, of which
the Banana and Plantain are the type ; distinguished by their
simple perianth and five or six perfect stamens. The fruit is an
important staple of food in the tropics ; the gigantic leaves are used
in thatching ; and the fibres of Musa textilis yield Manilla hemp, as
well as a finer fibre from which some of the most delicate India mus-
lins are made.

941. Ord. BurmanniaceO! consists of small, mostly tropical, annual
herbs, commonly with a one-celled ovary and three parietal placenta?,
(but in several the ovary is three-celled) ; differing from Orchidacea;
by their regular flowers with three stamens ; and from Iridacere by
the position of these before the inner divisions of the perianth, the
introrse anthers, &c. — Ex. Burmannia and Apteria, of the South-
ern States.

942. Ord. Iridaccffi (Iris Family). Perennial herbs ; the flower-
stems springing from bulbs, conns, or rhizomas, rarely with fibrous
roots, mostly with equitant leaves. Flowers regular or irregular,
showy, often springing from a spathe. Perianth with the tube ad-
herent to the three-celled ovary, and usually elongated above it; the
limb six-parted, in two series. Stamens three, distinct or monadel-
phous ; the anthers extrorsc ! Stigmas three, dilated or petaloid !
Seeds with hard albumen. — Ex. Iris, Crocus. . The rootstocks,

ENDOGENOUS OS MONOCOTYLEDONOUS rLANTS.

491

corms, &c. contain starch, with some volatile acrid matter. Those
of Iris cristata are very pungent ; tho.se of I. versicolor, &c. are

drastic. Orris-root is the dried rhizoma of Iris florentina, of South-
ern Europe. The true Saffron consists of the dried orange-colored
stigmas of Crocus sativus.

943. Ol'd. AmarjilidaceaJ (Amaryllis Family). Bulbous plants
(sometimes with fibrous roots), bearing showy flowers mostly on
scapes. Perianth regular, or nearly so ; the tube adherent to the
ovary, and often produced above it, six-parted. Stamens six, dis-
tinct, with introrse anthers. Stigma undivided or three-lobed.
Fruit a three-celled capsule or berry. Seeds with fleshy albumen.
— Ex. Amaryllis, Narcissus, Crinum, &c. ; mostly ornamental plants.
The bulbs acrid, emetic, &c. : those of Ilamianthus (with whose juice
the Hottentots poison their arrows) are extremely venomous. The
fermented juice of Agave is the intoxicating Pulque of the Mexicans.
Hypoxys, which has been taken as the type of an order, may prop-
erly be referred to this family.

FIG 1230. Iris cristata. 1240. The summit of the style, petaloid stigmns, and
1241 Vertical section of the ovary (the equitant leaves cut away) and long tube of the peri-
anth. 1242. Cross-section of the pod. 1243. Seed. 1244. Enlarged section of the same, show-
iug the embryo, &o.

492 ILLUSTRATIONS OF THE NATURAL ORDERS.

944." Oi'll. BromdincCiT (Pine-Apple Family) consists of American
and chiefly tropical plants ; with rigid and dry channelled leaves,
often with a scurfy surface, a mostly adnate perianth of three sepals
and three petals, and six or more stamens ; the seeds with mealy
albumen. — Ex. Ananassa, the Pine-Apple ; the fine fruit of which
is formed by the consolidation of the imperfect flowers, bracts, and
receptacle into a succulent mass. Tillandsia, the Black Moss or
Long Moss (which, like most Bromelias, grows on the trunks and
branches of trees in the warmer and humid parts of America), has
the ovary free from the perianth.

945. 0"d. llffiinodoraCCffi {Bloodwort Family) is composed of peren-
nial herbs, with tibrous roots, equitant or ensiform leaves ; which,
with the stems and flowers, are commonly densely clothed with
woolly hairs or scurf. Perianth with the tube either nearly free
from, or commonly adherent to, the three-celled ovary ; the limb
six-cleft, regular. Stamens six, or only three, with introrse anthers.
Style single, the stigma standing over the dissepiments of the ovary.
Embryo in cartilaginous albumen. — Ex. Lachnanthes (Red-Root),
Lophiola. — Some have a red juice. The roots arc astringent and
tonic, especially in Aletris.

946. Ol'd. DiosCOreaccrB {Yam Family) consists of a few twining
plants, with large tuberous roots or knotted rootstocks ; distinguished
among Endogens by their ribbed and netted-veined leaves, with dis-
tinct petioles, and by their inconspicuous dioecious flowers, with the
perianth in the pistillate flowers adherent to the ovary ; the limb
six-cleft in two series. Stamens six. Ovary three-celled, with only
one or two ovules in each cell : styles nearly distinct. Fruit often
a three-winged capsule. Albumen cartilaginous. — Ex. Dioscorea.
The tubers of one or or more species, filled with starch and mucilage
(but more or less acrid until cooked), are Tarns, an important article
of food in tropical countries.

947. Ol*(l. SlllilaceSC (Smilax Family) is also remarkable among
Endogens for netted-veined leaves. It consists both of herbs and of
shrubby plants climbing by tendrils ; the perianth is free from the
ovary ; the mostly three styles or sessile stigmas are entirely dis-
tinct ; the anthers are introrse ; and the fruit is a berry. Embryo
minute, in hard albumen. — In the Trite Smilax Family, the flowers
are dioecious and axillary ; the six divisions of the perianth are
alike ; the anthers are one-celled, and the few seeds are orthotropous
and pendulous. They are mostly shrubby and alternate-leaved

ENDOGENOUS OR MONOCOTYLEDONOUS PLANTS.

493

plant?. Ex. Smilax (Greenbrier, &c.) ; far the most important
species is S officinalis of tropical America, the rootstocks of which
are the officinal Sarsaparilla.

948. Sllboi'd. Trilliaccrc ( Trillium Family) consists of low
herbs, with whorletl leaves and per-
fect flowers, which in the largest
genus, Trillium, have a green calyx
and a colored corolla ; the anthers
are two-celled ; the seeds anatropous
and rather numerous. — The short
rootstock of Trillium (Fig. 1G9),
called Birthroot, has a place in the
popular materia medica ; but it is
doubtful if it really possesses any-
useful properties.

949. On!. LiliacCJE {Lily Family). Herbs,
with the flower-stems springing from bulb=,
tubers, or with fibrous or fascicled roots.
Leaves simple, sheathing or clasping at the
base, parallel-veined. Flowers regular, per-
fect. Perianth colored, mostly of six parts,
or six-cleft. Stamens six: anthers introrse. 12'6

Ovary free, three-celled: the styles united into one. Fruit capsular
or baccate, with several or numerous seeds in each cell. Albumen
fleshy. — This large and widely diffused order comprises a great
variety of form; : the. Lily, Dog-tooth Violet, and Tulip represent one
division ; the Tubero?e, a second ; the Aloe and Yucca, a third ;
the Hyacinth, the Onion, Leek, and Garlic (Allium), and the As.
phodel, a fourth ; the Asparagus, Lily of the Valley, and Solomon s
Seal, a fifth, which is nearly allied to the order Smilacea?. Acrid
and often bitter principles prevail in the order, and are most concen-
trated in the bulbs, &c, which abound in starchy or mucilaginous
matter, and are often edible when cooked. Squills are the bulbs of
Scilla maritima of the South of Europe. Aloes is the acrid and
bitter inspissated juice of the succulent leaves of species of Aloe.
The original Dragon s-blood was derived from the juice of the fa-
mous Dragon-tree (Dracama Draco) of the East. — The leaves
of Phormium-tenax yield the Neio Zealand hemp, one of the

FIG. 1245 A flower of Trillium erectum ; a front riew. 1246 A diagram of the i

42

494

ILLUSTRATIONS OF THE NATURAL ORDERS-

strongest vegetable fibres known. Many are the ornaments of oar
gardens and conservatories.

950. Ord. MclantliacCtt (Colchicum Family). Herbs, with bulbs,
corms, or fasciculated roots. Perianth regular, in a double series ;
the -.sepals and petals cither distinct, or united below into a tube.
Stamens six, with extrorse anthers (except in Toneldia and Pleea).
Ovary free, three-celled, several-seeded : styles distinct. Albumes,
fleshy. The true Melanthacea?, or

951. Sllbord. McIanthieSB have a mostly septicidal capsule and a
marcescent or persistent perianth. — Ex. Colchicum has a perianth
with a long tube, arising from a subterranean ovary ; it is also re-
markable for flowering in the autumn, when it is leafless, ripening
its fruit and producing its leaves the following spring. In most of
the order, the leaves of the perianth are uncombined ; as in Yera*
trum (White Hellebore), Helonias, &c. Acrid and drastic poison-
ous plants, with more or less narcotic qualities ; chiefly due to a
peculiar alkaloid principle, named Veratria, which is largely ex-

FTG. 1247. Erythronium Americatium (Dog-tooth Violet, Adder's-tongue) 1248. The
bulb 1249. Tei-ianta laid open, with the stamens. 1250. The Pistil. 1251 Cross-sectioa
of the capsule.

ENDOGENOUS OR MONOCOTYLKDONOUS PLANTS.

493

tracted from the seeds of Sabadilla, or Cebadilla; the produce of
Schccnocaulon officinale, &c. of the Mexican Andes. The seeds and
the corms of Colchicum are used in medicine.

952. Sllbord. UvularieSB (Bellwort Family) has a few-seeded loculi-
cidal capsule or berry, more or less united styles, and a deciduous
perianth ; the stems from rootstocks. — Ex. Uvularia.

953. Ord. JllllCaceae {Rush Family). Herbaceous, mostly grass-
like plants, often leafless ; the small glumaceous flowers in clusters,
cymes, or heads. Perianth mostly dry, greenish or brownish, of six
leaves (sepals and petals) in two series. Stamens six, or three :
anthers introrse. Ovary free, three-celled, or one-celled from the
placenta? not reaching the axis ; their styles united into one : stig-
mas three. Capsule three-valved, few- or many-seeded. Albumen
fleshy. — Ex. Juncus (Rush).

954. Ord. roiltedei'iaccae (Picker -el-ioeed Family) comprises a few
aquatic plants, with the flowers, either solitary or spicate, arising
from a spathe or from a fissure of the petiole ; the six-cleft and
colored perianth persistent and withering, often adherent to the base
of the three-celled ovary ; the stamens three, and inserted on the

FIG. 1252. Colchicum autumnale ; a flowering plant. 1253 Perianth laid open. 125*.
Pistil, with the long distinct st/le3 1251 Leafy stem aid fruit (capsule opening by eepti-
cidul dehiscence). 1258. Capsule di . idei truuiveraeiy. 1-57. Sectiou of a seed, and a sep-
arate embryo*

49G ILLU3TRATIOX3 OV TIIK NATURAL OUDKRS.

throat of the perianth, or six, and unequal in situation. Ovules
anatropous, numerous ; but the fruit often one-celled and one-seeded.
— Ex. Pontederia (Pickerel-weed), Ileteranthera, &c

955. OrJ. CominelyiiaCDiE (Spidenoort Family), with usually sheath-
ing leaves ; distinguished from other Endogens (except Alismacea)
and Trillium) by the manifest distinction between the calyx and
corolla ; the former of three herbaceous sepals ; the latter of as
many delicate colored petals. Stamens six, or fewer : anthers with
two separated cells : filaments often clothed with jointed hairs,
hypogynous. Ovary two- or three-celled: styles united into one.
Capsule few-seeded, loculicidal. Seeds orthotropous. Embryo
small, 'pulley-shaped, partly sunk in the apex of the albumen. —
Ex. Commelyna, Tradescantia (Spiderwort) Mucilaginous plants.

95G. Ord. XyridaceaC. Low, rush-like plants; with ensiform, grassy
or filiform radical leaves, sheathing the base of a simple scape,
which bears a head of flowers at the apex, imbricated with bracts.
Calyx of three glumaceous sepals, caducous. Petals three, with
claws, more or less united into a monopetalous tube. Stamens six,
inserted on the corolla ; three of them bearing extrorse anthers,
the others mere sterile filaments. Ovary one-celled, with three
parietal placentae, or three-celled : styles partly united : stigmas
lobed. Capsule many-seeded. Seeds orthotropous, albuminous. —
Ex.. Xyris (Yellow-eyed Grass).

957. Onl. El'iocauloiiacCiC (Pipewort Family). Aquatic or marsh
herbs, with much the structure of the preceding; their leaves cel-
lular or fleshy ; their minute flowers (monoecious or dioecious)
crowded, along with scales or hairs, into a very compact head : the
corolla less petaloid than in Xyridaeerc ; the six stamens often all
perfect ; the ovules and seeds solitary in each cell. — Ex. Eriocaulon.

958. Ord. RestiaccaJ consists of South African and Australian
Push-like plants, with the aspect of Cyperacese, but with one-celled
anthers and orthotropous seeds.

959. Onl. CypcraccSB {Sedge Family). Stems (culms) usually
solid, crcspiio-e. Sheaths of the leaves closed. Flowers one in the
axil of each glumaceous bract. Perianth none, or a few bristles.
Stamens mostly three, hypogynous. Styles two or three, more or
less united. Fruit an achenium. Embryo snydl, at the extremity
of the seed next the hilum. — Ex. Cyperus, Seirpus, Carex (Sedges).
The herbage is little eaten by cattle. Some Clubrushes are used
for making mats, chair-bottoms, &c. The papyrus of the Egyptians

ENDOGENOUS OU MONOCOTYEEDONOUS PLANTS.

497

was made from the stems of Cyperas Papyrus. Tlic tubers of
C. esculentus arc sweet and edible, but arc too small to be of much
value for food.

9G0. Oi'tl. BrominCSE ( Grass Family). Stems (culms) cylindrical,
mostly hollow, and closed at the nodes. Sheaths of the leaves split
or open. Flowers in little spikelets, consisting of two-ranked imbri-
cated bracts ; of which the exterior are called glumes, and the two
that immediately enclose each flower, palece. Perianth none, or in
the form of very small and membranous hypogynous scales, from
one to three in number, distinct or united (termed squamulcs, squa-
mellce, or lodiculce). Stamens commonly three : anthers versatile.
Styles or stigmas two ; the latter feathery. Fruit a caryopsis.
Embryo situated on the outside of the farinaceous albumen, next the

FIG 1258. Srirpus triqueter. with its cluster of spikelets. 1259 A separate flower, en-
larged showing its rudimentary perianth of a few denti ulatc bristles, its three stamens, and
pistil with a three-cleft style : a, section of the seed, showing the minute embryo. 12G0. Ca-
rex Care, ana, reduced in size (flowers monoecious, the two kinds in diTorent spike?). 12C1.
Stem, with the stominato ar.d upper pistillate spike, of the size of nature. 12C2. A scale of
the Stan: innte spike, v.ith tie flower (consisting merely of three st:-.iv.c::s) in it* nx'l. 17G3.
Jlagi.i.led pistillate flower, with its scale or bract : the ovary enclosed in a kir.d of sac (pfn's'J-
tiium), formed by the union of two bractlets. 1CG4. Cross-section of the perigyniuin ; with
the pistil, /', removed. 1ZGJ. Vertical section of the achuuiuui, showing the seed.

42*

498

ILLUSTRATIONS OF THE NATURAL ORDERS.

hilum (Fig. 126-128, G22 - G24). — i2!r. Agrostfa, Phleum, Poa,
Festuca, which arc the principal meadow and pasture grasses : Ory-
za (Rice), Zea (Maize), Avena (the Oat), Triticum (Wheat), Sccalc
(Rye), llordeum (Barley), are the chief cereal plants, cultivated for
their farinaceous seeds. This universally diffused order is one of
the largest of the vegetable kingdom, and doubtless the mo^t impor-
tant ; the floury albumen of the seeds and the nutritious herbage
constituting the chief support of man and the herbivorous animals.
No unwholesome properties are known in the family except in the
grain of Darnel, which is deleterious. Ergot, or Spurred Rye, is
no exception, being a morbid growth, caused by a parasitic fungus.
The stems of grasses frequently contain sugar in considerable quan-
tity (especially when they are solid) ; as in Maize, the sweet variety
of Sorghum vulgare, or Broom-Corn, and in Sugar-Cane (Saccharum
officinarum), which affords the principal supply of this article.

\M

TIG 1260. Or.c-flowered spikelet or loensta of Alopecurus, with the glumes fcparated.
1267. Same with the glumes removed : an aunt on the back of the outer palea. 12G8 Onc-
flawered spikelet of an Agrostis 1269. Pistil of a Grass, showing the two feathery stigmas,
and the two h} pogynous sc;iles or squamulse, larger than usual (representing the perianth).
1270. Two-flowered spikelet of an Avcna ; with the glumes spreading. 1271 Oce of the flow-
ers with its palea; ; the exterior pointed, with two bristles or cusps at the apex, and with a
bent awn on the back 1272. Many-flowered spikelet of Glyceria lluitans. 1273 An enlarged
separate flower of the same, seen from within, showing the inner paleae, &c 1274. The fruit
(ear) opsis) of the Wheat, with an oblique section thtonsh the integuments of the embryo,
which is exterior to the albumen. 1275 Detached magnified embr.o : n. the imperfect cotyle-
don ; 6, the first leaf of the plumule; c the second leaf of the plumule ; </, the radicle. 127G
The can opsis of Ilordenm (Barley;. 1277. A cross-section 1278 A vertical section, show-
ing the external embryo at the base 1279 Magnified detached embryo, with its broad cotyle-
don and the plumule. 12S0. Moie magnified vertical section of the same: a, the plumule ; b,
the radicle.

CRYPTOGAllOUS OR FLOWEKLESS PLANTS.

499

Series II. Cryftoga:\ious or Feowerless Plants.

Plants destitute of proper flowers (stamens and pistils), and
propagated by spores instead of seeds.

Class III. Aceogexous Plants.*

Vegetables with a distinct axis, growing from the apex, with no
provision for subsequent increase in diameter (containing woody and
vascular tissue), and usually with distinct foliage.

9G1. Ord. EqilisetilCeiC {Horsetail Family). Leafless plants ; with
striated, jointed, simple or ]C82 KS1

branched stems (containing ducts
and some spiral vessels), which
are hollow and closed at the
joints ; each joint terminating in
a toothed sheath, which surrounds
the base of the one above jt. In-
florescence consisting of peltate
scales crowded in a terminal
spike, or kind of strobile : each
with several thecce attached to its
lower surface, longitudinally de-
hiscent. Spores numerous, with
four elastic club-shaped bodies
(of unknown use), wrapped
around them when moist, 'of
spreading when dry. — Ex. Equi-
setmn. The epidermis of Equi-
setum hyemale (the well-known
Scouring Rush) contains so much
silex that it is used for polishing.

* For illustrations of Classes III. and IV. sec tho plates of Manual of the
Botany of the Northern United States.

FIG 1981. Summit of the stem of Equisetum sylvaticum. 1282. Part of the axis of the
fructification, with some of the fruit-bearing org ins, shown magnified in Fig 12S3, a view from
underneath. 1281. A separate theca, or spore-case, more magnified. liSo, 12S0. Spores, with,
the club-shaped appendages more magnified.

500

ILLUSTRATIONS OF THE NATUItlx ORDEBS.

962. Ord. Filiccs (Ferns). Leafy plants ; with the leaver (fronds)
spirally rolled up or circulate in vernation (except in one suborder),
usually rising from prostrate or subterranean rootstocks, or in tree-
Ferns from an erect arborescent trunk (Fig. 100), and bearing on
the veins of their lower surface, or along the margins, the simple
fructification, which consists of one-celled spore-cases (thecce or spo-
rangia), opening in various ways, and discharging the numerous

minute spores. The stalk or petiole of the frond is termed a stipe.
— There are four principal suborders, viz.: —

FTCJ 1287. Cnmptosorns rhizophyllus (Walking Fern); the fronds rooting, as they fre-
quently do, at the apex ; the sori occupying the reticulated veins on the back. 128S Division
(piuuula) of a frond of Aspidium Goldianum ; the roundish sori attached to the simple veins,
and covered with an indusium, which is fastened in the centre, and opens all around the mar-
gin. 1289. Magni£ed sporangium of this division of Ferns, with its stalk, and elastic ring
partly surrounding it ; which, tending to straighten itself when dry, tears open the sporangium,
shedding the minute spores (1290). 1291. Schizacapusilla of about the natural size, with simplo
and slender radical leaves ; the contracted fertile frond pinnate. 1292. A division (pinna) of
the fertile frond, m»gnified, showing the sessile sporangia occupying its lower surface. 1293.
Ono of the sporangia more magnified ; they have no proper ring, and open by a longitudinal
cleft 1294. Ophioglossum vulgatum (Adder's-tongue) ; the sporangia forming a two-ranked
spike on a transformed and contracted frond : a, portion of the spiko enlarged, showing the co-
riaceous sporangia, destitute of a ring and opeuiug transversely.

CRYPTOGAMOUS OR FLOWKKLESS PLANTS.

501

9G3. Subord. rolypodinCu". Sporangia collected in dots, lines, ov
variously shaped clusters (so?-i ov fruit-dots) on the back or margins
of the frond or its divisions, or rarely covering the whole surface,
stalked, cellular-reticulated, the stalk running into a vertical incom-
plete ring, which by straightening at maturity ruptures the sporan-
gium transversely on the inner side, discharging the spores. Fruit-
dots often covered, at least when young, by a membrane called the
involucre, or more properly the indusium.

964. Subord. HyniCHOphyllCiC. Sporangia borne on a vein extended
beyond the margin of the frond into a setiform receptacle, sessile, and
surrounded by a horizontal complete ring ; otherwise as in the last.
— Ex. Hymenophyllum, TYichomanes. Ferns of very delicate
texture, chiefly tropical.

9 Go. Subord. OsmundillCK;. Sporangia variously collected, cellular-
reticulated, destitute of any ring (as in Osmunda or Flowering
Fern), or with an imperfect trans- 1236

verse ring around the top (as in
Schizrca, Fig. 1293), opening
lengthwise by a regular slit.

9G6. Subord. Ophioglosscac. Si>o-

rangia spiked, closely sessile, naked,
coriaceous and opaque, not reticu-
lated, destitute of a ring, opening
by a transverse slit into two valves,
discharging the very copious spores
Avhich appear like floury dust.
Fronds straight, never rolled up (or
circinate) in the bud !

9G7. Ord. Lycopodiacctc ( Club-Moss

Family). Plants with creeping or

erect leafy stems, mostly branching ;

the crowded leaves lanceolate or

subulate, one-nerved. Sporangia

single and sessile in the axils of

the leaves, sometimes all crowded I2S5

at the summit under leaves which are changed into bracts and form

FIO. 1295. Lycopodium Carolinlanum, of the natural size. 1293. A leaf from the spike of
fructification, with the spore-case in its axil, and spores falling out. 1297. A group of four
larger spores (obphoridia) of Selaginella. magniSed. 129S. The same, separated 1299 A burst
spore-case of Selagiuella apus, with its four large spores.

502 ILLUSTRATIONS OK THE NATURAL ORDERS.

a kind of ament, one-celled, or rarely two- to three-celled, dehiscent,
containing either minute grains, appearing like line powder, or a few
rather large sporules ; both kinds often found in the same plant. —
Ex. Lycopodium (Club-Moss, Ground Pine), Selaginella. — Append-
ed to this family, rather than to the next (with which it has gener-
ally been associated), is the

9G8. Sllboi'll. IsoelincJC (Quillwort Family), consisting of a few
acaulescent submersed aquatics, with their sporangia in the axils
and immersed in the inflated base of the grassy subulate leaves. —
Ec. Isoetes.

9 GO. Ol'd. Ilydl'Oplcrilles. Aquatic or marshy cryptogamous plants,
of diverse habit, with the fructification borne at the bases of the
leaves, or on submerged branches : this consists of two sorts of or-
gans, contained in indehiscent or irregularly bursting involucres
(sporocarps). It comprises the

970. Subortl. Marsilaceffi (Pepperwort Family) ; with creeping stems ;
the leaves long-stalked, circinate in vernation, and of four obcordate
leaflets in Marsilea, or filiform and destitute of leaflets in Pilularia
(the Pillwort).

971. Sllbord. Salviniea;; which are free floating plants, with alter-
nate and sometimes imbricated sessile leaves ; the fructification
borne on the stem or branches underneath. — Ex. Salvinia, Azolla.
(For illustrations, see Manual of Botany, Plate 14.)

Class IV. Anopiiytes.

Vegetables composed of parenchyma alone, with acrogenous
growth, usually with distinct foliage, sometimes the stem and foliage
confluent into a frond.

972. Ol'd. Mlisci {Mosses). Low, tufted plants, always with a stem
and distinct (sessile) leaves, producing spore-cases which mostly
open by a terminal lid, and contain innumerable simple spores. The
fertilizing organs, or anther idia, have been elsewhere mentioned. In
Mosses these accompany the pistillidia ; the latter develop into the
capsule, or more properly the sporangium or spore-case. This is
rarely (in Andnea) dehiscent into four valves, or irregularly rup-
tured (in Phascum, &c). It usually opens by a lid (ppercidum) :
beneath the lid and arising from the mouth of the capsule are com-
monly either one or two rows of rigid processes (collectively the

CRYPT0GAM0U3 Oi: FLOWICULKSS PLANTS.

503

peristome), which are always some multiple of four: lho:e of (he
outer row are called teeth, of the inner, cilia. The spores which fill
the cavity commonly appear like an impalpable greenish powder.
The pedicel continued through the capsule forms the columella : en-
larged under the capsule it sometimes forms an apophysis. The

1305 1313 1311

OO 1306 1310 13CS

cabjptra separating early at its base is carried up on the apex of the
capsule ; if it splits on one side, it is hood-shaped or cnculliform, if
not, it is mitre-shaped or mitriform. The particular structure of all
our genera of Mosses, and of the following order, is illustrated in
the plates of the Manual of (lie Botany of the Northern United
States ; to which the student is referred for details.

073. Ol'il. IlepaliCEB {Liverworts). Frondose or Moss-like plants,
of a loose cellular texture, usually procumbent and emitting rootlets
from beneath ; the calyptra not separating from the base, but usually
rupturing at the apex ; the sporangium or capsule not opening by a

FIG. 1300. Mnium euspidatum. 1301. The calyptra detached from the spore-case 1302.
Magnified spore-case, from which the lid or operculum, 1303, has been removed, showing llio
peristome. 1334 A portion of the annulus or ling under the lid, more magnified. 1305. A
portion of the outer and inner peristome, highly magnified. 1306. The so-called flowers in a
your.g state, consisting of the pistillidia 9 , and tho antheridia <^, with some cellular jointed
threads intermixed ; the involucral leaves cut away. 1307. One of the antheridia more magni-
fied (with fome cccompanyir.g cellular threads), opening at the apex, and discharging the con-
tents 1S03 Simple peristome of Splachnum ; tho teeth united in pairs. 1309 Poublc pel in-
terne of Ily pnum ; the exterior spreading 1310 Physeomitrium (G\ mnOStomum) p> rifonnc.
13J1 Its calyptra, detached from, 1312, tho theca. 1313 The lid removed from the orifice,
which U destitute of a peristome.

504

ILLUSTRATIONS OF THE NATURAL ORDERS.

lid, containing spores usually mixed with elaters (which are thin,
thread-like cells, containing one or two spiral fibres, uncoiling elas-
tically at maturity). Vegetation sometimes frondose, i. e. the stem
and leaves confluent into an expanded leaf-like mass ; sometimes
foliaceous, when the leaves are distinct from the stem, as in true
Mosses : the leaves are entire or cleft, two-ranked, and often with an
imperfect or rudimentary row (amphigastria) on the under side of the
stem. The matured pistillidium forms the sporangium or capsule,
which is either sessile or borne on a long cellular pedicel, and de-
hiscent by irregular openings, by teeth at its apex, or lengthwise by
two or four valves. The perianth is a tubular organ enclosing
the cah/ptra, which directly includes the pistillidium. Surrounding
the perianth are involucral leaves of particular forms. The an-
theridia in the foliaceous species are situated in the 'axils of peri-
gonial leaves.

974. Subord. HicciaCCfl" consists of'a few chiefly floating plants, root-
ing from beneath, with their fructification immersed in the frond, the
sporangium bursting irregularly. No involucre nor elaters. — Ex.
Riccia.

975. Subord. AnillOCCrctCeC. Terrestrial frondose annuals, with the
fruit protruded from the upper surface of the frond. Perianth none.
Sporangium pod-like, one- or two-valved, with a free central colu-
mella. Elaters none or imperfect.

976. Subord. DlnrchailtiacCfP {True Liverworts). Frondose and ter-
restrial perennials, growing in wet places, with the fertile receptacle
raised on a peduncle, capitate or radiate, bearing pendent calyptrate

FIO. 1314, 1315. Riccia natans, about the natural size 1316 Magnified section through
the thickness of the frond, showing the immersed sporangia ; one of which has burst through
and left an effete cavity. 1317. Magnified vertical section of one of the sporangia, with the
contained spores. 1318. Sporangium torn away from the base, and a quaternary group of
spores, united and separated.

CUYI'TOGAMOUS OR FLOWEKLESS PLANTS.

505

sporangia from the under side : these open variously, but are not
four-valved. Elaters with two spiral fibres.

977. Subonl. JungCrmanniaCCiC. Frondose or mostly foliaceous
plants ; with the sporangium dehiscent into four valves, and the
spores mixed with elaters.

Class V. Tiiallopiiytes.

Vegetables composed of parenchyma alone, forming a mass or
stratum (thallus, 109, 727), or consisting of a congeries of cells, or
even of separate cells, never exhibiting a marked distinction into
root, stem, and foliage, or into axis and leaves.

978. Ord. Lic'icnes {Lichens) form the highest grade of this lower
series. They consist of flat expansions, which are rather crustaceous
than foliaceous ; while some are nearly pulverulent. In several the
vegetation rises into a kind of axis, or imitates stems and branches ; as
in the Cladonia coccinea, which abounds on old logs (Fig. 1327) ; or
in Cladonia rangiferina, the Reindeer Moss ; also in Usnea, where
it forms long, gray tufts, hanging from the boughs of old trees in our
Northern forests. Lichens are never aquatic, but grow on the ground,
on the bark of tree;, or on exposed rocks, to which the proper rock-
Lichens adhere by their lower surface, with great tenacity, while by

Fid. 1319 Steetzia Lyellii, with the young fructification still included in the tubular peri-
anth 1320. Dehiscent sporangium of a Jur.germannia, on its fruit-stalk, with some of the
leaves at its base, magnified enough to exhibit its cellular structure 1321. Two elaters from
the same (a, in an entire state ; b, with only the threads remaining), and some spores, highly
magnified

43

.50 G

ILLUSTRATIONS OF THE NATURAL ORDERS.

the upper they draw their nourishment directly from the air. The
fructification is in cups, or shields {apothecia), resting on the surface
of the thallus, or more or less immersed in its substance, or else in
pulverulent spots scattered over the surface. A magnified section
through an apothecium (Fig. 1324) brings to view a stratum of
elongated sacs (asci), with filaments intermixed, as seen detached
and highly magnified at Fig. 1325. Each ascus, or sac, contains a
few spores : these divide into two, which, however, generally remain

coherent. For a description of the Lichens of this country, the
student is referred to Professor Tuckerman's Synopsis of the Lu
chenes of New England, the other Northern States, S>-c. and to his
Lichenes Amer. Sept. Exsiccati, illustrating them by named speci-
mens.

FIG 1322 A stone upon which several Lichens are growing, such as (passing from left to
right) ParmeHa conspersa, Sticta miniata, Lecidea geographica (so called fro.n its patches re-
sembling the outline of islands, &c. on maps), &c , &c 1323 Piece of the thallus of Parme-
lia conspersa, with a section thiough an apothecium. 1324. Section of a smaller apothecium,
more magnified 1325. Two asri and their contained spores, with the accompany ing filaments,
highly magnified 1320. Section of a piece of the thallus of Sticta miniata, showing the im.
mersed apothecia. 1327. CladonU coecinea, bearing itJ fructification iu rounded red masses
ou the edges of a rai.-ed cup.

CRYPTOGAMOUS OR FLOWKRI.KSS PLANTS. 507

979. 0/(1. Fungi {Mushrooms, Moulds, $c.) are parasitic (150, 153)
flowerless plants, either in a strict sense, as living upon and draw-
ing their nourishment from living, though more commonly languish-
ing, plants and animals, or else as appropriating the organized mat-
ter of dead and decaying animal and vegetable bodies. Hence they
fulfil an office in the economy of creation analogous to that of the
infusory animalcules. Those Fungi which produce Rust, Smut,
Mildew, &c. are of the first kind ; those which produce Dry-rot, &c.
hold a somewhat intermediate place ; and Mushrooms, Puff-balls,
&c. are examples of the second. Fungi are consequently not only
destitute of anything like foliage, but also of the green matter, or
chlorophyll, which appears to play an essential part in vegetable
assimilation. A full account of the diversified modifications of struc-
ture that Fungi display, and of the remarkable points in their
economy, would require a large volume. We will notice three sorts
only, which may represent, the highest, and nearly the lowest, forms
of this vast order or class of plants. They all begin (in germina-
tion or by offsets) with the production of copious filamentous threads,
or series of attenuated cells, appearing like the roots of the fungus
that arises from them (Fig. 1328, 1330), and to a certain extent
performing the functions of roots : this is called the mycelium, and
is the true vegetation of Fungi. The subsequent developments
properly belong to the fructification, or are analogous to tubers,
rhizomas, &c. In one part of the order, the masses that arise, of
various definite shapes, and often attaining a large size, contain in
their interior a multitude of asci (Fig. 1329), enclosing simple or
double sporules, just as in Lichens. The esculent Morel has this
kind of fructification ; as well as the less conspicuous Sphffiria (Fig.
1328), which is in other respects of a lower grade. The Agarics,
like the Edible Mushroom (Fig. 1330), produce their spores in a
different way. Rounded tubercles appear on the mycelium ; some
of ther-e rapidly enlarge, burst an outer covering which is left at the
base (the volva, or wrapper), and protrude a thick stalk (stipes),
bearing at its summit a rounded body that soon expands into the
pileus, or cap. The lamellae, or gills (hymenium), that occupy its
lower surface, consist of parallel plates (Fig. 1331), which bear
naked sporules over their whole surface. A careful inspection with
the microscope shows that these sporules are grouped in fours ; and
a view of a section of one of the gills shows their true origin (Fig.
1332). Certain of the cells (basidia), one of which is shown more

508

ILLUSTRATIONS OF THE NATURAL ORDERS.

magnified at Fig. 1333, produce four small cells at then- free sum-
mit, apparently by gemmation and constriction : these are the spores.
It is maintained that the larger intermingled cells, (of which .one is
shown at Fig. 1332, «,) filled with an attenuated form of matter, are
the analogues of antheridia. The lowest Fungi produce from their
mycelium only simple or branching series of cells (Fig. 92-94).
The mycelium itself either ramifies through decaying organized
matter, as the Moulds, &c. ; or else — like the Blight and Rust in
grain, and the Mascardine so destructive to silkworms, and others

so destructive to the Grape, the Potato, &c. — it attacks and spreads
throughout living tissues, often producing great havoc before its
fructification is revealed at the surface. Sometimes the last cells of
the stalks swell into a vesicle, in which the minute sporules are
formed ; as in Fig. 92. Sometimes the branching stalks bear single
sporules, like a bunch of grapes (Fig. 94), or long series of cells, or

FIG. 1328. Spbasria rosella. 1329. Asci from its interior, containing sporules, highly mag-
nified. 1330 Agaricus campestris, the Kdible mushroom, in its various stages. 1331. Section
through the pileus, to display the gills. 1332. A small piece of a slice through the thick-
ness of one of the gills, magnified ; showing the spores borne on the summit of sail nt cells
of both surfaces. 1333 Oue of the sporule-bearing cells, with tome subjacent tissue, mora
magnified

CRVPTOGAMOUS OR FLOVVERLESS TLAXTS. 509

sporules, in rows, like the beads of a necklace (Fig. 9.3), which,
separating, become the rudiments of new plants.

980. Ord. AlgrC (Seaweeds). This vast order consists of aquatic
plants, for the most part strictly fo, but some grow in humid ter-
restrial situations. The highest forms are the proper Seaweeds
( Wrack, Tang, Dulse, Tangle, &c.) ; "some of which have stems ex-
ceeding in length (although not in diameter) the trunks of the tallest
forest-trees, while others have leaves (fronds) which rival in expan-
sion those of the Palm." " Others again are so minute as to be
wholly invisible, except in masses, to the naked eye, and require the
highest powers of our microscopes to ascertain their form and struc-
ture." Some have the distinction of stems and fronds ; others show
simple or branching solid stems only ; and others flat foliaceous ex-
pansions alone (Fig. 95), either green, olive, or rose-red in hue.
From these Ave descend by successive gradations to simple or
branching series of cells placed end to end, such as the green Con-
fervas of our pools, and many marine forms : we meet with congeries
of such cells capable of spontaneous disarticulation, each joint of
which becomes a new plant, so that the organs of vegetation and of
fructification become at length perfectly identical, both reduced to
mere cells; and finally, as the last and lowest term of possible vege-
tation, we have the plant reduced to a single cell, giving rise to new
ones in its interior, each of which becomes an independent plant
(Fig. 79-83, 18-22). Our Alga? should be studied by the aid of
the admirable Nereis Boreali- Americana, or History of the Marine
Alga of North America, by Professor Harvey, published by the
Smithsonian Institution. For the fresh-water species we have no
American work. The main divisions of Alga3 are into the following
suborders.

981. Sllbord. Melanospcrmcac, or FucaCC8E, the Olive-green Seaweeds ;
having dark-colored spores and generally an olive-green color, such
as the common Rockweed, Gulfweed, &c. The fertilization of these
spores has already been described (661).

982. Subord. RhildospermCfe, or Florideae, the Rose-red Seaweeds, so
called from their prevailing color. These, the most beautiful of
Algaj (including the Dulse, Laver, &c.) have two kinds of spores;
one large, simple, and superficial ; the others dispersed through the
interior of the frond, and formed four together in a mother cell.

983. SubOrd. CIlloi'OSpcrmCiT, the Bright-green Algce, the spores and
the vegetation of which are generally of a lively green hue, are more

43*

510

ILLUSTRATIONS OF THE NATURAL ORDERS.

pimple m structure, arid include the fresh-water kinds generally, as
■well as numerous marine species ; among them those of single rows of
cells, or of single cells (100- 105, G56- G60). Some of these fruc-
tify by conjugation (G55-657), as is the case in those simplified
forms which compose the

984. Suboi'd. Dcsmidiacesc, which are microscopic and infasory green
Algne of single cells (Fig. 100, 655), often of crystal-like forms, in-
vested with mucus, and belonging to fresh water. They multiply
largely by division, but strictly propagate only by conjugation. Many
of them have long been claimed for the animal kingdom, or es-
teemed of ambiguous nature, on account of the free movements
they exhibit ; but this affords no real distinc-
tion. (Chap. XII., XIII.) More ambiguous
still, and on the lowest confines of the vegeta-
ble kingdom, are those minute vegetables, as
they doubtless are, Avhich constitute the

985. Subord. Diatomaccrc. These differ
from the last chiefly in the brown instead of
green color of their contents, in the siliceous
and durable nature of their cell-wall, and in
being natives of salt instead of fresh water.
Their movements, as they break up from
their connections, are still more vivid and
varied. Some are fixed ; others are free.
Some are extremely minute : others form
clusters of cells of considerable size. All
require a compound microscope for their
study, and a full treatise is needed to do them
justice.

986. Ord. CharaceSB. The Chara Family
consists of a few aquatic plants, which have

1335 1331 all the simplicity of the lower Alga? in their

vegetation, being composed of simple tubular cells placed end to
end, and often with a set of smaller tubes applied to the surface of
the main one (Fig. 1335, 1336). Hence they have been placed
among Alga;. But their fructification is of a higher order. It con-
sists of two kinds of bodies (both shown in Fig. 1335), of which

FIG. 1334 Branch of the common Chara, uearly the natural size. 1335 A portion magni-
fied, showing the lateral tubes enclosing a large ceutral one (a portion more magnified at 1336) ;
also a spore, iuvested by a set of tubes twisted spirally arouDd it ; and the antheridium borne
at its base.

TIIK ARTIFICIAL SYSTKM 01' LIXNvKl'S. Oil

the smaller (and lower) contains antheridia of curious structure,
provided with slender and active spermatozoids, while the upper
and larger is a sporocarp, formed of a budding cluster of leaves
wrapped around a nucleus, which is a spore or sporangium. The
order might perhaps have been introduced between the Equisc-
taceaa (to which the verticillate branches show some analogy) and the
Ilydropterides ; but its true position is hard to determine.

C II AFTER I V .

OF THE ARTIFICIAL SYSTEM OF LIXNMEUS.

987. The difference in principle between an artificial and a natu-
ral system of classification has already been indicated (715). No
one better understood this than Linnaeus, "when, finding it impossible
in his day to make a natural classification available for ordinary use,
he proposed, as a temporary substitute, the elegant artificial scheme
which bears his name. As this system is identified with the history
of the science, which in its time it so greatly promoted, and as most
systematic works have until recently been arranged upon its plan, it
is still necessary for the student to understand it. Its principles are
so simple, that a brief space will amply suffice for its explanation.

988. It must be kept in mind, that an artificial scheme does not
attempt to fulfil all the conditions of natural-history classification.
Its principal object is to furnish an easy mode of ascertaining the
names of plants ; their relationships being only so far expressed as
the plan of the scheme admits. All higher considerations are of
course sacrificed to facility. In the Linneean classification, the
species of a genus are always kept together, whether or not they all
accord with the class or order under which they are placed. Its
lower divisions, therefore, namely, the genera and species, are the
same as in a natural system. But the genera are arranged in arti-
ficial classes and orders, founded on some single technical character,
and have no necessary agreement in any other respect ; just us
words are alphabetically arranged in a dictionary, for the sake of
convenience, although those which stand next each other have, it
may- be, nothing in common beyond the initial letter.

612 THE ARTIFICIAL SYSTEM OF LINKJEUS.

• 989. The classes and orders Linnanis founded entirely upon the
number, situation, and connection of the stamens and pistils ; the
office and importance of which he had just set in a clear light.

990. The classes, twenty-four in number, were founded upon
modifications of the stamens, and have names of Greek derivation
expressive of their character. The first eleven comprise all plants
with perfect flowers, and with a definite number of equal and un-
connected stamens. They are distinguished by the absolute number
of these organs, and are designated by names compounded of Greek
numerals and the word andria (from dvrjp), which is used meta-
phorically for stamen, as follows : —

Class 1. Mon andria includes all such plants with one stamen to
the flower ; as in Ilippuris.

2. Diandria, those with two stamens, as in the Lilac.

3. Triandria, with three stamens, as in the Valerian, &c.

4. Tetr andria, with four stamens, as in the Scabious.

5. Pentandria, with five stamens, the most frequent case.

6. Hexandria, with six stamens, as in the Lily Family, &c.

7. Heptandria, with seven stamens, as in Horsechestnut.

8. Octandria, with eight stamens, as in Evening Primrose, &c.

9. Enneandria, with nine stamens, as in the Rhubarb.

10. Diccandria, with ten stamens, as in Rhododendron.

11. Dodecandria, Avith twelve stamens, as in Asarum and

the Mignonette ; extended also to include those with
from thirteen to nineteen stamens.

991. The two succeeding classes include plants with perfect flow-
ers, having twenty or more unconnected stamens, which, in

12. Icosandria, are inserted on the calyx (perigynous, 467),

as in the Rose Family ; and in

13. Polyandria, on the receptacle (hypogynous, 4G6), as in

the Buttercup, Anemone, &c.

992. Their essential characters are not indicated by their names ;
the former merely denoting that the stamens are twenty in number ;
the latter, that they are numerous. — The two following depend upon
the relative length of the stamens, namely,

14. Did yx ami A, including those with two long and two short

stamens (Fig. 407) ; and

15. Tetradynamia, those Avi h four long and tAAro short sta-

mens, as in Cruciferous flowers (Fig. 406).

THE ARTIFICIAL SYSTEM OF LINNJEUS. 513

993. Their names are Greek derivatives, signifying in the former
that two stamens, and in the latter that four stamens, are most pow-
erful. — The four succeeding are founded on the connection of the
stamens: —

16. MonadelphiA (meaning a single fraternity), with the

filaments united in a single set, tube, or column, as in
all the Mallow Family, &c.

17. Diadeephia (two fraternities), with the filaments united

in two sets or parcels.

18. Poeyadeepiiia (many fraternities), with the filaments

united in more than two sets or parcels.

19. Syngenesia (from Greek words signifying to grow to-

gether), with the anthers united in a ring or tube, as in
all Compositae (844).

994. The next class, as its name denotes, is founded on the union
of the stamens to the style : —

20. Gynandiua, with the stamens and styles consolidated, as

in the Orchis Family (Fig. 468).

995. In the three following classes, the stamens and pistils are
found in separate blossoms : —

21. Moncecia (one household) includes all plants where the

stamens and pistils are in separate flowers on the same
individual ; as in the Oak, &c.

22. Dicecta (two households), where they occupy separate

flowers on different individuals ; as in the Willow, Pop-
lar, Moonseed (Fig. 413, 414), &c.

23. Poeygamia, where the stamens and pistils are separate

in some flowers and united in others, either on the
same, or two or three different plants ; as in most
Maples.

996. The only remaining class,

24. Cuyptogamia, is inferred to have concealed stamens and

pistils (as the name imports), or the analogues of theso
organs, and includes the Ferns, Mosses, Lichens, &c.t
which are now commonly termed Cryptogamous or Flow-
erless Plants (651).

997. The characters of the classes may be presented at a single
view, as in the subjoined analysis : —

514

THE ARTIFICIAL SYSTEM OF LINNAEUS.

<< g 5 g 3 i

II

t-i c4 CO ^. **3 O L-

so ci o pj ci yi

O g

•# o

is

n

a

y. c S r>

S i S >
S — PhM

. 'i '

s °

sla

c a a .

333.

|| § jj
ec« S

j= J5 x ja

>>>>>>>>

— — ^ -o

5
8

B3 1

SO ft.
S3 g

* *

• 2'^

• c o

J3 *»

. .£ §

£'■3

. *o* .

' . ' .si

oS

w

£ »- .

w

' ' .11

111 f '

5

r-l 5*1 CO *}* Ii3 CO l-

C

gs 3 S 3 3 3

S

• • i £

o o

1 o S

ooaoi-i Oi-i

HH«M

s

71

III

I fi-
ll

ia

THE AKTIIICIAL SYSTEM OF LINNiEUS. 515

998. The orders, in the first thirteen classes of the Linntcnn ar-
tificial system, depend on the number of styles, or of the stigmas
when the styles are wanting ; and are named by Greek numerals
prefixed to the word gynia, used metaphorically for pistil, as

follows : —

Order 1. Monogynia embraces all plants of any of the first thir-
teen classes, with one style to each flower.

2. Digynia embraces those with two styles.

3. Trigynia, those with three styles.

4. Tetra gynia, those with four styles.

5. Pentagynia, those with five styles.
G. Hkxagynia, those with six styles.

7. Heptagynia, those with seven styles.

8. Octogynia, tho^e with eight styles.

9. Ennkagynia, those with nine styles.

10. Decagynia, those with ten styles.

11. Dodecagynia, thoie with eleven or twelve styles.

12. Polygynia, those with more than twelve styles.

999. The orders of class 14, Didynamia, are only two ; namely,

1. Gymnospkrmia, meaning seeds naked, the achenia-like

fruits having been taken for naked seeds.

2. Angiospermia, with the seeds evidently in a seed-vessel

or pericarp.

1000. The 15th class, Tetradynamia, is also divided into two or-
ders, which are distinguished merely by the form of the pod : —

1. Siliculosa; the fruit a silicic (621), or short pod.

2. Siliquosa ; fruit a silique (G20), or more or less elon-

gated pod.

1001. The orders of the 16th, 17th, 18th, 20th, 21st, and 22d
classes depend merely on the number of stamens ; that is, on the
characters of the first thirteen classes, whose names they likewise
bear : thus,

Order 1. Moxandiua, with one stamen ; 2. Diaxdria, with two
stamens ; and so on.

1002. The orders of the 19th class, Syngenesia, are six ; namely,
1. Polygamia jequalis, where the flowers arc in heads

(compound flower, 394), and all perfect.

516 THE ARTIFICIAL SYSTEM OF LINNAEUS.

2. Polygamia BUPERFLUA, the same as the last, except that

the rays, or marginal flowers of the head, are pistillate
only.

3. Polygamia frustranea, those with the marginal flowers

neutral (Fig. 324, 325), the others perfect.

4. Polygamia necessaria, where the marginal flowers are

pistillate and fertile, and the central, staminate and
sterile.

5. Polygamia segregata, where each flower of the head

has its own proper involucre.

6. Monogamia, where solitary flowers (that is, not united

into a head) have united anthers, as in Lohelia.

1003. The 23d class, Polygamia, has three orders, founded on the
characters of the two preceding classes ; namely,

1. Mon(ecia, where hoth separated and perfect flowers are

founded in the same individual.

2. Dicecia, where they occupy different individuals.

3. Trkecia, where one individual bears the perfect, another

the staminate, and a third the pistillate flowers.

1004. The orders of the 24th class, Cryptogamia, are natural or-
ders, and therefore not definable by a single character. They are,

1. Filices, the Ferns.

2. Muse i, the Mosses.

3. Alg^e, which, as left by Linnaeus, comprised the Hepatica;,

Lichens, &c., a3 well as the Seaweeds.

4. Fungi, Mushrooms, &c

APPENDIX.

Or the Signs and Abreviations employed in Botanical Writings.

Linn>kus adopted the following signs for designating the duration of a
plant, viz. : —

(v) An annual plant.
g A biennial plant.
21 A perennial herb.
\ A shrub or tree.

Among the signs recently introduced, the following have come into
general use : —

O A monocarpic (once-flowering) plant, whether annual or biennial.

© An annual plant.

(§) A biennial plant.

21 A perennial herb.

\ A plant with a woody stem.

g A staminate flower, or plant

$ A pistillate flower, or plant.

£ A perfect flower, or a plant bearing perfect flowers.

1 The exclamation point is employed as the counterpart of the note of
interrogation. When it follows the name of an author appended to
the name of a plant, it imports that an authentic specimen of the
plant in question, under this name, has been examined by the writer:
when it is appended to a locality, it signifies that the writer has seen or
collected specimens of the plant from that locality, &c.

? The note of interrogation is employed to denote doubt or uncertain-
ty ; and is affixed either to a generic or specific name, or to that of an
author or locality cited.

* As used by De Candolle, indicates that a good description is found at
the reference to which it is appended. It is not in common use.
44

518 APrrxDix.

Those abbreviations of the names of organs which are commonly em-
ployed, such as Cal. for calyx, Cor. for corolla, Fl. for flower, Fr. for
fruit, Gen. for genus, Hah. for habitat, Herb, for herbarium, Hort. for
garden, Mus. for Museum, Ord. for order, Had. (Radix) for root, Syn. for
synonymy, Sp. or Spec, for species, T ar. for variety, &c, scarcely require
explanation.

V. sp. denotes, in general terms, that the writer has seen the plant under

consideration.
V. s. c. (Vidi siccam cuitam), that a dried specimen of a cultivated plant

has been examined.
V. s. s. (Vidi siccam spontaneam), that a dried specimen of the wild

plant has been examined.
V. v. c. (Vidi vicam cuitam), that the living cultivated plant has been

under examination.
V; v. s. (Vidi vivam spontaneam), that the wild plant has been examined

in a living state.
The names of authors, when of more than one syllable, are commonly
abridged by writing the first syllable, and the first letter or the first con-
sonant of the second. Thus, Linn., or L., is the customary abbreviation
for Linnaeus; Juss. for Jussieu ; Will d. for Willdenow; Muhl. for Muh-
lenberg; Michx. for Michaux; Rich, for Richard; De Cand., or DC,
for Dc Candollc ; Hook, for Hooker ; Endl. for Endlicher ; Lindl. for
Lindlev-, &c.

Of Collecting and Preserving Plants.

1. The botanist's collection of specimens of plants, preserved by drying
under pressure between folds of paper, is termed a Horlus Siccus, or com-
monly an Herbarium.

2. A complete specimen consists of one or more shoots, bearing the
leaves, flowers, and fruit ; and, in case of herbaceous plants, a portion of
the root is also desirable.

3. Fruits and seeds which are too large to accompany the dried speci-
mens, or which would be injured by compression with sections of wood,
&c, should be separately preserved in cabinets.

4. Specimens for the herbarium should be gathered, if possible, in a dry
day ; and carried either in a close tin box, as is the common practice, or
in a strong portfolio, containing a quire or more of firm paper, with a few
loose sheets of blotting-paper to receive delicate plants. They are to
be dried under strong pressure, (but without crushing the parts,) between
dryers composed of six to ten thicknesses of bibulous paper: which should
be changed daily, or even more frequently, until all the moisture is ex-
tracted from the plants; — a period which varies in different species, and

APPENDIX. 519

■with the season, from two or three days to a week. All delicate speci-
mens should be laid in folded sheets of thin and smooth bibulous paper
(such as tea-paper), and such sheets, filled with the freshly gathered
specimens, are to be placed between the dryers, and so transferred entire,
day after day, into new dryers, without being disturbed, until perfectly
dry This preserves all delicate flowers better than the ordinary mode of
shifting of the papers which are in immediate contact with the specimens,
and also saves much time usually lost in transferring numerous small
specimens, one by one, into dry paper, often to the great injury of the deli-
cate corolla, &c.

5. The dried specimens, properly ticketed with the name, locality, &c,
and arranged under their respective genera and orders, are preserved in
the herbarium, either in separate double sheets, or with each species at-
tached by glue or otherwise to a half-sheet of strong white paper, with the
name written on one corner. These are collected in folios, or elscdie flat
(as is the best mode) in parcels of convenient size, received into compart-
ments of a cabinet, with close doors, and kept in a perfectly dry place.

G. The seeds of plants intended for cultivation, which are to be trans-
ported to a distance before being committed to the earth, should first be
dried in the sun, wrapped in coarse paper, and preserved in a dry state.
They should not be packed in close boxes, at least so long as there is dan-
ger of the retention of moisture.

7. Roots, shrubs, &c, designed for cultivation, should be taken from tho
ground at the close of their annual vegetation, or early in the spring before
growth recommences, and packed in successive layers of slightly damp (but
not wet) Peat-moss (Sphagnum). Succulent plants, however, such as
Cacti, may be packed in dry sand.

8. Plants in a growing state can only be safely transported to a consider-
able distance, especially by sea, in the closely glazed cases invented by Mr.
Ward ; * where they are provided with the requisite moisture, while they
are sufficiently exposed to the light.

* On the Growth of Plants in Closely Glazed Cases, by N B. Ward, F. L S.,
London, 1842. — Ed. 2, 1853.

GLOSSARY

OF ENGLISH BOTANICAL TERMS, EMPLOYED IN BOTANICAL
DESCRIPTIONS, COMBINED WITH AN

INDEX.

[The numerals without any prefix refer to the pages of the work : those preceded by fig. to
figures.]

A, privative, as the initial in many |
words of Greek derivation, signifies '
the absence of the organ men-
tioned ; as, apetalous, destitute of
petals ; aphyllous, leafless. In
words beginning with a vowel this
prefix is changed to an ; as, amin-
thous, flowerless; unantherous, des-
titute of anthers.

Abbreviations. The customary ones
are mentioned on p 518.

Aberrant (wandering) : applied to spe-
cies, genera, &c. which differ in
some respect from the usual or nor-
mal character of the group they
belong to.

Ahicti'neoc, 480.

Abnormal : differing from the normal or
usual stiucture.

Aboriginal: strictly native ; indigenous.

Aboition: the non-formation or imper-
fect formation of an organ, 255.

Abortive organs, 258.

Abrupt: terminating suddenly.

Abruptly pinnate, 1 63, fig 290.

Absorption, 80.

AcanthaccsE, 447.

Acantlwc/adots: with spiny branches.

Acantliophoious: spine-bearing.

Acaulescent : stcmless, or apparently so,
i e. without a proper caul is; 91.

Accessor//: something additional.

Accessory buds, 98.

Accessory fruits, 318.

Accrescent : increasing in size after flow-
ering, as the calyx of Physalis.

44*

Accrete: grown together.

Accumbent: lying against, especially

edgewise against another body;

.326, 390, fig. 700.
Acephalous : headless
Accraceas, or Accrinca?, 410
.4eero.se: needle-shaped, like the leaves

of Pines, &c. ; 166, fig. 212, 213.
Aceld bidiform or acetabulous ; saucer-
shaped.
Achenium (pi. achenia). a one-seeded

seed-like fruit ; 313, fi? 566-573.
Achlanajdeous : destitute of calyx and
„ corolla, 261.
Acids, 56, 195.
Acicu/ar : slender needle-shaped or

bristle-shaped.
Acies : the edge of a thing.
Acindciform : scymitar-shaped, like

some bean-pods.
Acines (acini) : the separate grains or

carpels of an aggregate fleshy fruit,

like the raspberry, as the term is

now generally used ; classically, the

dcinus meant the whole bunch of

such fruits
Acoti/le'donous : destitute of cotyledons.
Acrobri/ous: budding from the apex

only ; same as
Aodr/enous: growing from the apex,

'370.
Acrogens, Acrogenous plants, 370. 499.
Acramp/iibri/ous : growing from botli

ends and over the surface.
Aculeate : prickly ; beset with prickles

(aculei) ; 52.

522

GLOSSARY AND INDEX.

Acdhohite : diminutive of the last : i. c.
beset Avith small or few prickles.

Acuminate: ending in a narrowed or
prolonged and tapering point; 1G2,
fig. 2G8, 239.

Acutangular : sliarp-anglcd ; as the
stems of Scirpus pungens.

Acute: merely sharp-pointed; ending
liy an acute angle ; 162, fig:. 269.

Adelplmtis (stamens) : joined by their
filaments or clustered into a brother-
hood (adilpliia).

Adherent: sticking to, or, commonly,
growing fast to, another body, 252.

Adnate: giown fast to, or formed in
union with, another body, as the
calyx-tube of the Gooseberry and
Cranberry (fig. 391) to the ovary,
251, 252. Attached by its whole
length, as the anther of Liriodcn-
dion, 282, fig. 470, and of Asaruni,
fig. 472.

Adnation : the union of heterogeneous
parts, 250.

Adpressed, or appi eased: brought into
contact or nearly, but not united

Adscendent, or ascending : rising gradu-
ally upwards, 102.

Adsurrjmt, orassmijeiit: rising upwards

Adventitious, advent ve : found out of
the natural place.

Adventitious buck. 82, 98.

sEquilateial : equal-sided ; opposed to
oblique.

Aerial: growing in the air.

Aeital loots, 85

Aerophi/te : same as Air-plant.

sEstival: relating to summer.

yEstivation ; arrangement of floral or-
gans in the bud, 2G9.

Affinity: true and near relationship ;
i c species have affinity when they
resemble each other in their prin-
cipal points of structure, or, in other
words, arc constructed throughout
upon the same particular plan or
. type. (Sec Analo./i/.)

Agamous or Aijdmic : destitute of sexes

Agglomerate or aggregate : heaped or
crowded into a cluster.

Aggregate fruits, 317.

Air-cells, a'r-passages, 50.

Air-plants, 87.

Akeniuin or akene : Pec achenium.

Ala (pi. aire) ; a wing ; the side petals
of a papilionaceous flower; 253,
fig. 392, b.

Ahhdstrum: a flower-bud.

Alar ; borne in the forks of a stem.

Alate : winged ; i c. furnished with any
broad and thin adherent appendage,
as the seeds of Trumpet Creeper,

fig. G01, Ihc leafstalks of the Or-
ange, Rhus Copallina, &c , and
the stem of the common Thistle.

Albescent: whitened, or hoary-white.

Albumen, a vegetable product, 198.

Albumen of the seed, 7G, 322

Albuminous (seeds) : furnished with
albumen, 323.

Alburnum: sapwood, 126.

Alga;, 509.

Alijologi/ : the science relating to Algae.

Alismacca:, 487.

Alkaloids, 57.

Alliaceous: like the garlic or onion.

Alliances : natural groups of nearly re-
lated orders, 374.

Allspice. 418.

Almond, 415, 417.

Alpine: growing on the higher parts
of the Alps, and in general on
mountains above the limits of trees.

Aloes, 493.

Alsi'ncai, 395.

Alternate, (leaves) : situated one after
another, 78, 97, 133. Petals, sta-
mens, &c arc said to alternate w ith
adjacent organs, when they stand
over the intervals between them,
235

Alternation of parts, 235.

Alveolate: honeycombed; having deep
angular cavities separated by thin
partitions, as the receptacle of Cot-
ton-Thistle, fig. 898.

Amarantaceas. 4G5.

Amaryllidaceoc, 491.

Anient: a catkin ; a peculiar scaly spike ;
213. fig 312.

Amentaceous : rescmblingor bearing cat-
kins.

Amnios: the embryo-sac. 304.

Amorphous : shapeless, i. c. of no defi-
nite or regular form.

Ampliibrjons : growing by additions
over the whole periphery.

Amphicdrpous, or amphic&rpic: produc-
ing two kinds of fiuit; as in the
genus Amphicarpoea, so named on
this account.

Am phiga stria : the peculiar stipule-like
leaves of certain Hcpatieaj, 504

Ampltitiopons,ov amphitropal, ovule or
seed, 30 J, fig 528.

Amp/ectant : embracing.

Ample'xuaul (leaves, &c.) : clasping the
stem by a broad base or insertion.

Ampulldceous: shaped like an ampulla
or flask-shaped vessel ; swelling out
at the base or middle.

Amvgdalcoa, 415.

Amylaceous: composed of starch (dmy-
lum), or resembling starch.

GL.OS3A.iiY AND IXDICX.

523

Amyloid, 55.

Amyridacem, 407.

Anacardiaeeaj, 406.

Analogy: resemblance in certain re-
spects. As distinguished from af-
Jinitg it means resemblance in cer-
tain respects only, not in the whole
plan of stiuci ure. Thus a Ranun-
culus is analogous to a Potcntilla,
hut there is no near affinity or re-
lationship between the two. And
the tendiil of a Pea, that of a Smi-
lax, and that of the Grape- Vine are
analogues, i e. are analogous oigans,
but are not homologies'; for the (iist
answers to a leaf, the second to
stipules, and the third to a stem
The spur of a Larkspur (fig 398)
is analogous to one of the live spurs
of Columbine (fig 6-16), but not
homologous with it, for the first is
a sepal, and the second a petal.

Andndious: destitute of stamens.

Andntkerous ; destitute of anthers.

Avanthous: without flowers.

Anastomosing : connected by cross
branches into a network, as the
veins of animals, and the so-called
veins of reticulated leaves, 49, 54.

AndtrofiO'JS, or andti opal, seeds or ovules,
299, fig. 529.

Anclpital: with two edges, as the stem
of Sisyrinchiuin anceps.

Andraci um : the stamens of a flower,
taken as a whole, 223.

And i dggnoiis : bcai ing both stamens and
pistils in separate flowers of the
, same inflorescence.

Andiophore: a column of united stamens,
or any support on which the sta-
mens are raised

Andions, in woids of Greek derivation,
refers to the stamens : see dmn-
, dious, &c.

AndiosjOies, 335

Anfrdrtuose or an ft acinous : abruptly bent
hither and thither, as the stamens
of Melon, fig. 467.

Angiospcrmia, 515.

Augiospe'rmous ( Angiosperma?, Angio-
sperms) : producing seeds in a peri-
carp, 371, 375.

Angostura bark, 406.

Angular divergence of leaves, 135.

Anise, 426.

Antsoineious (flower) : of unequal num-
ber in the different circles ; unsym-
metrical.

Anisop/njdous : unequal-leaved, as when
the two leaves of the same pair arc
of unequal size.

Anisos'.tmono :s : when the number of

the stamens is different from that
of the petals.
Annual: lasting not above one year or
one season, 83.

Annular : in the form of a ring.

Annular duels, 46

Annulate: marked with rings or circu-
. lar transverse lines.

Annulus: the ring of the spoic-casc of
true Perns, 501, fig. Ii89 : that of
the mouth of the spoie-case or cap-
sule of Mosses, 503, fig. 1G04.

Anonaccaj, 382.

Ano/i/ii/tes (top-growing plants, of the
same meaning as Acrogcns ?), 370,
502.

Anfeposition, 248.

Antei for: as to position in the flow-
er, on the side next the biact, 237.

Anther : the pollen-bearing part of a sta-
men, 223, 281.

Anthoidium (pluial, anther idia), 334,
5U2.

A nthei ifci ous : anther-bearing.

A'nthesis: the time whcii the flowcropens
and pei forms its functions, or the
act of expansion in a flower, 271.

Anthocui pons fruits, 318.

Anthoccrotea!, 504.

Antlwdntm : a technical name for the
capituluin or head of flowers of a
plant of the order Compositn:.

Antlio/i/sis : the retrograde mctamorpho-
, sis of a flower.

Anthophore: the stalk orintemodc which
is sometimes developed between the
calvx and the corolla, as in Silene,
, 267, fig 432.

Ant icons: anterior, or facing foi wards.

Antitiupous, or an til) opal: (reversed;)
applied to the embryo, it means one
with the radicle pointing away
fiom the hilum, as in fig 600 and
fig. 606.

AntrO'se: directed upwards or forwards.

Ape'lalous : destitute of petals or corolla,
260.

Aphyllous: destitute of leaves, at least
, in the form of foliage

Apical: relating to the apex.

Apiculate : terminating in an abrupt
shoit point or tip.

Apocarpous pistils : those not united into
one body or compound pistil, 290.

Apocynacea;, 4 57.

Apophysis ■■ any irregular enlargement,
like that of the spore-case of Splacli-
num and some other Mosses, 503

Apothecivm: the shield or shield-shaped
fructification of most Lichens, 506.

Append! c, appendage: any superadded
part.

524

GLOSSARY AND INDEX.

Appendiculate: having an appendage.
Apple, 410.

Appesstd: lying flat against, or close-
pressed together.
Apricot, 417.
Apterous : wingless ; having no dilated

border or appendages.
Aquatic : living in water, either sub-
mersed or raised partly out of it.
Aquifoliaceaj, 442.
Aracea?, or Aroidcas, 485.
Arachnoid, or drenose : cobwebby, i. e
with entangled slender hairs look-
ing like cobweb.
Araliacere, 427.
Arboieous, arborescent: tree-like, in size

or appearance, 101.
Arc/iegdnium (pi archet/onia) : the ana-

, logue in Mosses of the pistil.
Arcuate: curved like a bent bow.
Areola, pi. areola:: spaces marked out

on a surface.
Ar delate: maiked out into definite

spaces.
Arhizal: destitute of root
Aril, unllus: an accessory covering or
appendage of a seed formed by a
growth from the funiculus, hilum,
or placenta after the completion of
the ovule, 321, fig. C03.
Ariilate: furnished with an arillus.
Aril/ode : a false aril, or covering of the

seed appearing like an aril.
Ai (state : furnished with an awn (arista).
Aristolochiaceae, 462.
Arnatto, 392.

Aire'ct : pointing upwards.
Arrowroot, 481, 490.
Arioiv-s/iaped, or arrow-headed : see Sa-
gittate ; fig. 252.
Artichokes, 437.

Articulated: jointed, i. e. separating by
an ai dentation or joint, as most
leaves from the stem in autumn,
or having the appearance of a joint,
92, 163, 173.
Artificial classification, 365, 511.
Artocarpeae, 474.
Ascending : rising obliquely upwards,

102.'
Ascending axis, 72, 91.
Asci : the spore-cases of certain Lichens

and Fungi, 506, 507.
Ascidium : a pitcher-shaped or sac-
shaped leaf, 169.
Asclepiadaceae, 458.
Ashes of plants, 58, 174. 186.
AspergCHiform : shaped like an aspercjil-
Ivs, or brush used to sprinkle holy
water, as the stigmas of most
Grasses.
Assafoetida, 427.

Assimilation, 19, 21, 61, 177, 190.

Assurgent: same as ascending.

Atropous or ah opal (ovules) : same a»
orthotropous, 298.

Attar of Boses, 417.

Attenuate: tapering gradually to a thin
or narrow extremity.

Augmentation of parts, 242.

Aarantiacexe, 401.

Aurkulate : cared; furnished with au-
ricles or small lobes at the base.

Automatic movements, 347.

Ava, 469.

Avocado Pear, 467.

Aid-shaped : narrow and terete, or near-
ly so, and tapering to a point ;
166.

Awn : a bristle-shaped appendage, like
the beard of Barley, &c.

Aivned : see Aristate.

Axil (arllla, the armpit) : the angle be-
tween a leaf and the stem, on the
upper side. 97.

Axile, or axial : belonging to the axis,
, 292.

Axillauj: belonging to or growing in
the axil.

Axillary buds, &c., 97, 210.

Axis : the stem and root, 67, 72 ; tho
central line of any body, as the

Axis of inflorescence, 211.

Baccate: berry-like ; of a fleshy or pulpy

texture like a berry (bucca), 311.
Balm of Gilead, &c , 407.
Balsams, 145, 407, 414, 480.
Balsamifluae, 425.
Balsaminacerc, 403.
Banner : same as vexillum, 253.
Barbate : bearded ; bearing tufts, spots,

or lines of hairs.
Bdrbellate : beset with short and stiff

hairs, like the pappus of Liatris

spicata, &c
Barbe'llulate : a diminutive of the last.
Barberrv, 384.
Bark, 120, 126.
Barley, 498.
Basal': belonging or relating to the

base of an organ.
Basellaceae, 464.
Basi'dia : cells of the fructification of

Mushrooms, &c, which bear the

spores, 507.
Bds>' fixed : attached by the base.
Basilar : seated on the base of anything.
Bassorin, 55.
Bast, or bass, 400 : bast-cells or tissue,

44, 120.
Bauericre, 425.
Bavbcrry, 477.
Bdellium, 407.

GLOSSARY AND INDEX.

525

Beaked : ending in a prolonged narrow
tip.

Bearded: beset with hairs, especially
stiff or Ions hairs Beard is some-
times used for awn.

Bell-shaped: having the shape of a bell;
277, fig 456.

Benzoic Acid, Benzoin, 443.

Bcrbeiidaccaj, 384.

Bergamot. 401

Berry : a fruit fleshy or pulpy through-
out, 311.

Betel, 469.

Betulaceas, 477.

Bi- (or bis), as a prefix, means twice, as
in the following :

Biacummate : two-pointed.

Btmticidate : two-jointed.

Biauriculate : two-eared.

Bibidcteate: with two bracts.

Bibructeolate : with two bractlcts.

Bicd/lose : bearing two callosities or lit-
tle protuberances.

Bicipital. : having two stalks or legs, as
the keel of a papilionaceous coiolla,
fig. 392.

Biconjitfiate : twice-paired, as when the
petiole of a compound leaf forks
twice.

Bicornule : two-horned.

Btde'iitate : having two teeth (not twice
dentate or doubly toothed)

Biennial: lasting more than one year,
but not more than two years, 83.

Bifarious : two-ranked ; arranged in two
vertical rows.

Bifid: two-cleft to the middle or there-
abouts, 159.

Bifioious: two-flowered.

Bifoliate : two-leaved.

B'fdtiolate : of two leaflets.

Bifurcate: two-forked, or, sometimes,
twice-forked

Bif/e'm mate : t w i ce-pa i red .

Biyener : a hybrid between two plants
of different genera

Bignoniaceue, 447.

Bijugate : a pinnate leaf with two pairs
"of leaflets

Bilabiate : two-lipped, 255, 258, 278.

Bildmellnte, or bi lamellar : of two plates
or lame'i/ie.

Bilberry, 439.

Bdobaie, or bilobed : two-lobed, 159.

Bddcular : two-celled.

Binary : the parts in twos, 239.

Binute : in twos ; produced or borne in
pairs, 164.

Binomial nomenclature (of two names),
363.

Bipartite : two-parted.

Bipinnate: doubly or twice pinnate;
164, fig. 282."

Bi pinnate! y : twice pinnately, 161.

Bipinndtifkl • doubly or twice pinnati-
fid; 161, fig. 280.

Bipinndtiscct : twicc-pinnatclv divided,
161.

Biplicate : twice folded, or having two
folds.

Biporose: opening by two small holes
or pores, fig. 474.

Biiadiate : consisting of two n>ys.

Birdlime, 469.

Birimose : opening by two slits, as do
most anthers, fig. 473.

Bise'ptate: having two partitions.

Bise'rial, or bise'n'ate: occupying two
rows, one within or above the other

Bise'nate : doubly serrate, i c. the teeth
themselves serrate.

Bisexual : having both stamens and pis-
tils, 261.

Bisuh-ate : having two furrows.

Bite'inate: twice ternate ; i. c. divided
into three parts, and these again
into three; 164, fig 284.

Blackberry, 416.

Bladder// : thin and inflated, like a blad-
der.

Blade of a leaf, petal, &c, 145, 276.

Bloom, 56, 144.

Blueberry, 439.

Boat-shaped : concave within and con-
vex (and often keeled) without.

Bohon-Upas, 475.

Borraginaccae, 450.

Bothre'nchyma, 45, 46.

Brdchiate : witli opposite branches, the
successive pairs spreading at light
angles with each other.

Bract (Latin, biactea) : the leaves of an
inflorescence, especially the leaf
which subtends a flower, 143, 211.

Brdcteate : subtended by a bract.

Brdcteolate : subtended by

Bructlets, bract ioles (Latin, biacte'ola;) :
bracts of a second order, &c, or
bracts on the pedicel or the flower-
stalk, 211.

Branches, and branchlets, 97.

Brazil-wood, 414.

Bread-f'iuit,475.

Breathing-jioies, 52, 150.

Bristles': stiff short hairs (52), or hair-
like bodies.

Bristly : beset with stiff bristles.

Bromeliaceas, 492.

Bnjdloqy : same as Muscology.

Buckwheat, 466.

Bud: a stem or branch in an undevel-
oped state, 93.

Budding, 100.

Bud-scales, 95 167.

Buff.ilo-bcrry, 468.

526

GLOSSARY AND INDEX.

Bulb: a pcrmnncnt bud with fleshy
scales, mostly subterranean, 109.

Btdbtfeious : pioducing bulbs.

BtillJcts : little bulbs above ground, 109.

Bulbose, or bulbous: bulb-like in shape.

Bulbo-tubei : same as a corm.

Bui/ate: a surface appealing as if blis-
tered, puckered, or bladdery (fiom
bulla, a bubble).

Burmanniaeca?, 490.

Bnrseracese, 406.

Bui siculate : provided with pouch-like
appendages (bursicuke).

Butomacea?, 487.

Bntttrfly-shap»d corolla, 253. 277.

Butternut, 476

Bi/ssaceous : composed of tine entangled
threads (byssus, or line flax).

ByttneriacesE, 398.

Cabombacea?, 386.

Cactaecac, 421.

Caducous: falling- off" at the time of
expansion, as the calyx of the
Poppy, 279.

Csesal pincai, 413

Ciesious : lavender-colored.

Coisjii/o.se, or cespitose : growing in tufts
or turfs.

Cajeput oil, 418.

Calabash, 417."

Calabash-Nutmeg, 383.

Culatliidium : a name for the head of
Compositaj.

Caldtlafonn : cup-shaped.

Calcinate : bearing a spur (ca/car), 278 ;
as the Violet, fig. 396, and Lark-
spur, fig 398.

Cdlcfolate, or cdlaform, slipper-shaped.

CallitriehacesB, 470.

Callose: furnished with callosities (cal/i)
or hardened or protuberant spots.

Odious: bald.

Calycanthacere, 417.

Cd/i/cine : relating to the calyx.

Calycnhite, or ctdicuhite : furnished with
an outer accessory calyx ( calyculus),
or set of bractlcts resembling a ca-
lyx, as in Dianthus.

Cahjjitia : the hood or veil of the spore-
case of a Moss, 503, 504 ; or a bodv
like it, 389

Cttlyi'tiate : furnished with a calyptra,
or something like it.

Cahj/'trifoiiu : shaped like a calyptra or
candle-extinguisher, as the calvx
of Eschscholtzia, p. 389, fig 692"

Calyx: the exterior floral envelope, or
leaves of the flower, 222, 274.

Cambium, Cambium-layer, 122.

Camelliacca?, 400.

Campanulas a?, 138.

! Campdnulatc : bcll-shapcd ; 277, fi^.
456.

Camphor, 400, 467.

Cauij>ylosi>e'niious : when a seed or seed-
like fruit is lolled up so as to form
a longitudinal furrow down one
side, as that of Sweet Cicely

Cam/ii/lol) o/ious or raiiipyfdtropal ov ulc or
seed. 298, 299, fig. 527.

Canada Balsam. 480.

Canaliculate : longitudinally channelled.

Cdncellate: resembling lattice-work.

Candleberrv, 477.

Canesrent: whitened or hoary with fine
and close pubescence.

Cannabincaj, 475.

Cannacea;, 490.

Caoutchouc, 57, 4 58, 473, 475.

Capers, 391.

Capillary, or capilldceous : hair-like.

Capitate: headed; having a globular
apex like the head of a pin ; or col-
lected into a head.

Capile/late : diminutive of capitate.

Ca/n'/ii/iini : a head of flowers, as of
Clover, Button-bush, &c. ; 213, fig.
320

Capparidacca?, 391.

Capico/ale : furnished with tendrils.

Caprifoliaccre 431.

Capsular : relating to a

Capsule : an v compound dehiscent fruit ;
315, fig". 582, 583.

Cardamom 490.

Carina : a keel ; the two anterior petals
. of a papilionaceous flower; 254,
fig. 392. c.

Cdrniate: keeled ; furnished with a pro-
jecting longitudinal ridge along the
under side.

Caiidpsis, or carydpsis : a grain, 314.

Cannons: flesh-colored

Caruose : fleshy in texture.

Caipd [cm pel Cum or caipidium) : a sim-
ple pistil, or one of the elements of
a compound one, 290.

Cdipe/laiy : pertaining to a carpel

Cuijioluyy: the depaitment of Botany
that i elates to fruits.

Cdipoplioie: the stalk of a pistil, 267.

Carrot, 426.

Cartilaginous: tough, like cartilage.

Cdi uncle: an excrescence at the hilum
of certain seeds, 322.

Caninculatp : furnished with a caruncle.

Caryophyllaceaj, 395.

Caryoplii'/l/actous (corolla) : pink-like,
276.

Carydpsis: a grain, 314.

Cascine, 198.

Cashew, 406.

Cassava, 472.

GLOSSARY AND. INDEX.

i27

Cassia-Irak, 4G7.

Castor-oil, 472.

Castrate (stamen) : with no anther or
one containing no pollen.

Catapetalous : where the petals arc unit-
ed with each other at the base and
with the base of the stamens, as in
the Mallow family.

Catechu, 414.

Cute'nulute: composed of parts united
end to end, like the links of a chain.

Catkin: see Anient, 213.

Caudate: tailed or tail-pointed.

Caudex, 101.

Caudicle : a little stalk, like that of the
pollen-mass of Orchis, &e , fig. 1 235

Caulescent : obviously having a stem.

Cjulicle : a little stein, or a rudimentary
stem ; the radicle, 7 1 .

Caulinr, or caulinar: relating to a

Caiilis: the main stem, 91.

Cayenne pepper, 450.

Cedrelaceai, 401.

Cedi-on, 405.

Celastiacca;, 408.

Cell : a cavity of an anther, ovary, &c ,
281, 291. In vegetable anatomy,
one of the vesicLs, or elements of
which a plant is composed, 23.

Cell-formation, 27.

Cell-growth, 30.

Call-multiplication, 28.

Cellular bailc, or envelope, 121.

Cellular Plants, 63.

Cellular tissue, or structure, 23.

Ci'.llule: same as Cell (in veg. anatomy).

Cellulose, 27, 192.

Celtitbas, 474

Centrifugal inflorescence, 218.
" radicle, 326.

Centripetal inflorescence, 212.
" radicle, 326.

Ccratophyllaccae, 470

Ce'ieal : belonging to corn or corn-
plants ; these having been called
the gift of Ceres.

Cernuous: nodding.

Cuff: the senles or bracts on the re-
ceptacle which subtend each a dow-
er in the heads of many Composiite,
as the Sunflower; also the glumes,
&c of Grasses; 215, 435.

Chaff// : provided with, or of the texture
of chaff

Chaldvi: the part of the ovule where
the coats, nucleus, &c arc all unit-
ed ; 298, fig 521, (/, 526, C

Channelled : see Canaliculate.

C laraceaj, 510.

Ciaructeis : the essential marks distin-
guishing one species, genus, &c.
fiom t'iosa most resembling it, 362.

CharUwcous : of the texture of paper or
parchment

Chcckerbcny, 441.

Chenopodiaecae, 4 64.

Cherry, 417.

Chestnut, 477.

Ch/di oplujll : leaf-grccn, 58.

Cidonisis: a loss of color; a reversion
of the petals, &c. of a blossom to
green leaves.

ChlorospermciE, 500.

Chocolate, 398.

Chdrisis: the division of one organ into
two or more, 2 43.

Chroinule: the coloring matter of plants,
especially of petals, &c.

Chrysobalanaceue, 415.

Cicatrix ; a scar left by the fall of a leaf
or other organ

Cdia (sing cilium, the eyelash) : hairs or
bristles fringing the margin of any-
thing ; those of the inner peristome
of a Moss, 502

Cdiate : the margin fringed with hairs.

Cinchona, 432.

Cinchoneae, 432.

Cine'nelajina, 49.

Cineieous, cinetaceous : ash-gray.

Cinnamon, 467.

Circinate : involute from the top; 144,
fig. 219.

Circulation in cells, 31, 178.

Circttmcissde, or circumscissile: opening
or divided by a transverse circular
line; 317, fig. 588.

C'hcuiuscription : the general outline.

Cm hose, cirrhifeioits: tendril-bearing,
or with organs serving as a

Cin litis : a tendril.

Cistaccaj, 393.

Cisldma : a kind of sac lining the cham-
ber under a stoinate in certain
plants

Classes, 360.

Classification, 352.

Clathrate : latticed.

Clavate,clavifonn: club-shaped; narrow
below and thickened towards the
summit.

Claviculute: with tendrils, or leafstalks
acting as such (clauicuke).

Claw: the nan-owed base of a petal,
&c, 276.

Cleft : cut to about the middle, and with
narrow or acute sinuses ; 159, fig.
261, 265

Climbinrj : rising by laying bold of oth-
er objects in nny way, 102.

Clindiitlunin : the receptacle of the flow-
ers in Composite.

Cloves, 418.

Club-shaped: see Clavate.

528

GLOSSARY AND INDEX.

Olusiacc*, 400.

Clusteud : collected into a bunch.

Giypeate : buckler-shaped.

Coace'rvate : heaped together

Coddunute: cohering ; united at the base
or farther.

Coalescence, 249.

Coidescent : growing together.

Conrcttite : crowded together.

Coaled: composed of layers; or fur-
nished with a rind.

Cobwebbxl, or cobwebby : bearing long
hairs like cobweb or gossamer.

Cocculus Indicus, 384.

Coccus (pi. cocci) : anciently a berry;
now used for the closed carpels into
which many fruits split (316), as
those of Euphorbia, fig. 1U3, 1145,
and Verbena, fig. 985

Cochledi /form : shaped like a spoon (coch-
lea/ ) .

Cochleae : like a snail-shell (cochlea).

Cocoa-plum, 415.

Ctelospc'rmous : i c. hollow-seeded ; the
top and bottom incurved, as in Co-
riandcr-sced.

Coffee, 433.

Coherent: united together.

( 'ohesion of parts, 250, &c.

Coleorhizn (root-sheath) : the sheath or
covering (belonging to the cotyle-
don or plumule) through which the
radicle of most Endogens bursts in
germination.

Collai, collmn : the neck or line of junc-
tion between the pi imaiy stem and
root.

Collective fiuits, 318.

Colocynth, 423.

Coloied: of some other color than green.

Columbo-root, 38-1, 457.

Columella : the axis, or central column,
of a pod or spore-case.

Column : the united filaments of mon-
adelphous stamens, or the united
filaments and style in gynandrous
flowers ; 281, fig. 468.

Columnar : pillar-shaped.

Coma: a tuft of any sort, especially a
tuft of hairs on a seed, 321, fig.
602 ; the whole head of a tree, &.c.

<*omate, or comosp : bearing a coma.

Combretaccu3, 419.

Commelynacese, or Commelinacca;. 496.

Commissure: the line of junction of two
carpels ; used mostly in Umbel-
lifjrte, 426.

Common : used as " general," opposed
to partial.

CdmplancUe : flattened.

Complete flowei : having all the kinds of
organs, 222, 238.

Complicate : folded upon itself.

Compositje, 435.

Compound flower, 215, fig. 323-325,and
435, fig. 887, &c.

Compound leaf: one composed of two or
more blades, 1 63.

Compound pistil, 290.

Compound spike, raceme, umbel, &c , 216.

Compressed : flattened on two opposite
sides.

Concentric layers of wood, 112, 123.

Conchiform : shell-shaped.

Concolored : all of one color.

Condiiplicate ; folded together length-
wise, 144. 165.

Cone: see Strobile, 319.

Coiiferruminate: stuck together by their
adjacent faces, as the cotyledons of
Horseehestnut, 327.

Confertid: crowded

Confluent : running together, or blended
into one.

Conformed: similar to; or closely fitted
to, as the skin to the kernel of a
seed.

Congested: crowded together.

Conglobate: clustered into a ball.

Conglomerate : thickly clustered.

Coniferas, 4 79.

Coniferous : cone-bearing.

Conjugate : coupled; in single pairs.

Conjugation, 332.

Connate: united or grown together from
the earliest state, 251.

Connate-pei foliate, 166, fig 294.

Connective, connecticum : the part of the
anther connecting its two cells or
lobes, 281, 282.

Connii-ent: converging.

Conoidal: approaching a conical form.

Consolidated: when unlike parts are
grown together.

(Consolidation, 250.

Continuous : not intciruptcd.

Contorted: twisted, 272.

Contortiiplicate : twisted and folded.

Contracted : cither narrowed or short-
ened.

Contraiy : opposite in direction to some-
thing it is compared with, as the
pod of Shepherd's Purse flattened
contrary to the partition.

Cdnvolttte (rolled up) or cdnvolutive aesti-
vation, 272.

Cdnvolute vernation : rolled up length-
wise in the bud, 144.

ConvolvulaceoD, 454.

Copaiva, 414.

Copal, 414.

Copalehc-bark, 434.

Cordate: heart-shaped ; shaped like a
heart as painted upon cards, the

GLOSSARY AND INDEX.

529

sinus, or notched end, being at the
base; fig 244.

Couliaeeae, 451.

Coi uiceoiis : of a leathery consistence.

Cork, 477.

Corky : of the texture of cork.

Coi Li/ em-elope or layer of the bark, 121,
127.

Corm (corimis) : a solid bulb, 108.

Connopliytes : plants having an axis
(root and stem), in contradistinc-
tion to Thallophytes,371

CornaccoR, 428.

Corneous: of the consistence of horn.

Corniculate: furnished with a small
horn.

Comine, 428.

Comiite: furnished with a horn (corrrn)

Corolla : the inner of the two floral en-
velopes, 222, 275.

Coro/ldceous, cdiol/ine : like a corolla in
appearance or texture, or belong-
ing to the corolla.

Corona : a crown, such as the append-
age at the top of the claw of the
petals of Silcno; 246, fig. 378.

Cownale: bearing a crown.

Coi lex: the baik or rind.

CortUal: pertaining to the bark.

Coi lirate : furnished with a distinct rind

Cdiymh: a convex or flat-topped flower-
cluster, 211.

Cdiymbose: disposed in, or resembling,
corymbs.

Cost n : a rib, or midrib.

Cos/ate : ribbed, or with a midrib.

Cotton, 44, 398

Cotyledons: the first leaves of the em-
bryo; seed-leaves, 71,324.

Co'ylifoim : dish-shaped.

Coumaiin 414.

Cowitch, 415

Ci aiibcrrv, 439.

Crassnlaceae, 423.

Ciate'iiform : goblet-shaped.

Cieepinij: running on or beneath the
ground and looting, 102

Cieinocmp : the fruit of Umbelliferse,
425.

Crenate, or crenelled : the margin fur-
nished with even and rounded
notches oi scallops ; 159, fig. 256.

Cie'nulute: diminutive of Crenate.

Cresccntftffi, -147.

CusUd: see Cristate.

Crtbiose: pierced with holes like a
sieve

Crinite : bearded with long hairs.

Crispate: curled.

Cristate : crested ; bearing any elevated
appendage on its sin face."

Cioss-breids : individuals oiiginatcd by

4')

fertilizing one variety or species by
another,' 356, 357.

Crowberry, 474.

Gown (246, 279, fig 378) : see Corona.

Ciowned: sec Coionate.

Ci owning: borne on the apex of any
organ.

Cruciate, or cruciform : cross-shaped,
277, as the corolla of the Mustaid
family, fig. 405.

Cmciferse, 389.

Ciude sap, 53, 190.

Crustaceoiis : crusty in texture, hard
and biittlc.

Cryptogamia, 513.

Cry/ildt/aiuous or cryptogam ic : relat-
ing to

Crvptogamous Plants, 69, 330, 499.

Crystals, 59.

Lucullate, or ciicullifoim : hooded or
hood-shaped ; rolled up like a cor-
net of paper, 503.

Cucumber, 423.

Cneuibitaccaj, 423.

Culm: a stiaw, or straw-like stem, 101.

Cultrate: shaped like a broad knife-
blade.

Ciineale, or cuneiform : wedge-shaped ;
broad above, and narrowed to the
base,- with straight sides ; fig. 235.

Cunoniaceaj, or Cunonieae, 525.

Cnprcssincaj, 480.

Cup-shaped, cupulifoim : hemispherical,
and hollow above

Ciipulate : furnished witli a

Cupule, or cupula : the acorn-cup, 314.

Cupulifcise, 476.

Cwled: ii regularly folded and crimped.

Currant, 421.

Cuirmerved, 158. fig 236.

Cm vi serial: in curved ranks, 141.

Cuscutea?, or Cuscutinea', 4 55

Cushion : the swollen base of a leaf-
stalk, or the enlargement below the
inscition of many leaves.

Cuspidate : tipped with a cusp, or sharp
and rigid point ; 162, fig. 275.

Custaid- Apple, 382.

Cut: see Incised, or J)issected.

Cuticle : the outer skin or pellicle of the
epidermis, 14 9.

Ci/a'lliifbim : enp-shaped.

Cycadacco;, 481.

Cycle : one complete turn of a spire ; a
circle.

Cyclical : roiied into a full circle.

Cycldsis : circulation in cells, 31.

Cyliiidiacous: approaching to the

Cylindrical: circular in transverse out-
line and tapering gradually, if at
nil, as in most stems.

Cymbic/oi in : boat-shaped.

530

GLOSSARY AXD IXDKX.

Cyme, (ryma) : a cluster of centrifugal

inflorescences, 218.
Cymose : bcai ing cymes, or cyme-like.
Cymule (cijinula) : a ajmelet, or little

cyme, 218.
Cyncm hod turn: suchafiuit as that of

Rose (fig 429) and Calycanthus,

fig. 815,819.
Cypcraceaj, 49G.
Cyjaela : an achenium with an adher-

ent calyx-tube, as in Composite.
Cystidtum: a utiicle.
Cijitolithes, GO
Cyiolildst : the nucleus of a vegetable

cell.

Dammer Pitch, 400.

Deca-, in words of Greek derivation :
ten ; as in

Dccagynia, 515.

Decdyijnous : with ten pistils or styles.

Decdmeions : the parts in tens, 2.34.

Dccaiultia, 512.

Decdndious: with ten stamens, 2S0.

Derape'talous : with ten petals, 276.

Deciduous : falling off. or subject to
fall ; as petals falling after blos-
soming, 279, and leaves before
winter, 172.

Dec/mate, declined: turned to one side.

Decompound: several times compound-
ed, 1G5.

Decumbent: reclined on the ground, the
summit rising, 102.

Decunent: prolonged below the inser-
tion, as the leaves of the Thistle,
170.

Decussate: the successive pairs crossing
each other at light angles, 142.

Deiluplication (dedonblemenl), 243.

Defiwle : of a fixed number, and not
above twelve or twenty.

Definite (powth, 100.

Definite injlo) escence, 217.

De flexed : bent downwards.

Dfioiate: past the flowering state.

Defoliate : having east its leaves.

Dehiscent futits, &c , 315 ; opening by

Dehiscence : splitting, as do pods,3 11,316.
" of anthers, 283.

Deliquescent : the stem dissolving into
brandies, 99.

Deltoid: shaped like the Greek capital A

Demerged: growing under water.

Dendioid, dendnlic: tree-like.

Dentate : same as toothed ; 1 59, fig. 255.

Denticulate : furnished with fine teeth, or
denticulations

Denudate: made naked.

Dopaiipemte : dwarfed in size.

Depressed: flattened vertically or from
above.

Descending: tending gradually down-
wards.

Descending axi*, 72, 79.

Dcsmidite, or Dcsmidiaceaj, 510.

Determinate inflorescence, 217.

Descriptive Botany, 15.

Development, 19.

Dextrine, 54, 193.

Dexlioise: towards the right.

Di-, in Greek compounds ; two.

Diadclphia, 513.

Diadelphous : stamens united by their
filaments in two sets ; 280, fig. 4G1.

Diandria, 512

Didndious: with two stamens, 279.

Diagnosis: a brief essential character.

Dialype'talous : of distinct petals.

Diapensiaceoe, 454.

Diaphanous : transparent.

Diatomaceae, 510.

Dicdipellury : of two carpels.

Dichlamydi ous : with both calyx and
corolla.

Dichondrcre, 4 55.

Dichdlomous : forking into two branches.

Diclinous: with the stamens and pistils
in separate blossoms, 261.

Dicdecons : separable into two cocci.

Dteotiflc'donons : having a pair of cotyle-
dons, 78, 326

Dicotyledons, Dicotyledonous Plants,
114, 326, 370.

Dichpnous : twin.

Didvnamia, 512.

Didynamous: with two long and two
shorter stamens, 258, 281.

Di (formed: of unusual shape.

Diffuse: widely anil loosely spreading.

Diqamous : having flowcis of two dif-
ferent sexes.

Digestion, 190.

Dujitnte (fingcicd) : compound, with the
parts all arising from the same
point ; 163, fig. 277.

Digitate!*] tri-pluiifoliolatc, 164.

Digynia, 515.

Dirppious : with two pistils or styles, 287.

Di'llcniaccte, 380.

Dimeious: the parts in twos, 234. 239.

Dimidiate: halved, or appearing as if
one half or side were wanting, 2S3.

Dimorphous: of two forms.

Dkecia, 513.

Diacious : with stamens and pistils in
separate blossoms on different
individuals, 2G2.

Dioscoveacctc, 492.

DiosmeotJ, 407.

Dipelalous: of two petals, 276.

Diphyllous : two-leaved, 275

Diploste'monous: stamens double the
petals or sepals in number.

GLOSSARY AND INDEX.

531

Dipsaccm, 435.

Dipterocarpcre, 400.

Dipterous : t\\ o-winged.

Disciform : disk-shape ; flr.t and circu-
lar, like ii disk or quoit.

Discoidal, discoid: like a disk; or be-
longing to the disk ; destitute of
rays, 436.

Dise'pu/otts • of two sepals.

Disk, or disc : a fleshy expansion of the
receptacle of a flower, 267 : the
central part of a head of flowers,
ns opposed to the border, 430 ; the
face of any flat body, as opposed
to the margins.

Dish-bearing woody tissue, 43.

Dish-flowers, 436.

Dissected : cut into pieces, or nearly so.

Dissepiment : the partition of a pod, 291.

Dissident : bursting in pieces.

Distichous: in two vertical ranks, 134.

Distinct : when parts of the same name
arc unconnected, 251.

Divaricate : straddling widely.

Divergent : separating, their summits
inclining from each other.

Divided: cut into distinct portions ;
100, fig. 263, 267.

Dodeca- : in Greek derivatives ; twelve.

Dodccagynia, 515

Dodecdgynous : with twelve pistils or
styles

Dodccandi io, 512.

Dodecdndrous : with twelve (or from
twelve to nineteen) stamens, 280.

Dohibi i form : axe-shaped

Dorsal': belonging to the back (dorsum).

Dorsal sut me, 280.

Dotted edicts, 38.

Dotted leaves, &.c. : marked with small
spots, cither colored, or transparent
and appearing like punctures.

Double flowers : monstious blossoms,
with the petals unduly multiplied,
222, 229.

Doubly compound, 1G4.

Downy : clothed with soft pubescence.

Dragon's blood, 414, 493.

Droseracca?, 394.

Drupaceous : like or pertaining to a

Diupe: a stone-fiuit, 312

Drupelet: a diminutive drupe, 313.

Dryadcae, 418.

Ducts, 45.

Diuiiose : bushy.

Duplicate : doubled or folded.

Durdmen: heart-wood. 126.

Duxirf: comparatively low in stature.

E-, or Ex-, as a prefix, means destitute
of; as, ecostate, libless; cxalbumi-
nous, without albumen, &c.

Eared: sec Auricnlatc.

Earthy constituents of plants, 179, 186.

Ebenaee.T, 442.

Ebe'neous : black like ebony.

Ebony, 442

Ebi detente: destitute of bracts.

Ebrdcteolate : destitute of bractlcts.

Elurmous: white like ivory.

Echinate : beset with prickles (like a
hedgehog).

Ecliinulitte: rough with small prickles.

Eele'ntate : toothless.

Ejj'ete: past the perfect or productive
state.

Effiisc: very loosely spreading.

Eglandulose : destitute of glands.

Elaborated sap, 53.

Elaiagnaeerc, 467.

E/eiters, 40, 505.

Elatinacca:, 395.

Elementary constituents of plants, 179.

E/ementari/ structure of plants, 17.

Ellipsoidal: approaching the form of

Elliptical: oval or oblong, and with
both cuds similar and regularly
rounded.

Emarginate : notched at the end ; 162,
fig. 273.

Embracing : surrounding, as by abroad
. attachment.

Embryo: the rudimentary plantlet in a
seed, 71.323.

Embryo-sac, 304.

Embrijogeny : the formation of the em-
bryo, 304.

Embryonal vesicle, 306.

Emersed: raised out of water.

Emetine, 433.

Enantiobldstous : with the embryo at the
end of the (orthotropous) seed dia-
metrically opposite the hilum, as in
Tradcscantia.

Endeeagynia, 515.

Eneleceigynous : with eleven pistils or
, styles.

Endocarp : the inner layer of a pericarp,
, 310,312.

Endocluome : the coloring matter of
, Al^ae. »

Endo£cn, Endoaense, Endogenous
Plants, 113, 370, 482.

Endogenous stiucture, 113. 114.

Endoplildum : inner bark, 1 20.

Endoplciiia: the innermost seed-coat.
321.

Endorhiza?. : a svnonymc for Endogens.

Endoihizal: said of an embryo which
has the radicle sheathed by the
cotyledon or plumule wrapped
around it.

Enelotmcisp, or Endosmdsis, 33.

E'ndospiim; the albumen of the seed,

532

GLOSSARY AND INDEX.

especially when this is formed in the
, cmhiyo-sneof thoo\u]e,322, 323.

Endostoma : the oiificc of llic inner

coat cf the ovule, 298.
Endothelium: the inner lining of the

cells of an anther.
Enervtd : nerveless.
Ennea-: nine ; as in
Enneagynia, 515.

Ennedgynous : with nine pistils or styles.
Enneandiia, 512.
Enneditchous : with nine stamens.
Enncapc'talous : nine-pctalled, 276.
Entidul: without a node.
Ensale : same as
Ens- form : sword-shaped
Enlii c : the margin whole and even,

not toothed or cut, 158, 275.
Entophytcs : plants parasitic within oth-
er plants.
Epaciidca-, 440.
Ephemeral : lasting but a day.
Epi-, in Greek compounds : upon.
Epicdfi/x: an involucel resembling an

cxteiior calvx, as in Mallow.
Eplcai p: the outermost layer of a peri-

caip, 310.
Epichutum : the upper part of the lip of

an Orchid, when different from the

lower.
Epicoiollinc : upon the coiolla.
Epidemiol: i elating to t'le
Ejiicleimis: the skin of a plant; 51,

122, 148.
Epiyaous : giowing on or close to the

ground.
Epijijuous : upon the ovary, 252, 268,

281.
Epipc'talous : upon the corolla, 281.
Ejuphldbun : outer or corky bark, 121.
Epiphjlloiis : upon a leaf
Epiphytal, or epiphjtic : relating to
E'piphijtcs, plants glowing affixed to

another plant, but not nouiishcd

by it, 87.
Epipteious : winged at the top.
Epispei-in : the outer seed-coat, 320.
Equal: regular, or of the same length

or number, as the case may be.
Equilateral : equal-sided.
Equisetaceae, 499.

E'qmtant : riding straddle, 145, 165.
Erianthous : woolly-flowered.
Ericaceae, 439.
Ergot, 498.
EiiocaulonaccDS, 496.
Eriogoncaj, 466.
Eiose: eroded, as if gnawed.
Erdstrale: not beaked.
Escalloniese, 425

Essential organs of the flower, 222.
Estivation: sec ^Estivation.

Etaiiio: a name for such a fruit as a
raspberry and blackberry.

Euphorbiaeia?, 471

Enilnd, or evdlvulen : valvclcss.

Evtrgreen : holding the lea\ es over win-
ter or longer, 172

E. r album i nou s : without albumen, 323.

Excentnc: out of the centre, 325 ; one-
sided.

Excretions, 57, 1 78.

Excwrent : protnuling beyond the apex,
as when the midiib of a leaf jno-
jects : or running to the very sum-
mit, as the main stem of a Fir, 99.

Exhalation, 175.

E'xocmp : the outer layer of a pericarp,
, 312.

Exogcn, Exogcnce, Exogenous Plants,
113, 370.

Erogenous stiucturc, 113, 116.

Exorhi/ai: a synonymc of Exogens ;
the radicle in these being

Eroilii-al: not enclosed or sheathed
by the cotyledons or plumule.

Erosmdse, or Exosmdsis, 33.

E'xostoine: the oiificc of tbc outer coat
of an ovule, 298.

Exostosis: an indurated protuberance.

Erot/ifcntm : outer coat of the anther.

E'xplanate : outspread or broadly flat-
tened.

Exserted, exse'it : protnuling beyond, as
the stamens out of the coiolla in
fig. 450.

Exstipidate : destitute of stipules, 171.

Exterior: as applied to the paits of a
blossom, the same as anterior.

Extine: the outer coat of a pollen-grain,
286.

Extra-axillary : out of the axil, 99,
220.

Extroise : turned outwards, 282.

Fades: the general aspect.

Falcate, falcifoi in : scythe-shaped ; flat
and curved, the edges paiallel.

Families, 359.

Fan-shaped : see Flabclliform.

Faiina : starch, 54

Farinaceous : mealy; containing starch.

Fdnnose: covered with mealy powder

Fdsciate: banded; applied also to mon-
strous steins which grow flat.

Fasciation : the singular monstious ex-
pansion of stems, &c. as in the gar-
den Cock's-eomb.

Fascicle: a close cyme or cluster of
flowers, 219; "a bundle of leaves
crowded like those of the Larch,
fig 213.

Fascicled: growing in tufts or clusters,
84, 142.

GLOSSARY AX1) I XI) EX.

533

Fasciculate: in small tufts.

Fasti /kite: close, parallel, and upright.

Faux (pi. fauces) : the gorge or lliro.it.

Fdveolate, fill ose : with deep pits, like
honeycomb.

Feathcr-vc iud : having veins all pro-
ceeding from a midrib, 155.

Feathery : see plumose.

Fe'cula: starch, 54.

Female flower : sec Fertile flower.

Fene'shute: pierced with one or more
holes, like windows.

Ferriu/ineous or /en uginous : of the color
of iron-rust

Falde: capable of producing fruit.
Stamens arc also said to he fertile
when their anthers contain good
pollen.

Fati/e flower: one having pistils,

20 r.

Fertilization, 300.

Filne, 41.

Fibril: a delicate fibrc-liko body; the

loot-haiis, 81.
Fihidifonn tissue,, 48
Fduil.'os'.: healing fibrils : diminutive

of fihious.
Fibrinc, 198.
Fibious or, fibrose: composed of slender

threads or libics.
Fibro-vuscular tissue or system, 50.
Fiddle-shaped: obovatc and contracted

on each side.
Fig, 215, 475, and fig. 590-592.
Filament: tlic stalk of an anther, 223,

281. Or any slender thread.
Filamentous, or Jilmuentose : composed

of tin cads or filaments.
Filiccs (Ferns), 500.
Fthco/oj'j : the part of Botany which

treats of Feins.
Filiform: shaped like a thread ; slender

' and terete, 1G6.
Filijie'iiclii/ous : hanging fiom a thread,

as the tuberous roots of Spiraea fili-

pcndula.
Fimbi iate : fringed ; bordered by slen-
der processes or appendages.
Fimbiillate or flinbrillifetous: diminu-
tive of the last.
Fingered: sec Digitate.
Fissiparoits : propagating by division

into two portions.
Fistuhir or Fistidose: hollow through

its length, as the leaves of Onion.
Fldbellate, or flabellifoi in: fan-shaped;

bioadly wedge-shaped with the

summit loundcd.
Flaeourtiaeea>, 392.
Flagellate: l>eaving flagella, i. e. runners,

like those, of the Strawberry.
Flage'llform : long, taper, and supple,
45*

like the thong of a whip ; runner-
like.

F/aveseent : yellowish or pale yellow.

Flaunts : vellow.

Flax, 402"

Flesh i/ : succulent, or of the consistence
of flesh, 84.

Fle'xuose, or flexuous : zigzag ; bent alter-
nately inwards and OiUwaids.

Floating: growing on the siufacc of
water.

Floccose: bearing or clothed with locks
of soft hairs or wool.

Floia (the goddess of flowers) : the ag-
gregate of the species of plants of a
country ; or a work systematically
describing them.

F/oial: belonging to the flower.

Floud invelopes: flower-leaves, 222, 2G8

Fi'ou-scence: same as anthesis.

Floret : a small flower, or a separate
blossom of a so-called compound
flower.

Floridcas, 509.

Floiifaous : flower-hearing.

Fldsculous: composed of or bearing flos-
culi, i c. florets ; or composed of
tubular flowers only.

Flower, 70, 221.

Flower-bud, 209, 224.

Flowering, 204.

Flowering Plants, G9, 3C9, 375.

Flowcrless Plants, G9, 330, 499.

Fluitant: floating on water.

F/iiciali/e: belonging to flowing water.

Fly-traps, 168.

Foliacfotts: leaf-like, i. c. thin, membra-
naceous and green ; or bearing
leaves.

Foliar: belonging to leaves (folia).

Foliation : leafing out

Foliate : clothed with leaves ; or, with a
numeral prefix, denoting the num-
ber of leaves ; as, bifoliate, two-
leaved : trifoliate, throe-leaved, &c.

Fdliolate: consisting of leaflets (fo-
liola) ; as, bifoliate, a leaf having
two leaflets, or trifoliolale, having
three leaflets, &c.

Fdliose: bearing numerous leaves.

Follicle: a simple pod opening down
one side ; 315, fig. 579.

Follicular, of the nature of a follicle.

Foramen : an aperture or orifice, 298.

Foiaminulose: pierced with small holes.

Fdreipate: forked like a pair of pinccis.

Foiled: branching into two or more-
divisions

Fornicate: arched over, bearing a

Fornix, pi. fdmices: little arched scales
in the tin oat of a corolla, as in
that of lIoa:id's-tonguc.

534

GT.OSSAUY AND 1XDKX.

Fdveafe : pitted, having fovea or depres-
sions of the sin face.

Fdrcojate : marked with little pits or de-
pressions ( fovc'ohe).

Fovulce: minute particles in the fluid
contained in pollen, 23G.

Fice: separate; not united with dis-
similar parts, 250.

Fringed: sec Fimbriate.

Fioncl: the foliage or Ferns (500),
Liverworts (504), &c., G7.

Fi ondesrencc : the act of leafing.

Frondose: leafy, or more commonly it
now means frond-like, or producing
a fiond instead of ordinary foliage,
504.

Fructification : fruiting, or the fiuit and
what attends it.

Fructification, organs of: the stamens
and pistils.

Fruit, 308.

Fiuit-dots, of Ferns, 501.

Fi umentuccous : producing starch, or re-
lating to corn (fumentum).

Fi itstulose : consisting of small portions
or fragments.

Frutescent : becoming shrubby.

Fruticulose : very small and shiubby.

Fi ilticosc : shrubby ; relating to a

Frulex : a shrub.

Fucacea1, 509.

Fugacious: falling off or perishing very
early, as the calyx of the Poppy,
and the corolla of Cistus ; 172.

Fulci ate : belonging to or fui nished with
fulcra (props), i. c. with append-
ages such as tendrils, prickles, stip-
ules, &c.

Fuliginous, or fuliainose : sooty ; dark
and dee]) brown.

Falcons : tawny : orange-yellow mixed
with gray.

FumaiiaceiB, 389.

Fundamental organs, 70.

Fungi, 507.

Fung form : mushroom-shaped.

Fnngiilform : diminutive of the last.

Fnmjose : spongy in texture.

Funiculus: the seed-stalk, 297,321.

Funnel-shaped, funnel foi in : see Infun-
dibuliform, 277.

Furcate: forked, the forks spreading.

Fiuf nacrous : scuify.

Fun owed : sec S ul catc.

Fusions : grayish-brown.

FiUufmm /spindle-shaped ; 84, fig. 13S.

Fustic, 475.

Galbanum, 427.

Galhulns : a fleshy and closed strobile
imitating a bciry, as a Juniper-
be rrv, 320.

Galea : a helmet ; an arched sepal or
petal,' 278, fig. 458.

Giiha'e: having, or shaped like, a hel-
met.

Galingalc, 490.

Galls,'"477.

Gamboge, 400.

Ga'mo/iliij/lous : composed of leaves
united by their edges, 275.

Gamopetalous : composed of united pe-
tals, 249, 275.

Gamose'palous : of united sepals, 249.

Gelatinous coils in cells, 40.

Geminate : in pairs.

Gemma : a bud or growing point.

Gemination : budding growth, 31.

Gc'iiimule : a young bud ; the plumule.

Genera: plural of genus.

General : the opposite of partial ; as the

Gcneial involucre of a compound um-
bel, &c. 216.

Generic: relating to the genus.

Geniculate: bent abruptly like a knee.

Gcntianaccrc, 45G.

Gentianinc (Gentian), 457.

Genus, 358.

Geographical Botany : the study of
plants in respect to their geograph-
ical distribution.

Gcraniacea:, 403.

Get in : the eye of a bud ; or any glow-
ing point ; or an embryo, 323.

Germen : an old name for the ovary.

Germinal vesicle, 306

Germination : growth of the embryo
from the seed, 71, 328.

Gerontoijieoas : belonging to the Old
World.

Gesneiiacece, 44.

Gibbei : an enlargement, or gibbosity
of any sort, on one side of a calyx,
a fruit, &c.

Gibherose or gibbous: swollen or en-
larged on one side.

Gills of Fungi, 500.

Ginger, 490.

Ginseng, 428.

Glabi ou's : smooth, i. c. destitute of hair-
iness.

Gfabiate: smoothed, or becoming near-
ly glabrous.

Glddiate : sword-shaped.

Glands : any secreting apparatus, 52.
The name is also given to any pro-
jection or appendage the nature
and function of which is not obvi-
ous, 264. Glans is also the classi-
cal name of an acorn and chestnut.

Glandular, glandnlifcrons, glandnlose :
healing glands, or gland like in
texture

Glandulai hairs, 52.

GLOSSARY AND 1XDKX.

535

Glandular tcoody tissue, 43.

(Jlaieose: growing in gravelly places.

Glauvescent: verging upon or slightly

Glaucous: covered with a whitish bloom,
which rubs oft', as the surface of a.
cabbage-leaf or a plum, or so
whitened as to appear to have a
bloom, 5G.

Globose: sphcnical or nearly so.

Globular : nearly globose or spheri-
cal.

Gloclndeous, or ejlochidiate : barbed ;
hooked back at the point, like the
barb of a fish-hook, or with two or
more such barbs at the point.

Glometate: clustered into a

Glomerule : a capitate cy me, i. c. a cyme
condensed into a head, 219.

Glossology: the department of Botany
which explains the technical terms
of the science, 15.

Gluniareous : bearing, or resembling
glumes.

Glume : one of the husks or chaff of
Grasses, &c, 497

Glumelle : an inner glume or palea.

Gluten, 197.

Glutinc, 198.

Gdnophore: a stalk elevating both sta-
mens and pistil, 2G7.

Gooseberry, 421.

Gossi/pine: cottony.

Gourd (a pepo), 423.

Giafting, 100.

(7 tain, 314.

Gruminere, 497.

Granadilla, 422.

Granular : composed of grains or gran-
ules.

Granulate: composed of little kernels
or coarse grains.

Gianu/es: any minute particles.

Grape, 408.

Green hu/er of the bark, 121.

Grossulaceue, 420

G 1 unions, or grumose: consisting of
clusteied grains.

Guaiacum, 405.

Guava, 418.

Gum An'uni, 400. Gum Arabic, 414.
Gum Elemi, 407. Gum Traga-
canth and Senegal, 414.

Gutta-percha, 57.

Guttate : sprinkled with colored dots or
small spots.

Gur.iferaj, 400.

Gi/mnocdr/ious : nnked-fiuitcd.

Gymnospcrmia, 315.

Gi/mnospe'rmous : naked-seeded, 296.

Gymnosperms, or Gvmnospermous
Plants, 297, 371, 47*9.

Gyncecium: the pistils of a flower, 223.

Gynandria, 513

Gyndndious : stamens borne on the pis-
til, especially on the stvlc; 253,
2S1, fig 4G8

Gynobase : the base of a stvlc, or sum-
mit of a receptacle, on or mound
which two or more caipcls aie in-
serted, as in Kite, Sage, Geranium,
&C., 2G7.

Gijnophoie: the stalk of a pistil, 2G7.

Gyiate or r/yiose: bent round, or bent
back and forth.

Habit (Habitus): the general aspect of

a plant.
Habitat: the habitation, or situation in

which a plant is naturally found.
Hack ben v, 474.
Hamiatinc, 414.
Hannodoracca;, 492.
Hans, 52.
Hairy: clothed or beset with hairs,

which are separately distinguish-
able.
Halbeid-shaped, or Halberd-headed: see

Hastate.
Haloragcaj, 420.
Halved: see Dimidiate ; appearing as if

one half was absent.
Ilamamelaceie, 425.
Hamate, or hamose: hooked.
Hdmu/ose: diminutive of hamate.
Hastate: halbeid-headcd ; shaped like

a halberd, ^ iz. with a spieading

lobe at the base on each side; 157,

fig. 250.
Hazel-nut, 476.
Head: sec Capituhmi ; 213, fig.

320, &c.
Headed: same as capitate.
Heait-sf taped: see Coidate.
Heait-uood, 35, 124, 126.
Hebetate: blunted, having a soft obtuse

point.
Helicoid : coiled into a helix or snail-
shell, or tending to be rolled up ;

as in Fig. 332.
Helmet: see Galea, 278.
Helobious : living in marshes.
He'lvolous: grayish-yellow mixed with

some red.
Head- in- Greek derivatives : halved or

half; as
Hemi-andtiopous : half-anatropous.
He'micarp : a half-fruit of Umbellifera? ;

same as meiicarp.
Hemitiopal, or hemitiopous : nearly the

same as amphitropous.
Hemp. 475.
Ilcpatico:, 503.
Hepta : the Greek numeral seven, used

in the following compounds.

53G

GLOSSARY AND INDEX.

Hcptagynia, 515.

HtqAdgynous : having seven pistils or

styles.
Heptdineions: the parts in sevens.
Ilcptandria, 512.

Heptdndrous : with scvea stamens, 2S0.
Ihptapc'lalous : of seven petals, 27G.

//<»/-&, 101.

Herbaceous : not woodv ; of a soft text-
ure like an herb, i()l, 102.

Heibaiimn : the botanist's collection of
dried specimens of plants, 518.

Hermaphrodite: bisexual, 2G1.

Hespendium: a firm-iindcd berry like
an oiangc, 311

Ifotero-, in Greek dci ivatives : unlike ; as

lhterocdipons: having two kinds of fruit

1/ettrucc'p/iulotis : beaiing two kinds of
heads ; as in Bacchaiis.

ITeterodrtiinous, 140.

Jleterd/amous : bearing two sorts of
flowers, 436.

Heteioyeneons : of two or more kinds.

lleteiuliopoits, or hetertiti o/ial ', ovule or
seed : same as amphitropous, 300.

IToxa-, in Greek dei ivatives; six.

Ilexagy'nia, 515.

Ilexw/i/ nous: having six pistils or
styles.

Hexdmeions : the parts in sixes, 234.

Hexandria, 512.

Heidndro'is : with six stamens, 279.

Hexape'talous : six-pctallcd, 276.

Ilcxapliu/lous: six-leaved, 275.

Ilerdpteious : six-winged.

J ' lexusepalous : with six sepals, 272.

Jfexaste'inonous: having six stamens.

Hickory-nut, 476

Ihdden-venitd : where the veins aic not
visible, as those of the leaves of
Pinks and Houscleeks.

Hilar: relating to the hilum.

JItlum : the scar, or point of attachment
of the seed, 297, 321.

Hippocastanaceaj, or Hippocastancas,
410

JHppocre'pifonn : horseshoe-shaped.

JJnsitte: clothed with coarse hairs.

Hispid: beset with stiff biistly hairs.

IIouiij : grayish-white fiom a fine pu-
bescence.

Honiorarpotis : bearing fruits all of one
kind.

Hanodi onions, or homoth omal , 140.

Homdqamous: when all the flowcis of a
head, &c. are alike, 436.

Homogeneous : all of the same nature or
structure.

llomo'nyniis : of the same name ; said
of parts which are of the same
morphological nature ; c g. bracts,
sepals, petals, stamens, and sim-

ple pistils arc homologous with
leaves; 225, 231. Sec Analogous.

Homoloyue : an homologous part.

Homdmalloiis (leaves, &c ) : originating
all round an organ, but directed or
curved lound to one side of it.

ITomomorphous : of one form.

Homotiopous, or lio»to!ro/>al. (embryo) :
curved in the same way as the seed,
as in the Chickwccd, tig. 621.

Hops, 475.

Horny: sec Corneous.

Horizontal system, 50, 112.

Hortus Siccus: same as herbarium.

Huckleberry, 439

Hnmifnse : spreading flat on the ground.

Humus, Ilunvie acid, 57.

Hyaline : transparent, or partly so.

Hybrid: a cross-breed between individ-
uals of two species, 357.

Hvdrangica?, 425.

Hydioeharidacese, 487

Ilvdiolcaceic, or Hydroleaj, 452.

IlvdrophvllacciP, 451.

Hydrophyte .- a water-plant.

Hvdiopterides, 502.

Hysmah belonging to winter.

Hymc'iiium : the gills of Mushrooms, &c,
507.

Hvmcuophylleae, 501 .

Hi/pdiithiiini : a naked fleshy receptacle,
like a tig.

Hypericaccre, 394.

Ifypo-, in Gieek derivatives : under.

Hy/ior/ii/iiaa : the under part of the lip
of Orchids, when jointed or other-
wise distinguishable.

Hi/pocKitc'iifbiin, or, more properly,

Hypoci aterimdi phous : salver-shaped ;
i. e with a limb spreading flat at
right angles to the tube; 277, (ig.
457.

Ilyjio/dons, or Iiypor/reaa (flowers or
fruits) : borne under ground, 76,
78, 328.

IL/jid ppiois : growing under the pistil,
and free, 250, 268, 280.

Hypophyllons: growing on the lower
side of a leaf.

Ilysteranthons : plants whosc leaves ap-
pear later than the blossoms, as
the Red Maple.

Hystei nphytnl : living on a matrix, cither
of dead or living organic matter.

Hysterophytts : same as Fungi, &c.

Tcos-, in Greek compounds : twenty.

Icosandiia. 512.

Icosdndrous : having 20 stamens or more

inserted on the calyx, 280. •
Illecebrcffi, 396.
Imbibition, 177.

GLOSSARY AND INDEX.

537

Imbricate, imbricated, (mbricative: over-
lapping, the outer covering the in-
ner, and breaking joints, like tiles
on a roof, 144, 269.

Immarginate : not margined.

Immersed: glowing wholly under water.

Impari-pinnate: pinnate with an odd
leaflet; 163, fig. 288.

Impeifect flowers: wanting either sta-
mens or pistils.

Impregnation : same as fertilization.

Inane: empty.

Incanous: hoary-white.

Incised: cut irregularly and sharply;
159, fig 259.

Included: not projecting beyond; en-
closed.

Incomplete flower: wanting some one or
more kinds of organs, 259.

Incrassatcd : thickened.

Incrustations in cells, 58.

I'ncubous : the apex of each leaf lying
over the base of the next, as in
many Heparicse.

Incumbent: leaning or lying upon :
said of the cotyledons when the
radicle lays against the back of one
of them, 390, 326. fig. 705 ; or
when the anther lies on the inner
side of the filament. 282.

Incurved: bent or curved inwards.

Indefinite: either uncertain in num-
ber, or too many to be readily
counted, 242

Indefinite gi owl/i , 100.

Indefinite inflorescence, 210.

Indeltiscent (fruits) : not opening, at
least not in a legular way, 310, 313.

Indeterminate inflorescence, 210.

India-rubber, 57.

Indigenous : of spontaneous and original
growth in a country.

Indigo, 414, 415.

Individual, 20, 131, 352.

Individuality, 132,352

Indumentum: any hairiness or downy
covering.

IndupUcate : bent or folded inwards,
145, 273.

Indiisium: the proper covering of the
fi nit-dots of Ferns ;. anv peculiar
membranous covering, 501.

Inequdateial : unequal-sided.

Infeiior: underneath, 252; or same as
anterior : thus the inferior petal,
&c. is the same as the anterior one,
237.

Inflated: bladdery.

Inflered: abruptly bent inwards.

Inflorescence, 209.

Infra-at illary : originating below the
axil.

Infundibular, infnndibuliforui : funnel-
shaped ; i. e. a tube enlarging up-
wards ; 277, fig. 1049.

Innate: borne directly on the apex of a
thing, 282.

Innovations : new shoots or new growths.

Inorganic : unorganized.

Inorganic constituents, 179.

Inosculating: opening into each other;
anastomosing, 49.

Inserted: attached to, 224, 250.

Insertion: the place or the mode of junc-
tion of leaves with the stem, &,c,
133.

Inter-, in composition : between ; as

Intercellular : between the cells.

Intercellular spaces or passages, 24, 50.

Intercellular sgstein, 50.

Interlaced tissue, 48.

Internal glands, 51.

Internodes, 92.

Interpe'tiolar : between the petioles, 171.

Interrupted! if pinnate, 164, fig. 285.

Inline: the inner coat of a pollen-grain.

Iiitiafoliaceous: within or before a leaf,
171, as the stipules in fig 305.

Intro flexed : bent strongly inwaids.

Intioise: turned inwards towards the
axis, 282.

Intruse: appearing as if pushed inwaids
or indented.

Inverse: inverted; suspended.

Jiuo'uce'llate: furnished with an

Involuce'ilum, or involucel: a secondary
or partial involucre, 216.

Invo/ucrate: provided with an

Involiicrum, or involucie: an outer or
accessory covering ; a set of bracts
surrounding a flower-cluster; 214,
fig. 321, &c.

Involute: rolled inwards, 144, 273.

Ipecacuanha, 393, 433.

Iridaccae, 490.

Inegular : unequal in size or in shape,
253, 277.

Irregular it g, 253.

Irritability, 345.

Isdcltroiis : one-colored.

Isoelincae, 502.

Isdmerous, or isomeric: the parts equal in
number.

Isoste'monous : the stamens as many as
the petals or sepals.

Jalap, 455.

Jasminacece, 459.

Jelly, 55, 310

Jointed: separate or separable trans-
versely into pieces (joints), 92.

Juba: a loose panicle, ns of Grasses.

Juga: the jidges of the fruit of Umbel-
liforas, 426.

538

GLOSSARY AND INDEX.

Jugcv, : the pairs of partial petioles or
leaflets of a pinnatcly-compouiul
leaf, 104.

JaglandaeciE, 47G.

Jujube, 408.

Ju/us : a name for a catkin.

Julaceoiis : shaped like or resembling a
catkin.

Juncaecce, 495.

Jinicngineae, 4S7.

Jungcrmanniacere, 505.

Juniper-berries, 480.

Jute, 400.

Keel: see Carina, 254.

Keeled: furnished with a keel or sharp

ridge underneath.
Kernel of an ovule, 297, or seed, 322.
Keif fruit, 314.
Kidney-shaped: see Reniform; 157, fig.

245.
Kingdom, 362, 15.
Kinic acid, 433.
Kino, 414.
Knot : see Node, 92.
Knotted: a cylindrical body swollen into

knobs at intervals.
Krameriacese, 412.

Labellum : the lip, or lower petal of an
Orehidcous flower.

Labiatffi, 450

Labiate: two-lipped, 278.

Labiatifloiae, 436.

Lac, 475.

Lacimate: slashed ; cut into narrow in-
cisions ; these are called lacinice.

Lactescent: yielding milky juice.

Ldcunose : full of depressions or exca-
vations (lacdiue).

Lacustrine: belonging to lakes.

Ladanum, 394.

Livvigate: smooth as if polished.

Lane'niform : shaped like a Florence
flask (lagenu).

Lalo, 399.

Lame'/ke: thin plates, like the gills of an
Agaric, 507, &c.

Lamellar, or lamellate : composed of flat
plates.

Lamina (a plate) : the blade of a leaf,
petal, &c, 145,276.

Lanate, lanose : woolly; i e clothed
with soft interlaced haiis.

Lanceolate: lance-shaped ; fig 239.

Lamir/inons: cottony or woolly.

Latent buds, 167.

Lateral: belonging, or attached to, the
sides of an organ.

Latex: milky or proper juice, 49.

Laticiferous tissue or vessels, 49.

Lauraceoe, or Lauiinca:, 466.

Lax: loose; the opposite of close or

crowded.
Lcu/erinrj, 102.
Leaf, 133.

Leaf-arrangement (phyllotaxis), 133.
Leaf-bud, 72, 93.
Leaf-f/reen, 58.
Leafet : a separate piece or partial blade

of a compound leaf, 163.
Leaf-stalk, 145, 170.
Leaf-scurs, 94.
Leathery : sec Foliaceous.
Legume: a fruit like a Pea-pod, 315.
Leguminc, 198.

Lcguminosajf Leguminous Plants), 412.
Leguminous: relating to legumes.
Lcmnacea;, 486.
Lemon, 401
Lentibulaccse, 445.
Lenticels: little spots on the bark, whenco

roots often issue.
Lenticular : lens-shaped ; double-convex.
Lentil ) inose: freckled, or dusty-dotted.
Lepals : sterile transformed stamens.
Lepidute : leprous ; scaly or scurfy, 52.
Leucantlious : white-flowered.
Liber: the inner fibrous bark, 120, 127.
Lid: see Operculum, 502.
Lichcnes (Lichens), 505
Liclieriolocjtj : the part of Botany devoted

to Lichens.
Licorice, 414.

LJgneous : woody in texture.
Li'gninc, 36, 195".
Lignum-vitaj, 405.

Ligulate: strap-shaped, 255; having a
Lnjnle: a strap-shaped corolla, 255, rig.

325, d ; the appendage between the

blade and the sheath of the leaf in

Grasses, 170.
Ligulifloioe, 436.
Liguhforous: when a head consists of

ligulate flowers only, as Cichory,

fig 323.
Liliaccae, 493.
Liliaceous: lily-like, 276.
Limb (l.imbus,a border) ; the expanded

part or border of a corolla, calyx,

&e , or the lamina or blade of a

petal, &c, 145,276.
Limbate: bordeied.
Lime, 401.
Limnanthaccce, 404.
Linacca:, 402.

Line: the twelfth of an inch. (Tn deci-
mal measures, the tenth of an inch.)
Linear: narrow and much longir than

broad? the two margins parallel;

fig. 24 0
Lineate : marked with lines.
Lincofate : marked with fine or obscure

lines.

GLOSSARY AXD INDEX.

539

Linguifbrm, or Ungulate: tongue-shaped,

as t!io leaves of Ilound's-tonguc.
Lip: the two lobes a bilabiate calyx

or corolla; the lower petal of an

Orchidcous plant.
Littoial, or It total: growing on shores.
Lieul : pale lead-color.
Loasacese, 421.
Lobe : any division or projecting part

of an organ, especially a rounded

one, 275.
Lobed, (abate: divided into lobes; rig.

2G0, 2G4.
Lobcliaccae, 438.

Lobttlule: bearing small lobes (lobidi).
Ldcellate: having secondary cells (or

I ocelli)
Loce'llus (plural, (ocelli) : a secondary

cell, or a division of a cell.
Loadament, 316 ; sania as loculus.
L6r.iilar: having cells.
Loculicidal, or loculicide : dehiscence

opening directly into the back of a

cell; 316, fig. 583, 585.
Locuhie: partitioned off into cells, as

the pith of Poke, &c.
Ldcidus (plural, (oodi): the cells of an

ovary, anther, &c.
Locdi'a : a spikelct or flower-cluster of

Grasses
Lddicules (lodicuhe) : the minute scales

inside of the palea; of Grasses, 497.
Loganiacca;, 433.
Logwood, 414.
Loinc.nl: a jointed legume; 315, fig.

581
Lometttaceoits : bearing or resembling a

lament.
Longitudinal tissue or system, 45, 50, 112.
Lonicerca;, 431.
Lorantlia.ca;, 469.
Lorate: thong-shaped.
Lucid: shining

Lunate: crescent or half-moon shaped
Litnnlat.e : diminutive of the last
Lupuline : waxy grains on the scales

of Hops.
Lurid: dingy brown.
Lutexent : yellowish. (Luleus : yellow)
Lycopodiaccaj, 501.
Lycottopous, or lycotropnl : an orthotro-

pous ovule curved into a horse-
shoe form.
Lijrate, lyieshaped, 161, fig. 138, 27s.
Li/iateltf pinnate, 164, rig. 285.
Lythraccue, or Lytharieaj, 418.

Mace: the arillus of Nutmeg, 322, 383
Miculate: spotted or blotched.
Madder. 432.
Magnoliaces, 381.
Mahogany, 401.

Maize, 49S.

}[a(efloicer, 201.

Malpighiaecse, 403.

MaLpitjhiaceous hairs: hairs fixed by

their middle, as ia the foregoing

order, in C'ornus, &c.
Malvaccaj, 397.
Mdmi/late, or mdmiUar : bearing little

prominences on the suiface.
H [dm nice form : teat-shaped.
Mainmce-apple, 400.
Mammoie : bearing larger prominences,

like breasts.
Mango, 406.
Mangostccn, 400.
Manicate (gloved) : covered with a

woolly coat which may be stripped

off whole.
Manilla hemp, 490.
Manna, 460.
Many-cleft : cut as far as the middle

into several divisions, 159.
Many-beaded : sec Multicipital.
Marantaccce : see Cannaccte
Murcesccnt: gradually withering with-
out falling off, 279. *
Marchantiacete, 504.
Marginal : belonging to the margin.
Maiginate : furnished with a margin of

different texture or color from the

rest.
Maritime: belonging to the sea-shore.
Markings on cells, 3, 6.
Marmorale : marbled.
Marsiliaceas, 502.
Mas: male, masculine; belonging to

the stamens.
Masked: see Personate. 278.
Mealy : see Farinaceous.
Medial: belonging to the middle.
Medulla: pith, 118.
Me'dullaig rays, 117, 119.
Medullaiy sheath, 119.
Medullose, or mediitlanj: pitb-liko.
Meioste'uionous : having fewer siarp.Cris

than petals.
Melanospermese. 509.
Mclanthaeea:, 494.
Melastomaceae, 4i8.
Meliaccai, 401.
Melon. 423.
Membranaceous, or membranous: thin and

soft, like a membrane.
Meniscoid: shaped like a meniscus or

concavo-convex lens.
Menispcrmaecaj, 383.
Menyanthideis, 457.
^f^'rlrnr/ll/ma, 4 1.

Me'ricaru: half a crcmocarp, 426.
Merismdtic: dividing into parts, 28.
Me'rithall : a name for an intcrnode
Merous, in Greek compounds : the jmrts

540

GI.OSSAKY AM) 1XDKX.

of a flower: sec Dimerous, Trimc-
rous, &c.

Mcscmbiyanthcmaceic, 397.

Me'socarp : the middle layer of a peri-
carp, 310.

Mesopiddium : the middle baik or green
layer, 121.

M~esoj>/ii/lluiii : the parenchyma of a leaf
between the skin of the two sui-
faccs.

Metamoi pliosed : that which has under-
gone.

M'etamorphosis ■ the transformation of
one organ into another homologous
one 223, 231.

M'wrop'/lr: the oiificc of a seed, 29S.

Midiib: the ccntml or main rib, 155

Mdhj juice, 49.

MimoscES, 413.

Mineral constituents of plants, 179.

Miniate: rami ion-color.

Mitriform : initrc-shaped, 503.

Molliiginero, 395.

IMonadclphia, 513.

Monadelphous : with filaments united
into a tube, or ting ; 280, fig. 4G2.

Monandria, 512.

Mondndions: with a single stamen, 279.

Mondnthous : oue-flowcivd.

Moni/ifoi in : necklace-shaped ; cylin-
drical and contracted at intervals.

Monimiacete, 3S2.

Monkey-bread, 399.

Mono-, in Greek compounds : one or
single.

Monorurpelhni : of one carpel.

Mon/ocai ptc, or monacal pian : once-fruit-
ing, 101

M^onocc'phulous : bearing a single head.

Monochlamydeous : with a single floral
envelope ; i. c. apctalous, 2G0.

]\fonorlinous : hermaphrodite.

Monaco/ i/le'donoiis : onc-cotylcdoned, 79,
326.

Monocotvledons or Monocotyledonous
Plants, 113,' 326, 370, 482.

Montecia, 513.

Monacioits : stamens and pistils in sep-
arate floweis on the same individ-
ual, 262.

Monogamia. 516.

Monogynia, 515.

Mon&pjnous: with onepistil orstyle, 287

Mono/cons: same as monoecious.

Monomerous: the parts of the flower
single, 234.

Mono] ic'talo its : one-petalled, but it is
used for pamopetalous, viz. petals I
more or less united into one hodv, j
249, 275.

Monophi/llous: one-leaved, of one piece, '
275.

Mbndpterous : one-winged.

Monopijiciioiis : one-stoned.

Monosrpalous : the calyx of one piece,
24 9.

Monospe'i motis: one-seeded.

Munostichous : in one vertical rank,
134.

Mondsti/lous : with one style.

Monotropea;, oi Monotropaccce, 440.

Monster, monstrous (430) : developed in
an nnnatuial manner.

Morphine, 57.

Morpholep/. 14, GO, 224

Mdi pilosis: the manner of development.

Moschate • exhaling the odor of musk.

Moulds. G5.

Mucilage: dissolved vegetable jelly, or
dextiinc, 55, 193

Mucdaipnous, mitcosp, or mucous: slimy.

Mucio: a short, sharp point.

Mucionitte: abruptly tipped with a m it-
em ; 1G2, fig 276, 231.

Mucionulute: tipped with a minute mu-
cio.

Mulberry, 475.

Mule: aJrybiid.

Miiltuiiipilar : many-angled.

Mnl.'i-, in Latin dei ivatives : many; as,

Multicipital (miillicpps) : many-headed;
where several buds or shoots pio-
ceed fiom the crown of one root.

Multifui ions : manv-sided.

Miiliijid: many-cleft, 159.

Mnliijloi ous : mam -flow ercd.

Multijur/ate : in many pairs.

Multilobular : many-celled.

i]f'dtiple: compound.

Multiple fruth, 309, 318.

Mu/lise'riiil : in several horizontal ranks.

Maltiseplate: many-partitioned.

Miincate- rough with shoit and hard
points.

Mnriculate: minutely muricatc.

Musaccyc, 490

Muscat dine, 503.

Muscari/bi m : brush-shaped.

Musci (Mosses), 502.

Muscifbim : moss-like.

Muscology: the department of Botany
which treats of Mosses.

Mustaid, 389.

Miiticous : pointless ; blunt.

Mycelium, 507.

Mi/colorjij, or M'l/crtd'oijij : the depart-
ment of Botany which treats of
Fungi.

Mycinpijle: see Mieropylc.

Myiicacece, 477.

MvrsinaccEB, 443.

MviisticacecD, 3S3.

Myrrh, 407.

MyrtacetB, 418.

GLOSSARY AND INDEX.

5-11

Naiaclaccm, 487.

Naked flowers : same ns nchlamydcous ,
or destitute of in\ olucre, &c.

Nnktd ornles and seeds, 296, 320.

Names of species and genera, 363 ; of
ordeis, tribes, &e., 373.

Ndplform : turnip-slui])Ctl, 84.

Nalant: floating' under water.

Kiitmal system, 365, 36G.

Nuturuhzed: species introduced, but
growing completely spontaneous,
and piopagating by seed.

Navicular : boat-shaped.

Nel> u lose : clouded.

Neck: the junction of root and stem.

Necklace-shaped: see Moniliform.

Nectar : the honey of a flower, or any
sweetish exudation.

Nectar// [nectar iutii) . a place or thing
in which nectar is secietcd : foi-
mcrly applied also to any anoma-
lous part or appendage of a flower,
whether known to secrete honey or
not, as to the spur-shaped petals of
Aquilegia, fig. G47, or the two
singular-shaped petals of Aeoni-
tum, 257, fig. 402, 404.

Needle-shaped: see Accrosc.

Nelumbiaceae (Nclumbo), 385.

Ne'mcous : filamentose; composed of
threads.

Nervation : the arrangement of the

Nerves: parallel and simple veins.

Neived: nervate; furnished with nerves,
154.

Nervose: abounding in nerves.

Netted: same as reticulated.

Neltr.d-vcined, 1 54.

Neiuose: same as nervose.

Neutral : without sexes.

Neutial flowers: having neither stamen
nor pistil, 263, 436.

Neutial quaternary pioduets, 196.

New Zealand Hemp, 492.

Nidulant: nestling in.

Nitid (uitidus) : smooth and shining

Niveous: snow-white.

Nodding : curved so that the apex
hangs down.

Node (knot) : the place on a stem
where a leaf is attached, 92.

Nodose : knotty ; swollen in some parts,
contracted at others.

Nodulose: diminutive of the last.

Normal: according to rule.

Notate: marked by spots or lines.

Noloihizal: the radicle bent round to
the back of one cotyledon ; same
as incumbent.

Nncumentaceous : nut like.

Nvcelle : same as nucleus.

Nuciform: nut-like.

4G

Nucleus: the kernel, 297, 320,322.

Nucleus of a cell, 26

Nucu/aiuuin : a name for a beny like a
grape.

Nucule : a diminutive nut, stone, or
kernel.

Niicitlose: containing nucules or nut-
lets.

Nunieious: same as indefinite.

Nut, 314.

Nutlet : a small nut, or the small stone
of a berry-like drupe.

Nutmeg, 383.

Nutaut : nodding.

Nutrition, 61, 177.

Nux-vomica, 434.

Nyetaginaecse, 4G3.

Nymplueaccaj, 385.

Oat, 498.

Ob- (over against) signifies inversely ,
as,

Obcompirsscd: flattened fore and aft, in-
stead of laterally.

Obcordale: hcin t -shaped inverted ; 162,
fig. 274, 233.

Oblcincfolate : lance-shaped, but broader
upwards.

Oblifjue, referring to shape, unequal-
sided, 165.

Obi delation, 309.

Oblong: elliptical, or approaching it,
and much longer than wide ; fig.
242.

Obovate: inversely ovate ; 157, fig. 232.

Obtuse: blunt; the apex an obtuse an-
gle; 162, fig 270, 236.

Obverse: same as ob.

O'bvolute: a modification of convolute,
145.

Oce'l/ate: eyed; a circular patch of
, color within another patch.

Oclnea (a boot): a tubular stipule;
, 171, fig 305.

Ocheate: furnished with ochreoe.

Ochiolimous: ocbrc-colorcd (pale dull
yellow) vciging to white

Octo-: eight ; in composition in such
wouls as the following.

Octaijyma, 515.

Oct (iifji nous : with eight pistils or styles.

Ocltininous: the parts in eights.

Octandria, 512.

Octdndious: with eight stamens.

Ocfojie'lalous : of eight petals/276.

O culate: eyed; same as ocellatc.

Officinal (belonging to the shop) : ap-
plied to plants. &c. used in medi-
cine or the ails.

Offset, 102.

Oilnut, 469.

Oils, 56, 57.

542

GLOSSARY AND INDEX.

Okra, 39S.

Oleaceffi, 459.

Oleraceous : of the nature of, or fit for,
pot-herbs.

Ol'nio-, in Greek derivatives : f?w ; as

Olifjandious: having few stamens.

Otiqospermous : few-seeded.

Oii've, Olive-oil, 4G0.

Onagraceoc, 419.

One-celled plants, 61.

One-sided: see Sccund and Unilateral.

Oophorida: the larger and compound
spores of Lycopodiaceas.

Opaque: the reverse of shining ; dull.

Ope'iculate: furnished with a lid or

Operculum: a lid. such as that of the
spore-ease of Mosses, 502.

Ophioglossece, 501.

Opium, 3S9.

Opposite (leaves. &c.) : opposed to alter-
nate, that is, placed over against
each other, 78,97, 133, 141. A
stamen, &c. is said to he opposite
a petal, when it stands before it
(248), as in fig 435 and G70.

Oppositifo'.ious : opposite a leaf, as the
tendrils of Viis, fig. 7G7, and the
peduncles of Phytolacca, fig. 10SG.

Orange, 401.

Orbicular : circular in outline.

Orehidaccae, 488.

Ordors, 359.

Ordinal: relating to orders.

Organic constituents, 179, 180.

Organization, 17.

Or/and p-ap/ig, 14, GO.

Organogeny : the development or for-
mation of organs, 2G3.

Organs, 18.

Organs of Reproduction, 70.

Oi'f/ans of Vegetation, 68, 70, 204.

Oiohanchacca;, 446.

Orris-root, 491.

Ortliopldceous (embryo) : with incum-
bent and conduplicate cotyledons,
as in Mustard.

Ortlwlropons, or oi thdtropal ovule ; 298,
' fig. 526. The term when applied
to the embryo is used as the con-
trary of antitropous, i c having
the radicle next the hilum, as in
an anatropous seed.

Osage Orange, 475.

Osmundaceaj, or Osmundinca?, 501.

Osseous : of the texture of bone.

Ouaii Poison, 434.

Oral: broadly elliptical ; 157, fig. 229.

O'carij : the ovule-hearing portion of a
, pistil, 223, 287.

Ovale : egg-shaped, or like the longitu-
dinal section of an egg, fig. 241.

Ocoid : a solid ovate or o\al.

Ovulate, ovuled, or ovullferous : bear-
, ing ovules.
Ovule: an unimpregnated seed or body

destined to become a seed, 223,

297.
Oxalidacca:, 404.

Palate : an inward projection of the
lower lip of a personate corolla;
278. fig. 459, 460.

Pdlea, or pah t : a chaff ; one of the
bracts on the receptacle of Coin-
positaj, 215, 435 ; one of the inner
bracts or glumes of Grasses, 497.

Paleaceous : chaff-like, or bearing chaff.

Puleola: diminutive of palea; one of
the minute innermost scales of the
flower of Grasses. See Squa-
mella.

Palmu; (Palms), 484.

Palmate : lohed or divided so that the
sinuses all point to the apex of the
petiole, either moderately, as in a
Maple-leaf, or so as to make tho
leaf compound, as in Horsechcst-
nut, when it is the same as Digitate ;
161, 1G3, 164.

Palmateli/ lohed, cleft, parted, &c , 1G1.

Palmateb) 2 - plurifoliolate, 164.

Palmate/// itemed, 156.

Palmdliful : palmately cleft ; fig. 265.

Palmdlisect : palmately divided ; fig.
267.

Paludose, palusti ine: inhabiting marshes.

Pandanaccaj, 485.

Pdnduiate, or pandiii ijbrm : same as
fiddle-shaped.

Panicle : a raceme, branched irregular-
ly ; 216, fig. 326.

Panicled, or paniculate: arranged in a
panicle.

Papaveraceaj, 388.

Pa paw. 383, 422.

Papayaceas, 422.

Papeuj : of the consistence of letter-
paper.

Papilionaccrc, 413.

Papilionaceous: butterfly-like, 253.

Papillose, or papillate: beating small,
soft projections (papillae, nipples
or pimples).

Pappose, or pappiferous : bearing a

Pappus (thistle-down), 260, 314, 435.

Papyraceous : papery.

Papvrus, 496

Paracorolla : an appendage or duplicate
of a corolla, such as was once
called a nectary.

Parallel-veined or nerved, 154.

Pardjihijsis : jointed thread-like bodies
accompanying the pistiilidia of
Mosses.

GLOSSARY AXD IXDF.X.

5-13

Parasitic plants, or Parasites : living on

the juices of other plants, 88.
Pauistemon : same as Staminodium.
Parenchyma: soft cellular tissue, 41.
Parietal : attached or belonging to the

walls, 292.
Parities : walls of an ovary, &c.
Pai ijtinnate : same as abruptly pinnate,

163.
Parnassiaceas, 394.
Parsnip, 426.
Patted, or partite : cut almost through ;

160, fig 262, 266.
Partial peduncle, 211.
Partial petiole, 164.
Puttied umbel, 216.
Parthenogenesis, 300, 340.
Passifloracese (Passion-flowers), 422.
Pate'lhfoim : kneepan-shaped.
Patent : spreading wide open.
Pdtulous : moderately spreading.
Pauci-, ill Latin derivatives : few ; as
Paiicifldrous : few-flowered.
Peach, 415.
Pear, 416.
Pear-shaped : ovoid at the extremity,

conical at the base.
Pe'ctinate : pinnatiful with close-set and

equal lobes, like the teeth of a comb

(pecten), 160.
Pcctine, and Pcctic acid, 55, 310.
Pedate : palmate, with the lateral lobes

again lobed ; appearing like a bird's

foot, 161, fig. 249.
PrduUli/: in a pedate mode.
Pedicel : the stalk of a particular flower,

211.
Pedicellate, pedicelled : having a pedi-
cel.
Peduncle: a. Mower-stalk in general

cither of one blossom or a whole

cluster, 211.
P<d&HCitlate, ped uncled : having a pe-
duncle.
Peloria, 278.
Peltate. : shield-form or target-shaped ;

fixed by the centre or some part

of the lower surface ; fig. 248, 681.
Pellinerved: pcltately veined.
Pdciform : open cup-shaped.
Pi ndent, pendulous : hanging down.
Penicii/ate, pcm'ciiliforni : tipped with a

brush of hairs, like a camcl's-hair

pencil.
Parnate : same as pinnate.
Pemuform : feather-like.
Pc'nninei ved : same as pinnately nerved

or veined.
Pcnta-, in Greek derivatives : five ; as
Pentacdrpeliarij : of five carpels.
Pmtacoccoiis: of five cocci.
Pcntagynh, 515.

Pcnturji/nous : with five pistils or styles,

287.
Pentdmcrous : of five parts; 234, 239,

fig. 354.
Pentandria, 512.

Pentdndious : having five stamens, 279.
Pentapetalous : of five petals, 276.
Pentaplajllous : five-leaved. 275.
Pentupteious : five-winded.
Pentasepalous : of five sepals, 274.
Penldstichous : in five vertical ranks,

135.
Pepo: a Gourd-fruit, 312. '
Pepper, 456, 469.

Perennial: lasting year after year, 84.
Perfect flower : one having both stamens

and pistils, 261.
Perfoliate: when the stem appears to

* pass through the leaf; 165, fig.
293. 294.

Pe'rfoiate : pierced with holes, or having

* transparent dots which look like
holes.

Pergame'ncous, or pergamentdecous : like
parchment.

Peri-, in Greek derivatives : around.

Perianth (peridnthium) ; the floral en-
velopes collectively, cither of one
set (calyx) or of two sets (calyx
and coiolla), 222.

Pe'ncaip : the ovary in fruit, 308.

Pericdipic: belonging to the pericarp.

Pericha'tial : relating to tho

Pe'iic/mth, or pericluetium : the cluster
of peculiar leaves surrounding tho
base of the fruit-stalk of Mosses

Periclinium : a name for the involucre
of Composite.

Periderm : same as Epiphloeum.

Pe'rigone, or periydnium : same as Peri-
anth.

Perigijiiinm : bristles or other organs, of
doubtful nature, around the pistil in
Cypcraccai, 497.

Perigipious : borne on the calyx ; liter-
ally around tho ovary ; i. c. when
the petals or stamens aie adnatc to
the base of the ovary or to the
calyx ; 251, 268. fig. 388, 389, 281.

Peripc talons : aiound the petals.

Peiipheuc: surrounding the ciicumfer-
encc. 325 ; as the embryo aiound
the albumen in fig. 62 1

Pe'risperm: the albumen of the seed,
322, or that albumen which is
formed in the tissue of the nucleus,
323.

Pe'n'stome, 502.

Peritiopous, perihopal (seed) : horizon-
tal to the axis of the fruit.

Perpendicular si/stem of the stem, 112.

Persimmon, 443.

544

GLOSSARY AND INDEX.

Persistent: remaining, as the leaves of]
evcigrcens tin ough the winter, 172 ;

and the calyx, &c. of many plants

until the fruit is formed, 279.
Pe'rsomite : masked ; 278, fig. 459,

4G0.
Perfuse: having slits or holes.
Peru/ate: having p€iulai or bad-scales.
Peruvian Baik, 432.
Petal: a leaf of the corolla, 222.
Pelulme, or pe'tulotd: petal-like, in color

and texture, 260
Pe'/iolar : borne on the petiole.
J'e't.olate, petio/ed: having a petiole.
Petiole: leafstalk, 145, 170.
Pctidlulatc: the leaflet stalked, 1G4.
Peliolule: the stalk of a leaflet, 104.
Pliandi/amous, or phanerdrjamous ; hav-
ing manifest flowers, 69.
Phamogamous or Phanerogamous

Plants, 69, 369, 375.
Phalanr/es: bundles of adelphous or

clustered stamens.
Phordntluum : the lcccptacle of Com-

positac.
Plirymaccae, 450.
Phycdlogi/ : same as Algology.
Pliylla: leaves, 274. -Jiliijliuus : leaved,

as 3-phylloiis, three-leaved, &c.
Plu/Hodineous: beating or lcsembling a
Phyll odium : a dilated petiole taking

the place of a blade, 1^0
Phi/Hot axis, or phyllotdrif, 133.
Physiological Botany, 14, 17.
Phytclephanteae, 485.
Phyldgraphy: dcseiiptive Botany.
Phytolaceaceas, 463.
Ph/tdloyy : Botany in general
Phyton : a simple plant-individual, or

plant-clement 9G.
Phi/tdtomy: vegetable anatomy, 14.
Plicate, pile/form: like a cap or
Pileus, 507.
Pdcoihiza: the cap of a root, as found

in some aquatic plants; fig. 102.
PUiftrons: bearing or lipped with hairs

ipiit).

Pdosc: hairy, as distinguished from
woolly or downy ; i c distinct and
straight, but not ligid hairs.

Pilosili/ : hairiness.

Pimento, 418

Pine-apple, 492.

Piney Tallow, 400.

Pink-root, 435.

Pinna: one of the piimary divisions of
a pinnatcly compound leaf, 1 64.

Pinnule, pinnated: a compound leaf
with leaflets arranged along the
sides of a common petiole; 163,
fig 288-290.

PtnnaUly cbj'l, lobed, parted, &,c, 160.

Pinnatehj Z-pha-ifoliohte, &e , 1G4.

Pinnate/// veined. 155, 1C0

Pmndtijid: pinnatcly cleft J fig. 261.

Pmndtisict: pinnatelv divided; fig.
k63.

Pinnule: a secondary division of a pin-
nately compound leaf.

Piperaceae, 4G9.

Pipeline, 469.

Pisiform : pea-shaped.

Pistachio-nut, 406.

Pistil: the ovule-bearing organ of a
flower, 223, 287.

Pistillate : furnished with pistils, or phs-
tils onlv, 261.

Pistdlidnnn', 337.

Pitch, 4S0.

Pitchers: sec Ascidium ; 1G9, 387, fig.
299-301.

Pitcher -shaped: campanulatc or tubular,
but with a narrower mouth.

Pith, 118.

Pits, 37.

Pitted: marked with small depressions.

Pitted tissue, 45.

Placenta : the place or part of the ovary
which bears the o\ulcs or seeds,
289.

Placentation : the arrangement of pla-
centas.

Pluceiitifeiom: bearing the placentae.

Pluccntiform : nearly the same as quoit-
shaped.

Plaittd: see Plicate, 273.

Plane: flat.

Plantaginaccic, 444.

Platanaccffi, 476.

Platijcdrpous : broad-fruited.

Pleio-, in Greek deiivatives : full of, or
many ; as

Pleiospeimous : many-seeded, &c.

Pleure'nchyma : woody tissue, 41.

Plcworliizul : embryo with the radicle
lying against the side or edge of
the cotyledons ; same as aeeum-
bent

Plicate, plicalivc : thrown into longitu-
dinal plaits (plicae) ; folded, 144,
273.

Plum, 415.

Plumbaginaceae, 444.

Plumose : feathered ; when bristles, &c.
have fine hairs on each side like
the plume of a feather, as the pap-
pus of Thistles, &c. ; fig. 890.

Plumule: the bud or growing point of
the cmbiyo above the cotyledons,
71, 324

Pluii-, in words of Latin origin: sev-
eral, at least moie than one; as

Phtiifldioiifi : several-flowered.

Plui ifdliolate : bearing several leaflets.

GLOSSARY AXD INDEX.

545

Phtrildculeir : several- celled.

Ponihfoi in : deep cup-shaped.

Pod: a dry dehiscent fiuit, 315.

Pddosperm": seed-stalk, 297.

Podostcmacese, 471.

Pointless: see Muticous.

Pointletted: same as Apiculatc.

PolcmoniacciB, 453.

Pollen : the contents of the anther, 223,
235.

Pollen-tube, 28G, 302.

Pollinia : pollen-masses, 286, 489.

Pollimfei ous : hearing pollen.

Poly-, in Greek compounds : numerous.

Polyadelphia, 513.

Polyadelphous : having the filaments in
' several sets, 2SU.

Polyandria. 512

Pofydndrous : with numerous stamens,
especially when inserted on the
receptacle, 242, 280.

Po'yduthous : many-flowered.

Puiycdi pic : fruiting many times, i. e.
year after year ; perennial. 101.

Polyce'phalous : "hearing many heads.

Polydadous : much-branched.

Polycdccous: of several cocci.

Po!ycotyle'do:io,is : having several cotyle-
dons, 79, 326.

Polygalacea:, 411.

Polygamia, 513, 515.

Po.'yjamous : having both perfect and
separated flowers, 262.

PolygonacCiB, 465.

Pofyjonons : many-angled.

Polvgy'na, 5 15.

Puhjyyno.is : with numerous pistils or
styles, 287.

Polymerous: formed of many members.

Polymdi p/ious ; vaiious in form.

Po'ype'kdons : having distinct petals,
249, 275.

Pdlypliore : a common receptacle of
many carpels, as in Strawbeiry.

Polyphylfous : many-leaved or several-
leaved, 275.

Polypodiaccse, or Polypodincaj, 501.

Polyrlnzal : many-rooted.

Po'ysepulon.s : of "two or more distinct
sepals, 249, 275.

Po'yspermous : many-seeded.

Poiyspoious: containing many spores.

Polysle'moiious : with many stamens.

Pome: an apple, pear, &c, 312.

Pome*, or Pomaccsc, 416.

Pomegranate, 418.

Poimfeious : pome-bearing.

Pum'olojy : the department of Botany
relating to fiuits.

Pontcdei iaccse, 495.

Poiose: poious. having holes.

Poriulacaccaj, 396

4G*

Posterior (in the flower) . next the com-
mon axis, 237.
Pdsticous: same as cxtrorse.
Potato, 456, 455.
Pouch: see Silicic, 317.
Prtef oration: same as ^Estivation, 269.
Prafohalion : same as Vernation, 143.
Prw.mdise: as if bitten ofl'.
Prickli) : armed with
Prickles, 52

Pi (mine : outer coat of the ovule, 298.
Primdidial leaves, 143 ; utricle, 26.
Primulaccaj, 443.

Prismatic, prismalical : with flat longi-
tudinal faces, separated by angles.
Process: any projection fiom a surface.
Piocumbent : lying along the ground,

102.
Produced : prolonged or extended.
Pro-embryo, 338.

Proliferous (hearing offspring) : develop-
ing new branches, flowers, &c. fiom
the older ones, or f.om unusual
places.
Prone : lying face downwards.
Proper juices, 57.
Prose'nchyma, 4 1 .
Pioscnlhesis, 236.

Piostrate : lying flat on the ground, 102.
Proteaccce, 468.
Proteine, 27, 53, 57, 196.
Pioterdnthous: where flowers arc pro-
duced earlier than the leaves.
Prothdllus, or protothallus, 338.
Protophytcs : Alyffi and Lichcnes are

so called.
Pidfoplasm, 26, 53, 57, 196.
piiiinate, pruinose: as if frosted over.
Prdwfoi m : plum-shaped.
Pseudo-bulb : a kind of conn, as of epi-
phytic Orehidacea!.
Pseudo-pa i asitic: same as epiphytic.
Pterocdi pons : wing-fruited.
Pteioid: wing-like.
Pubescent : clothed with soft or downy

hairs, or pubescence.
Piujidnijbi m : dagger-shaped.
Pulque, 491.
| Pulse. 413.
j Pulveraceous, or pulre'riilent : dusty or

powdery on the surface.
| Pulruiate : cushioned
I Pulcinns (a cushion) : an enlargement
at or below the base of a leafstalk.
I Pumpkin, 423.

Punctate : dotted as if by punctures.
I Pungent : pricking ; rigid-pointed.

Pustulate: blistered.
I Putdmen: the stone or shell of a drupe,

310, 312.
I Pyrenw : the stones of small drupes ;
j same as nucules.

54G

GLOSSARY AND IXDKX.

Piriform : pear-shaped.
Pyroletc, or Pyrolaccm, 440.
Pytidate; furnished with a lid, like a
Pijxidium, or pi/xis: a pod openina by a
lid; 317,' fig. 575, 588, 950,'&c.

Quadrdnanhr : four-angled.

Quadri-, in Latin compounds : four.

Qiiadrifin ions : in four vertical ranks.

Quadri fid : four-cleft.

Quadri [foliate : four-leaved.

Qiiadrifoholate : of four leaflets.

Qiadrijut/ate : four-paired.

Quadripartite : four-parted.

Quandang-nuts, 460.

Quassia, 405.

Qiate'i nary : consisting; of four, 239.

Quaternary products, 53, 57, 19G.

Qiate'nrite: in fours.

Quercitron, Qucrcinc, 476.

Qutii-, in Latin compounds : five in

number
Quinaii/: consisting of five, 234, 239.
Q'dnate : in fives.
Quince, 416.
Quincuncial : five-ranked ; in a quincunx,

135, 270
Quinine. Quinia, 57, 431.
Quniqucfai ious : five-ranked.
Qiiinquvfbliatp. : fi vc-lcavcd.
Qiinquefdliolate: of five leaflets.
Qianqueldcnlar : five-celled.
Quinquina Bark, 433.
Quintuple : dividing into five parts.
Qiiintiiplp-i ibbed, or
Quinlupli-nerocd, 156.

Race: a varietv pcrpetuablc by seed.
356.

Raceme: an indefinite inflorescence with
single pedicelled flowers arranged
along a prolonged axis; 211, fig.
307.

Racemiferous : bearing racemes.

Racemiform: resembling a raceme

Racemose: bcaiing or resembling ra-
cemes.

Rachis : see Rhachis. ,

Radial: belonging to the border or ray

Radiate, radiant : spreading from or
arranged around a centre ; having
rays

Rddiated-veined, 156.

Radical: relating to the root (radix).

Radical leaves : those apparently spring-
ing from the root, 143.

Rddiranl: looting.

Radicel: a diminutive root or rootlet.

Radici/loious: flowering from the root,
or apparently so.

Radiaform: appearing like a root.

Radicle : a dinrinuth e root ; tiro part of

an embryo below the cotyledons,
71, 324.
Radii : rays.
Ruffleskieccc, 461.
Ramal, or ramcul : relating to branches,

143.
Rame'nta, raments: thin chaffy scales in

place of hairs.
Rameiitdceous : bearing raments, as the

stalks of many Ferns.
Ramification, 97.

Rdm'/lorotis : flowering on the branches.
Ramose: bearing branches (iami) ;

branchy.
Rdmitlosc: bearing many branchlcts

(idmuli).
RanimculacesB, 380.
Raphe: sec Rhaphc.
[{aphides : crystals in plants, 59
Rare: thinly set; sparse or few.
Raspberry, 416.
Ray: the marginal flowers of a head,

when different from the rest, 436 ;

the branches of an umbel, &c.
Ray-flower, 436.

Receptacle of the flower, 224, 266.
Receptacle of inflorescence, 211, 215.
Recess: same as sinus.
Re'clnuite, icchned: falling or turned

downwauls.
Re'clinei red : parallel-veined.
Rectise'riul : in rectilinear lanks, 141.
Recuived: curved, especially curved

backwards.
Reduplicate, ? eduphcative, 273
Reflc'xed : bent downwards or back-
wards.
Refi acted: suddenly bent backwards.
Riyulai : the members alike in size and

form, 239, 277.
Rz'iiijbtm: kidney -shaped ; same as

round-heart-shaped, but the breadth

greater than the length ; fig. 2-15
Repdnd: bowed, the margin obscurely

sinuate, 159, fig. 257"
Repent: same as creepinfr, 102.
Replicate: folded back.
Re'plum (a door-case) ; the frnme-liko

placentas of Papaveraceaj, &c from

which the valves of the pod fall

away in dehiscence.
Reproduction, 20 21. 61 ; — in Cryptoga-

mous plants, 330.
Reproductive oigans, 70.
R<)i!ant : same as repent.
Rcscdaccaj, 391.
Resins, 195.

Respiration, 178, 199, 202.
Restiaccre, 496.
Resupinale : underside up, or having that

appearance.
Reticulated: netted, 154.

GLOSSARY AND INDEX.

547

Rclicuhiren ducts, 46.

Retinaculum: a stay or holdfast: rip-
plied to the piocesses bcuiing the
seeds of Acanthaccoe, &c.

Re'tinetved : same as reticulated.

Rett ociirred : same as recurved.

Retro flexed : same as retiexed.

Rett ofracted : same as refracted.

Rettdrse: backwards, directed back-
wards.

Retrove'i ltd : turned upside clown.

Refuse : slightly notched at a rounded
apex; 16'2, fig. 272.

Re'colute, resolutive: rolled backwards,
144.

Rhachis (back-bone) : the axis of a
spike, &c., 211.

Rhamnaccae, 408.

Rhaphe of an ovule or seed, 299, fig.
529, r.

Rhatanv, 412.

Rhizdiithuus : root-flowcrcd ; as when a
flower (like Rafflesia, fig 150), or
a cluster of fioweis, &c without
green foliage (like Beech-diops),
is parasitic by what answers to
roots, on some foster plant.

Rhizocdi pons (root-fruiting) : having a
perennial root.

Rhizdma: rootstock, 106.

Rhzomorphous : root-like.

Rhizophoraceaj, 419.

Rhodospennete, 509.

Rhombic : rhomb-shaped.

Rhomboidal : appioaching a rhomboid
in form.

Rhubarb, 466.

Rib : a strong nerve or part of the frame-
work of a leaf, &c , 145, 155.

Ribbed: when stiong nerves or ribs run
lengthwise through a leaf, &c.

Ricciacese, 504.

Rice, 498.

Runose : with chinks or clefts (riina).

Ring of Ferns, 501 ; of Mosses, 503.

Ringent : grinning ; when a bilabiate
corolla is open, 278.

Riparious: along water-courses.

Root, 79.

Root-hairs, 81.

[lootlet : a very small root, or ultimate
branch of a root.

(loot slock: same as rhizoma, 106.

Rosaccre, 415.

Tiosnceous : rose-like, 276.

Rdstcllate: diminutive of rostrate.

Rostellinn : a little beak.

Rdstiate: beaked, bearins a

Rostium : a beak-like projection.

Rdsulnr, or rosulute : shaped like a ro-
sette.

Rotate: wheel-shaped; 278, fig 454.

Rotation in rclls : sec Cyelosis, 31.

Rotund, tottindale: of lounded outline.

Rough: see Scabiid or Scabious.

Rubcscent, i uhiiund : reddish or losy.

Uubiacese, 431.

Rubigitiose : msty reddish.

Riideial: growing in mbbisli.

Rudimentai 1/ : i in perfectly or incom-
pletely developed.

Ruf scent : approaching to

Rufous: brown-red.

Rugose: wrinkled (ruga, a wrinkle).

Ruminated (albumen) : penetrated with
holes or channels; 323, 383, fig.
G58.

Riincinate: saw-toothed, the teeth turned
backwards, 161, fig 279.

Runner, 102.

Running, 102.

Rupcstrine : glowing naturally on rocks.

Ruptile: bursting: irregularly.

Rusty: sec Fcnugineous.

Rutaeeaa, 405.

Rye, 498.

Sdbuline, or sdbnlose: growing in sand.

Saccate, sacciform : sac-shaped, 278.

Sac of the amnios, 304.

Raffion, 491, 437.

Sagittate : anow-hended, or arrow-
shaped ; lanceolate with a lobe at
the base on each side pointing
backwards ; fig. 252.

Sago, 481, 485.

Salep, 489

Salicaccre, or Salicinia?, 478.

Salicinc, 478

Saline, salsuginous : growing in salt
places, or impregnated with salt.

Salver-shaped : tubular and the holder
spreading flat at light angles to the
tube ; 277, fig. 457.

Salviniesc, 502.

Samara: a kev or winged indchiscent
fruit, 314, fig. 577, 578.

Sdmaroid: resembling a samara.

Sambucca3, 431.

Sandal-wood, 414, 469.

Snntalacca;, 468.

Sap, 53 1 90.

Sapindaccre, 409.

Sap-green, 408.

Sapodilla Plum, 443.

Sapotaccai, 443

Sap-wood, 35, 124, 126

Sdrcocarp : the fleshv part of a drupe,
310, 312.

Sarmentdceous : bearing or resembling

Sarments : l tinners or long and flexible
branches.

Sarraccniacca;, 387.

Sarsapatilla, 493.

548

GLOSSARY AND INDEX.

Saururaecaj, 4G9.

Saw-toothed : same as Serrate.

Suxatile : living in locky places.

Saxifiagaccae, 424.

Scab) ate, scubrid, or scabrous : rough to

the touch.
Scaldriform : ladder-shaped, or barred.
Scalarifcrm dads, 4 6.
Scales : any thin scale-like appendages ;

usually degenerated leaves, 105.
Seal I o peel : same as Cicnatc.
Seal n : furnished with scales, 95, 191.
Scammony, 455.
Scandent : climbing.
Scape : a flower-stalk rising from the

ground or near it, 220.
Scdpiform, or scupoid : resembling a

scape.
Saw: sec Leaf-scar and Hilum.
Scdiiose, or scdrious: thin, dry, and

membranaceous.
Scatteied : cither sparse, or without ap-
parent symmetry of arrangement.
Schizandrese, 382
Scion: a shoot, especially one used for

grafting.
Sciuroid: like a squirrel's tail.
Sclcranthcas, 396.
Scle'rogen : same as Ligninc, 36.
Scobiform, or srohicidui : like sawdust.
Scdrpioid : coiled loimd like a scorpion,
as the branches of the cyme of
Heliotrope.
Scroliculate : pitted.
Scrophulariaccoj, 448.
ScrdUfoim : pouch-shaped.
Sctaf: minute or bran-like scales on

the epidermis, 52.
Scutate, scutiform : shield-shaped.
Scute'i/iforin : shaped like a platter (scu-
te/la).
Secretions, 51.

Stride : divided into portions.
Sec it ml : all turned to one side of an

axis.
Secundine : the second coat of an ovule,

298
S'ed, 70, 320.
Smi-wssd, 308.

Segment: one of the divisions or lobes
of a leaf or other organ ; 159, 275.
Se'iregate : kept separate
Semi-, in Latin compounds : half.
Semi-adherent: the lower half adherent.
Semi-amjilexicaul : half-clasping.
Semirordate : half heart-shaped (divided

lengthwise).
Semi-double : half-double.
Semi-floscular : when the flowers of a

head are ligulate.
Semilunar, or semilunate : like a crescent
or half-moon.

Seminal : relating or belonging to the

seed.
Seminifeious : seed-bearing.
Ssnuoi bicular : half-iound.
Semioval : half of ah oval, and
Semioeate: half of an ovate figure, di-
vided longitudinally.
Semtsaijittale : arrow-headed with one

lobe wanting
Semiseptnte : a partition reaching partly

acioss.
Semiterete : half-cylindrical.
Sempercirent : evergreen.
Senna, 414.
Sensitive plants, 345.
S^pal : a calyx-leaf, 222.
Scpa/me, sepalous : relating to sepals.
Sepaloid : resembling a sepal.
Separated floivos: the stamens and the
pistils occupying separate blossoms,
261.
Septate: with a partition (septum).
Septicidal, or septic de : dehiscent
through the partitions, i. c. by the
lines of junction ; 316, fig."582;
584.
Septifeious: bearing a partition.
Septifi ugid : where the valves separate

fioin the dissepiments, 317.
Septum (plural septa) : a partition of

any kind, 316.
Serial, or se'iiate: arranged in rows.
Seiiceoits: silky.
Senes: rank.

SmOtinous : flowering or fruiting late.
Seirute: beset with teeth pointing- for-
wauls, like those of a saw, 159, fi"-.
254.
Se'natines: the teeth of a serrate body.
Serrulate : serrate with fine teeth.
Sesamcre, 447.
Se'sst/e. (sitting) : not stalked, 145, 211,

281.
Setei : a bristle, or bristle-like body, 52.
Setaceous, sehform : like a bristle. *
S ttgeroiis : bristle-bearing-.
Setose: bearing or abounding with bris-
tles.
Se'tnla : diminutive of Seta
Se'tulose: bcaiing minute bristles.
Sex: six ; as in
S'rangular : six-angled.
Serfarious : six-rowed.
S"xpartite : six-parted, &c.
Sliaggi/ : sec Villon*.
Sheath : a tubular bod}-, enclosing or
surrounding- some" other; as the
base of the leaves of Grasses ; 1 70,
fig. 237.
Sheathinq : forming a sheath ; sec Va-
cillate.
Shields : sec Apothecia, 506.

GLOSSARY AND IXD::X.

549

Shield-shaped: sec Tel tatc, 158, fig 248,
681.

Shoot : any fresh branch.

Shrul>, shiithby, 101.

Sigdlate : as if marked with the impres-
sion of a seal, as in Solomon's Seal,
fig. 168.

Sir/moid : curved like the Greek sigma,
or letter S

Signs used in Botany, 517.

Silencsa, 395.

Si/icle: a pouch, or short pod of Cru-
cifcrao. 317, fig. 703.

Siliculosa, 515.

Sdiculose: having or resembling a sili-
cic.

Sdique: a long pod of Crucifersc ; 317,
fig. 589.

Siliquosa, 516.

Siliquose: like a siliquc.

Silk-cotton, 399.

Silky : clothed -with fine, apprcsscd, and
glossy hairs, producing a satiny
surface.

Silver-berry, 468.

Sdrer-grain, 120.

Simarubacerc, 405.

Simple: of one piece or rank.

Simple ft litis, 309, 311; leaves, 162;
pistil, 288.

Sinisti drse : turned to the left.

Sinuate: stiongly wavy on the margin,
with alternate convexities and con-
cavities ; 159, fig. 258

S'nvs : a re-entering angle or recess.

Slashed : same as Laciniate.

Sleep of plants, 344.

Smilaceaj, 492.

Smooth : not pubescent or hairy, or else
(and more strictly) not rough.

Snake-root, 412,462.

Soap-hen y, 410.

SoboHferom: bearing shoots (sobriles).

Social (plants) : growing gregariously.

Solanacca:, 4 56.

Solitary : single ; alone.

Soluble: scpatating into parts.

Soie'diate • bearing little patches on the
suiface.

Soiose : heaped, or bearing.

Sordsis : a fleshy multiple fruit, like a
mulberry.

Sori (sing, sorus) : heaps or patches, as
those of the spore-cases of most
Ferns, called in English fruit-dots,
501.

Spadiccous : bearing a

Spadix : a sort of fleshy spike, 213.

Span : the length spanned between the
thumb and little finger ; seven or
eight inches.

Sparse : scattered and generally scanty.

Spatluiceous : bcai ing a

Spat he : the enveloping bract of a spa-
dix, 213.

Spdthulate, or tpatulate: shaped like a
druggist's spatula.

Special directions, 341.

Species, 19, 354.

Sperifc : relating to species.

Spe'rmaphore: a name for the placenta,
or the funiculus of the seed.

Spermatozoids, 334.

Speitnic, or spermous : relating to the
seed.

Spe'rmoderm : the outer seed-coat, 320.

Spicute: relating to or disposed in a
spike.

Sptriform : spike-like.

Spicvla: a spikclct.

Spike: a prolonged indefinite infic-
resccncc with sessile flowers, 212.

Spikelet: a diminutive or secondary
spike ; the ultimate flower-clusters
of Grasses.

Spikenard, 435.

Spindle-shaped, 84, fig. 138.

Spine, 104, 167.

Spmescetit : tipped with a spine, 104.

Spinose: spiny, 104.

Spinulose: bearing diminutive spines.

Sp nil: as if wound round an axis.

Sphal arrangement of leaves, 134.

Spiral markings on cells, 39.

Spiral i>essels or ducts, 46.

Spircas, 416.

Spithainasous : a span high.

SpoiHjioles, or spongelets, 80.

Spongy : of the texture of sponge.

Spontaneous movements, 340, 347.

Sporadic: widely dispersed.

Sporangium : a spore-case, 337, 500 &c.

Spore:' the body in Oryptogamous
plants which answers to the seed iu
the Phrcnogamous, 6!, 70, 331.

Spore-case, 337.

Sporiferous : sporc-bcaring.

Spdrocaip: a kind of spoiangium, 502.

Spoils, 356.

Spdru/e: a spore, or small spore.

Spornlifnous : hearing sporules.

Spumescent, spumose : froth-like.

Spur: any tubular projection, 278.

Spurred: "bearing a spur, 278.

Squamate, snuamoie, sipiamiferous : fur-
nished with scales (squama?).

Squdmcllate : with or resembling- minute
and narrow scales (squamclhe, 497).

Squdmiform : scale-shaped.

Squcimulifnrm : like a small scale, or

Squdmula, 497.

Sqiidmulose : covered with small scales.

Squarrose: where scales, small leaves,
or other bodies, spread widely from

550

GLOSSARY AND INDEX.

the nxis on which they arc
crowded.

Sjndriulose: diminutive of Squarrosc.

Squash, 423.

Squills, 493.

Stalked: furnished with a stalk, stem,
or any lengthened support.

Stalked (/lands, 52.

Stalklet : a diminutive or secondary
stalk.

Stamen : the fertilizing organ of a flow-
er, 223.

Stdminate, or stamineal: relating to the
stamens. A staminale flower has
no pistils, 261.

Stannnifeious : hearing stamens.

Staminddium: an altered and sterile sta-
men, or a body occupying the place
of a stamen.

Standard: the posterior petal of a pa-
pilionaceous corolla, 253.

Staphylcaccce, 409.

Star-apple, 443.

Starch, 54, 193.

Staticea;, 445.

Station: the locality or kind of situa-
tion in which" a plant naturally
grows.

Stellatse, 432.

Stellate: starry, star-shaped; arranged
in lays, like the points of a star.

Stellate hairs, 52.

Stc'1/u/ate : diminutive of Stellate.

Stem, 91.

Stem/ess: having no obvious stem, 91.

Slemlet: a diminutive stem; the first
intemode of the plumule.

Sterculiaceaj, 399.

Sterigma: the adherent base or down-
ward prolongation of a decurrent
leaf.

Sterde: barren.

Sterile flower : one having no pistils,
261.

Sterile stamens or filaments: those des-
titute of anthers, or with the anther
imperfect, 281.

Stigma : the part of a pistil which re-
ceives the pollen, 223, 287.

Sligmdtic, or stigmatose : relating to or
bearing the stigma.

Stings, stinging haiis, 52.

Stipe (stipes) : a stalk of an ovary (267),
of a Mushroom (507), and the
leaf-stalk of a Fern.

Stipel: the stipule of a leaflet ; 171, fig.
286.

Stipellate: furnished with stipels, 171.

Stipitate: having a stipe, 267.

S'ijiitiform : shaped like a stipe.

Stipuldceous, stipular : belonging to or
resembling stipules.

Stipulate, stipulcd: possessing stipules,

171.
Stipule: an accessory part of a leaf,

one on each side of the base, 145,

170.
Stock, 355.

Stole, stolon: a rooting branch, 102.
S'oloniferous : bearing stolons.
Stoma (plural stdmalu), stomate : a

breathing-pore, 52, 1 50.
Stomatiferous : bearing stomates.
Stone : the endocarp of a drupe.
Slone-fnut, 312.
Stool : the plant from which layers arc

propagated.
Storax, 425, 442.
Stramineous : straw-like.
Strangulated : irregularly contracted.
Strap-shaped: see Ligulatc.
Stratum : a layer.
Strawberry, 416.
Striate : marked with longitudinal

streaks or furrows (stria).
Strict : very straight or close, or very

upright.
Strigtl/ose : same as Strigosc.
Stiigose: clothed with sharp and stout

close-pressed hairs or scale-like

bristles (strigo?).
Stroht/dcioiis : l elating to, or resem-
bling a
Shdhile : the cone of a Pine, &.C., 319.
Stiobdiferous: bearing strobiles.
Sliomlmliferons : spirally twisted, like a

corkscrew or a stiombus
Stwphiole: same as a Caruncle, 322.
Structuial Botany, 14.
Strumose: swollen on one side, beating

nstiuma or wen.
Strychnine, 57, 434.
St a pose: tow-like.
Sti/le : a columnar or slender part of the

pistil above the ovary, 223, 287.
Sfyliferous : style-bcai ing.
Stijliform : style-shaped.
Stylopodium : an enlargement or fleshy

disk at the base of a style, as in

Umbelliferae.
Styracca?, 442
Sub-, as a prefix, means somewhat, or

slightly ; as
Subacute : somewhat acute.
Subclass, 362.

Suhcordate ; slightly heart-shaped, &c.
Siiberose: of a corky texture.
Subgenus, 361, 362".
Submerged : growing under water.
Suborder, 361.

Subspecies : a marked variety.
Subtrihc. 361.

Subtei ranean : growing beneath the sur-
face of the ground.

GLOSSARY AND INDEX.

5.51

Subulate, snbuliforni ; awl-shaped ; nar-
row, and tapering to a sharp rigid
point, as the leaves of Juniper, &c.
166.

Sicctse: as if cut off at the end.

S'txase, succulent: juicy.

Succulious: the apex of caeli leaf cov-
ered by the base of the next, as in
Jungcrmahnia.

Succulent leaves, 1C6.

Sucker, 102.

S iff) utc'ticent : slightly shrubby, 101.

S'ljfuitex: an undcrshrub

Sujj'i littcosc : low and shrubby, or shrub-
by at the base, 101.

Sugar, 53, 193, 194

Sulcale: longitudinally grooved.

Super-, above ; as

Super-axillary : above the axil.

Superior: above, 252 ; also, on the up-
per side of the flower, i. e. next the
common axis (237), as, for exam-
ple, the vcxillum of a papiliona-
ceous coiolla (fig. 372, a) is the
superior petal.

Stper posed : one above another.

Superposition, 248.

Snpervoliite., 274.

Supine: lying flat with face upwards.

Suppiession: obliteration of parts, 239,
255.

Sipru-, above ; as

Supra-axillary : above the axil.

Supra-decompound : several times com-
pounded.

Siirculose: producing suckers.

Siii cuius: a sucker, 102.

Suspended: hanging fiom the apex, 297.

Sispensor of the embryo, 300.

Sutinal: relating to the

Suture: the scam, or line of opening
of a pod, &c., 289.

Sicoi d-shaped : a blade with two sharp
and nearly parallel edges, tapering
to a point, as in Iris, fig. 291.

Syconium, or syconus: such a fruit as a
fig.

Syinmi-trical : equal in the number of
all the parts, 232, 239.

Sjmpetcdo'is : becoming somewhat mon-
opctalous by a junction of the base
of the petals with the monadcl-
phous stamens, as in the Mallow
family.

Simphijdntherons: same as Syngcnesious.

Symphysis: a growing together of parts.

Si/mplii/ste'inonoiis : the stamens united.

Svmplocincae, 4 43.

Sjnuiitlieious: united by their anthers;
wheirce Composite have been
named

.Svnanthcra, 435.

Syncdrpcms : formed of two or more

united carpels, 290.
Syncoty/c'donous : the cotyledons soldered

together.
Synedial: growing on the angles.
Syne'mu : a name for a column of mon-

adelphous filaments.
Syngenesia, 513.
Syngenes:otis: stamens united by their

anthers; 280, fig. 403.
Synonijme: equivalent or superseded

names.
Synonymy : what relates to synonymes.
System, 305, 300.
Systematic Botany, 15, 351.

Tahescent : wasting or shrivelling.

Tabular: flattened horizontally.

Tad : any long and slender terminal
appendage.

Tail-pointed : tipped with a prolonged
and weak acuminatum..

Tannin, Tannic Acid, 57.

Taper-pointed: same as Acuminate.

Tapioca, 472.

Tap-root, 84.

Tar, 480.

Taro, 485.

lawny: dull yellowish, verging to
brown.

Taxinca:, 480.

Taxd/oyy, or Taxdnonnj : the depart-
ment of Botany which relates to
classification.

Tea, 401.

Teasels, 435.

Teeth of calyx, corolla, &c , 275 ; of
leaves. 159.

Teqmen : the inner seed-coat, 321.

Tendid, 102, 167.

Tepal : a name proposed for a leaf or
part of the perianth when it is un-
certain whether it belongs to the
calyx or the corolla.

Teratoloqi/ : morphology applied to
monstrous states.

Tercine: a third coat of the ovule.

Terete : long and round, i. e. the cross-
section circular.

Tergemmate : thrice twin.

Te'rminal : belonging or relating to the
summit.

Terminoloyij : the same as Glossology,
15.

Ternary: consisting of three, 239.

Ternary products, 53.

Termite: in threes.

Tcrnstroemiacese, 401.

Tessellated: in checker-work.

Testa: the outer seed-coat, 320.

Testaceous: brownish-yellow, like un-
glazcd earthen-ware.

552

GLOSS AKY AND IXDI.X.

Tetra-, in Greek compound words : four.
Tetracdrpdlury : of four carpels.
Teiracdmaroits : same as
TetiaaSccous: of four cocci.
Tetradynamia, 512.
Tetradynamous : two of the six stamens
shorter than the rest: 281, fi<>.
407.
Tetrdijonal, or tctrdgonous ; four-angled.
Tctragynia, 515.
Tcli dyynous : with four pistils or styles,

287.
Tetrdmerous : the parts in fours, 234.

239.
Tetrandria, 512.

Tetrdndious: with four stamens, 279.
Tetiapclalous: with four petals, 276.
Tetraplnjllous : four-leaved, 275.
Tetraquetious: quadrangular, with very

sharp and salient angles.
Tetrasepalous : with four sepals, 274.
T/rdslichous: with four vertical ranks.
Thahim if droits : with the stamens, &c.

inserted in the receptacle, or
Thalamus: the receptacle of a flower.
Thallophytes, 37!, 505.
ThaUus, 67, 371, 505.
TJteca: an anther-cell, 281 ; or a spore-
case. 499, 500.
The'caphore : same as Gynophorc, 267.
Thread-shaped: sec Filiform, 166.
Throat: the orifice of a tubular organ,

275, 276.
Tliorn, 104.

T/up-se, or thyrsus: a (hick panicle, 217.
Thyrsoid: like a thyrsc.
Ttiymelaccae, 467
Tic'utc, 434.
Tiliacese, 399.

Tissue: the fabric of plants, 22.
Tobacco, 456.
Tomato, 456.
Tdmentose: clothed with
Tome'iUum: a close and matted down or

wool.
Tongue-shaped: long, fleshy, nearly flat,

and rounded at the end.
Tonka-bean, 414.

Tooth : any short and narrow projec-
tion.
Toothed: same as Dentate ; beset with
teeth which on the leaf do not point
forwards ; 159, fig 255.
Top-shaped : inversely conical
Torose: a cylindrical body swollen at in-
tervals.
Tortuous: bent in different directions.
Tdru/ose: somewhat torose.
Torus: the receptacle of the flower,

224.
Ti abe'culate : cross-barred.
Trachea : a spiral vessel or duct, 46.

Trarhc'nchyma, 46.

Trapezoid, or trapeziform : unsymmct-
lically four-sided, like a" trape-
zium.

Tree, 101.

Tri-, in compound words : three ; as

Triade'lplious: having the filaments in
three sets, 280.

Triandria, 512.

Tiidnchous: with three stamens, 279.

Triangular : three-angled.

Ti lanthous : three-flowered.

Tiibe, 361.

Tricdrpellary : of three carpels.

Tricdrj'ous : with three ovaries.

Trice'phalous : three-headed.

Trichdtomous : branched into threes.

Ti icdccous : of three cocci.

Tricuspidate : three-pointed.

Tnde'ntate : thrcc-toothed.

Triennial: lasting three years.

Tri furious: in three vertical ranks.

Ti'ijid: three-cleft ; 159, fig. 265.

Ti i foliate : three-leaved.

Trifd/iolate : of three leaflets.

Tri furcate : three-forked.

Tiiyanious : having three sorts of flowers.

Trigonal, or ti igonous : thiec-anglcd.

Trigynia, 515 '

Tiiijynous : with three pistils or styles,

, 287.
Trijugate : three-paired.
Ti /lateral : three-sided.
Trilliacero, 493.
Tn'ohale: threc-lobcd.
Trildcitlar : three-celled.
Ti iinerous : the parts in threes ; 234,

239, fig. 353.
Trine'i vate : three-nerved.
Trinddal : of three nodes or joints.
Trioeeia, 516.

Triacious, or trioicous : having stnmi-
nate, pistillate, and peifect flowers
on three different plants.
Tridrulafe : having three ovules.
Ti ipartilile : capable of splitting into

three.
Tripditite : three-parted.
Tiipe'talous : of three petals, 276.
Tiiphyilons : three-leaved, 275.
Tripinnate: thrice pinnate, 164.
Tiipinndtifid : thrice pinnatifid, 161.
Ti iple-rihhtd, or nerved : same as
Tripli-nerved, 155.
Ti ipterous : three-winged .
Trique'trous : with three salient angles.
Ti isepalons : of three sepals, 274.
Ti ise'nal, or trise'riate : in three horizon-
tal ranks.
Tristichous : in three vertical ranks, 134.
Ti istigmdtic : with three stigmas.
Tiistylous: with three styles.

GLOSSARY AND INDEX.

553

Trisu'lcate : three-grooved.

Trile'matc : thrice tcrnatc, 164.

Trivial name : the popular name ; or
the specific name.

Trochlear : pulley-shaped.

Tropasolnccsc, 404.

Trophosperm: the placenta.

Topical : growing near or between the
tropics.

Trumpet-shaped: tubular, with the sum-
mit dilated.

Truncate : as if cut off at the end ; 1 62,
fig. 271.

Trunk : a main stem.

Tube: the portion of a calyx, corolla,
&c. formed by the union of the
sepals, petals, &c, 275.

Tuber: a short and thickened subterra-
nean branch, 107.

Tubercle : a small tuber, or an excres-
cence.

Tubercled : bearing excrescences.

Tuba iferous : bearing tubers.

Tiibeious: tuber-like ; 85, fig. 139.

Tubulose, tubular : having a tube, or
tube-shaped, as the corolla of Trum-
pet Honeysuckle, &c, 277.

Tubuliflorai, 436.

Tumid: somewhat inflated.

Tunicate : having an accessory covering
(tunic).

Tnnicated bulb, 109.

Tuibinate: top-shaped.

Turio, lurions : the early state of a stick-
er or subterranean shoot, as an
Asparagus-shoot, 95.

Turmeric, 490.

Turneracea;, 422.

Turnip-shaped : see Napiform, 84.

Turnsole, 473.

Turpentine, 57, 480.

Twin : in pairs.

Twining : winding spirally round a sup-
port, 102.

Two-fij>j>ed, 255.

Type: the pattern or ideal plan, 231,
238.

Typhacere, 485.

Typical: representing the type or plan.

Uliginose: growing in marshes.

Ulmacca;, 474.

TJlniine, Ulmic Acid, 57.

Umbel: an umbrella-shaped inflores-
cence, 212.

Umbellate, umlelliform : in umbels.

Umbellet: a secondary or partial um-
bel, 216.

UmbellifersB, 425.

Umbelliferous : bearing timbels.

Umln'lieate: depressed in the centre,
like the navel.

47

Umbilicus: the hilum of a seed ; a ccn-

, tral depression.

Umbonate: bearing an umbo or boss,
a central projection.

Umln dculiform : umbrella-shnpcd.

Unarmed: destitute of prickles, spines,
&c.

Uncale: hooked.

U'nciform, or uncinate : hooked.

Undate, or undulate : wavy.

Undershiub, 101.

Unequally pinnate : same as impaii-pin-
natc, 163.

Unguiculate : furnished with a claw (un-
guis), as the petals of Saponaria,
276, fig 449, &c.

Uni-, in Latin compounds : one.

Unicellular : one-celled, 61.

Unifldrow : one-flowered.

Umfdliate : one-leaved.

Uiufdholate : with one leaflet.

Uni jugate: of only one pair, 164.

Untlubiute: one-lipped.

Unilateral: one-sided: either all dis-
posed on one side of an axis, or
turned to one side.

Unilocular : one-celled.

Umne'i rate : one-nerved.

Unidvulale : onc-ovulcd.

Unipe'talous : having only one petal, as
in Amorpha, fig. 395.

Unise'rial, or unise'riute: in one horizon-
tal row or whorl.

Unisexual: having stamens only or pis-

, tils only, 261.

Univaloed : of one piece ; onc-valvcd.

Universal : same as General.

Upas, 475.

Urceolate: pitcher-shaped or urn-shaped ;
i c. hollow and contracted at the
mouth.

Urtieacea:, 473.

Uhicle : a small bladdery fruit, 314.

Utricular : bladder-like.

Utriculariaccaj, or Utricnlarineas : same
as Lentibulaccaj, 445.

Utriculiform : shaped like a little bottle.

Utricu/ose: bearing utriculi, or bladders.

Uvulariete, 494.

Vaccinieoe, or Vncciniaccrc, 439.

Vagina : the sheath of a leaf, &c.

Vaginant: sheathing.

Vaginate : sheathed.

Vaginula : a little sheath, as that around

the sporangium of Peat Moss.
Vaginulate : with a vaginula.
Vague : in no definite order or direction.
Valerian, 434.
Valcrianaccce, 434.
Vallecula;: the intervals between tho

ridges of the fruit of Umbclliferaj.

554

GLOSSARY AND INDEX.

Valvate or valvular .•estivation, &c. :

where the parts meet by their edges

without overlapping, 144, 273.
Valve-: a door, or portion into which a

pod, &c. separates in dehiscence ;

also a piece or leaf of a spathc, &c.
Valued : opening by valves.
Vanilla, 489.
Variegated: having one or two colors

disposed in patches.
Varieties, 355.
Vascular ; relating to or furnished with

vessels.
Vascular Plants, G8.
Vascular or vasiform tissue, 40, 45.
Vasculum: same as Ascidimn.
Vegetable Ivory, 4S4.
Vegetable Physiology and Anatomy,

14.
Veil : see Calyptra.
Veined : furnished with slender vascular

or woody bundles, especially with

branching ones, or
Veins, 145, 155.

Vein/ess: destitute of apparent veins.
Veinlets : the smaller lamitications of

veins, 155.
Velate: veiled.
Velutinous : velvety ; covered with very

fine and close soft hairs, so that

the surface resembles velvet to the

touch.
Venation: the mode of vcining, 154.
Venose: veiny ; abounding in veins.
Ventral: relating to the inner side of a

simple pistil, viz. that next the

axis.
Ventral suture : the inner suture, 289.
Ve'nhicose: big-bellied; swelling out.
Vent) iculose : somewhat ventricosc.
Ve'nu/ose : abounding in veinlets.
Vcratria, 494.
Verbenacerc, 449.

Vermicular : worm-like, in shape or ap-
pearance.
Vernal : belonging to spring.
Vernation: the disposition of leaves in

the bud, 143.
Ve'micose : varnished.
Ve'rrucose: warty.

Ve'rruculose : studded with little warts.
Ve'rsatde: swinging to and fro; 282,

fig. 471.
Vertex : the summit.
Ve'rticaf : perpendicular, lengthwise.
Vet deal leaves, 165.
Vettical tissue or system, 45, 50, 112.
Ve'rticil, or v&ticel: a whorl, 92, 134.
Verticilldster : the pair of dense cymes
forming an apparent verticil in

most Labiatse, 221.
Verticillate : whorled, 133, 142, 221.

Vesicle: a little bladder.

Vesicular: as if composed of little blad-
deis.

Vespertine: appearing or expanding in
the early evening.

Vessels, 40.

Ve'tUtarg aestivation, 271.

Vecillaij: pertaining to the

Vadium: the standard of a papiliona-
ceous corolla ; 253, fig. 392, a.

Vtllose, ovvillous : shaggy with long and
soft hairs, or villosity.

Vimineous : bearing or resembling long
and flexible twigs, like wicker.

Vine: any trailing, climbing, or twining
stem. The Vine, originally, is the
Grape-vine.

ViolacctE, or Violarieap, 392.

Virescent: somewhat green (virens).

Vtajate: twig-like; wand-like.

Vnidescent : same as Virescent.

Viscid, viscous: sticky from a tena-
cious secretion.

Vitaccae, 407.

Vtle'dus : the thickened embryo-sac per-
sistent in the seed, as in Saururus
and Biascnia.

Viticulose: producing small suckers or
stolons (viticulte).

Vitt(e (fillets) : the oil-receptacles of the
fruit of Umbclliferac, 426.

Vitiate: bearing vittse : marked with
longitudinal stripes or fillets,
426.

Viviparous : germinating from the seed
(330), or sprouting from a bulb,
&c, while still attached to tho
parent plant.

Voluble: twining, 102.

Volute : rolled up.

Volca : the wrapper of Fungi, 507.

Walnut, 476.

Wavy: see Undulate.

Wax, 56.

Waxy : resembling beeswax in appear-
ance or consistence.

Wedi/e-shaped: see Cuncate.

Wheat, 498.

Wheel-shaped : a corolla or calyx with
a very short tube and a flat-
spreading border; 278, fig. 454.

Whorl. : a set of organs arranged in a
circle round an axis, 92, 134,
221.

Whoi led: disposed in whorls.

Whortleberry, 439.

Wild: growing spontaneously.

Wing: any membranous expansion.
Also the two side petals of a pa-
pilionaceous corolla ; 253, fig.
392, b.

GLOSSARY AND IXDF.X.

Winged: provided with wings.
Wintereso (or Wintcraccas), 381.
Winter's Baik, 381.

Withering: sec Marccsccnt.

Wood, 119.

Woody tissue or fibre, 40.

Woolly : clothed with long and curling,

or matted, .soft hairs or wool.
Worm-seed, 4G3.

Xyridaccffi, 49G.

Yam, 492.

Zanthoxylaeem, or Zantlioxylcae, 406.
Zingibcraccte, 489.

Zoospores: f'icc-moving spores of cer-
tain Al^a; ; 33G, iig. 637, G44.
Zygophyllaecte, 404.

THE END.

This book is a preservation facsimile.

It is made in compliance with copyright law

and produced on acid-free archival

60# book weight paper

which meets the requirements of

ANSI/NISO Z39.48-1992 (permanence of paper)

Preservation facsimile printing and binding

by

Acme Bookbinding

Charlestown, Massachusetts

B

2005