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BIOLOGY

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FRONTISPIECE. — A Shade Plant, Jack-in-tke-Pulpii

FOUNDATIONS OF BOTANY

JOSEPH Y. BERGEN, A.M.
V

INSTRUCTOR IN BIOLOGY, ENGLISH HIGH SCHOOL, BOSTON

BOSTON, U.S.A.

GINN & COMPANY, PUBLISHERS
&tbensettm
1901

r \.

BIOLOGY

LIBRARY

COPYBIGHT, 1901, BY
JOSEPH Y. BERGEN

PREFACE

THIS book is written upon the same plan as the author's
Elements of Botany. A few chapters stand here but little
altered from the former work, but most of them have been
rewritten and considerably enlarged, and many new ones
have been added. The principal changes in the book as a
whole are these :

1. Most of the discussion of ecological topics is put by
itself, in Part II.

2. The amount of laboratory work on the anatomy and
physiology of seed-plants is considerably increased and addi-
tional experiments are introduced.

3. The treatment of spore-plants is greatly extended, so as
to include laboratory work on the most important groups.

4. The meagre Flora which accompanied the earlier book
has been replaced by one which contains fairly full descrip-
tions of nearly seven hundred species of plants. Most of
these are wild, but a considerable number of cultivated species
have been included, mainly for the convenience of schools in
large cities.

Ample material is offered for a year's course, four or five
periods per week. The author is well aware that most schools
devote but half a year to botany, but the tendency sets strongly
toward allowing more time for this subject. Even in schools
where the minimum time allowance is devoted to botany, there
is a distinct advantage in being provided with a book which
allows the teacher considerable option as regards the kind
and amount of work which he shall offer to his classes.

iv PREFACE

Suggestions are made in the teacher's Handbook, which
accompanies this volume, in regard to shaping half-year
courses.

The latest authorities in the various departments of botany
have been consulted on all doubtful points, and the attempt
has been to make the book scientifically accurate throughout,
yet not unduly difficult.

Most of the illustrations have been redrawn from those in
standard German works of an advanced character, or drawn
from nature or from photographs, expressly for this book.
Besides the sources of drawings acknowledged in the author's
Elements, many cuts have been taken from the botanies of
Frank, Prantl, Detmer, Murray, and Bennett and Murray, as
well as from Schimper's Pflanzengeographie.

Of the drawings from nature or from photographs, some
figures, and Plates I, VII, and VIII, are by Mr. Edmund
Garrett of Boston ; several figures, the Frontispiece, and
Plates II, IV, X, XI, are by Mr. Bruce Horsfall of New York ;
several figures are by Mr. F. Schuyler Mathews of Boston ; a
large number of figures and Plate V are by Mr. E. N. Fischer
of Boston; several figures are by Mr. E. B,. Kingsbury of Boston
and Dr. J. W. Folsom of the University of Illinois.

Thanks for the use of photographs are due to Mr. H. G.
Peabody of Boston (Fig. 234), to Mr. J. H. White of Boston
(Figs. 32, 75, 222), to Professor Conway MacMillan of the Uni-
versity of Minnesota (Frontispiece), and to Professor F. V.
Coville of Washington (Plate VII). Figs. 28 and 275 are
taken by permission from the Primer of Forestry, issued by the
Division of Forestry, U. S. Department of Agriculture. Figs.
263, 264, 276 are copied by permission from Professor W. J.
Beal's Seed Dispersal, and Figs. 226, 229, 233 from Professor
W. M. Davis's Physical Geography. Fig. 269 is from a photo-
graph by Professor C. F. Millspaugh of the Field Columbian
Museum, Chicago.

PREFACE V

Most of the redrawn illustrations (not microscopical) from
various European sources are by Mr. Fischer. Most of the
microscopical ones (and a number of figures from nature) are
by Dr. J. W. Folsom of the University of Illinois, and many
of both classes are by Mr. Mathews. Thanks are due to
Professor J. M. Holzinger of the Winona (Minn.) State
Normal School, to Professor L. Murbach of the Detroit High
School, and to Mr. I. S. Cutter of Lincoln, Nebraska, for
their many discriminating criticisms of the proof of Parts I
and II. Mr. Samuel F. Tower of the Boston English High
School, Professor Charles V. Piper of the Washington State
Agricultural College, and Dr. Rodney H. True, Lecturer on
Botany at Harvard University, have all read the whole or
large portions of Part I and given valuable suggestions.
Professor W. F. Ganong, of Smith College, has read and
criticised Part II.

The chapters on spore-plants, excepting a small amount of
matter retained from the Elements of Botany, are entirely the
work of Mr. A. B. Seymour of the Cryptogamic Herbarium of
Harvard University.

The author has attempted to steer a middle course between
the advocates of the out-of-door school and of the histological
school of botany teaching. He has endeavored never to use a
technical term where he could dispense with it, and on the
other hand, not to become inexact by shunning necessary
terms. In deciding questions of this sort, a priori reasoning
is of little value ; one must ascertain by repeated trials how
much of a technical vocabulary the average beginner in botany
can profitably master. The teacher who has discovered that
not one of the boys in a division of thirty-six pupils knows
that his own desk-top is of cherry wood may well hesitate
about beginning his botany teaching with a discourse on cen-
trospheres and karyokinesis. It has been assumed throughout
this book that, other things being equal, the knowledge is of

VI PREFACE

most worth, which touches the pupil's daily life at the most
points, and therefore best enables him to understand his own
environment. On the other hand, the author has no sympathy
with those who decry the use of apparatus in botany teaching
in secondary schools and who would confine the work of their
pupils mainly within the limits of what can be seen with the
unaided eye. If the compound microscope plainly reveals
things shown only imperfectly by a magnifier and not seen at
all with the naked eye, — use the microscope ! If iodine
solution or other easily prepared reagents make evident the
existence of structures or substances not to be detected with-
out them, — then use the reagents ! No one thinks of deny-
ing a boy the use of a spyglass or a compass for his tramps
afield or his outings in a boat because he has not studied
physics. No one would refuse to let an intelligent boy or
girl use a camera because the would-be photographer had not
mastered the chemical reactions that follow upon the expo-
sure of a sensitized plate. Yet it is equally illogical to defer
some of the most fascinating portions of botanical study until
the college course, to which, most never attain. When the
university professor tells the teacher that he ought not to
employ the ordinary appliances of elementary biological inves-
tigation in the school laboratory because the pupils cannot
intelligently use them, the teacher is forced to reply that the
professor himself cannot intelligently discuss a subject of
which he has no personal knowledge. The pupils are deeply
interested; they prove by their drawings and their recita-
tions that they have seen a good way into plant structures
and plant functions ; . then why not let them study botany
in earnest ?

J. Y. B.
CAMBRIDGE, January, 1901.

CONTENTS

PART I

STRUCTURE, FUNCTIONS, AND CLASSIFICATION OF PLANTS

CHAPTER I
THE SEED AND ITS GERMINATION ...... 5-13

CHAPTER II
STORAGE OF FOOD IN THE SEED ...... 14-24

CHAPTER III
MOVEMENTS, DEVELOPMENT, AND MORPHOLOGY OF THE SEEDLING 25-35

CHAPTER IV
ROOTS . 36-61

CHAPTER V
STEMS . • 62-82

CHAPTER VI
STRUCTURE OF THE STEM ........ 83-103

CHAPTER VII
LIVING PARTS OF THE STEM , WORK OF THE STEM . . , 104-118

CHAPTER VIII

BUDS 119-129

vii

Vlll CONTENTS

CHAPTER IX PAGES

LEAVES 130-139

CHAPTER X

LEAF-ARRANGEMENT FOR EXPOSURE TO SUN AND AIR ; MOVE-
MENTS OF LEAVES AND SHOOTS ...... 140-149

CHAPTER XI
MINUTE STRUCTURE OF LEAVES ; FUNCTIONS OF LEAVES . . 150-177

CHAPTER XII
PROTOPLASM AND ITS PROPERTIES ...... 178-185

CHAPTER XIII
INFLORESCENCE, OR ARRANGEMENT OF FLOWERS ON THE STEM 186-191

CHAPTER XIV
THE STUDY OF TYPICAL FLOWERS 192-196

CHAPTER XV
PLAN AND STRUCTURE OF THE FLOWER AND ITS ORGANS . 197-207

CHAPTER XVI

TRUE NATURE OF FLORAL ORGANS ; DETAILS OF THEIR STRUC-
TURE ; FERTILIZATION ........ 208-216

CHAPTER XVII
THE STUDY OF TYPICAL FRUITS ...... 217-220

CHAPTER XVIII
THE FRUIT 221-227

CHAPTER XIX

THE CLASSIFICATION OF PLANTS .,,..• 228-234

CONTENTS

CHAPTER XX
TYPES OF CRYPTOGAMS ; THALLOPHYTES .

'CHAPTER XXI
TYPES OF CRYPTOGAMS; BRYOPHYTES

CHAPTER XXII
TYPES OF CRYPTOGAMS; PTERIDOPHYTES .

CHAPTER XXIII
THE EVOLUTIONARY HISTORY OF PLANTS .

PAGES
. 235-276

. 277-285

. 286-297

. 298-305

PART II

ECOLOGY, OB RELATIONS OP PLANTS TO THE WORLD
ABOUT THEM

CHAPTER XXIV
PLANT SOCIETIES 307-323

CHAPTER XXV
BOTANICAL GEOGRAPHY . . . . . . . . 324-335

CHAPTER XXVI
PARASITES, ENSLAVED PLANTS, MESSMATES, CARNIVOROUS PLANTS 336-344

CHAPTER XXVII
How PLANTS PROTECT THEMSELVES FROM ANIMALS . . 345-352

CONTENTS

CHAPTER XXVIII

PAGKS

ECOLOGY OF FLOWERS ... . 353-372

CHAPTER XXIX
How PLANTS ARE SCATTERED AND PROPAGATED . . . 373-386

CHAPTER XXX

THE STRUGGLE FOR EXISTENCE AND THE SURVIVAL OF THE

FITTEST . 387-395

LIST OF PLATES

FRONTISPIECE. Jack-in-the-pulpit, a typical shade-plant, with large,
thin leaves.

Facing page

PLATE I. Sand-dunes with sea rye grass. Deep-rooted, with exten-
sively running rootstocks . 76

PLATE II. Pollarded willows, showing growth of slender twigs from

adventitious buds . . .... . . . . 128

PLATE III. Japanese ivy, a tendril-climber growing on face of a
building, showing leaves all exposed to sunlight at the most
advantageous angle . . 140

PLATE IV. Cypress swamp, showing " Spanish moss " (Tillandsia)?
a phanerogamic epiphyte practically leafless, the work ordinarily
done by leaves devolving on the slender stems. The cypress
trees are furnished with " knees " or projections from the roots,
which are thought by some to absorb air . . . . .158

PLATE V. Indian pipe, a saprophytic seed-plant, wholly destitute

of chlorophyll and with scales instead of foliage leaves . . 168

PLATE VI. Fan palms, showing general habit of the tree, and large
projecting bases of old petioles left after the decay of the leaves 176

PLATE VII. A tree yucca in the Mohave Desert, a characteristic

xerophytic tree. Other sparse desert vegetation is also shown . 316

PLATE VIII. Belt of trees along a Nebraskan river, showing depend-
ence of forest on water supply 334

PLATE IX. Cottonwood. Tree largely overgrown with American
mistletoe, near Mesilla, New Mexico. The photograph was taken
in whiter, when the tree was leafless, so that all the foliage shown
is that of the mistletoe 336

PLATE X. Humming-bird visiting flowers of the trumpet creeper.
This is one of the best North American examples of a flower
mainly pollinated by birds 362

PLATE XI. Asters and golden-rods, Compositse, illustrating the
principle of grouping many small flowers into heads (and in
the golden-rod the heads into rather close clusters) to facilitate
the visits of insects . . 372

FOUNDATIONS OF BOTANY

INTRODUCTION

" Botany is the science which endeavors to answer every reason-
able question about plants." l

THE plant is a living being, provided generally with
many parts, called organs-, which it uses for taking in nour-
ishment, for breathing, for protection against its enemies,
and for reproducing itself and so keeping up the numbers
of its own kind. The study of the individual plant there-
fore embraces a variety of topics, and the examination of
its relation to others introduces many more subjects.

Morphology, or the science of form, structure, and so on,
deals with the plant without much regard to its character
as a living thing. Under this head are studied the forms
of plants and the various shapes or disguises which the
same sort of organ may take in different kinds of plants,
their gross structure, their microscopical structure, their
classification, and the successive stages in the develop-
ment of the individual plant.

Plant Physiology treats of the plant in action, how it lives,
breathes, feeds, grows, and produces others like itself.

Geographical Distribution, or botanical geography, dis-
cusses the range of the various kinds of plants over the

1 Professor George L. Goodale.

2 FOUNDATION'S OF BOTANY

earth's surfaced Another subdivision of botany, usually
studied along witfe geology, describes the history of plant
life on the earth from the appearance of the first plants
until the present time.

L Systematic Botany, or the classification of plants, should
naturally follow the examination of the groups of seed-
plants and spore-plants.

Plant Ecology treats of the relations of the plant to
the conditions under which it lives. Under this division
of the science are studied the effects of soil, climate, and
friendly or hostile animals and plants on the external
form, the internal structure, and the habits of plants.
This is in many respects the most interesting department
of botany, but it has to be studied for the most part out
of doors.

Many of the topics suggested in the above outline cannot
well be studied in the high school. There is not usually
time to take up more than the merest outline of botanical
geography, or to do much more than mention the impor-
*-" tant subject of Economic Botany — the study of the uses
of plants to man. It ought, however, to be possible for
the student to learn in his high-school course a good deal
about the simpler facts of morphology and of vegetable
physiology. One does not become a botanist — not even
much of an amateur in the subject — by reading books
about botany. It is necessary to study plants themselves,
to take them to pieces and make out the connection of their
parts, to examine with the microscope small portions of the
exterior surface and thin slices of all the variously built
materials or tissues of which the plant consists. All this
can be done with living specimens or with those taken

INTRODUCTION 6

from dead parts of plants that have been preserved in any
suitable way, as by drying or by placing in alcohol or other
fluids which prevent decay. Living plants must be studied
in order to ascertain what kinds of food they take, what
kinds of waste substances they excrete, how and where
their growth takes place and what circumstances favor it,
how they move, and indeed to get as complete an idea as
possible of what has been called the behavior of plants.

Since the most familiar and most interesting plants
spring from seeds, the beginner in botany can hardly do
better than to examine at the outset the structure of a few
familiar seeds, then sprout them and watch the growth of
the seedlings which spring from them. Afterwards he
may study in a few typical examples the organs, structure,
and functions of seed-plants, trace their life history, and
so, step by step, follow the process by which a new crop
of seeds at last results from the growth and development
of such a seed as that with which he began.

After he has come to know in a general way about the
structure and functions of seed-plants, the student may
become acquainted with some typical cryptogams or spore-
plants. There are so many groups of these that only a
few representative ones can be chosen for study.

PART I

STRUCTURE, FUNCTIONS, AND CLASSIFI-
CATION OF PLANTS

CHAPTER I

THE SEED AND ITS GERMINATION

1. Germination of the Squash Seed. — Soak some squash seeds in
tepid water for twelve hours or more. Plant these about an inch
deep in damp sand or pine sawdust or peat-moss in a wooden box
which has had holes enough bored through the bottom so that it will
not hold water. Put the box in a warm place (not at any time over
70° or 80° Fahrenheit),1 and cover it loosely with a board or a pane
of glass. Keep the sand or sawdust moist, but not wet, and the
seeds will germinate. As soon as any of the seeds, on being dug up,
are found to have burst open, sketch one in this condition,2 noting
the manner in which the outer seed-coat is split, and continue to
examine the seedlings at intervals of two days, until at least eight
stages in the growth of the plantlet have been noted.3

1 Here and elsewhere throughout the book temperatures are expressed in
Fahrenheit degrees, since with us, unfortunately, the Centigrade scale is not
the familiar one, outside of physical and chemical laboratories.

2 The student need not feel that he is expected to make finished drawings
to record what he sees, but some kind of careful sketch, if only the merest
outline, is indispensable. Practice and study of the illustrations hereafter
given will soon impart some facility even to those who have had little or no
instruction in drawing. Consult here Figs. 9 and 89.

3 The class is not to wait for the completion of this work (which may, if
desirable, be done by each pupil at home), but is to proceed at once with the
examination of the squash seed and of other seeds, as directed in the follow-
ing sections, and to set some beans, peas, and corn to sprouting, so that they
may be studied at the same time with the germinating squashes.

FOUNDATIONS OF BOTANY

— t

\—-e

Observe' particularly how the sand is pushed aside by the rise of
the young seedlings. Suggest some reason for the manner in which
the sand is penetrated by the rising stem.

2, Examination of the Squash Seed. —
Make a sketch of the dry seed, natural size.
Note the little scar at the pointed end of the
seed where the latter was attached to its
place of growth in the squash. Label this
hilum.

Note the little hole in the hilum ; it is
the micropyle, seen most plainly in a soaked
seed. (If there are two depressions on the
hilum the deeper one is the micropyle.)

Describe the color and texture of the outer
coating of the seed. With a scalpel or a very
sharp knife cut across near the middle a seed
that has been soaked in water for twenty-
four hours. Squeeze one of the portions,
held edgewise between the thumb and finger,
in such a way as to separate slightly the
halves into which the contents of the seed is
naturally divided. Examine with the mag-
nifying glass the section thus treated, make
a sketch of it, and label the shell or covering
of the seed and the kernel within this.

Taking another soaked seed, chip away
the white outer shell, called the testa, and
observe the thin, greenish inner skin (Fig.
1, e), with which the kernel of the seed is
closely covered.1

Strip this off and sketch the uncovered ker-
nel or embryo. Note that at one end it tapers
to a point. This pointed portion, known
as the hypocotyl, will develop after the seed
sprouts into the stern of the plantlet, like that shown at c in Fig. 2.
Split the halves of the kernel entirely apart from each other,

cot.

— c

FIG. 1.— Lengthwise Section
of a Squash Seed. (Magni-
fied about five times.)

See footnote 2 to Sect. 18.

THE SEED AND ITS GERMINATION

noticing that they are only attached for a very little way next to
the hypocotyl, and observe the thickness of the halves and the slight
unevenness of the inner surfaces. These halves are called seed-leaves
or cotyledons.

Have ready some seeds which have been soaked for twenty-four
hours and then left in a loosely covered jar on damp blotting paper
at a temperature of 70° or over
until they have begun. to sprout.

Split one of these seeds apart,
separating the cotyledons, and
observe, at the junction of these,
two very slender pointed objects,
the rudimentary leaves of the
plumule or first bud (Fig. 1, p).

3. Examination of the Bean.
— Study the seed, both dry and
after twelve hours' soaking, in
the same general way in which
the squash seed has just been
examined.1

Notice the presence of a dis-
tinct plumule, consisting of a pair
of rudimentary leaves between
the cotyledons, just where they

are joined to the" top of the hypo- FlG 2. — The Castor Bean and its

Germination.

cotyl. In many seeds (as the pea)
the plumule does not show dis-
tinct leaves. But in all cases
the plumule contains the growing
point, the tip of the stem from
which all the upward growth of
the plant is to proceed.

Make a sketch of these leaves as they lie in place on one of the
cotyledons, after the bean has been split open.

1 The larger the variety of bean chosen, the easier it will be to see and
sketch the several parts. The large red kidney bean, the horticultural bean,
or the lima bean will do well for this examination.

A, longitudinal section of ripe seed ; t,
testa ; co, cotyledon ; c, hypocotyl ;
B, sprouting seed covered with endo-
sperm ; C, same, with half of endo-
sperm removed ; D, seedling ; r, pri-
mary root ; r', secondary roots ; c, arch
of hypocotyl.

8 FOUNDATIONS OF BOTANY

Note the cavity in each cotyledon caused by the pressure of the
plumule and of the hypocotyl.

4.^ Examination of the Pea. — There are no very important points
of difference between the bean and pea, so far as the structure of
the seed is concerned, but the student should rapidly dissect a few-
soaked peas to get an idea of the appearance of the parts, since he
is to study the germination of peas in some detail.

Make only one sketch, that of the hypocotyl as seen in position
after the removal of the seed-coats.1

5. Germination of the Bean or the White Lupine, the Pea, and the
Grain of Corn. — Soak some beans or lupine seeds as directed in
Section 3, plant them,2 and make a series of sketches on the same
general plan as those in Fig. 9.

Follow the same directions with some peas and some corn. In the
case of the corn, make six or more sketches at various stages to illus-
trate the growth of the plumule and the formation of roots ; first a
main root from the base of the hypocotyl, then others more slender
from the same region, and later on still others from points higher
up on the stem (see Fig. 15). The student may be able to dis-
cover what becomes of the large outer part of the embryo. This is
really the single cotyledon of the corn (Fig. 6). It does not as a
whole rise above ground, but most of it remains in the buried grain,
and acts as a digesting and absorbing organ through which the
endosperm, or food stored outside of the embryo is transferred into
the growing plant, as fast as it can be made liquid for that purpose.

6. Germination of the Horse-Chestnut . — Plant some seeds of the
horse-chestnut or the buckeye, study their mode of germination, and
observe the nature and peculiar modifications of the parts.

Consult Gray's Structural Botany, Vol. I, pp. 19, 20.

/ 7. Conditions Requisite for Germination. — When we
try to enumerate the external conditions which can affect

1 The teacher will find excellent sketches of most of the germinating seeds
described in the present chapter in Miss Newell's Outlines of Lessons in
Botany, Part I.

2 The pupil may economize space by planting the new seeds in boxes
from which part of the earlier planted seeds have been dug up for use in
sketching, etc.

THE SEED AND ITS GERMINATION 9

germination, we find that the principal ones are heat,
moisture, and presence of air. A few simple experiments
will show \vhat influence these conditions exert.

8. Temperature. — Common observation shows that a
moderate amount of warmth is necessary for the sprout-
ing of seeds. Every farmer or gardener knows that
during a cold spring many seeds, if planted, will rot in
the ground. But a somewhat exact experiment is neces-
sary to show what is the best temperature for seeds to
grow in, and whether variations in the temperature make
more difference in the quickness with which they begin
to germinate or in the total per cent which finally succeed.

EXPERIMENT I

Relation of Temperature to Germination. — Prepare at least four
teacups or tumblers, each with wet soft paper packed in the bottom
to a depth of nearly an inch. Have a tightly fitting cover over each.
Put in each vessel the same number of soaked peas. Stand the ves-
sels with their contents in places where they will be exposed to dif-
ferent, but fairly constant, temperatures, and observe the several
temperatures carefully with a thermometer. Take pains to. keep the
tumblers in the warm places from drying out, so that their contents
will not be less moist than that of the others. The following series
is merely suggested, — other values may be found more convenient.
Note the rate of germination in each place and record in tabular
form as follows :

No. of seeds sprouted in 24 hrs. 48 hrs. 72 hrs. 96 hrs. etc.
At 32°,
At 50°,
At 70°,
At 900,1

1 For the exact regulation of the temperatures a thermostat (see Handbook)
is desirable. If one is available, a maximum temperature of 100° or over
should be tried.

FOUNDATIONS OF BOTANY

9, Moisture. — What was said in thejDreceding section
in regard to temperature applies also to the question of
the best conditions for germination as regards the supply
of moisture. The soil in which seeds grow out of doors
is always moist; it rests with the experimenter to find
out approximately what is the best amount of moisture.

EXPERIMENT II1

Relation of Water to Germination. — Arrange seeds in several
vessels as follows :

In the first put blotting paper that is barely moistened ; on this
put some dry seeds.

In the second put blotting paper that has been barely moistened ;
on this put seeds that have been soaked for twenty-four hours.

In the third put
water enough to soak
the paper thor-
oughly; use soaked

In the fourth put
water enough to half
cover the seeds.

Place the vessels
where they will have
same temperature and
note the time of ger-
mination.

Tabulate your re-
sults as in the previ-
ous experiment.

10, Relation of the Air Supply to Germination. — If we
wish to see how soaked seeds will behave with hardly any
air supply, it is necessary to place them in a bottle arranged

1 This may be made a home experiment.

FIG. 3. — Soaked Peas in Stoppered Bottle, ready
for Exhaustion of Air.

THE SEED AND ITS GERMINATION 11

as shown in Fig. 3, exhaust the air by connecting the glass
tube with an air-pump, which is then pumped vigorously,
and seal the tube while the exhaustion is going on. The
sealing is best done by holding a Bunsen flame under the
middle of the horizontal part of the tube. A much easier
experiment, which is nearly as satisfactory, can, however,
be performed without the air-pump.

EXPERIMENT III

Will Seeds Germinate well without a Good Supply of Air? —

Place some soaked seeds on damp blotting paper in the bottom of a
bottle, using seeds enough to fill it three-quarters full, and close
tightly with a rubber stopper.

Place a few other seeds of the same kind in a second bottle;
cover loosely.

Place the bottles side by side, so that they will have the same
conditions of light and heat. Watch for results, and tabulate as in
previous experiments.

Most seeds will not germinate under water, but those of the
sunflower will do so, and therefore Exp. Ill may be varied in the
following manner :

Remove tlje shells carefully from a considerable number of sun-
flower seeds.1 Try to germinate one lot of these in water which has
been boiled in a flask to remove the air, and then cooled in the
same flask. Over the water, with the seeds in it, a layer of cotton-
seed oil about a half inch deep is poured, to keep the water from
contact with air. In this bottle then there will be only seeds and
air-free water. Try to germinate another lot of seeds in a bottle
half filled with ordinary water, also covered with cotton-seed oil.
Results?

11. Germination involves Chemical Changes. — If a ther-
mometer is inserted into a jar of sprouting seeds, for

1 These are really fruits, but the distinction is not an important one at
this time.

12 FOUNDATIONS OF BOTANY

instance peas, in a room at the ordinary temperature, the
peas will be found to be warmer than the surrounding
air. This rise of temperature is at least partly due to
the absorption from the air of that substance in it which
supports the life of animals and maintains the burning of
fires, namely, oxygen.

The union of oxygen with substances with which it
can combine, that is with those which will burn, is called
oxidation. This kind of chemical change is universal in
plants and animals while they are in an active condition,
and the energy which they manifest in their growth and
movements is as directly the result of the oxidation going
on inside them as the energy of a steam engine is the
result of the burning of coal or other fuel under its boiler.
In the sprouting seed much of the energy produced by
the action of oxygen upon oxidizable portions of its con-
tents is expended in producing growth, but some of this
energy is wasted by being transformed into heat which
escapes into the surrounding soil. It is this escaping
heat which is detected by a thermometer thrust into a
quantity of germinating seeds.

EXPERIMENT IV

Effect of Germinating Seeds upon the Surrounding Air. — When
Exp. Ill has been finished, remove a little of the air from above the
peas in the first bottle. This can easily be done with a rubber bulb
attached to a short glass tube. Then bubble this air through some
clear, filtered limewater. Also blow the breath through some lime-
water by aid of a short glass tube. Explain any similarity in
results obtained. (Carbon dioxide turns limewater milky.) After-
wards insert into the air above the peas in the same bottle a lighted
pine splinter, and note the effect upon its flame.

THE SEED AND ITS GERMINATION 13

12. Other Proofs of Chemical Action. — Besides the proof ->, t ^
of chemical changes in germinating seeds just described, ^^
there are other kinds of evidence to the same effect.

Malt, which is merely sprouted barley with its germi-
nation permanently stopped at the desired point by the
application of heat, tastes differently from the unsprouted
grain, and can be shown by chemical tests to have suffered
a variety of changes. If you can get unsprouted barley
and malt, taste both and see if you can decide what sub-
stance is more abundant in the malt.

Germinating kernels of corn undergo great alterations
in their structure ; the starch grains are gradually eaten
away until they are ragged and full of holes and finally
disappear.

13. The Embryo and its Development. — The miniature
plant, as it exists ready formed and alive but inactive in
the seed, is called the embryo. In the seeds so far ex-
amined, practically the entire contents of the seed-coats
consist of the embryo, but this is not the case with the
great majority of seeds, as will be shown in the following
chapter.

CHAPTER II
STORAGE OF FOOD IN THE SEED

14. Food in the Embryo. — Squash seeds are not much
used for human food, though both these and melon seeds
are occasionally eaten in parts of Europe ; but beans and
peas are important articles of food. Whether the material
accumulated in the cotyledons is an aid to the growth of
the young plant may be learned from a simple experiment.

15. Mutilated and Perfect Seedlings. — One of the best
ways in which to find out the importance and the special

use of any part of
a plant is to re-
move the part in
question and see
how the plant be-
haves afterward.

EXPERIMENT V1

Are the Cotyledons
of a Pea of any Use
to the Seedling ? —

Sprout several peas on
FIG. 4. -Germinating Peas, growing in Water, one blotting aper> When
deprived of its Cotyledons.

the plumules appear,

carefully cut away the cotyledons from some of the seeds. Place on
a perforated cork, as shown in Fig. 4, one or two seedlings from

1 May be a home experiment.
14

STORAGE OF FOOD IN THE CELLS 15

which the cotyledons have been cut, and as many which have not
been mutilated, and 'allow the roots to extend into the water. Let
them grow for some days, or even weeks, and note results.

16. Food stored in Seeds in Relation to Growth after

Germination If two kinds of seeds of somewhat similar

character, one kind large and the other small, are allowed
to germinate and grow side by side, some important infer-
ences may be drawn from their relative rate of growth.

EXPERIMENT VI1

Does the Amount of Material in the Seed have anything to do with
the Rate of Growth of the Seedling ? — Germinate ten or more
clover seeds, and about the same number of peas, on moist blotting
paper under a bell-jar. After they are well sprouted, transfer both
kinds of seeds to fine cotton netting, stretched across wide-mouthed
jars nearly full of water. The roots should dip into the water, but
the seeds must not do so. Allow the plants to grow until the peas
are from four to six inches high.

Some of the growth in each case depends on material
gathered from the air and water, but most of it, during the
very early life of the plant, is due to the reserve material
stored in the seed. Where is it in
the seeds so far studied ? Proof ?

17. Storage of Food outside of
the Embryo. — In very many cases
the cotyledons contain little food,

but there is a Supply of it Stored FIG. 5. — Seeds with Endosperm,
, , , . , -1,1 Longitudinal Sections.

in the seed beside or around them

I, asparagus (magnified).
(FlgS. 2, 5, aild 6). II, poppy (magnified).

18. Examination of the Four-o'clock Seed. — Examine the exter-
nal surface of a seed2 of the four-o'clock, and try the hardness of

1 May be a home experiment. 2 Strictly speaking, a fruit.

FOUNDATIONS OF BOTANY

the outer coat by cutting it with a knife. From seeds which have
been soaked in water at least twenty-four hours peel off the coatings
and sketch the kernel. Make a cross-section of one of the soaked
seeds which has not been stripped of its coatings, and sketch the sec-
tion as seen with the magnifying glass, to show the parts, especially
the two cotyledons, lying in close contact and encircling the white,
starchy-looking endosperm.1

The name endosperm is applied to food stored in parts of the
seed other than the embryo.2 With a mounted needle pick out the
little almost spherical mass of endosperm from inside the cotyledons
of a seed which has been deprived of
its coats, and sketch the embryo, noting
how it is curved so as to enclose the
endosperm almost completely.

19, Examination of the- Kernel of In-
dian Corn. — Soak some grains of large
yellow field corn 3 for about three days.

Sketch an unsoaked kernel, so as to
show the grooved side, where the germ
lies. Observe how this groove has be-
come partially filled up in the soaked
kernels.

Remove the thin, tough skin from

FIG. 6. — Lengthwise Section of

Grain of Corn. (Magnified

about three times.)

tion of food from it ; r,
primary root.

„, yellow, oily part of endosperm-, one of the latter, and notice its transpar-
w, white, starchy part of en- ency. This skin — the bran of unsifted
dosperm ; p, plumule ; *, the CQrn meal _ doeg not exactly correspond
shield (cotyledon), in contact .

with the endosperm f or absorp- to the testa and inner coat of ordinary
the seeds, since the kernel of corn, like all
other grains (and like the seed of the
four-o'clock), represents not merely the seed, but also the se,ed-vessel
in which it was formed and grew, and is therefore a fruit. /

1 Buckwheat furnishes another excellent study in seeds with endosperm.
Like that of the four-o'clock, it is, strictly speaking, a fruit ; so also is a grain
of corn.

2 In the squash seed the green layer which covered the embryo represents
the remains of the endosperm.

3 The varieties with long, flat kernels, raised in the Middle and Southern
States under the name of " dent corn," are the best.

STORAGE OF FOOD IX THE SEED 17

Cut sections of the soaked kernels, some transverse, some length-
wise and parallel to the flat surfaces, some lengthwise and at right
angles to the flat surfaces. Try the effect of staining some of these
sections with iodine solution.

Make a sketch of one section of each of the three kinds, and label
the dirty white portion, of cheesy consistency, embryo ; and the yel-
low portions, and those which are white and floury, endosperm.

Chip off the endosperm from one kernel so as to remove the
embryo free from other parts.1 Notice its form, somewhat triangular
in outline, sometimes nearly the shape of a beechnut, in other speci-
mens nearly like an almond.

Estimate what proportion of the entire bulk of the soaked kernel
is embryo.

Split the embryo lengthwise so as to show the slender, somewhat
conical plumule.2

20. Corn Seedlings deprived of Endosperm — An experi-
ment parallel to No. V serves to show the function and
the importance of the endosperm of Indian corn.

EXPERIMENT VII

Of how much Use to the Corn Seedling is the Endosperm ? — Sprout
kernels of corn on blotting paper. When they get fairly started,
cut away the endosperm carefully from several of the seeds. Sus-
pend on mosquito netting on the surface of water in the same jar
two or three seedlings which have had their endosperm removed, and
as many which have not been mutilated. Let them grow for some
weeks, and note results.

21. Starch Most common seeds contain starch.

Every one knows something about the appearance of ordi-

1 The embryo may be removed with great ease from kernels of rather ma-
ture green corn. Boil the corn for about twenty minutes on the cob, then pick
the kernels off one by one with the point of a knife. They may be preserved
indefinitely in alcohol of 50 or 75%.

2 The teacher may well consult Figs. 56-61, inclusive, in Gray's Structural
Botany.

18 FOUNDATIONS OF BOTANY

nary commercial starch as used in the laundry, and as
sold for food in packages of cornstarch. When pure it
is characterized not only by its lustre, but also by its
peculiar velvety feeling when rubbed between the fingers.

22. The Starch Test It is not always easy to recog-
nize at sight the presence of starch as it occurs in seeds,
but it may be detected by a very simple chemical test,
namely, the addition of a solution of iodine.1

EXPERIMENT VIII2

Examination of Familiar Seeds with Iodine. — Cut in two with a
sharp knife the seeds to be experimented on, then pour on each, drop
by drop, some of the iodine solution. Only a little is necessary;
sometimes the first drop is enough.

If starch is present, a blue color (sometimes almost black) will
appear. If no color is obtained in this way, boil the pulverized
seeds for a moment in a few drops of water, and try again.

Test in this manner corn, wheat (in the shape of flour), oats (in
oatmeal), barley, rice, buckwheat, flax, rye, sunflower, four-o'clock,
morning-glory, mustard seed, beans, peanuts, Brazil-nuts, hazelnuts,
and any other seeds that you can get. Report your results in tabu-
lar form as follows : .

MUCH STARCH LITTLE STARCH No STARCH

Color : blackish or Color : pale blue or Color : brown, orange,
, dark blue. greenish. or yellowish.

23. Microscopical Examination of Starch.3 — Examine starch in
water with a rather high power of the microscope (not less than 200
diameters).

1 The tincture of iodine sold at the drug-stores will do, but the solution
prepared as directed in the Handbook answers better. This may be made up
in quantity, and issued to the pupils in drachm vials, to be taken home and
used there, if the experimenting must be done outside of the laboratory or the
schoolroom. 2 May be a home experiment.

8 At this point the teacher should give a brief illustrated talk on the con-
struction and theory of the compound microscope.

STORAGE OF FOOD IN THE SEED

Pulp scraped from a potato, that from a canna rootstock, wheat
flour, the finely powdered starch sold under the commercial name of
"cornstarch" for cooking, oat-
meal, and buckwheat finely pow-
dered in a mortar, will furnish
excellent examples of the shape
and markings of starch grains.
Sketch all of the kinds exam-
ined, taking pains to bring out
the markings.1 Compare the
sketches with Figs. 7 and 8.

With a medicine-dropper or a
very small pipette run in a drop FIG. 7. — Canna starch. (Magnified
of iodine solution under one edge

of the cover-glass, at the same time withdrawing a little water from
the margin opposite by touching to it a bit of blotting paper.

FIG. 8. — Section through Exterior Part of a Grain of Wheat.

c, cuticle or outer layer of bran ; ep, epidermis ; m, layer beneath epidermis ; gu,
sch, layers of hull next to seed-coats ; br, n, seed-coats ; Kl, layer containing
proteid grains ; st, cells of the endosperm filled with starch. (Greatly magnified.)

1 The markings will be seen more distinctly if care is taken not to admit
too much light to the object. Rotate the diaphragm beneath the stage of the
microscope, or otherwise regulate the supply of light, until the opening is
found which gives the best effect.

20 FOUNDATIONS OF BOTANY

Examine again and note the blue coloration of the starch grains and
the unstained or yellow appearance of other substances in the field.
Cut very thin slices from beans, peas, or kernels of corn ; mount in
water, stain as above directed, and draw as seen under the microscope.
Compare with Figs. 7 and S.1 Note the fact that the starch is not
packed away in the seeds in bulk, but that it is enclosed in little
chambers or cells.

24, Plant-Cells. — Almost all the parts of the higher
plants are built up of little separate portions called cells.
\/The cell is the unit of plant-structure, and bears some-
thing the same relation to the plant of which it is a part
that one cell of a honeycomb does to the whole comb.
But this comparison is not a perfect one, for neither the
waxen wall of the honeycomb-cell nor the honey within it
is alive, while every plant-cell is or has been alive. And
even the largest ordinary honeycomb consists of only a
few hundred cells, while a large tree is made up of very
many millions of cells. The student must not conceive
of the cell as merely a, little chamber or enclosure. The
living, more or less liquid, or mucilage-like, or jelly-like
substance known as protoplasm, which forms a large portion
of the bulk of living and growing cells, is the all-important
part of such a cell. Professor Huxley has well called
this substance "the physical basis of life." Cells are of
all shapes and sizes, from little spheres a ten-thousandth
of an inch or less in diameter to slender tubes, such as
fibers of cotton, several inches long. To get an idea of
the appearance of some rather large cells, scrape a little
pulp from a ripe, mealy apple, and examine it first with

1 The differentiation between the starch grains, the other cell-contents,
and the cell-walls will appear better in the drawings if the starch grains are
sketched with blue ink.

STORAGE OF FOOD IN THE SEED 21

a strong magnifying glass, then with a moderate power of
the compound microscope. To see how dead, dry cell-
walls, with nothing inside them, look, examine (as before)
a very thin slice of elder pith, sunflower pith, or pith from
a dead cornstalk. Look also at the figures in Chapter VI
of this book. Notice that the simplest plants (Chapter XX)
consist of a single cell each. The study of the structure
of plants is the study of the forms which cells and groups
of cells assume, and the study of plant physiology is the
study of what cells and cell combinations do.

25. Absorption of Starch from the Cotyledons. — Examine with
the microscope, using a medium power, soaked beans and the cotyle-
dons from seedlings that have been growing for three or four weeks.
Stain the sections with iodine solution, and notice how completely
the clusters of starch grains that filled most of the cells of the un-
sprouted cotyledons have disappeared from the shriveled cotyledons
of the seedlings. A few grains may be left, but they have lost their
sharpness of outline.

26. Oil. — The presence of oil in any considerable
quantity in seeds is not as general as is the presence of
starch, though in many common seeds there is a good
deal of it.

Sometimes the oil is sufficiently abundant to make it
worth while to extract it by pressure, as is done with flax-
seed, cotton-seed, the seeds of some plants of the cress
family, the " castor bean," and other seeds.

27. Dissolving Oil from Ground Seeds. — It is not possi-
ble easily to show a class how oil is extracted from seeds
by pressure ; but there are several liquids which readily
dissolve oils and yet have no effect on starch and most of
the other constituents of seeds.

22 FOUNDATIONS OF BOTANY

EXPERIMENT IX

Extraction of Oil by Ether or Benzine. — To a few ounces of
ground flaxseed add an equal volume of ether or benzine. Let it
stand ten or fifteen minutes and then filter. Let the liquid stand in
a saucer or evaporating dish in a good draught till it has lost the
odor of the ether or benzine.

Describe the oil which you have obtained.

Of what use would it have been to the plant?

If the student wishes to do this experiment at home for himself,
he should bear in mind the following :

Caution. — Never handle benzine or ether near a flame or stove.

A much simpler experiment to find oil in seeds may readily be
performed by the pupil at home. Put the material to be studied, e.g.,
flaxseed meal, corn meal, wheat flour, cotton-seed meal, buckwheat
flour, oatmeal, and so on, upon little labeled pieces of white paper,
one kind of flour or meal on each bit of paper. Place all the papers,
with their contents, on a perfectly clean plate, free from cracks, or
on a clean sheet of iron, and put this in an oven hot enough nearly
(but not quite) to scorch the paper. After half an hour remove the
plate from the oven, shake off the flour or meal from each paper, and
note the results, a more or less distinct grease spot showing the
presence of oil, or the absence of any stain that there was little or
no oil in the seed examined.

28. Albuminous Substances. — Albuminous substances
or proteids occur in all seeds, though often only in small
quantities. They have nearly the same chemical compo-
sition as white of egg and the curd of milk among animal
substances, and are essential to the plant, since the living
and growing parts of all plants contain large quantities of
proteid material.

Sometimes the albuminous constituents of the seed occur
in more or less regular grains (Fig. 8, at Kl) .

But much of the proteid material of seeds is not in any

STORAGE OF FOOD IN THE SEED 23

form in which it can be recognized under the microscope.
One test for its presence is the peculiar smell which it
produces in burning. Hair, wool, feathers, leather, and
lean meat all produce a well-known sickening smell when
scorched or burned, and the similarity of the proteid mate-
rial in such seeds as the bean and pea to these substances
is shown by the fact that scorching beans and similar
seeds give off the familiar smell of burnt feathers.

29. Chemical Tests for Proteids. — All proteids (and
very few other substances) are turned yellow by nitric
acid, and this yellow color becomes deeper or even orange
when the yellowish substance is moistened with ammonia.
They are also turned yellow by iodine solution. Most
proteids are turned more or less red by the solution of
nitrate of mercury known as Millon's reagent.1

EXPERIMENT X

Detection of Proteids in Seeds. — Extract the germs from some
soaked kernels of corn and bruise them; soak some wheat-germ meal
for a few hours in warm water, or wash the starch out of wheat-
flour dough ; reserving the latter for use, place it in a white saucer or
porcelain evaporating dish, and moisten well with Millon's reagent
or with nitric acid ; examine after fifteen minutes.

30. The Brazil-Nut as a Typical Oily Seed. — Not many
familiar seeds are as oily as the Brazil-nut. Its large size
makes it convenient for examination, and the fact that this
nut is good for human food makes it the more interesting
to investigate the kinds of plant-food which it contains.

1 See Handbook.

24 FOUNDATIONS OF BOTANY

EXPERIMENT XI1

Testing Brazil-Nuts for Plant-Foods. — Crack fifteen or twenty
Brazil-nuts, peel off the brown coating from the kernel of each, and
then grind the kernels to a pulp in a mortar. Shake up this pulp
with ether, pour upon a paper filter, and wash with ether until the
washings when evaporated are nearly free from oil. The funnel
containing the filter should be kept covered as much as possible
until the washing is finished. Evaporate the filtrate to procure the
oil, which may afterwards be kept in a glass-stoppered bottle. Dry
the powder which remains on the filter and keep it in a wide-
mouthed bottle. Test portions of this powder for proteids and for
starch. Explain the results obtained.

31. Other Constituents of Seeds. — Besides the substances
above suggested, others occur in different seeds. Some
of these are of use in feeding the seedling, others are of
value in protecting the seed itself from being eaten by
animals or in rendering it less liable to decay. In such
seeds as that of the nutmeg, the essential oil which gives
it its characteristic flavor probably makes it unpalatable
to animals and at the same time preserves it from decay.

Date seeds are so hard and tough that they cannot be
eaten and do not readily decay. Lemon, orange, horse-
chestnut and buckeye seeds are- too bitter to be eaten, and
the seeds of the apple, cherry, peach, and plum are some-
what bitter.

The seeds of larkspur, thorn-apple,1 croton, the castor-
oil plant, nux vomica, and many other kinds of plants
contain active poisons.

1 Datura, commonly called " Jimpson weed."

CHAPTER III

MOVEMENTS, DEVELOPMENT, AND MORPHOLOGY OF
THE SEEDLING

32, How the Seedling breaks Ground. — As the student
has already learned by his own observations, the seedling
does not always push its way straight out of the ground.
Corn, like all the other grains and grasses, it is true, sends
a tightly rolled, pointed leaf vertically upward into the
air. But the other seedlings examined usually will not
be found to do anything of the sort. The squash seedling
is a good one in which to study what may
be called the arched hypocotyl
type of germination. If the
seed when planted is laid hori-

A B c D E

FIG. 9. — Successive Stages in the Life History of the Squash Seedling.

GG, the surface of the ground ; r, primary root ; r', secondary root ; c, hypocotyl ;
a, arch of hypocotyl ; co, cotyledons.

zontally on one of its broad surfaces, it usually goes through
some such changes of position as are shown in Fig. 9.

26 FOUNDATIONS OF BOTANY

The seed is gradually tilted until, at the time of their
emergence from the ground (at (7), the cotyledons are
almost vertical. The only part above the ground-line 6r, 6r,
at this period, is the arched hypocotyl. Once out of ground,
the cotyledons soon rise, until (at E) they are again ver-
tical, but with the other end up from that which stood
highest in C. Then the two cotyledons separate until
they once more lie horizontal, pointing away from each
other.

Can you suggest any advantage which the plant derives
from having the cotyledons dragged out of the ground
rather than having them pushed out, tips first ?

33. Cause of the Arch. — It is evident that a flexible
object like the hypocotyl, when pushed upward through the
earth, might easily be bent into an arch or loop. Whether
the shape which the hypocotyl assumes is wholly caused
by the resistance of the soil can best be ascertained by
an experiment.

EXPERIMENT XII

Is the Arch of the Hypocotyl due to the Pressure of the Soil on the
Rising Cotyledons ? — Sprout some squash seeds on wet paper under
a bell-glass, and when the root is an inch or more long, hang several
of the seedlings, roots down, in little stirrups made of soft twine,
attached by beeswax and rosin mixture to the inside of the upper
part of a bell-glass. Put the bell-glass on a large plate or a sheet of
glass on which lies wet paper to keep the air moist. Note whether
the seedlings form hypocotyl arches at all and, if so, whether the
arch is more or less perfect than that formed by seedlings growing
in earth, sand, or sawdust.

34. What pushes the Cotyledons up? — A very little
study of any set of squash seedlings, or even of Fig. 9, is

MORPHOLOGY OF THE SEEDLING 27

sufficient to show that the portion of the plant where
roots and hypocotyl are joined neither rises nor sinks, but
that the plant grows both ways from this part (a little
above rr in Fig. 9, A and B). It is evident that as soon as
the hypocotyl begins to lengthen much it must do one of
two things : either push the cotyledons out into the air or
else force the root down into the ground as one might
push a stake down. What changes does the plantlet
undergo, in passing from the stage shown at A to that
of B and of 6y, making it harder and harder for the root
to be thrust downward?

35. Use of the Peg. — Squash seedlings usually (though
not always) form a sort of knob on the hypocotyl. This is
known as the peg. Study a good many seedlings and try
to find out what the lengthening of the hypocotyl, between
the peg and the bases of the cotyledons, does for the little
plant. Set a lot of squash seeds, hilum down, in moist
sand or sawdust and see whether the peg is more or less
developed than in seeds sprouted lying on their sides, and
whether the cotyledons in the case of the vertically planted
seeds usually come out of the ground in the same condi-
tion as do those shown in Fig. 9.

36. Discrimination between Root and Hypocotyl. — It is
not always easy to decide by their appearance and be-
havior what part of the seedling is root and what part is
hypocotyl. In a seedling visibly beginning to germinate,
the sprout, as it is commonly called, which projects from
the seed might be either root or hypocotyl or might consist
of both together, so far as its appearance is concerned. A
microscopic study of the cross-section of a root, compared
with one of the hypocotyl, would show decided differences

28 FOUNDATIONS OF BOTANY

of structure between the two. Their mode of growth is
also different, as the pupil may infer after he has tried
Exp. XIV.

37. Discrimination by Staining. — For some reason, per-
haps because the skin or epidermis of the young root is
not so water-proof as that of the stem, the former stains
more easily than the latter does.

EXPERIMENT XIII

The Permanganate Test. — Make a solution of potassium perman-
ganate in water, by adding about four parts, by weight, of the crystal-
lized permanganate to 100 parts of water. Drop into the solution
seedlings, e.g., of all the kinds that have been so far studied, each in
its earliest stage of germination (that is, when the root or hypocotyl
has pushed out of the seed half an inch or less), and also at one or
two subsequent stages. After the seedlings have been in the solu-
tion from three to five minutes, or as soon as the roots are consider-
ably stained, pour off (and save) the solution and rinse the plants
with plenty of clear water. Sketch one specimen of each kind, col-
oring the brown-stained part, which is root, in some way so as to
distinguish it from the unstained hypocotyl. Note particularly how
much difference there is in the amount of lengthening in the several
kinds of hypocotyl examined. Decide whether the peg of the squash
seedling is an outgrowth of hypocotyl or of root.

38. Disposition made of the Cotyledons. — As soon as
the young plants of squash, bean, and pea have reached
a height of three or four inches above the ground it is
easy to recognize important differences in the way in
which they set out in life.

The cotyledons of the squash increase greatly in sur-
face, acquire a green color and a generally leaf-like appear-
ance, and, in fact, do the work of ordinary leaves. In

MORPHOLOGY OF THE SEEDLING 29

such a case as this the appropriateness of the name seed-
leaf is evident enough, — one recognizes at sight the fact
that the cotyledons are actually the plant's first leaves.
In the bean the leaf-like nature of the cotyledons is not
so clear. They rise out of the ground like the squash
cotyledons, but then gradually shrivel away, though they
may first turn green and somewhat leaf-like for a time.

In the pea (as in the acorn, the horse-chestnut, and
many other seeds) we have quite another plan, the under-
ground type of germination. Here the thick cotyledons
no longer rise above ground at all, because they are so
gorged with food that they could never become leaves ;
but the young stem pushes rapidly up from the surface
of the soil.

The development of the plumule seems to depend some-
what on that of the cotyledons. The squash seed has
cotyledons which are not too thick to become useful leaves,
and so the plant is in no special haste to get ready any
other leaves. The plumule, therefore, cannot be found
with the magnifying glass in the unsprouted seed, and is
almost microscopic in size at the time when the hypocotyl
begins to show outside of the seed-coats.

In the bean and pea, on the other hand, since the cotyle-
dons cannot serve as foliage leaves, the later leaves must
be pushed forward rapidly. In the bean the first pair are
already well formed in the seed. In the pea they cannot
be clearly made out, since the young plant forms several
scales on its stem before it produces any full-sized leaves^
and the embryo contains only hypocotyl, cotyledons, and a
sort of knobbed plumule, well developed in point of size,
representing the lower scaly part of the stem.

30 FOUNDATIONS OF BOTANY

39. Root, Stem, and Leaf. — By the time the seedling is
well out of the ground it, in most cases, possesses the three
kinds of vegetative organs, or parts essential to growth, of
ordinary flowering plants, i.e., the root, stem, and leaf, or,
as they are sometimes classified, root and shoot. All of
these organs may multiply and increase in size as the
plant grows older, and their mature structure will be
studied in later chapters, but some facts concerning them
can best be learned by watching their growth from the
outset.

40. Young Roots grown for Examination. — Roots grow-
ing in sand or ordinary soil cling to its particles so tena-
ciously that they cannot easily be studied, and those grown
in water have not quite the same form as soil-roots. Roots
grown in damp air are best adapted for careful study.

41. Elongation of the Root. — We know that the roots
of seedlings grow pretty rapidly from the fact that each
day finds them reaching visibly farther down into the
water or other medium in which they are planted. A
sprouted Windsor bean in a vertical thistle-tube will send
its root downward fast enough so that ten minutes' watch-
ing through the microscope will suffice to show growth.
To find out just where the growth goes on requires a
special experiment.

EXPERIMENT XIV

In what Portions of the Root does its Increase in Length take Place ?
— Sprout some peas on moist blotting paper in a loosely covered tum-
bler. When the roots are one and a half inches or more long, mark
them along the whole length with little dots made with a bristle
dipped in water-proof India ink, or a fine inked thread stretched on
a little bow of whalebone or brass wire.

MORPHOLOGY OF THE SEEDLING 31

Transfer the plants to moist blotting paper under a bell-glass or
an inverted battery jar and examine the roots at the end of twenty-
four hours to see along what portions their length has increased ;
continue observations on them for several days.

42. Root-Hairs. — Barley, oats, wheat, red clover, or
buckwheat seeds soaked and then sprouted on moist
blotting paper afford convenient' material for studying
root-hairs. The seeds may be kept covered with a watch-,
glass or a clock-glass while sprouting. After they have
begun to germinate well, care must be taken not to
have them kept in too moist an atmosphere, or very few
root-hairs will be formed. Examine with the magni-
fying glass those parts of the root which have these
appendages.

Try to find out whether all the portions of the root are
equally covered with hairs and, if not, where they are
most abundant. (See also Sect. 53.)

The root-hairs in plants growing under ordinary condi-
tions are surrounded by the moist soil and wrap them-
selves around microscopical particles of earth (Fig. 11).
Thus they are able rapidly to absorb through their thin
walls the soil-water, with whatever mineral substances it
has dissolved in it.

43. The Young Stem. — The hypocotyl, or portion of
the stem which lies below the cotyledons, is the earliest
formed portion of the stem. Sometimes this lengthens but
little ; often, however, as the student knows from his own
observations, the hypocotyl lengthens enough to raise the
cotyledons well above ground, as in Fig. 10.

The later portions of the stem are considered to be
divided into successive nodes, — places at which a leaf (or

FOUNDATIONS OF BOTANY

a scale which represents a leaf) appears; and internodes, —
portions between the leaves./

The student should watch the growth of a seedling
bean or pea and ascertain by actual measurements whether
the internodes lengthen after they have once been formed,
and if so, for how long a time the increase continues.

FIG. 10. FIG. 11.

FIG. 10. — A Turnip Seedling, with the Cotyledons developed into Temporary Leaves.
h, root-hairs from the primary root ; bf bare portion of the root, on which no
hairs have as yet been produced.

FIG. 11. —Cross-Section of a Koot, a good deal magnified, showing root-hairs attached
to particles of soil, and sometimes enwrapping these particles.

44, The First Leaves. — The cotyledons are, as already
explained, the first leaves which the seedling possesses, —
even if a plumule is found well developed in the seed, it
was formed after the cotyledons. In those plants which
have so much food stored in the cotyledons as to render
these unfit ever to become useful foliage leaves, there is
little or nothing in the color, shape, or general appearance

MORPHOLOGY OF THE SEEDLING 33

of the cotyledon to make one think it really a leaf, and it
is only by studying many cases that the botanist is enabled
to class all cotyledons as leaves in their nature, even if they
are quite unable to do the ordinary work of leaves. The
study of the various forms which the parts or organs of a
plant may assume is called morphology ; it traces the rela-
tionship of parts which are really akin to each other,
though dissimilar in appearance and -often in function.
In seeds which have endosperm, or food stored outside of
the embryo, the cotyledons usually become green and
leaf-like, as they do, for example, in the four-o'clock, the
morning-glory, and the buckwheat ; but in the seeds of
the grains (which contain endosperm) a large portion of
the single cotyledon remains throughout as a thickish
mass buried in the seed. In a few cases, as in the pea,
there are scales instead of true leaves formed on the first
nodes above the cotyledons, and it is only at about the
third node above that leaves of the ordinary co

kind appear. In the bean and some other
plants which in general bear one leaf at a
node along the stem, there is a pair produced
at the first node above the cotyledons, and
the leaves of this pair differ in shape from
those which arise from the succeeding por-
tions of the stem.

45. Classification of Plants by the Number
of their Cotyledons. — In the pine family the FlG 12 ^
germinating seed often displays more than minating pine,
two cotyledons, as shown in Fig. 12; in the co> cotyledons-
majority of common flowering plants the seed con-
tains two cotyledons, while in the lilies, the rushes, the

FOUNDATIONS OF BOTANY

sedges, the grasses, and some other plants, there is but one
cotyledon. Upon these facts is based the division of most
flowering plants into two great groups : the dicotyledonous
plants, which have two seed-leaves, and the monocotyledon-
ous plants, which have one seed-leaf. Other important
differences nearly always accompany the difference in
number of cotyledons, as will be seen later.

46. Tabular Review of Experiments. — Make out a
table containing a very brief summary of the experiments
thus far performed, as follows :

NUMBER
OF

EXPERIMENT

OBJECT

SOUGHT

MATERIALS

AND

APPARATUS

OPERA-
TIONS
PERFORMED

RESULTS

INFERENCES

47. Review Sketches. — Make out a comparison of the
early life histories of all the other seedlings studied, by
arranging in parallel columns a series of drawings of each,

MORPHOLOGY OF THE SEEDLING

like those of Fig. 9, but in vertical series, the youngest
of each at the top, thus :

BEAN

PEA

CORN

FIRST STAGE

SECOND STAGE

THIRD STAGE

FOURTH STAGE

FIFTH STAGE

ETC.

CHAPTER IV
• ROOTS 1

48. Origin of Roots. — The primary root originates from
the lower end of the hypocotyl, as the student learned
from his own observations on sprouting seeds. The
branches of the primary root are called secondary roots,
and the branches of these are known as tertiary roots.
Those roots which occur on the stem or in other unusual
places are known as adventitious roots. The roots which
form so readily on cuttings of willow, southernwood,
tropseolum, French marigold, geranium (pelargonium),
tradescantia, and many other plants, when placed in damp
earth or water, are adventitious.

49. Aerial Roots. —While the roots of most familiar
plants grow in the earth and are known as soil-roots, there
are others which are formed in the air, called aerial roots.
They serve various purposes : in some tropical air-plants
(Fig. 13) they serve to fasten the plant to the tree on
which it establishes itself, as well as to take in water which
drips from branches and trunks above them, so that these
plants require no soil and grow in mid-air suspended from
trees, which serve them merely as supports ; 2 many such

1 To the plant the root is more important than the stem. The author has,
however, treated the structure of the latter more fully than that of the root,
mainly because the tissues are more varied in the stem and a moderate knowl-
edge of the more complex anatomy of the stem will serve every purpose.

2 If it can be conveniently managed, the class will find it highly interesting
and profitable to visit any greenhouse of considerable size, in which the aerial
roots of orchids and aroids may be examined.

ROOTS

air-plants are grown in greenhouses. In such plants as the
ivy (Fig. 15) the aerial roots (which are also adventitious)
hold the plant to the wall or other surface up which it climbs.
In the Indian corn (Fig. 14) roots are sent out from
nodes at some dis-

tance above the
ground and finally
descend until they
enter the ground.
They serve both to
anchor the cornstalk
so as to enable it to
resist the wind and
to supply additional
water to the plant.1
They often produce
no rootlets until they (/
reach the ground.

50. Water-Roots. — Many
plants, such as the willow,
readily adapt their roots to j
live either in earth or in water,
and some, like the little float-
ing duckweed, regularly pro-
duce roots which are adapted to live in water
only. These water-roots often show large and
distinct sheaths on the ends of the roots, as, for instance,
in the so-called water-hyacinth. This plant is especially
interesting for laboratory cultivation from the fact that

FlG. 13. — Aerial
Boots of an Orchid.

1 Specimens of the lower part of the cornstalk, with ordinary roots and
aerial roots, should be dried and kept for class study.

FOUNDATIONS OF BOTANY

FlG. 14.— Lower Part of Stem and Knots of Indian Corn, showing Aerial
Roots ( " Brace-Roots " ).

a, c, internodes of the stem ; b, d, e,f, nodes of various age bearing roots. Most of
these started as aerial roots, but all except those from b have now reached the earth.

ROOTS

it may readily be transferred to moderately damp soil,
and that the whole plant presents curious modifications
when made to grow in earth instead of water.

51. Parasitic Roots.1 — The dodder, the mistletoe, and a
good many other parasites, live upon nourishment which
they steal from other plants, called hosts. The parasitic

FIG. 15. — Aerial Adventitious Roots of the Ivy.

roots, or haustoria, form the most intimate connections
with the interior portions of the stem or the root, as the
case may be, of the host-plant on which the parasite
fastens itself.

In the dodder, as is shown in Fig. 16, it is most inter-
esting to notice how admirably the seedling parasite is
adapted to the conditions under which it is to live. Rooted

1 See Kerner and Oliver's Natural History of Plants, Vol. I, pp. 171-213,

FOUNDATIONS OF BOTANY

at first in the ground, it develops a slender, leafless stem,
which, leaning this way and that, no sooner comes into

ABC

FIG. 16. — Dodder, growing upon a Golden-Rod Stem.

s, seedling dodder plants, growing in earth ; h, stem of host ; r, haustoria or
parasitic roots of dodder ; Z, scale-like leaves. A, magnified section of a por-
tion of willow stem, showing penetration of haustoria.

permanent contact with a congenial host than it produces
haustoria at many points, gives up further growth in its

ROOTS

soil-roots, and grows rapidly on the strength of the sup-
plies of ready-made sap which it obtains from the host.

52. Forms of Roots The primary root is that which

proceeds like a downward prolongation directly from the
lower end of the hypocotyl. In many cases the mature root-
system of the plant contains one main root much larger
than any of its branches. This is called a taproot (Fig. 17).

Such a root, if much thickened, would assume the form

FIG. 17. — A Taproot. FIG. 18. — Fibrous Roots. FIG. 19. — Fascicled Roots.

shown in the carrot, parsnip, beet, turnip, salsify, or radish,
and is called a fleshy root. Some plants produce multiple
primary roots, that is, a cluster proceeding from the lower
end of the hypocotyl at the outset. If such roots become
thickened, like those of the sweet potato and the dahlia
(Fig. 19), they are known as fascicled roots.

Roots of grasses, etc., are thread-like, and known as
fibrous roots (Fig. 18).

53. General Structure of Roots The structure of the

very young root can be partially made out by examining

FOUNDATIONS OF BOTANY

the entire root with a moderate magnifying power, since
the whole is sufficiently translucent to allow the interior
as well as the exterior portion to be studied while the root
is still alive and growing.

Place some vigorous cuttings of tradescantia or Zebrina, which'
can usually be obtained of a gardener or florist, in a beaker or jar of

water.1 The jar should
be as thin and trans-
parent as possible, and
it is well to get a flat-
sided rather than a
cylindrical one. Leave
the jar of cuttings in
a sunny, warm place.
As soon as roots have
developed at the nodes
and reached the length
of three-quarters of an
inch or more, arrange
a microscope in a hori-
zontal position (see
Handbook), and exam-
ine the tip and adjacent
portion of one of the
young roots with a
power of from twelve
to twent diameters.

FIG. 20. — Lengthwise Section (somewhat diagram-
matic) through Root-Tip of Indian Corn, x about 130.

W, root-cap ; i, younger part of cap ; z, dead cells sepa-
rating from cap ; s, growing point ; o, epiderm's ; p',
intermediate layer between epidermis and central
cylinder; p, central cylinder; d, layer from which
the root-cap originates.

Note:

(a) The root-cap,

of loosely

attached cells.

(&) The central

cylinder.

1 If the tradescantia or Zebrina cannot be obtained, roots of seedlings of
oats, wheat, or barley, or of red-clover seedlings raised in a large covered cell
on a microscope slide, may be used.

ROOTS 43

(W) The root-hairs, which cover some parts of the outer layer of
the cortical portion very thickly. Observe particularly
how far toward the tip of the root the root-hairs extend,
and where the youngest ones are found.

Make a drawing to illustrate all the points above suggested
(a, 6, c, rf). Compare your drawing with Fig. 20. Make a careful
study of longitudinal sections through the centers of the tips of very-
young roots of the hyacinth or the Chinese sacred lily. Sketch
one section and compare the sketch with Fig. 20.

Make a study of the roots of any of the common duckweeds,
growing in nutrient solution in a jar of water under a bell-glass, and
note the curious root-pockets which here take the place of root-caps.

54. Details of Root-Structure. — The plan on which the
young root is built has been outlined in Sect. 53. A few
further particulars are necessary to an understanding of
how the root does its work. On examining Fig. 21 the
cylinders of which the root is made up are easily dis-
tinguished, and the main constituent parts of each jean be
made out without much trouble. The epidermis-cells are
seen to be somewhat brick-shaped, many of them provided
with extensions into root-hairs. Inside the epidermis lie
several layers of rather globular, thin-walled cells, and
inside these a boundary layer between the cortical or bark
portion of the root and the central cylinder. This latter
region is especially marked by the presence of certain
groups of cells, shown at w and d and at £>, the two
former serving as channels for air and water, the latter
(and w also) giving toughness to the root.

Roots of shrubs and trees more than a year old will
be found to have increased in thickness by the process

FOUNDATIONS OF BOTANY

described in Sect. 106, and a section may look quite unlike
the young root-section shown in Fig. 21.

55, Examination of the Root of a Shrub or Tree. — Cut thin
transverse sections of large and small roots of any hardwood tree l
and examine them first with a low power of the microscope, as a
two-inch objective, to get the general disposition of the parts, then

with a higher power,
as the half-inch or
quarter-inch, for de-
tails. With the low
power, note :

(a) The brown
layer of outer bark.

(&) The paler layer
within this.

The distinction be-
tween (b) and (c) is
more evident when
the section has been
exposed to the air for
a few minutes and

h, root-hairs with adhering hits of sand ; e, epidermis ; changed somewhat in

color. It is a good
plan to look with the
low power first at a thick section, viewed as an opaque object, and
then at a very thin one mounted in water or glycerine, and viewed as
a transparent object.

Observe the cut-off ends of the ducts, or vessels, which serve as
passages for air and water to travel through ; these appear as holes in
the section, and are much more abundant relatively in the young

1 Young suckers of cherry, apple, etc., which may be pulled up by the
roots, will afford excellent material.

FIG. 21. —Much Magnified Cross-Section of a
Very Young Dicotyledonous Root.

s, thin-walled, nearly globular cells of hark ; b, hard
bast ; c, cambium ; w, wood-cells ; d, ducts.

ROOTS 45

than in the older and larger portions of the root. Sketch one section
of each kind.

Examine with a higher power (100 to 200 diameters), and note the
ends of the thick-walled wood-cells. Compare these with Fig. 72.

Notice the many thinner-walled cells composing stripes radiating
away from the center of the root. These bands are the medullary
rays, whose mode of origin is shown in Fig. 68. Moisten some of
the sections with iodine solution,1 and note where the blue color
shows the presence of starch. Split some portions of the root through
the middle, cut thin sections from the split surface, and examine with
the high power some unstained and some stained with iodine.

Notice the appearance of the wood-cells and the ducts as seen in
these sections, and compare with Fig. 58. 2

56, Structure and Contents of a Fleshy Root. — In some
fleshy roots, such as the beet, the morphology of the parts
is rather puzzling, since they form man}*- layers of tissue
in a single season, showing on the cross-section of the root
a series of layers which look a little like the annual rings
of trees.

The structure of the turnip, radish, carrot, and parsnip
is simpler.

Cut a parsnip across a good deal below the middle, and stand the
cut end in eosin solution for twTenty-four hours.

Then examine by slicing off successive portions from the upper
end. Sketch some of the sections thus made. Cut one parsnip
lengthwise and sketch the section obtained. In what portion of the
root did the colored liquid rise most readily ? The ring of red marks
the boundary between the cortical portion and the central cylinder.
To which does the main bulk of the parsnip belong? Cut thin
transverse sections from an ink-stained parsnip and notice how the
medullary rays run out into the cortical portion, and in those sections

1 If the roots are in their winter condition.

2 The examination of the minute structure of the root is purposely made
very hasty, since the detailed study of the structural elements can be made to
better advantage in the stem.

46 FOUNDATIONS OF BOTANY

that show it, find out where the secondary roots arise. If possible,
peel off the cortical portion from one stained root and leave the cen-
tral cylinder with the secondaiy roots attached. Stain one section
with iodine, and sketch it. Where is the starch of this root mainly
stored?

Test some bits of parsnip for proteids, by boiling them for a
minute or two with strong nitric acid.

What kind of plant-food does the taste of cooked parsnips show
them to contain ? [On no account taste the bits which have been
boiled in the 'poisonous nitric acid.]

57. Storage in Other Roots. — The parsnip is by no
means a remarkable plant in its capacity for root-storage.
The roots of the yam and the sweet potato contain a good
deal of sugar and much more starch than is found, in the
parsnip. Beet-roots contain so much sugar that a large
part of the sugar supply of Europe and an increasing
portion of our own supply is obtained from them. Often-
times the bulk of a fleshy root is exceedingly large as
compared with that of the parts of the plant above
ground.

The South African plant (Harpagophytum, Chapter
XXIV) is a good example of this, and another instance
is that of a plant,1 related to the morning-glory and the
sweet potato, found in the southeastern United States,
which has a root of forty or fifty pounds weight.

Not infrequently roots have a bitter or nauseous taste,
as in the case of the chicory, the dandelion, and the
rhubarb, and a good many, like the monkshood, the yellow
jasmine, and the pinkroot, are poisonous. Can you give
any reason why the plant may be benefited by the disgust-
ing taste or poisonous nature of its roots ? \
1 Ipom&a Jalapa,

ROOTS

58. Use of the Food stored in Fleshy Roots. — The
parsnip, beet, carrot, and turnip are biennial plants ; that
is, they do not produce seed until the second summer or
fall after they are planted.

The first season's work consists mainly in producing the
food which is stored in the roots. To such storage is
due their characteristic fleshy appear-
ance. If this root is planted in the
following spring, it feeds the rapidly
growing stem which proceeds from the
bud at its summit, and an abundant
crop of flowers and seed soon follows ;
while the root, if examined in late sum-
mer, will be found to be withered, with
its store of reserve material quite ex-
hausted.

The roots of the rhubarb (Fig. 22),
the sweet potato, and of a multitude of
other perennials, or plants which live
for many years, contain much stored
plant-food. Many such plants die to
the ground at the beginning of winter,
and in spring make a rapid growth from the materials laid
up in the roots.

59. Extent of the Root-System. — The total length of
the roots of ordinary plants is much greater than is usually
supposed. They are so closely packed in the earth that
only a few of the roots are seen at a time during the
process of transplanting, and when a plant is pulled or dug
up in the ordinary way, a large part of the whole mass of
roots is broken off and left behind. A few plants have

FIG. 22. — Fleshy Koots

of Garden Rhubarb.

(About one-fifteenth

natural size.)

48 FOUNDATIONS OF BOTANY

been carefully studied to ascertain the total weight and
length of the roots. Those of winter wheat have been
found to extend to a depth of seven feet. By weighing
the whole root-system of a plant and then weighing a
known length of a root of average diameter, the total
length of the roots may be estimated. In this way the
roots of an oat plant have been calculated to measure
about 154 feet; that is, all the roots, if cut off and strung
together end to end, would reach that distance.

Single roots of large trees often extend horizontally to
great distances, but it is not often possible readily to trace
the entire depth to which they extend. One of the most
notable examples of an enormously developed root-system
is found in the mesquite of the far Southwest and Mexico.
When this plant grows as a shrub, reaching the height,
even in old age, of only two or three feet, it is because the
water supply in the soil is very scanty. In such cases
the roots extend down to a depth of sixty feet or more,
until they reach water, and the Mexican farmers in dig-
ging wells follow these roots as guides. Where water is
more plenty, the mesquite forms a good-sized tree, with
much less remarkably developed roots.

60. The Absorbing Surface of Roots. — Such aerial roots
as are shown in Fig. 13 are usually covered with a spongy
absorbent layer, by means of which they retain large
quantities of the water which trickles down them during
rain-storms. This water they afterwards gradually give
up to the plant. Most water-roots (not however those of
tradescantia) have no special arrangement for absorbing
water except through the general surface of their epidermis.
But some water-roots and most soil-roots take in water

ROOTS

mainly through the root-hairs. These are delicate, hair-
like outgrowths from the epidermis of the root. They
are, as seen in Fig. 11, thin-walled tubes, of nearly uniform
diameter, closed at the outer end and opening at the inner
end into the epidermis-cell from which they
spring. The relation of each hair to the
epidermis-cell is still better shown in Fig.
23, which represents a very young root-
hair and a considerably older one.

61. Absorption of Water by Roots. —
Many experiments on the
cultivation of corn, wheat,
oats, beans, peas, and other
familiar plants in water have
proved that some plants, at
any rate, can thrive very
well on ordinary lake, river,
or well water, together with
the food which they absorb
from the air (Chapter XII).
Just how much water some
kinds of plants give off (and
therefore absorb) per day
will be discussed when the
uses of the leaf are studied.
For the present it is suffi-
cient to state that even an
annual plant during its' lifetime absorbs through the roots
very many times its own weight of water. Grasses have been
known to take in their weight of water in every twenty-
four hours of warm, dry weather. This absorption takes

n---

FIG. 23.

A, a very young root-hair ; B, a much
older one (both greatly magnified).
e, cells of the epidermis of the root ;
n, nucleus ; s, watery cell-sap ; p,
thicker protoplasm, lining the cell-
wall.

50 FOUNDATIONS OF BOTANY

place mainly through the root-hairs, which the student has
examined as they occur in the seedling plant, and which
are found thickly clothing the younger and more rapidly
growing parts of the roots of mature plants. Some idea
of their abundance may be gathered from the fact that on
a rootlet of corn grown in a damp atmosphere, and about
one-seventeenth of an inch in diameter, 480 root-hairs have
been counted on each hundredth of an inch of root. The
walls of the root-hairs are extremely thin, and they have
no holes or pores visible under even the highest power
of the microscope, yet the water of the soil penetrates
very rapidly to the interior of the root-hairs. The
soil-water brings with it all the substances which it can
dissolve from the earth about the plant ; and the close-
ness with which the root-hairs cling to the particles of soil,
as shown in Figs. 11 and 21, must cause the water which
is absorbed to contain more foreign matter than under-
ground water in general does, particularly since the roots
give off enough weak acid from their surface to corrode
the surface of stones which they enfold or cover.

62. Osmosis. — The process by which two liquids sep-
arated by membranes pass through the latter and mingle,
as soil-water does with the liquid contents of root-hairs, is
called osmosis.

It is readily demonstrated by experiments with thin
animal or vegetable membranes.

EXPERIMENT XV

Osmosis as shown in an Egg. — Cement to the smaller end of an egg
a bit of glass tubing about six inches long and about three-sixteenths
of an inch inside diameter. Sealing-wax or a mixture of equal parts
of beeswax and resin melted together will serve for a cement.

ROOTS

Chip away part of the shell from the larger end of the egg, place
it in a wide-mouthed bottle or a small beaker full of water, as shown
in Fig. 24, then very cautiously pierce a* hole through the upper end
of the eggshell by pushing a knitting-needle or wire down through
the glass tube.

Watch the apparatus for some hours and note any change in the
contents of the tube.1 Explain.

The rise of liquid in the tube is evidently due to water making
its way through the thin membrane which lines the eggshell,
although this membrane contains no pores visible even under the
microscope.

EXPERIMENT XYI

Result of placing Sugar on a Begonia Leaf. — Place a little pow-
dered sugar on the upper surface of a thick begonia leaf under a small
bell-glass. Put another por-
tion of sugar or a bit of paper
alongside the leaf. Watch for
several days. Explain results.
The upper surface of this leaf
contains no pores, even of
microscopic size.

63. Inequality of Os-
motic Exchange. — The
nature of the two liquids
separated by any given
membrane determines in
which direction the
greater flow shall take
place.

If one of the liquids is
pure water and the other

FIG. 24. —Egg on Beaker of Water,
to show Osmosis.

1 Testing the contents of the beaker with nitrate of silver solution will
then show the presence of more common salt than is found in ordinary water.
Explain.

52 FOUNDATIONS OF BOTANY

is water containing solid substances dissolved in it, the
greater flow of liquid will be away from the pure water
into the solution, and the stronger or denser the latter, the
more unequal will be the flow. This principle is well illus-
trated by the egg-osmosis experiment. Another important
principle is that substances which readily crystallize and
are easily soluble, like salt or sugar, pass rapidly through
membranes, while jelly-like substances, like white of egg,
can hardly pass through them at all.

64. Study of Osmotic Action of Living Protoplasm;
Plasmolysis. — The obvious parts of most living and grow-
ing plant-cells are a cell-wall, which is a skin or enclosure
made of cellulose, and the living, active cell-contents or
protoplasm. Every one is familiar with cellulose in vari-
ous forms, one of the best examples being that afforded by
clean cotton. It is a tough, white or colorless substance,
chemically rather inactive. Protoplasm is a substance which
differs greatly in its appearance and properties under differ-
ent circumstances. It is of a very complex nature, so far as
its chemical composition is concerned, belonging to the group
of proteids and therefore containing not only the elements
carbon, hydrogen, and oxygen, common to most organic
substances, but nitrogen in addition. The protoplasm in
a living cell often consists of several kinds of material ; for
instance, a rather opaque portion called the nucleus, and a
more or less liquid portion lining the cell-walls and extend-
ing inward in strands to the nucleus (Fig. 126). Often, in
living and active cells, the spaces left between strands and
lining are filled with a watery liquid called the cell-sap.

The action of the protoplasm in controlling osmosis is
well shown by the process known as plasmolysis.

ROOTS 53

Put some living threads of pond-scum (Spirogyra) (Chapter XX)
into a 4 per cent solution of glycerine in water, a 16 per cent solution
of cane sugar, or (for quick results) a 2 per cent solution of common
salt.1 Any one of these solutions is much denser than the cell-sap
inside the cells of the pond-scum, and therefore the watery part of
the cell-contents will be drawn out of the interior of the cell and
the protoplasmic lining will collapse, receding from the cell-wall.
The cell-contents are then said to be plasmolyzed. Sketch several
cells in this condition. Remove the filaments of Spirogyra and
place them in fresh water. How do they now behave ? Explain.
Repeat the plasmolyzing operation with another set of cells which
have first been killed by soaking them for five minutes in a mixture
of equal quantities of acetic acid, three parts to 1000 of water, and
chromic acid, seven parts to 1000 of water. The pond-scum threads
before being transferred from the killing solution into the plas-
molyzing solution should be rinsed with a little clear water. Note
how the cells now behave. How is it shown that they have lost
their power of causing a liquid to be transferred mainly or wholly
in one direction? Why do frozen or boiled slices of a red beet
color water in which they are placed, while fresh slices do not?

65. Osmosis in Root-Hairs. — The soil-water (practically
identical with ordinary spring or well water) is separated
from the more or less sugary or mucilaginous sap inside
of the root-hairs only by their delicate cell-walls, lined
with a thin layer of protoplasm. This soil- water will pass
rapidly into the plant, while very little of the sap will
come out. The selective action, which causes the flow of
liquid through the root-hairs to be almost wholly inward,
is due to the living layer of protoplasm (Chapter XII),
which covers the inner surface of the cell-wall of the root-
hair. When the student has learned how active a sub-
stance protoplasm often shows itself to be, he will not be
astonished to find it behaving almost as though it were

1 This should be done as a demonstration by the teacher.

54 FOUNDATIONS OF BOTANY

possessed of intelligence and will. Plants of two different
species, both growing in the same soil, usually take from
it very various amounts or kinds of mineral matter. For
instance, barley plants in flower and red-clover plants in
flower contain about the same proportion of mineral mat-
ter (left as ashes after burning). But the clover contains
5| times as much lime as the barley, and the latter contains
about eighteen times as much silica as the clover. This
difference must be due to the selective action of the proto-
plasm in the absorbing cells of the roots. Traveling by
osmotic action from cell to cell, a current of water derived
from the root-hairs is forced up through the roots and into
the stem, just as the contents of the egg was forced up
into the tube shown in Fig. 24.

66. Root-Pressure. — The force with which the upward-
flowing current of water presses may be estimated by
attaching a mercury gauge to the root of a tree or the
stem of a small sapling. This is best done in early spring
after the thawing of the ground, but before the leaves
have appeared. The experiment may also be performed
indoors upon almost any plant with a moderately firm
stem, through which the water from the soil rises freely.
A dahlia plant or a tomato plant answers well, though the
root-pressure from one of these will not be nearly as great
as that from a larger shrub or a tree growing out of doors.
In Fig. 25 the apparatus is shown attached to the stem of
a dahlia. The difference of level of the mercury in the
bent tube serves to measure the root-pressure. For every
foot of difference in level there must be a pressure of
nearly six pounds per square inch on the stump at the
base of the tube T.1

1 See Handbook,

ROOTS

A black-birch root tested in this way at the end of
April has given a root-pressure of thiity-seven pounds to
the square inch. This would sustain a column of water
about eighty-six feet high.

67. Root-Absorption and
Temperature of Soil. — It
would not be remarkable if
the temperature of roots and
the earth about them had
something to do with the
rate at which they absorb
water, since this absorption
depends on the living proto-
plasm of the root-hairs (see
Sects. 64, 65). An experi-
ment will serve to throw
some light on this question.

EXPERIMENT XVII

Effect of Temperature on Absorp-
tion of Water by Roots. — Trans-

. ... i , /? T7, large tube fastened to the stump of

plant a tobacco seedling about four th d h]i t b bb t b

FIG. 25. — Apparatus to Measure
Root-Pressure.

rr, rubber stoppers; t, bent tube
containing mercury ; 1 1', upper and
lower level of mercury in T.

inches high into rich earth con-
tained in a narrow, tall beaker or
very large test-tube (not less than
1£ inch in diameter and six inches high). When the plant has begun
to grow again freely, in a warm, sunny room, insert a chemical ther-
mometer into the earth, best by making a hole with a sharp round
stick, pushed nearly to the bottom of the tube, and then putting the
thermometer in the place of the stick. Water the plant well, then
set the tube in a jar of pounded ice which reaches nearly to the
top of the tube. Note the temperature of the earth just before
placing it in the ice. Observe whether the leaves of the seedling wilt,

56 FOUNDATIONS OF BOTANY

and, if so, at what temperature the wilting begins. Finally, remove
the tube from the ice and place it in warm water (about 80°).
Observe the effect and note the temperature at which the plant,
if wilted, begins to revive. Find an average between the wilting
temperature and the reviving temperature. For what does this
average stand?

68, Movements of Young Roots. — The fact that roots
usually grow downward is so familiar that we do not
generally think of it as a thing that needs discussion or
explanation. Since they are pretty flexible, it may seem
as though young and slender roots merely hung down
by their own weight, like so many bits of wet cotton
twine. But a very little experimenting will answer the
question whether this is really the case.

EXPERIMENT XVIII

Do all Parts of the Root of the Windsor Bean Seedling bend down-
ward alike? — Fasten some sprouting Windsor beans with roots
about an inch in length to the edges of a disk of pine wood or
other soft wood in a soup-plate nearly full of water and cover them
with a low bell-jar. Pins run through the cotyledons, as in Fig. 26,
will hold the beans in place. When the roots have begun to point
downward strongly, turn most of the beans upside down and pin
them in the reversed position. If you choose, after a few days
reverse them again. Make sketches of the various forms that the
roots assume and discuss these.

EXPERIMENT XIX

Does the Windsor Bean Root-Tip press downward with a Force
greater than its Own Weight ? — Arrange a sprouted bean as shown
in Fig. 26, selecting one that has a root about twice as long as the
diameter of the bean and that has grown out horizontally, having
been sprouted on a sheet of wet blotting paper. The bean is pinned

ROOTS

FIG. 26. — A Sprouting "Windsor Bean pushing its
Root-Tip into Mercury.

s, seed ; r, root ; w, layer of water ; m, mercury.

to a cork that is fastened with beeswax and resin mixture to the
side of a little trough or pan of glass or glazed earthenware. The
pan is filled half an inch or more with mercury, and on top of
the mercury is a layer

of water. The whole f ^^ \

is closely covered by
a large tumbler or a
bell-glass. Allow the
apparatus to stand un-
til the root has forced
its way down into the
mercury. Then run a
slender needle into the
root where it enters
the mercury (to mark
the exact level), withdraw the root, and measure the length of
the part submerged in mercury. To see whether this part would
have stayed under by virtue of its own weight, cut it off and lay
it on the mercury. Push it under with a pair of steel forceps and
then let go of it. What does it do ?

69, Discussion of Exp. XIX. — By comparing the weights
of equal bulks of mercury and Windsor bean roots, it is
found that the mercury is about fourteen times as heavy
as the substance of the roots. Evidently, then, the sub-
merged part of the root must have been held under by
a force about fourteen times its own weight. Making fine
equidistant cross-marks with ink along the upper and the
lower surface of a root that is about to bend downward at
the tip, readily shows that those of the upper series soon
come to be farther apart, — in other words, that the root is
forced to bend downward by the more rapid growth of its
upper as compared with its under surface.

70. Geotropism. — The property which plants or their
organs manifest, of assuming a definite direction with

FOUNDATIONS OF BOTANY

reference to gravity,1 is called geotropism. When, as in
the case of the primary root, the effect of gravity is to
make the part if unobstructed turn or move downward,
we say that the geotropism is positive. If the tendency is
to produce upward movement, we say that the geotropism
is negative; if horizontal movement, that it is lateral. It
was stated in the preceding section that the direct cause
of the downward extension of roots is unequal growth.
We might easily suppose that this unequal growth is not
due to gravity, but to some other cause. To test this sup-
position, the simplest plan (if it could be carried out) would
be to remove the plants studied to some distant region
where gravity does not exist. This of course cannot be

done, but we can easily turn a
young seedling over and over
so that gravity will act on it
now in one direction, now in
another, and so leave no more
impression than if it did not act
at all (Exp. XX). Or we can
whirl a plant so fast that not
only is gravity done away with,
but another force is introduced
in its place. If a vertical wheel,
like a carriage wheel, were pro-
vided with a few loosely fitting
iron rings strung on the spokes,
when the wheel was revolved rapidly the rings would all
fly out to the rim of the wheel. So in Fig. 27 it will be

FIG. 27.— Sprouting Peas, on the Disk
of a rapidly Whirling Clinostat.

The youngest portions of the roots
all point directly away from the
axis about which they were re-
volved.

1 Gravity means the pull which the earth exerts upon all objects on or
near its surface.

ROOTS 59

noticed that the growing tips of the roots of the sprouting
peas point almost directly outward from the center of the
disk on which the seedlings are fastened. Explain the differ-
ence between this result and that obtained in Exp. XX.

S^ r*

EXPERIMENT XX

How do Primary Roots point when uninfluenced by Gravity ? Pin
some soaked Windsor beans to a large flat cork, cover them with
thoroughly moistened chopped peat-moss, and cover this with a thin
glass crystallizing dish. Set the cork on edge. Prepare another
cork in the same way, attach it to a clinostat, and keep it slowly
revolving in a vertical position for from three to five days. Com-
pare the directions taken by the roots on the stationary and on the
revolving cork.1

71. Direction taken by Secondary Roots. — As the stu-
dent has already noticed in the seedlings which he has
studied, the branches of the primary root usually make a
considerable angle with it (Fig. 2). Often they ran out
for long distances almost horizontally. This is especially
common in the roots of forest trees, above all in cone-
bearing trees, such as pines and hemlocks. This horizon-
tal or nearly horizontal position of large secondary roots
is the most advantageous arrangement to make them use-
ful in staying or guying the stem above, to prevent it from
being blown over by the wind.

72. Fitness of the Root for its Position and Work. — The
distribution of material in the woody roots of trees and
shrubs and their behavior in the soil show many adapta-
tions to the conditions by which the roots are surrounded.

1 See Ganong's Teaching Botanist, pp. 182-186, for complete directions.
The brief statement above given is abstracted from that of Professor Ganong.

FOUNDATIONS OF BOTANY

The growing tip of the root, as it pushes its way through
the soil, is exposed to bruises ; but these are largely warded
off by the root-cap. The tip also shows a remarkable
sensitiveness to contact with hard objects, so that when
touched by one it swerves aside and thus finds its way
downward by the easiest path. Roots with an unequal
water supply on either side grow toward the moister soil.
Roots are very tough, because they need to resist strong

FIG. 28. — Roots of a Western Hemlock exposed by having most of the Leaf -Mould
about them burned away by Forest Fires.

pulls, but not as stiff as stems and branches of the same
size, because they do not need to withstand sidewise pres-
sure, acting from one side only. The corky layer which
covers the outsides of -roots is remarkable for its power
of preventing evaporation. It must be of use in retaining
in the root the moisture which otherwise might be lost
on its way from the deeper rootlets (which are buried in
damp soil), through the upper portions of the root-system,
about which the soil is often very dry.

ROOTS 61

73, Propagation by Means of Roots. — Some familiar
plants, such as rose bushes, are usually grown from roots
or root-cuttings.

Bury a sweet potato or a dahlia root in damp sand, and watch
the development of sprouts from adventitious buds. One sweet
potato will produce several such crops of sprouts, and every sprout
may be made to grow into a new plant. It is in this way that the
crop is started wherever the sweet potato is grown for the market.

74, Tabular Review of Experiments.
[Continue the table begun at end of Chapter III.]

75, Review Summary of Roots.

Kinds of roots as regards origin . . . . .

Kinds as regards medium in which they grow .

Structure of root of a tree.

T mate rials.
Storage in roots *{ location.

louses.

f apparatus.

amount.

Absorption of water by roots ^

I proofs.

^causes.

f nature.
Movements of roots J causes.

I uses.

CHAPTER Y
STEMS

76. What the Stem is The work of taking in the raw

materials which the plant makes into its own food is done
mainly by the roots and the leaves. These raw materials
are taken from earth, from water, and from the air (see
Chapter XI). The stern is that part or organ of the plant
which serves to bring roots and leaves into communication
with each other. In most flowering plants the stem also
serves the important purpose of lifting the leaves up into
the sunlight, where alone they best can do their special
work.

The student has already, in Chapter III, learned some-
thing of the development of the stem and the seedling ;
he has now to study the external appearance and internal
structure of the mature stem. Much in regard to this
structure can conveniently be learned from the examina-
tion of twigs and branches of our common forest trees in
their winter condition.

77. The Horse-Chestnut Twig.1 — Procure a twig of horse-chest-
nut eighteen inches or more in length. Make a careful sketch of it,
trying to bring out the following points :

(1) The general character of the bark.

1 Where the buckeye is more readily obtained it will do very well. Hick-
ory twigs answer the same purpose, and the latter is a more typical form,
having alternate buds. The magnolia or the tulip tree will do. The student
should (sooner or later) examine at least one opposite- and one alternate-leaved
twig.

STEMS

(2) The large horseshoe-shaped scars and the number and posi-
tion of the dots on these scars. Compare a scar with the base of a
leaf-stalk furnished by the teacher.

(3) The ring of narrow scars around the stem in one or more
places,1 and the different appearance of the bark above and below
such a ring. Compare these scars with those left after removing the
scales of a terminal bud and then see Fig. 29, b sc.

(4) The buds at the upper margin of each leaf-
scar and the strong terminal bud at the end of the
twig.

(5) The flower-bud scar, a concave impression,
to be found in the angle produced by the forking
of two twigs, which form, with the branch from
which they spring, a Y-shaped figure (see Fig. 36).

(6) (On a branch larger than the twig handed
round for individual study) the place of origin of
the twigs on the branch ; — make a separate sketch
of this.

The portion of stem which originally bore any
pair of leaves is called a node, and the portions of
stem between nodes are called internodes.

Describe briefly in writing alongside the sketches
any observed facts which the drawings do not show.

If your twig was a crooked, rough-barked, and
slow-growing one, exchange it for a smooth, vig-
orous one, and note the differences. Or if you
sketched a quickly grown shoot, exchange for one
of the other kind.

Answer the following questions : 6 sc bud-scale scars.

(a) How many inches did your twig grow A11 above these
-, , , , scars is the growth
during the last summer? of the spri*g and

How many in the summer before? summer of the

How do you know?

How many years old is the whole twig given you ?

(b) How were the leaves arranged on the twig?

..b sc

Cherry, with Lat-
eral and Terminal
Buds in October.

same year.

1 A very vigorous shoot may not show any such ring.

64 FOUNDATIONS OF BOTANY

How many leaves were there ?
Were they all of the same size ?

(d) The dots on the leaf-scars mark the position of the bundles
of ducts and wood-cells which run from the wood of the branch
through the leaf -stalk up into the leaf.

78. Twig of Beech. — Sketch a vigorous young twig of beech (or
of hickory, magnolia, tulip tree) in its winter condition, noting par-
ticularly the respects in which it differs from the horse-chestnut.
Describe in writing any facts not shown in the sketch. Notice that
the buds are not opposite, nor is the next one above any given bud
found directly above it, but part way round the stem from the posi-
tion of the first one. Ascertain, by studying several twigs and
counting around, which bud is above the first and how many turns
round the stem are made in passing from the first to the one directly
above it.

Observe with especial care the difference between the beech and
the horse-chestnut in mode of branching, as shown in a large branch
provided for the study of this feature.

79. Relation of Leaf -Arrangement to Branching.1 — This
difference, referred to in Sect. 78, depends on the fact that
the leaves of the horse-chestnut were arranged in pairs, on
opposite sides of the stem, while those of the beech were
not in pairs. Since the buds are found at the upper edges
of the leaf-scars, and since most of the buds of the horse-
chestnut and the beech are leaf-buds and destined to form
branches, the mode of branching and ultimately the form

1 The teacher in the Eastern and Middle States will do well to make constant
use, in the study of branches and buds, of Miss Newell's Outlines of Lessons
in Botany, Part I. The student can observe for himself, with a little guid-
ance from the teacher, most of the points which Miss Newell suggests. If the
supply of material is abundant, the twigs employed in the lessons above
described need not be used further, but if material is scanty, the study of buds
may at once be taken up. (See also Bailey's Lessons with Plants, Part I.)

STEMS

of the tree must depend largely on the arrangement of

leaves along the stem.

80. Opposite Branching In trees the leaves and buds

of which are opposite, the tendency will be to form twigs

in four rows about at right angles

to each other along the sides of

the branch, as shown in Fig. 30.

This arrangement will not usu-
ally be perfectly carried out, since

some of the buds may never grow,
or some may
grow much
faster than
others and so
make the plan
of branching less
evident than it
would be if all
grew alike.

81. Alternate
Branching. — In

trees like the beech the twigs will be
found to be arranged in a more or less
regular spiral line about the branch.
This, which is known as the alternate
arrangement (Fig. 31), is more com-
monly met with in trees and shrubs
than the opposite arrangement. It ad-
mits of many varieties, since the spiral

may wind more or less rapidly round the stem. In the

apple, pear, cherry, poplar, oak, and walnut, one passes

FIG. 30. — Opposite Branching

in a very Young Sapling

of Ash.

FIG. 31. — Alternate
Branching in a very
Young Apple Tree.

FOUNDATIONS OF BOTANY

FIG. 32. — Excurrent Trunks of Big Trees
(Sequoias).

over five spaces before
coming to a leaf which
is over the first, and in
doing this it is necessary
to make two complete
turns round the stem
(Fig. 105).

82. Growth of the Ter-
minal Bud. — In some
trees the terminal bud
from the very outset
keeps the leading place,
and the result of this
mode of growth is to
produce a_slender, up-
right tree, with an excur-
rent trunk like that of
Fig. 32.

In such trees as the
apple and many oaks the
terminal bud has no pre-
eminence over others, and
the form of the tree is
round-topped and spread-
ing, deliquescent like that
in Fig. 33.

Most of the larger for-
est trees are intermediate
between these extremes.

Branches get their
characteristics to a

STEMS

FIG. 33. — An American Elm, with Deliquescent Trunk.

considerable degree from the relative importance of their
terminal buds. If these are mainly flower-buds, as is the case
in the horse-chestnut and some magnolias (Figs. 35, 36),

68 FOUNDATIONS OF BOTANY

the tree is characterized by frequent forking, and has
no long horizontal branches.

If the terminal bud keeps the lead of the lateral ones,
but the latter are numerous and most of them grow into
slender twigs, the delicate spray of the elm and many
birches is produced (Fig. 37).

The general effect of the branching depends much upon
the angle which each branch or twig forms with that one
froni which it springs. The angle may be quite acute, as
in the birch ; or more nearly a right angle, as in the ash
(Fig. 30). The inclination of lateral branches is due to
geotropism, just as is that of the branches of primary roots.
The vertically upward direction of the shoot which grows
from the terminal bud is also due to geotropism.

This is really only a brief way of sajdng that the grow-
ing tip of the main stem of the tree or of any branch is
made to take and keep its proper direction, whether verti-
cally upward or at whatever angle is desirable for the tree,
by the steering action of gravity. After growth has ceased
this steering action can no longer be exerted, and so a tree
that has been bent over (as, for instance, by a heavy load
of snow) cannot right itself, unless it is elastic enough to
spring back when the load is removed. The tip of the
trunk and of each branch can grow and thus become
vertical, but the old wood cannot do so.

83. Thorns as Branches. — In many trees some branches
show a tendency to remain dwarfish and incompletely
developed. Such imperfect branches forming thorns are
familiar in wild crab-apple trees and in the pear trees
which occur in old pastures in the Northeastern States. In
the honey locust very formidable branching spines spring

STEMS

from adventitious or dormant buds on the trunk or limbs.
Such spines sometimes show their true nature as branches
by bearing leaves (Fig. 34).

84. Indefinite Annual Growth. — In most of the forest
trees, and in the larger shrubs, the wood of young branches
is matured and fully

developed during the
summer. Protected
buds are formed on
the twigs of these
branches to their very
tips. In other shrubs
— for example, in the
sumac, the raspberry,
and blackberry — the
shoots continue to
grow until their soft
and immature tips are
killed by the frost.

Such a mode of growth is called indefinite
annual growth, to distinguish it from the
definite annual growth of most trees.

85. Trees, Shrubs, and Herbs. — Plants
of the largest size with a main trunk of a
woody structure are called trees. Shrubs
differ from trees in their smaller size, and

generally in having several stems which proceed from the
ground or near it or in having much-forked stems. The
witch-hazel, the dogwoods, and the alders, for instance,
are most of them classed as shrubs for this reason, though
in height some of them equal the smaller trees. Some of

FIG. 34. — Leaf -Bearing Spine
of Honey Locust.

FOUNDATIONS OF BOTANY

the smallest shrubby plants, like the dwarf blueberry, the
wintergreen, and the trailing arbutus, are only a few inches

FIG. 35. — Tip of a Branch of Magnolia, illustrating Forking due to
Terminal Flower-Buds.

A, oldest flower-bud scar ; £, C, D, scars of successive seasons after A; L, leaf-
buds ; F, flower-buds.

in height, but are ranked as shrubs because their woody
stems do not die quite to the ground in winter.

Herbs are plants whose stems above ground die every
winter.

STEMS

86. Annual, Biennial, and Perennial Plants. — Annual
plants are those which live but one year, biennials those
which live two years
or nearly so.

Some annual plants
may be made to live
over winter, flower-
ing in their second
summer. This is true
of winter wheat and
rye among cultivated
plants.

Perennial plants live for a series of
years. Many kinds of trees last for
centuries. The Californian giant redwoods, or Sequoias
(Fig. 32), which reach a height of over 300 feet under
favorable circumstances, live nearly 2000 years ; and some

FIG. 36. —A Portion of

the Branch of Fig. 35.

(Natural size.)

L— Twigs and
Branches of the
Birch.

monstrous cypress trees found in Mexico were thought by
Professor Asa Gray to be from 4000 to 5000 years old.

FOUNDATIONS OF BOTANY

87. Stemless Plants. — As will be shown later (Chap-
ter XXX), plants live subject to a very fierce competition
among themselves and exposed to almost constant attacks
from animals.

While plants with long stems find it to their advantage
to reach up as far as possible into the sunlight, the cinque-
foil, the white clover,
the dandelion, some
spurges, the knot-
grass, and hundreds
of other kinds of
plants have found
safety in hugging
the ground.

Any plant which
can grow in safety

Undei> the veiyfeet
4k<*9Hi I"- ^ of grazing animals

will be especially
likely to make its
way in the world,
since there are many
places where it can
flourish while ordi-
nary plants would be destroyed. The bitter, stemless
dandelion, which is almost uneatable for most animals,
unless cooked, which lies too near the earth to be fed
upon by grazing animals, and which bears being trodden
on with impunity, is a type of a large class of hardy weeds.
The so-called stemless plants, like the dandelion (Fig. 38),
and some violets, are not really stemless at all, but send

FIG. 38. —The Dandelion ; a so-called
Stemless Plant.

STEMS

out their leaves and flowers from a very short stem, which
hardly rises above the surface of the ground.

88. Climbing and Twining Stems.1 — Since it is essen-
tial to the health and rapid growth of most plants that
they should have free access
to the sun and air, it is not
strange that many should
resort to special devices for
lifting themselves above
their neighbors. In tropi-
cal forests, where the dark-
ness of the shade anywhere
beneath the tree-tops is so
great that few flowering
plants can thrive in it, the
climbing plants or lianas
often run like great cables
for hundreds of feet before
they can emerge into the sun-
shine above. In temperate
climates no such remarkable
climbers are found, but many
plants raise themselves for
considerable distances. The
principal means to which they resort for this purpose are :

(1) Producing roots at many points along the stem
above ground and climbing on suitable objects by means
of these, as in the English ivy (Fig. 15).

(2) Laying hold of objects by means of tendrils or
twining branches or leaf -stalks, as shown in Figs. 40, 41.

1 See Kerner and Oliver's Natural History of Plants, Vol. I, p. 669.

FIG. 39. —Lianas strangling a Palm.

FOUNDATIONS OF BOTANY

(3) Twining about any slender upright support, as
shown in Fig. 42.

89. Tendril-Climbers. — The plants which climb by
means of tendrils are important subjects for study, but
they cannot usually be managed very well in the school-
room. Continued observation soon shows that the tips of

tendrils sweep slowly about in
the air until they come in contact
with some object about which
they can coil themselves. After
the tendril has taken a few turns
about its support, the free part of
the tendril coils into a spiral and
thus draws the whole stem toward
the point of attachment, as shown
in Fig. 40. Some tendrils are
modified leaves or stipules, as
shown in Fig. 104 ; others are
modified stems.

90. Twiners. — Only a few of
the upper internodes of the stem
of a twiner are concerned in pro-
ducing the movements of the tip
of the stem. This is kept revolving in an elliptical or
circular path until it encounters some roughish and not too
stout object, about which it then proceeds to coil itself.

The movements of the younger internodes of the stems
of twiners are among the most extensive of all the move-
ments made by plants. A hop-vine which has climbed to
the top of its stake may sweep its tip continually around
the circumference of a circle two feet in diameter, and the

FIG 40. — Coiling of a Tendril
of Bryony.

STEMS

common wax-plant of the greenhouses sometimes describes
a five-foot circle, the tip moving at the rate of thirty-two
inches per hour.1 This circular motion results from
some cause not yet fully understood by botanists.2

The direction in which twiners coil about a supporting
object is almost always the same for each species of plant,
but not the same for all
species. In the hop it is as

FIG. 41. —Coiling of Petiole of Dwarf
Tropaeolmu.

FIG. 42. — Twining Stem of Hop.

shown in Fig. 42. Is it the same as in the bean ? in the
morning-glory ?

91. Underground Stems. — Stems which lie mainly or
wholly underground are of frequent occurrence and of
many kinds.

In the simplest form of rootstock (Fig. 43), such as is

1 See article on Climbing Plants, by Dr. W. J. Beal, in the American
Naturalist, Vol. IV, pp. 405-415.

2 See Strasburger, Noll, Schenk, and Schimper, Text-Book, pp. 258-262 ;
also Vines, Students' Text-Book of Botany, London and New York, 1894,
pp. 759, 760.

FOUNDATIONS OF BOTANY

found in some mints and in many grasses and sedges, the
real nature of the creeping underground stem is shown by

the presence upon its sur-
face of many scales, which
are reduced leaves. Root-
stocks of this sort often
extend horizontally for
long distances in the case
of grasses like the sea rye
grass (Plate I), which roots
itself firmly and thrives in
shifting sand-dunes. In
the stouter rootstocks, like
that of the iris (Fig. 44)
and the Caladium (Fig.
45), this stem-like charac-
ter is less evident. The
potato is an excellent ex-
ample of the short and
much-thickened under-
ground stem known as a
tuber.

It may be seen from Fig.
46 that the potatoes are
none of them borne on true
roots, but only on subter-
ranean
branches,
which are

FlG. 43. — Kootstock of Cotton-Grass (Eriophorum). S to U t 6 f

and more cylindrical than most of the roots. The " eyes "

STEMS

which they bear are rudi-
mentary leaves and buds.

Bulbs, whether coated
like those of the onion or
the hyacinth (Fig. 47), or
scaly like those of the
lily, are merely very short
and stout underground
stems, covered with closely
crowded scales or layers
which represent leaves or
the bases of leaves (Fig. 48).

The variously modified
forms of underground
stems just discussed, illus-

FIG. 44. — Roots, Rootstocks, and
Leaves of Iris.

trate in a marked way the storage
of nourishment during the winter
(or the rainless season, as the case
may be) to secure rapid growth dur-
ing the active season. It is inter-
esting to notice that nearly all of
the early-flowering herbs in temper-
ate climates, like the crocus, the
snowdrop, the spring-beauty, the

FIG. 45. — Rootstock of Cala-
dium (Colocasia).

b, terminal bud ; b', buds ar-
ranged in circles where bases
of leaves were attached ; s,
scars left by sheathing bases
of leaves.

FOUNDATIONS OF BOTANY

tulip, and the skunk-cabbage, owe their early-blooming
habit to richly stored underground stems of some kind,
or to thick, fleshy roots.

92. Condensed Stems. — The plants of desert regions
require, above all, protection from the extreme dryness of
the surrounding air, and, usually, from the excessive heat

of the sun. Ac-
cordingly, many
desert plants are
found quite desti-
tute of ordinary
foliage, exposing
to the air only a
small surface. In
the melon-cactuses
(Fig. 49) the stem
appears reduced
to the shape in
which the least
possible surface is
Fw.-.o.-part of a Potato piant. presented by a

The dark tuber in the middle is the one from which plant of give 11
the plant has grown. j^ _ ^ ^ ^

a globular form. Other cactuses are more or less cylindri-
cal or prismatic, while - still others consist of flattened
joints ; but all agree in offering much less area to the sun
and air than is exposed by an ordinary leafy plant.

93. Leaf -Like Stems. — The flattened stems of some kinds
of cactus (especially the common, showy Phyllocactus) are
sufficiently like fleshy leaves, with their dark green color
and imitation of a midrib, to pass for leaves. There are,

STEMS

Jblu. 47. — Bulb of Hyacinth.
(Exterior view and split lengthwise.)

however, a good many cases in which the stem takes on

a more strikingly leaf-like form. The common asparagus

sends up in spring shoots
that bear large scales which
are really reduced leaves.
Later in the season, what
seem like thread-like leaves
cover . the much-branched
mature plant, but these
green threads
are actually mi-
nute branches,
which perform
the work of

leaves (Fig. 50). The familiar greenhouse

climber, wrongly known as smilax (properly

called Myrsipliyllum), bears a profusion of

what appear to be delicate green leaves

(Fig. 51). Close study, however, shows that

these are really short, flattened branches,

and that each little branch springs from

the axil of a true leaf, ?, in the form

of a minute scale. Sometimes a flower

and a leaf-like branch spring from the

axil of the same scale.

1 Branches which, like those of Myrsi-

phyllum, so closely resemble leaves as to

be almost indistinguishable from them are

called cladophylls.

94. Modifiability of the Stem. — The stem may, as in the

tallest trees, in the great lianas of South American forests,

sea

FlG. 48. — Longitu-
dinal Section of
an Onion Leaf.

sea, thickened base
of leaf, forming a
bulb-scale; s,thin
sheath of leaf ; bl,
blade of the leaf ;
int, hollow inte-
rior of blade.

FOUNDATIONS OF BOTANY

&£.

FIG. 50. —A Spray of a Common Asparagus (not the edible species).

STEMS

or the rattan of Indian jungles, reach a length of many
hundred feet. On the other hand, in such "stemless"
plants as the primrose and the dandelion, the stem may be
reduced to a fraction of an inch in length. It may take

FIG. 51. — Stem of " Smilax " (Myrsiphyllum).

I, scale-like leaves ; cl, cladophyll, or leaf-like branch, growing in the axil of the
leaf ; ped, flower-stalk, growing in the axil of a leaf.

on apparently root-like forms, as in many grasses and
sedges, or become thickened by underground deposits of
starch and other plant-food, as in the iris, the potato, and
the crocus. Condensed forms of stem may exist above
ground, or, on the other hand, branches may be flat and

82 FOUNDATIONS OF BOTANY

thin enough closely to imitate leaves. In short, the stem
manifests great readiness in adapting itself to the most
varied conditions of existence.

95. Review Summary of Stems.1
Kinds of branching due to leaf arrangement .... J

Kinds of tree-trunk due to greater or less predominance f 1 -
of terminal bud . [2.

f1-

Classes of plants based on amount of woody stem . . -j 2.

U
f1-

Classes of plants based on duration of life •< 2.

Is.

f1-

Various modes of climbing -^2.

U.
f1-

Kinds of underground stem ^2.

Condensed stems above ground

Leaf-like stems

1 Where it is possible to do so, make sketches ; where this is not possible,
give examples of plants to illustrate the various kinds or classes of plants in
the summary.

CHAPTER VI

STRUCTURE OF THE STEM

STEM OF MONOCOTYLEDONOUS PLANTS

96, Gross Structure. — Refer back to the sketches of the corn-
seedling, to recall something of the early history of the -corn-stem.
Study the external appearance of a piece of corn-stem or bamboo
two feet or more in length. Note the character of the outer surface.
Sketch the whole piece and label the enlarged nodes and the nearly
cylindrical internodes. Cut across a corn-stem and examine the cut sur-
face with the magnifying glass.
Make some sections as thin as
they can be cut and examine
with the magnifying glass
(holding them up to the light)
or with a dissecting microscope.
Note the firm rind, composed
of the epidermis and underlying
tissue, the large mass of pith
composing the main bulk of the
stem, and the many little harder
and more opaque spots, which
are the cut-off ends of the
woody threads known asj^ftro-
vascular bundles (Fig. 52).

Split a portion of the stern
lengthwise into thin translucent
slices and notice whether the
bundles seem to run straight up and down its length ; sketch the
entire section x 2. Every fibro-vascular bundle of the stem passes out-
ward through some node in order to connect with some fibro-vascular

FIG. 52. — Diagrammatic Cross-Section

of Stem of Indian Corn.

cv, fibro-vascular bundles ; gc, pithy material

between bundles.

84 FOUNDATIONS OF BOTANY

bundle of a leaf. This fact being known to the student would lead
him to expect to find the bundles bending out of a vertical position
more at the nodes than elsewhere. Can this be seen in the stem
examined ?

Observe the enlargement and thickening at the nodes, and split
one of these lengthwise to show the tissue within it.

Compare with the corn-stem a piece of palmetto and a piece of
cat-brier (Smilax rotundifolia, S. hispida, etc.), and notice the simi-
larity of structure, except for the fact that the tissue in the palmetto
and the cat-brier which answers to the pith of the corn-stem is much
darker colored and harder than corn-stem pith. Compare also a piece
of rattan and of bamboo.

97. Minute Structure. — Cut a thin cross-section of the corn-stem,
examine with a low power of the microscope, and note :

(a) The rind (not true bark), composed largely of hard, thick-
walled dead cells, known as sclerenchyma fibers.

(6) The fibro-vascular bundles. Where are they most abundant ?
least abundant ?

Study the bundles in various portions of the section and notice
particularly whether some are more porous than others. Explain.
Sketch some of the outer and some of the
inner ones.

A more complicated kind of monocoty-
ledonous stem-structure can be studied to
advantage in the surgeons' splints cut from
yucca-stems and sold by dealers in surgical
supplies.

FIG. 53. -Diagrammatic 98« Mechanical Function of the
cross-section of stem of Manner of Distribution of Material

Bulrush (Scirpus), a .

Hollow cylinder with in Monocotyledonous Stems. — The
strengthening Fibers. weU-known strength and lightness of

the straw of our smaller grains and of rods of cane or
bamboo are due to their form. It can readily be shown

STRUCTURE OF THE STEM

by experiment that an iron or steel tube of moderate thick-
ness, like a piece of gas-pipe, or of bicycle-tubing, is much
stiffer than a solid rod of the same weight per foot. The
oat straw, the stems of bulrushes (Fig. 53), the cane (of
our southern canebrakes), and the bamboo are hollow
cylinders ; the
cornstalk is a
solid cylinder,
but filled with a
very light pith.
The flinty outer
layer of the
stalk, together
with the closely
packed scleren-
chyma fibers of
the outer rind
and the frequent
fibro-vascular
bundles just
within this, are
arranged in the
best way to se-
cure stiffness.
In a general
way, then, we may say that the pith, the bundles, and the
sclerenchymatous rind are what they are and where they
are to serve important mechanical purposes. But they
have other uses fully as important (Fig. 78).

99. Growth of Monocotyledonous Stems in Thickness. -
In most woody monocotyledonous stems, for a reason

FIG. 54. — Group of Date-Palms.

86 FOUNDATIONS OF BOTANY

which will be explained later in this chapter, the increase
in thickness is strictly limited. Such stems, therefore, as
in many palms (Fig. 54) and in rattans, are less conical
and more cylindrical than the trunks of ordinary trees
and are also more slender in proportion to their height.

STEM OF DICOTYLEDONOUS PLANTS

100. Gross Structure of an Annual Dicotyledonous Stem. — Study
the external appearance of a piece of sunflower-stem several inches
long. If it shows distinct nodes, sketch it. Examine the cross-
section and sketch it as seen with the magnifying glass or the dissect-
ing microscope. After your sketch is finished, compare it with Fig. 55,
which probably shows more details than your drawing, and label
the parts shown as they are labeled in that figure. Split a short
piece of the stem lengthwise through the center and study the split
surface with the magnifying glass. Take a sharp knife or a scalpel
and carefully slice and then scrape away the bark until you come to
the outer surface of a bundle.

Examine a vegetable sponge (Luffd), sold by druggists, and notice
that it is simply a network of fibro-vascular bundles. It is the skele-
ton of a tropical seed-vessel or fruit, very much like that of the wild
cucumber, common in the Central States, but a great deal larger.

The different layers of the bark cannot all be well recognized in the
examination of a single kind of stem. Examine (a) the cork which
constitutes the outer layers of the bark of cherry or birch branches
two or more years old. Sketch the roundish or oval spongy lenticels
on the outer surface of the bark. How far in do they extend ? Exam-
ine (6) the green layer of bark as shown in twigs or branches of
Forsythia, cherry, alder, box-elder, wahoo, or willow. Examine (c)
the white, fibrous inner layer, known as hard bast, of the bark of
elm, leatherwood, pawpaw, or basswood.

101. Minute Structure of the Dicotyledonous Stem. — Study, first
with a low and then with a medium power of the compound micro-
scope, thin cross-sections of clematis-stem cut just before the end of

STRUCTURE OF THE STEM

the first season's growth.1 Sketch the whole section without much
detail, and then make a detailed drawing of a sector running from
center to circumference and just wide enough to include one of the
large bundles. Label these drawings in general like Figs. 55, 56.

FIG. 55. — Diagrammatic Cross-Section of an Annual Dicotyledonous Stem.
(Somewhat magnified.)

p, pith ; fv, woody or fibro-vascular bundles ; e, epidermis ; b, bundles of hard
bast fibers of the bark.

FIG. 56. —Diagrammatic Cross-Section of One- Year-Old Aristolochia Stem.
(Considerably magnified.)

e, region of epidermis ; 6, hard bast ; o, outer or bark part of a bundle (the
cellular portion under the letter) ; w, inner or woody part of bundle ; c, cam-
bium layer ; p, region of pith ; m, a medullary ray.

The space between the hard bast and the bundles is occupied by thin-walled,
• somewhat cubical cells of the bark.

1 Clematis virginiana is simpler in structure than some of the other woody
species. Aristolochia sections will do very well.

FOUNDATIONS OF BOTANY

Note:

(a) The general outline of the section.

(6) The number and arrangement of the bundles. (How
many kinds of bundles are there?)

bundle and by the part which belongs to the bark.

(d) The way in which the pith and the outer bark are con-

nected (and the bundles separated) by the medullary rays.

FIG. 57. — One Bundle from the Preceding Figure, (x 100.)

w, wood-cells ; d, ducts. The other letters are as in Fig. 56. Many sieve-cells
occur in the region just outside of the cambium of the bundle.

Examine a longitudinal section of the same kind of stem, to find
out more accurately of what kinds of cells the pith, the bundles, and
the outer bark are built. Which portion has cells that are nearly
equal in shape, as seen in both sections V

STRUCTURE OF THE STEM

102. Mechanical Importance of Distribution of Material
in the Dicotyledonous Stem. — It is easy to see that those
tissues which are tough, like hard bast, and those which
are both tough and stiff, like wood fibers, are arranged in
a tubular fashion in young dicotyledonous stems as they
are in some monocotyledonous ones (Fig. 53). Sometimes
the interior of the stem is quite hollow, as, for example,

e ck

c w d m

FIG. 58. — Stem of Box-Elder One Year Old. (Much magnified.)
A, lengthwise (radial) section ; B, cross-section ; e, epidermis ; ck, cork ; 6, hard
bast ; s, sieve-cells ; c, cambium ; w, wood-cells ; m, medullary rays ; d,
ducts ; p, pith.

in the stems of balsams, melons, cucumbers, and squashes,
and in the flower-stalks of the dandelion. In older stems,
such as the trunks of trees, the wood forms a pretty nearly
solid cylinder.

Stiffness in dicotyledonous stems is secured mainly in
two ways:*(l) by hard bast fibers, (2) by wood fibers.
Which of these types does the stem (Fig. 55) represent?
Which does the' flax-stem (Fig. 60) represent?

90 FOUNDATIONS OF BOTANY

Notice that in both types bast fibers and wood fibers are
present, but the proportions in (1) and (2) vary greatly.

103, Kinds of Cells which compose Stems. — The stu-
dent has already seen something of cells in the seed, in
the foots of seedlings and mature plants, and in several
kinds of stems. But he will need to become acquainted
with a much larger variety of cells in the stem. The fol-
lowing materials will serve to illustrate some of the most
important forms.1

Examine, with a half-inch objective and one-inch eyepiece (or
higher power) these preparations (1-9 below) :

Study very carefully each of the sections described, find in it
the kind of cell referred to in the corresponding number (1-9) of
the following section (104), and make a good sketch of a group of
cells of each kind as actually seen under the microscope.2

(1) Very thin sections of the epidermis of a potato, some cut parallel
to the surface (tangential), others cut at right angles to the epidermis.

(2) Thin sections of the green layer of the bark of Forsythia,
spindle tree (Euonymus), or box-elder (Negundo).

(3) Thin cross-sections and longitudinal sections of the inner bark
of linden twigs, or of full-grown stems of flax.

(4) Longitudinal sections of the stem of squash or cucumber plants.

(5) Thin cross-sections of young twigs of pine or oak, cut in late
summer.

(6) Thin cross-sections and longitudinal sections, cut from pith
toward bark (radial) of young wood of sycamore, of sassafras, or of
box-elder.

(7) Thin longitudinal sections of the stem of castor-oil plant
(Ricinus) or of the stalk (peduncle) on which the fruit of the
banana is supported.

1 These studies may be made from sections cut by the pupil, by the teacher, or
by a professional hand, as circumstances may dictate. The soft bast (No. 4, see
p. 91) can best be studied in good prepared sections obtained of the dealers.

2 Nothing can do so much to make these studies valuable as for the teacher
to correct in class the errors of most frequent occurrence in the drawings, by
aid of his own camera lucida drawings of the same objects.

STRUCTURE OF THE STEM

(8) Thin longitudinal radial sections of sycamore, of sassafras,
maple, or box-elder wood.

(9) Thin sections of elder pith, sunflower-stem pith, or of so-called
Japanese " rice-paper."

104. Names of the Cells of Bark, Wood, and Pith.— No
two varieties of stems will be found to consist of just the

FIG. 59. — .4, B, C,
D, Isolated Wood-
Cells and Bast-
Cells of Linden.

A, B, wood fibers ; C,
piece of a vessel;
Z>, bast fiber; E, a
partitioned, woody
fiber from Euro-
pean ivy. (Much
magnified.)

FIG. 60. — Part of Cross-Section of Stem of Flax.
(Much magnified.)

e, epidermis ; b, hard bast ; s, sieve-cells ; w, wood.

same kinds of cells, present in the same
proportions, but it is easy to refer to illus-
trations which will serve to identify the
kinds of cells found in the studies of the
preceding section. They are :

(1)

Cork-cells of the epidermis (e.g., flax,
Fig. 60, e).

(2) Cells of the green bark (e.g., flax, Fig. 60),

between b and e.

(3) Hard bast (Fig. 60).

(4) Soft bast (e.g., flax, Fig. 60, s, for the cross-section and (very
greatly magnified) Figs. 63, 64, for the lengthwise section).1

1 The sieve-tubes shown in these figures are only one of several kinds of
cell found in soft bast, but they are the most peculiar and characteristic ones.
(See Strasburger, Noll, S,chenk, and Schimper's Text-Book, pp. 102-104.)

FOUNDATIONS OF BOTANY

(5) Cambium (e.g., Fig. 57, c).

(6) Wood-cells (e.g., Figs. 58, 72-73).

(7) Vessels or ducts (e.g., Figs. 58 and 62).

(8) Wood parenchyma (e.g., Figs. 58 and 72 in the medullary

rays).

(9) Pith (e.g., Figs. 55, 57).

105. Structure of Coniferous Wood In the wood of

the cone-bearing trees of the pine family regular ducts or

FlG. 61. FlG.,62.

FIG. 61. — A Group of Hard Bast Fibers. (Greatly magnified.)
a, cut-off ends ; b, lengthwise section of fibers.

FlG. 62. — A Lengthwise Section (greatly magnified) of a Group of Spiral Vessels
from the Stem of Sunflower. At the top of the figure some of the spiral
threads which line the vessels are seen partly uncoiled.

vessels are lacking. The main bulk of the wood is com-
posed of long cells (often called tracheids), marked with

STRUCTURE OF THE STEM

peculiar pits. These pits, when young, are shaped much
like two perforated watch-glasses, placed against a piece
of cardboard, with their concave sides toward each other

FIG. 63. FIG. 64.

FIG. 63. — Part of a Sieve-Tube from Linden.
*, sieve-plates on the cell- wall, (x about 900.)

FIG. 64. — Parts of Sieve-Tubes as found in Plants of the Gourd Family.

(Greatly magnified.)
s, s, a sieve-plate seen edgewise ; above it a similar one, surface view.

FIG. 65. —Cross-Section of Fir Wood.
s, a resin passage ; m, medullary rays. (Much magnified.)

FOUNDATIONS OF BOTANY

(see Fig. 66, t"). The cardboard represents a part of the
cell-wall common to two adjacent cells, and the watch-
glasses are like the convex border bulging into each cell.

When the cells grow old the
partition in each pit very com-
monly breaks away and leaves
a hole in the cell-wall.

106. Tissues. — A mass of
similar cooperating cells is called
a tissue.1 Two of the principal
classes which occur in the stem
are parenchymatous tissue and
prosenchymatous tissue. Paren-
chyma is well illustrated by the
green layer of the bark, by wood
parenchvma, and by pith. Its
ce^s are usually somewhat
roundish or cubical, at any rate
not many times longer than wide,
and at first pretty full of proto-
plasm. Their walls are not
generally very thick.2 Prosen-
chyma, illustrated by hard bast
and masses of wood-cells, con-
sists of thick-walled cells many
times longer than wide, containing little protoplasm and
often having little or no cell-cavity.

As a rule the stems of the most highly developed plants
owe their toughness and their stiffness mainly to prosen-

FlG. 66. — Longitudinal Radial Sec-
tion through a Rapidly Growing
Young Branch of Pine.

t , t', t", bordered pits on wood-cells ;
st, large pits where medullary
rays lie against wood-cells.
(Much magnified.)

1 See Vines' Students' Text-Book of Botany, London, 1894, pp. 131-144.

2 Excepting when they are dead and emptied, like those of old pith.

STRUCTURE OF THE STEM

OOL

FIG. 67o — Collenchymatous

and Other Tissue from Stem for instance,

of Balsam (Impatient^. ag the grow.

e, epidermis ;c, coll enchyma; .

i, intercellular spaces be- ing p 0 1 Ht

tween large parenchyma- between the
cells.

two rudi-
mentary leaves of a bean-plumule,
the cells are all of thin-walled
formative tissue and look a good
deal alike. This condition of
things is quickly succeeded by
one in which there is a cylinder
(appearing in cross-sections of the
stem as a ring) of actively growing FlG
tissue x (Fig. 68, A), lying between
the cortex r and the pith m. Soon
the cylinder x develops into a
series of separate fibro-vascular
bundles arranged as shown in
Fig. 68, B, and these again in a
short time unite, as shown at 0.
A comparison of this last portion
of the figure with that of the

chymatous tissue. In some (particu-
larly in fleshy) stems the stiffness is,
however, largely due to collenchyma, a
kind of parenchyma in which the cells
are thickened or reinforced at their
angles, as shown in Fig. 67.

107, Early History of Stem-Struc-
ture. — In the very young parts of
stems, such,

— Transverse Section
through the Hypocotyl of the
Castor-Oil Plant at Various
Stages.

, after the root has just ap-
peared outside the testa of the
seed ; B, after the hypocotyl is
nearly an inch long ; C, at the
end of germination ; r, cortex
(undeveloped bark) ; m, pith ;
st, medullary rays ; fv, fibro-
vascular bundles ; cb, layer of
tissue which is to develop into
cambium. (Considerably mag-
nified.)

96 FOUNDATIONS OF BOTANY

one-year-old Aristolochia-stem (Fig. 56) shows a decided
similarity between the two. In both cases we have the
central pith, the regularly grouped bundles, and cambium
(or in Fig. 68, (7, a tissue which will grow into cambium),
- part of it in the bundles and part of it between them.

In the young monocotyledonous stem the grouping of
the bundles is less regular than that just explained. This
is shown by Fig. 52. A much more important difference
consists in the fact that the monocotyledonous stem has
usually no permanent living cambium ring. Annual dicoty-
ledons, however, are also destitute of permanent cambium.

108. Secondary Growth. — From the inside of the cam-
bium layer the wood-cells and ducts of the mature stem
are produced, while from its outer circumference proceed
the new layers of the inner bark, composed largely of sieve-
cells and hard bast. From this mode of increase the stems
of dicotyledonous plants are called exogenous, that is, out-
side-growing. The presence of the cambium layer on the
outside of the wood in early spring is a fact well known
to the schoolboy, who pounds the cylinder cut from an
elder, willow, or hickory branch until the bark will slip
off and so enable him to make a whistle. The sweet taste
of this pulpy layer, as found in the white pine, the slippery
elm, and the basswood, is a familiar evidence of the
nourishment which the cambium layer contains.

With the increase of the fibro-vascular bundles of the
wood the space between them, which appears relatively
large in Fig. 68, becomes less and less, and the pith, which
at first extended freely out toward the circumference of
the stem, is at length only represented by thin plates, the
medullary rays.

STRUCTURE OF THE STEM 97

These are of use in storing the food which the plant
in cold and temperate climates lays up in the summer and
fall for use in the following spring, and in the very young
stem they serve as an important channel for the transfer-
ence of fluids across the stem from bark to pith, or in the

FIG. 69. — Diagram to illustrate Secondary Growth in a Dicotyledonous Stem.

7?, the first-formed bark ; p, mass of sieve-cells ; ifp, mass of sieve-cells between
the original wedges of wood ; fc, cambium of wedges of wood ; ic, cambium
between wedges ; 6, groups of bast-cells ; fh, wood of the original wedges ;
ifh, wood formed between wedges ; x, earliest wood formed ; M, pith.

reverse direction. On account, perhaps, of their impor-
tance to the plants, the cells of the medullary rays are
among the longest lived of all plant-cells, retaining
their vitality in the beech tree sometimes, it is said, for
more than a hundred years.

After the interspaces between the first fibro-vascular
bundles have become filled up with wood, the subsequent

98 FOUNDATIONS OF BOTANY

growth must take place in the manner shown in Fig. 69.
All the cambium, both that of the original wedges of wood,
fc, and that, ic, formed later between these wedges, con-
tinues to grow from its inner and from its outer face, and
thus causes a permanent increase in the diameter of the stem
and a thickening of the bark, which, however, usually at
an early period begins to peel off from the outside and
thus soon attains a pretty constant thickness.1 It will be
noticed, in the study of dicotyledonous stems more than a
year old, that there are no longer any separate fibre-vascular
bundles. The process just described has covered the origi-
nal ring of bundles with layer after layer of later formed
wood-cells, and the wood at length is arranged in a hollow
cylinder.

It is the lack of any such ring of cambium as is found
in dicotyledonous plants, or even of permanent cambium
in the separate bundles, that makes it impossible for the
trunks of most palm trees (Fig. 54) to grow indefinitely
in thickness, like that of an oak or an elm.2

109, Grafting. — When the cambium layer of any vigor-
ously growing stem is brought in contact with this layer
in another stem of the same kind or a closely similar kind
of plant, the two may grow together to form a single stem
or branch. This process is called grafting, and is much
resorted to in order to secure apples, pears, etc., of any
desired kind. A twig from a tree of the chosen variety is
grafted on to any kind of tree of the same species (or some-
times a related species), and the resulting stems will bear
the wished-for kind of fruit. Sometimes grafting comes

1 See Vines' Students' Text-Book of Botany, London, 1894, pp. 211, 212.

2 See, however, Strasburger, Noll, Schenk and Schimper's Text-Book,
pp. 138, 139.

STRUCTURE OF THE STEM

about naturally by the branches of a tree chafing against one
another until the bark is worn away and the cambium layer
of each is in contact with that of the other, or two separate
trees may be joined by
natural grafting, as is
shown in Fig. 70.

110. Stem-Strircture
of Climbing Shrubs. —
Some of the most remark-
able kinds of dicotyle-
donous stems are found
in climbing shrubs. The
structure of many of
these is too complicated
to be discussed in a
botany for beginners, but
one point in regard to
them is of much inter-
est. The bundles (as
seen in the clematis and
shown in Fig. 56) are
much more distinct than
in most other woody
stems. Even after sev-
eral years of growth the
wood is often found to be
arranged in a number of
flattish twisted strands.
It is evident that this is for the sake of leaving the
stem flexible for twining purposes, just as a wire cable is
adapted to be wound about posts or other supports, while

FIG. 70. — Two Ash Trees naturally
grafted together.

100

FOUNDATIONS OF BOTANY

a solid steel or iron rod of the same size would be too
stiff for this use.

111. The Dicotyledonous Stem, thickened by Secondary Growth. —
Cut off, as smoothly as possible, a small branch of hickory and one of
white oak above and below each of the rings of scars already mentioned

(Sect. 77), and count the
P rings of wood above and
below each ring of scars.

How do the numbers
correspond? What does
Phi this indicate ?

Count the rings of
wood on the cut-off ends
of large billets of some
of the following woods;
locust, chestnut, syca-
more, oak, hickory.

Do the successive rings
of the same tree agree in
thickness ?

Why ? or why not ?
Does the thickness of
the rings appear uniform
all the way round the stick
of wood? If not, the rea-
son in the case of an up-
right stem (trunk) is per-
haps that there was a greater spread of leaves on the side where the
rings are thickest l or because there was unequal pressure, caused by
bending before the wind.

Do the rings of any one kind of tree agree in thickness with
those of all the other kinds ? What does this show ?
In all the woods examined look for :
(a) Contrasts in color between the heartwood and the sapwood.2

1 See Sect. 118.

2 This is admirably shown in red cedar, black walnut, barberry, black
locust and osage orange.

FIG. 71. — Cross-Section of a Three- Year-Old

Linden Twig. (M\ich magnified.)
P, epidermis and corky layer of the bark ; Phi, bast ;
C, cambium layer ; Jit, annual rings of wood.

STRUCTURE OF THE STFJVf

101

(b) The narrow lines running in very young stems pretty straight
from pith to bark, in older wood extending only a little of the way
from center to bark, the medullary rays, shown in Fig. 72. *

(c?) The pores which are so grouped as to mark the divisions
between successive rings. These pores indicate the cross-sections of

vessels or ducts. Note the dis-
tribution of the vessels in the
rings to which they belong, com-

FIG. 72. — Cross-Section of Beech-Wood.
b, bark ; a, flattened cells formed near
end of each year's growth ; w, regu-
lar wood-cells ; m, medullary ray.

FIG. 73. — Longitudinal Section of
Mahogany at Right Angles to
Medullary Rays, showing Cut-
off Ends. (Much magnified.)

pare this with Figs. 58, 72, and decide at what season of the year
the largest ducts are mainly produced. Make a careful drawing
of the end-section of one billet of wood, natural size.

Cut off a grapevine several years old and notice the great size of

1 These and many other important things are admirably shown in the thin
wood-sections furnished for $4 per set of 24 by R. B. Hough, Lowville, N. Y.

FOTJOTATIONS OF BOTANY

the vessels. Examine the smoothly planed surface of a billet of red
oak that has been split through the middle of the tree (quartered
oak), and note the large shining plates formed
by the medullary rays.

Look at another stick that has been planed
away from the outside until a good-sized flat
surface is shown, and see how the medullary
rays are here represented only by their
edges.

112. Interruption of Annual Rings by
Branches ; Knots. — When a leaf -bud is
formed on the trunk or branch of a
dicotyledonous tree, it is connected with
the wood by fibro- vascular bundles. As
the bud develops into a branch, the few
bundles which it originally possessed
increase greatly in number, and at
length, as the branch grows, form a
cylinder of wood which cuts across the
annual rings, as shown in Fig. 74.
This interruption to the rings is a knot,
such as one often sees in boards and
planks. If the branch dies long before
the tree does, the knot may be buried under many rings
of wood. What is known as clear lumber is obtained
from trees that have grown in a dense forest, so that the
lower branches of the larger trees were killed by the shade
many years before the tree was felled.

In pruning fruit trees or shade trees the branches
which are removed should be cut close to the trunk. If
this is done, the growth of the trunk will bury the scar
before decay sets in.

FIG. 74. — Formation of
a Knot in a Tree-
Trunk.

R, cut-off end of stick,
showing annual rings ;
K, knot, formed by
growth of a branch.

STRUCTURE OF THE STEM

103

113. Comparison of the Monocotyledonous and the Dicotyledonous

Stem.1

MONOCOTYLEDONOUS DICOTYLEDONOUS

STEM STEM

General Structure.

A hard rind of
rather uniform struc-
ture. Bundles inter-
mixed with the pith.

Structure of
Bundles.

Growth in Thick-
ness.

Bundles closed,
that is, without per-
manent cambium.

Cells of mature
parts of stem expand
somewhat, but (in
most palms) new ones
are not found.

A complex bark,
usually on young
shoots consisting of
a corky layer, a green
layer, and a layer of
bast. Wood in an-
nual rings. Pith in
a cylinder at the cen-
ter.

Bundles open, with
permanent cambium.

wood-cells
formed throughout
growing season from
cambium ring.

114. Review Sketches and Diagrams.

(1) Monocotyledonous stem (lengthwise section).

(2) Dicotyledonous stem (lengthwise section).

(3) First appearance of bundles in dicotyledonous stem.

(4) Dicotyledonous stem five years or more old (cross-section).

(5) Various bark-cells.

(6) Various cells from wood.

(7) Pith-cells.

(8) Collenchy ma-cells.

1 This comparison applies only to most of the woody or tree-like stems.

CHAPTER VII
LIVING PARTS OF THE STEM; WORK OF THE STEM

115, Active Portions of the Stems of Trees and Shrubs.
— In annual plants generally and in the very young
shoots of shrubs and trees there are stomata or breathing
pores which occur abundantly in the epidermis, serving
for the admission of air and the escape of moisture, while
the green layer of the bark answers the same purpose that
is served by the green pulp of the leaf (Chapter XI).
For years, too, the spongy lenticels, which succeed the
stomata and occur scattered over the external surface of
the bark of trees and shrubs, serve to admit air to the
interior of the stem. The lenticels at first appear as
roundish spots, of very small size, but as the twig or shoot
on which they occur increases in diameter the lenticel
becomes spread out at right angles to the length of the
stem, so that it sometimes becomes a longer transverse slit
or scar on the bark, as in the cherry and the birch. But
in the trunk of a large tree no part of the bark except the
inner layer is alive. The older portions of the bark, such
as thS highly developed cork of the cork-oak, from which
the ordinary stoppers for bottles are made, sometimes
cling for years after they are dead and useless except as a
protection for the parts beneath against mechanical injuries
or against cold. But in many cases, as in the shell-bark hick-
ory and the grapevine, the old bark soon falls off in strips ;
in birches it finally peels off in bands around the stem.

104

LIVING PARTS OF THE STEM 105

The cambium layer is very much alive, and so is the
young outer portion of the wood. Testing this "sap-
wood," particularly in winter, shows that it is rich in
starch and proteids.

The heartwood of a full-grown tree is hardly living,
unless the cells of the medullary rays retain their vitality,
and so it may be that wood of this kind is useful to the
tree mainly by giving stiffness to the trunk and larger
branches, thus preventing them from being easily broken
by storms.

It is, therefore, possible for a tree to flourish, sometimes
for centuries, after the heartwood has much of it rotted
away and left the interior of the trunk hollow, as shown
hi Fig. 75.

116, Uses of the Components of the Stem. — There is a
marked division of labor among the various groups of cells
that make up the stem of ordinary dicotyledons, particu-
larly in the stems of trees, and it will be best to explain
the uses of the kinds of cells as found in trees, rather than
in herbaceous plants. A few of the ascertained uses of
the various tissues are these:

The pith forms a large part of the bulk of very young
shoots, since it is a part of the tissue of comparatively
simple structures amid which the nbro-vascular bundles
arise. In mature stems it becomes rather unimportant,
though it often continues for a long time to act as a store-
house of food.

The medullary rays in the young shoot serve as a chan-
nel for the transference of water and plant-food in a liquid
form across the stem, and they often contain much stored
food.

106

FOUNDATIONS OF BOTANY

FIG. 75. — Pioneer's Cabin, a Very Large Hollow Sequoia.

The vessels carry water upward and air downward
through the stem.

The wood-cells of the heartwood are useful only to give

LIVING PARTS OF THE STEM 107

stiffness to the stem. Those of the sapwood, in addition
to this work, have to carry meet of the water from the
roots to the leaves and other distant portions of the plant.

The cambium layer is the region in which the annual
growth of the tree takes place (Figs. 69, 71).

The most important portion of the inner bark is that
which consists of sieve-tubes, for in these digested and
elaborated plant-food is carried from the leaves toward the
roots.

The green layer of the bark in young shoots does much
toward collecting nutrient substances, or raw materials,
and preparing the food of the plant from air and water,
but .this work may be best explained in connection with
the study of the leaf (Chapter XI).

117. Movement of Water in the Stem. — The student
has already learned that large quantities of water are taken
up by the roots of plants.

Having become somewhat acquainted with the structure
of the stem, he is now in a position to investigate the
question how the various fluids, commonly known as sap,
travel about in it.1 It is important to notice that sap is
by no means the same substance everywhere and at all
times. As it first makes its way by osmotic action inward
through the root-hairs of the growing plant it differs but
little from ordinary spring water or well water. The
liquid which flows from the cut stem of a "bleeding"
grapevine which has been pruned just before the buds have
begun to burst in the spring, is water with a 'little muci-
laginous or slimy material added. The sap which is

1 See the paper on "The So-called Sap of Trees and its Movements," by
Professor Charles R. Barnes, Science, Vol. XXI, p. 535.

108

FOIL IS OF EOT

obtained from maple trees" .A lat« winter or early spring,
and is boiled down for sy.-np or sugar, is still richer in
nutritious material than the water of the grapevine, while
the elaborated sap which is sent so abundantly into the ear
of corn, at its period of filling out, or into the growing
pods of beans and peas, or into the rapidly forming acorn
or the chestnut, contains great stores of food, suited to sus-
tain plant or animal life.

EXPERIMENT XXI

Rise of Water in Stems. — Cut some short branches from an
apple tree or a cherry tree and stand the lower end of each
in red ink; try the same experiment with twigs of oak, ash,
or other porous wood, and after some hours1 examine with

the magnifying glass and with the
microscope, using the 2-inch objective,
successive cross-sections of one or more
twigs of each kind. Note exactly the
portions through which the ink has
traveled. Pull off the leaves from one
of the stems after standing in the eosin
solution, and notice the spots on the
leaf-scar through which the eosin has
traveled. These spots show the posi-
tions of the leaf-traces, or fibre-vascular
bundles, connecting the stem and the
leaf. Repeat with several potatoes, cut
crosswise through the middle. Try
also some monocotyledonous stems,
such as those of the lily or asparagus.

For the sake of comparison between
FIG. 76. — A Cutting girdled and ,

sending down Roots from the ™ots and stems, treat ^ any convenient

Upper Edge of the Girdled King, root, such as a parsnip, in the same way.

1 If the twigs are leafy and the room is warm, only from 5 to 30 minutes
may be necessary.

LIVING PARTS OF THE STEM

109

Examine longitudinal sections o^ some of the twigs, the potatoes,
and the roots. In drawing conclusions about the channels through
which the ink has risen (those through which the newly absorbed
soil-water most readily trav-
els), bear in mind the fact
that a slow soakage of the
red ink will take place in
all directions, and therefore
pay attention only to the
strongly colored spots or
lines.

What conclusions can be
drawn from this experiment
as to the course followed by
the sap?

From the familiar
facts that ordinary for-
est trees apparently
flourish as well after the
almost complete decay
and removal of their
heartwood, and that
many kinds will live
and grow for a consider-
able time after a ring of
bark extending all round
the trunk has been re-
moved, it may readily be
inferred that the crude sap in trees must rise through some
portion of the newer layers of the wood. A tree girdled
by the removal of a ring of sapwood promptly dies.

118. Downward Movement of Liquids. — Most dicoty-
ledonous stems, when stripped of a ring of bark and then

FIG. 77. — Channels for the Movement of
Water, upward and downward.

The heavy black lines in roots, stems, and
leaves show the course of the fibro-vascular
bundles through which the principal move-
ments of water take place.

110

FOUNDATIONS OF BOTANY

stood in water, as shown in Fig.
bell-jar, develop roots only at or

FIG. 78. — Diagrammatic Cross-Section of a
Bundle from Sugar-Cane, showing Channels
for Air and Water. (Magnified.)

Air travels downward through the two large
ducts d (and the two smaller ones between
them). Water travels upward through the
ducts and through the wood-cells in the
region marked w. Water with dissolved
plant-food travels downward through the
sieve-cells in the region marked s.

76, and covered with a
near the upper edge of
the stripped portion,1
and this would seem to
prove that such stems
send their building ma-
terial — the elaborated
sap — largely at any rate
down through the bark.
Its course is undoubt-
edly for the most part
through the sieve-cells
(Figs. 63, 64), which are
admirably adapted to
convey liquids. In ad-
dition to these general
upward and downward
movements of sap, there
must be local transfers

laterally through the stem, and
these are at times of much im-
portance to the plant.

Since the liquid building mate-
rial travels straight down the

. , . i (, . , FIG. 79. — Unequal Growth of Kings

Stem, that Side O± the Stem On Of Wood in nearly Horizontal
Which the manufacture of SUch Stemof a Juniper. (Natural size.)

material is going on most rapidly should grow fastest.

1 This may be made the subject of a protracted class-room experiment.
Strong shoots of willow should be used for the purpose.

LIVING PARTS OF THE STEM 111

Plant-food is made out of the raw materials by the leaves,
and so the more leafy side of a tree forms thicker rings
than the less leafy side, as shown in Fig. 79.

119, Rate of Movement of Water in the Stem. — There
are many practical difficulties in the way of ascertaining
exactly how fast the watery sap travels from the root to
the leaves. It is, however, easy to illustrate experimen-
tally the fact that it does rise, and to give an approximate
idea of the time required for its ascent. The best experi-
ment for beginners is one which deals with an entire
plant under natural conditions.

EXPERIMENT XXII

Wilting and Recovery. — Allow a fuchsia or a hydrangea1 which
is growing in a flower-pot to wilt considerably for lack of watering.
Then water it freely and record the time required for the leaves to
begin to recover their natural appearance and position, and the
time fully to recover.

The former interval of time will give a very rough idea
of the time of transfer of water through the roots and the
stem of the plant. From this, by measuring the approxi-
mate distance traveled, a calculation could be made of the
number of inches per minute that water travels in this
particular kind of plant, through a route which is partly
roots, partly stem, and partly petiole. Still another
method is to treat leafy stems as the student in Exp. XXI
treated the twigs which he was examining, and note care-
fully the rate of ascent of the coloring liquid. This plan
is likely to give results that are too low, still it is of some
use. It has given results varying from 34 inches per

1 Hydrangea hortensia.

112 FOUNDATIONS OF BOTANY

hour for the willow to 880 inches per hour for the sun-
flower. A better method is to introduce the roots of the
plant which is being experimented upon into a weak
solution of some chemical substance which is harmless to
the plant and which can readily be detected anywhere in
the tissues of the plant by chemical tests. Proper tests
are then applied to portions of the stem which are cut
from the plant at short intervals of time.

Compounds of the metal lithium are well adapted for
use in this mode of experimentation.

120. Causes of Movements of Water in the Stem. — Some
of the phenomena of osmosis were explained in Sect. 62,
and the work of the root-hairs was described as due to
osmotic action.

Root-pressure (Sect. 66), being apparently able to sus-
tain a column of water only 80 or 90 feet high at the
most, and usually less than half this amount, would be
quite insufficient to raise the sap to the tops of the tallest
trees, since many kinds grow to a height of more than 100
feet. Our Californian " big trees," or Sequoias, reach
the height of over 300 feet, and an Australian species of
Eucalyptus, it is said, sometimes towers up to 470 feet.
Root-pressure, then, may serve to start the soil-water on
its upward journey, but some other force or forces must
step in to carry it the rest of the way. What these other
forces are is still a matter of discussion among botanists.

The slower inward and downward movement of the sap
may be explained as due to osmosis. For instance, in the
case of growing wood-cells, sugary sap from the leaves
gives up part of its sugar to form the cellulose of which
the wood-cells are being made.

LIVING PARTS OF THE STEM 113

This loss of sugar would cause a flow of rather watery
sap to take place more rapidly than usual from the grow-
ing wood to the leaves, while at the same time a slow
transfer of the dissolved sugar will be set up from leaves
to wood. The water, as fast as it reaches the leaves, will
be thrown off in the form of vapor, so that they will
not become distended with water, while the sugar will be
changed into cellulose and built into new wood-cells as fast
as it reaches the region where such cells are being formed.

Plants in general l readily change starch to sugar, and
sugar to starch. When they are depositing starch in any
part of the root or stem for future use, the withdrawal of
sugar from those portions of the sap which contain it
most abundantly gives rise to a slow movement of dis-
solved particles of sugar in the direction of the region
where starch is being laid up.

121. Storage of Food in the Stem. — The reason why the
plant may profit by laying up a food supply somewhere
inside its tissues has already been suggested (Sect. 91).

The most remarkable instance of storage of food in the
stem is probably that of sago-palms, which contain an
enormous amount, sometimes as much as 800 pounds, of
starchy material in a single trunk. But the commoner
plants of temperate regions furnish plenty of examples of
deposits of food in the stem. As in the case of seeds and
roots, starch constitutes one of the most important kinds
of this reserve material of the stem, and since it is easier
to detect than any other food material which the plant
stores, the student will do well to spend time in looking
for starch only.

1 Not including most of the flowerless and very low and simple kinds.

114 FOUNDATIONS OF BOTANY

Cut thin cross-sections of twigs of some common deciduous tree
or shrub, in its early winter condition, moisten with iodine solution,
and examine for starch with a moderately high power of the micro-
scope. Sketch the section with a pencil, coloring the starchy por-
tions with blue ink, used with a mapping pen, and describe exactly
in what portions the starch is deposited.

122. Storage in Underground Stems. — The branches
and trunk of a tree furnish the most convenient place
in which to deposit food during winter to begin the
growth of the following spring. But in those plants
which die down to the ground at the beginning of winter
the storage must be either in the roots, as has been
described in Sect. 58, or in underground portions of
the stem.

Rootstocks, tubers, and bulbs seem to have been de-
veloped by plants to answer as storehouses through the
winter (or in some countries through the dry season) for
the reserve materials which the plant has accumulated
during the growing season. The commonest tuber is the
potato, and this fact and the points of interest which it
represents make it especially desirable to use for a study
of the underground stem in a form most highly specialized
for the storage of starch and other valuable products.

123. A Typical Tuber : the Potato. — Sketch the general outline
of a potato, showing the attachment to the stem from which it grew.1

Note the distribution of the "eyes," — are they opposite or alter-
nate ? Examine them closely with the magnifying glass and then with
the lowest power of the microscope. What do they appear to be ?

If the potato is a stem, it may branch, — look over a lot of pota-
toes to try to find a branching specimen. If such a one is secured,
sketch it.

1 Examination of a lot of potatoes will usually discover specimens with an
inch or more of attached stem.

LIVING PARTS OF THE STEM 115

Note the little scale overhanging the edge of the eye, and see if
you can ascertain what this scale represents.

Cut the potato across, and notice the faint broken line which
forms a sort of oval figure some distance inside the skin.

Place the cut surface in eosin solution, allow the potato to stand
so for many hours, and then examine, by slicing off pieces parallel
to the cut surface, to see how far and into what portions the solution
has penetrated. Refer to the notes on the study of the parsnip
(Sect. 56), and see how far the behavior of the potato treated with
eosin solution agrees with that of the parsnip so treated.

Cut a thin section at right angles to the skin, and examine with a
high power. Moisten the section with iodine solution and examine
again.

If possible, secure a potato which has been sprouting in a warm
place for a month or more (the longer the better), and look near
the origins of the sprouts for evidences of the loss of material from
the tuber.

EXPERIMENT XXIII

Use of the Corky Layer. — Carefully weigh a potato, then pare
another larger one, and cut portions from it until its weight is made
approximately equal to that of the first one. Expose both freely to
the air for some days and reweigh. What does the result show in
regard to the use of the corky layer of the skin?

124, Morphology of the Potato. — It is evident that in
the potato we have to do with a very greatly modified
form of stem. The corky layer of the bark is well repre-
sented, and the loose cellular layer beneath is very greatly
developed ; wood is almost lacking, being present only in
the very narrow ring which was stained by the red ink,
but the pith is greatly developed and constitutes the prin-
cipal bulk of the tuber. All this is readily understood if
we consider that the tuber, buried in and supported by
the earth, does not need the kinds of tissue, which give

116 FOUNDATIONS OF BOTANY

strength, but only those which are well adapted to store
the requisite amount of food.

125, Structure of a Bulb ; the Onion. — Examine the external
appearance of the onion and observe the thin membranaceous skin
which covers it. This skin consists of the broad sheathing bases of
the outer leaves which grew on the onion plant during the summer.
Remove these and notice the thick scales (also formed from bases
of leaves as shown in Fig. 48) which make up the substance of the
bulb.

Make a transverse section of the onion at about the middle and
sketch the rings of which it is composed. Cut a thin section from
the interior of the bulb, examine with a moderate power of the
microscope, and note the thin-walled cells of which it is composed.

Split another onion from top to bottom and try to find :

(a) The plate or broad flattened stem inside at the base (Fig. 47).

(5) The central bud.

(d) In some onions (particularly large, irregular ones) the bulblets
or side buds arising in the axes of the scales near the base.

Test the cut surface for starch.

126. Sugar in the Onion. — G-rape sugar is an important
substance among those stored for food by the plant. It
received its name from the fact that it was formerly
obtained for chemical examination from grapes. Old
dry raisins usually show little masses of whitish material
scattered over the skin which are nearly pure grape sugar.
Commercially it is now manufactured on an enormous
scale from starch by boiling with diluted sulphuric acid.
In the plant it is made from starch by processes as yet
imperfectly understood, and another sugar, called maltose,
is made from starch in the seed during germination.

Both grape sugar and maltose (and hardly any other
substances) have the power of producing a yellow or

LIVING PARTS OF THE STEM 117

orange color and throwing down an orange or reddish
deposit, when they are added to a brilliant blue alkaline
solution of copper, known as FeJiling's solution.1 The
color or deposit will not appear until the solution has
been heated, to boiling.

EXPERIMENT XXIV

Testing for Grape Sugar. — Heat to boiling in a test-tube or a
small beaker some weak syrup of grape sugar or some honey, much
diluted with water. Add Fehling's solution, a few drops at a time,
until a decided orange color appears. Repeat the test with the
water in which some slices of onion have been boiled, filtering the
water through a paper filter and heating again to boiling before
adding the test solution.2

127. Proteids in the Onion. — Since the onion grows
so rapidly on being planted in the spring, there must be
a large supply of food in the bulb ; there may be other
substances present besides sugar.

EXPERIMENT XXV

•
Testing an Onion for Other Stored Food. — Test a rather thick

slice of onion by heating it in a porcelain evaporating dish with a
little strong nitric acid until the latter begins to boil and the onion
becomes somewhat softened.8 Rinse off the slice of onion in a stream
of water, then pour on it a few drops of ammonium hydrate and
observe any change of color. What is proved ? See Sect. 29.

128, Tabular Review of Experiments.

[Continue the table from Sect. 74.]

1 For the preparation of the solution see Handbook.

2 The deposit will in this case, even if orange at first, finally become black,
probably owing to the presence of sulphur in the onion.

3 Do not allow the acid to touch the clothing, the hands, or any metallic
object.

118 FOUNDATIONS OF BOTANY

129. Review Summary of Work of Stem.

f in young dicotyledonous stems
Channels for upward movement J in dicotyledonous stems several

of water | years old

I in monocotyledonous stems

Channels for downward move- f in dicotyledonous stems . . .
ment of water \ in monocotyledonous stems . .

Channels for transverse movements .

Rate of upward movement

C where stored

Storage of plant-food •< kinds stored

louses . . .

CHAPTER VIII
BUDS

130. Structure of Buds. — While studying twigs in their
winter condition, as directed in Sects. 77, 78, the student
had occasion to notice the presence, position, and arrange-
ment of buds on the branch, but he was not called upon
to look into the details of their structure. The most natu-
ral time to do this is just before the "study of the leaf is
begun, since leafy stems spring from buds, and the rudi-
ments of leaves in some form must be found in buds.

131. The Horse-Chestnut Bud. — Examine one of the lateral buds
on a twig in its winter or early spring condition.1

Make a sketch of the external appearance of the buds as seen with
a magnifying glass.

How do the scales with which it is
covered lie with reference to those
beneath them?

Notice the sticky coating on the scales.

Are the scales opposite or alternate? 2~

Remove the scales in pairs, placing
them in order on a sheet of paper, thus :

Make the distance from 1 to 1 as much
as 6 or 8 inches.

How many pairs are found ?

Observe as the scales are removed whether the sticky coating is

1 The best possible time for this examination is just as the buds are begin-
ning to swell slightly in the spring. The bud of buckeye or of cottonwood
will do for this examination, though each is on a good deal smaller scale than
the horse-chestnut bud. Buds may be forced to open early by placing twigs
in water in a very warm, light place for many weeks.

119

120

FOUNDATIONS OF BOTANY

thicker on the outside or the inside of each scale, and whether it
is equally abundant on all the successive pairs.
What is the probable use of this coating ?

Note the delicate veining of some of the scales as seen through

the magnifying glass. What does
this mean?

Inside the innermost pair are
found two forked woolly objects ;
what are these ?

Compare with Figs. 87 and 107.
Their shape could be more readily
observed if the woolly coating were
removed.

Can you suggest a use for the
woolly coating?

Examine a terminal bud in the
same way in which you have just
studied the lateral bud.

Does it contain any parts not
found in the other?

What is the appearance of these
parts ?

W'hat do they represent ?
If there is any doubt about their
nature, study them further on a
. horse-chestnut tree during and im-
mediately after the process of leaf-
ing out in the spring.

For comparison study at least one
to of the following kinds of buds in
their winter or early spring condi-
tion : hickory, butternut, beech, ash, magnolia (or tulip tree), lilac,
balm of Gilead, cottonwood, cultivated cherry.1

1 Consult the account of the mode of studying buds in Professor W. F.
Ganong's Teaching Botanist, pp. 208-210. If some of the buds are studied at
home, pupils will have a better chance to examine at leisure the unfolding
process.

FIG. 80. —Dissected Bud of Buckeye
(^Esculus macrostachya), showing
Transitions from Bud-Scales
Leaves.

BUDS

121

132. Nature of Bud-Scales. - - The
fact that the bud-seales are in certain
cases merely imperfectly developed
leaves or leaf-stalks is often clearly
manifest from the series of steps con-
necting the bud-scale on the one hand
with the young leaf on the other, which
may be found in many opening buds,
as illustrated by Fig. 80. In other
buds the scales are not imperfect leaves,
but the little appendages (stipules, Figs.
98, 99) which occur at the bases of
leaves. This kind of bud-scale is
especially well shown in the magnolia
and the tulip tree.

133. Naked Buds. — All of the buds
above mentioned are winter buds, capa-
ble of living through the colder months
of the year, and are scaly buds.

In the herbs of temperate climates,
and even in shrubs and trees of tropical
regions, the buds are often naked, that
is, nearly or quite destitute of scaly
coverings (Fig. 81).

Make a study of the naked buds of any
convenient herb, such as one of the common
" geraniums " (Pelargonium), and record what
you find in it.

134. Position of Buds. — The dis- FlG- 81> ~ Tip of Branch

of Ailanthus in Winter

tinction between lateral and terminal condition, showing

very Large Leaf-Scars
and nearly Naked Buds.

buds has already been alluded to.

122

FOUNDATIONS OF BOTANY

The plumule is the first terminal bud which the plant
produces. Lateral buds are usually axillary, as shown in
Fig. 82, that is, they grow in the angle formed by the
leaf with the stem (Latin axilla, armpit). But not infre-
quently there are several buds grouped in some way about

PIG. 82.-

Alternate Leaves of Cultivated Cherry, with Buds in
their Axils, in October.

a single leaf -axil, either one above the other, as in the
butternut (Fig. 84), or grouped side by side, as in the red
maple, the cherry, and the box-elder (Fig. 83).

In these cases all the buds except the axillary one are
called accessory or supernumerary buds.

135. Leaf-Buds and Flower-Buds ; the Bud an Undevel-
oped Branch. — Such buds as the student has so far

BUDS

123

examined for himself are not large enough to show in the
most obvious way the relation of the parts and their real
nature.

Fortunately, it is easy to obtain a gigantic terminal bud
which illustrates perfectly the structure and arrangement
of the parts of buds in
general.

Examine and sketch a rather
small, firm cabbage, preferably
a red one, which has been split
lengthwise through the center 1
and note

(a) The short, thick, conical
stem.

(&) The crowded leaves
which arise from the stem, the
lower and outer ones largest
and most mature, the upper
and innermost ones the small-
est of the series.

Compare the section of the cabbage -with Fig. 86.

Most of the buds so far considered were leaf-buds, that
is, the parts inside of the scales would develop into leaves,
and their central axes into stems ; but some were mixed
buds, that is, they contained both leaves and flowers in an
undeveloped condition.

Flower-buds contain the rudiments of flowers only.

Sometimes, as in the black walnut and the butternut,
the leaf-buds and flower-buds are readily distinguishable

1 Half of a cabbage will be enough for the entire division.

FIG. 83. —Accessory Buds of Box-Elder
(Negundo). (Magnified.)

A, front view of group.

.B, two groups seen in profile.

124

FOUNDATIONS OF BOTANY

by their difference in form, while in other cases, as in the
cultivated cherry, the difference in form is but slight.
The rings of scars about the twig, shown in Figs. 82
and 85, mark the place where the bases
of bud-scales were attached. A little
examination of the part of the twig
which lies outside of this ring, as shown
in Fig. 82, will lead one to the conclu-
sion that this portion has all grown in
the one spring and summer since the
bud-scales of that particular ring dropped
off. Following out this suggestion, it is
easy to reckon the age of any moder-
ately old portion of a branch, since it is
equal to the number of segments between
the rings. In rapidly growing shoots of
willow, poplar, and similar trees, 5 or 10
feet of the length may be the growth of
a single year, while in the lateral twigs
of the hickory, apple, or cherry the yearly
increase may be but a fraction of an inch.
Such fruiting " spurs " as are shown in
Fig. 85 are of little use in the permanent

gr°wth °f the tree' and p°plars' elms>

soft maples and other trees shed the

I leaf-scar ;«*, axil- w t f th Whatever

lary bud ; a, a, ac- *• J

the amount of this growth, it is but the
lengthening out and development of the
bud, which may be regarded as an undeveloped stem or
branch, with its intern-odes so shortened that successive
leaves seem almost to spring from the same point.

(Reduced.)

cessory buds ;
terminal bud.

BUDS

125

136. Vernation. — Procure a considerable number of buds which
are just about to burst, and others which have begun to open. Cut
each across with a razor or very sharp scalpel ; examine first with
the magnifying glass, and then with the lowest power of the micro-
scope. Pick to pieces other buds of the same
kinds under the magnifying glass, and report
upon the manner in which the leaves are
packed away.

The arrangement of leaves in the
bud is called vernation; some of the

principal modes are shown in Fig. 86.

f... sc

-1900
-—1899

ax__

FIG. 85. —A slowly grown Twig
of Cherry, 3 inches long and
about ten years old.

The pointed bud I is a leaf -bud ;
the more obtuse accessory
buds /, / are flower-buds.

FIG. 86.

J5, a twig of European elm ; A, a longitudi-
nal section of the buds of B (considerably
magnified) ; ax, the axis of the bud, which
will elongate into a shoot ; sc, leaf-scars.

In the cherry the two halves of the leaf are folded
together flat, with the under surfaces outward ; in the
walnut the separate leaflets, or parts of the leaf, are folded

126

FOUNDATIONS OF BOTANY

flat and then grouped into a sort of cone ; in the snow-
ball each half of the leaf is plaited in a somewhat fan-like
manner, and the edges of the two halves are then brought
round so as to meet; in the lady's mantle the fan-like
plaiting is very distinct ; in the wood sorrel each leaflet

FIG. 87, 1. — Types of Vernation.
1, 2, Cherry ; 3, 4, European walnut ; 5, 6, snowball ; 7, lady's mantle ; 8, oxalis.

is folded smoothly, and then the three leaflets packed
closely side by side. All these modes of vernation and
many others have received accurate descriptive names by
which they are known to botanists.

137. Importance of Vernation. — The significance of ver-
nation is best understood by considering that there are two

BUDS 127

important purposes to be served ; the leaves must be
stowed as closely as possible in the bud, and upon begin-
ning to open they must be protected from too great heat
and dryness until they have reached a certain degree of
firmness. It may be inferred from Fig. 87, I, that it is
common for very young leaves to stand vertically. This
protects them considerably from the scorching effect of the
sun at the hottest part of the day. Many young leaves,
as, for instance, those of the silver-leafed poplar, the pear,
the beech, and the mountain ash, are sheltered and pro-

FIG. 87, II. — Development of an Oxalis Leaf.

A, full-grown leaf ; B, rudimentary leaf, the leaflets not yet evident ; C, more
advanced stage, the leaflets appearing ; D, a still more advanced stage ;
B, C, and Z>, considerably magnified.

tected from the attacks of small insects by a coating of
wool or down, which they afterwards lose. Those of the
tulip tree are enclosed for a little time in thin pouches,
which serve as bud-scales, and thus entirely shielded from
direct contact with the outside air (see Sect. 117).

138. Dormant Buds. — Generally some of the buds on a
branch remain undeveloped in the spring, when the other
buds are beginning to grow, and this inactive condition
may last for many seasons. Finally the bud may die, or
some injury to the tree may destroy so many other buds
as to leave the dormant ones an extra supply of food, and

128 FOUNDATIONS OF BOTANY

this, with other causes, may force them to develop and to
grow into branches.

Sometimes the tree altogether fails to produce buds at
places where they would regularly occur. In the lilac the
terminal bud usually fails to appear, and the result is con-
stant forking of the branches.

139. Adventitious Buds. — Buds which occur in irregu-
lar places, that is, not terminal nor in or near the axils of
leaves, are called adventitious buds ; they may spring from
the roots, as in the silver-leafed poplar, or from the sides
of the trunk, as in our American elm. In many trees, for
instance willows and maples, they are sure to appear after
the trees have been cut back. Willows are thus cut back
or pollarded, as shown in Plate II, in order to cause them
to produce a large crop of slender twigs suitable for
basket-making.

Leaves rarely produce buds, but a few kinds do so when
they are injured. Those of the bryophyllum, a plant allied
to the garden live-for-ever, when they are removed from
the plant while they are still green and fresh, almost always
send out buds from the margin. These do not appear at
random but are borne at the notches in the leaf-margin and
are accompanied almost from the first by minute roots.

Pin up a bryophyllum leaf on the wall of the room or
lay it on the surface of moist earth, and follow, day by day,
the formation and development of the buds which it may
produce.

This plant seems to rely largely upon leaf-budding to
reproduce itself, for in a moderately cool climate it rarely
flowers or seeds, but drops its living leaves freely, and from
each such leaf one or several new plants may be produced.

PLATE II. _ Pollarded Willows

BUDS 129

140. Review Summary of Chapter VIII.

Coverings . . . -- -V -

leaf-buds

Contents . . J flower-buds
I mixed buds

regular

Classes of buds as re-
position . .

irregular

Make a sketch of Fig. 82 as it looked in June of the same sum-
mer ; also as it would look the following June.

CHAPTER IX
LEAVES

141. The Elm Leaf. — Sketch the leafy twig of elm that is sup-
plied to you.1

Report on the following points :
(a) How many rows of leaves ?

(5) How much overlapping of leaves when the twig is held with
the upper sides of the leaves toward you ? Can you suggest a reason
for this ? Are the spaces between the edges of the leaves large or
small compared with the leaves themselves ?

Pull off a single leaf and make a very careful sketch of its under
surface, about natural size. Label the broad expanded part the blade,
and the stalk by which it is attached to the twig, leaf-stalk or petiole.
Study the outline of the leaf and answer these questions :
(a) What is the shape of the leaf taken as a whole ? (See Fig.
88.) Is the leaf bilaterally symmetrical, i.e., is there a middle line
running through it lengthwise, along which it could be so folded
that the two sides would precisely coincide ?

(6) What is the shape of the tip of the leaf? (See Fig. 89.)
(c) Shape of the base of the leaf? (See Fig. 90.)

(rf) Outline of the margin of the leaf? (See Fig. 93.)
Notice that the leaf is traversed lengthwise by a strong midrib
and that many so-called veins run from this to the margin. Are

1 Any elm will answer the purpose. Young strong shoots which extend
horizontally are best, since in these leaves are most fully developed and their
distribution along the twig appears most clearly. Other good kinds of leaves
with which to begin the study, if elm leaves are not available, are those of
beech, oak, willow, peach, cherry, apple. Most of the statements and direc-
tions above given would apply to any of the leaves just enumerated. If this
chapter is reached too early in the season to admit of suitable material being
procured for the study of leaf arrangement, that topic may be omitted until
the leaves of forest trees have sufficiently matured.

130

LEAVES

131

FIG. 88. — General Outline of Leaves.

a, linear ; 6, lanceolate ; c, wedge-shaped ; d, spatulate ; e, ovate ; /, obovate ;
g, kidney-shaped ; h, orbicular ; i, elliptical.

/ 9

FIG. 89.— Tips of Leaves.

a, acuminate or taper-pointed ; b, acute ; c, obtuse ; d, truncate ; e, retuse ; /,
emarginate or notched ; g (end leaflet), obcordate ; h, cuspidate, — the point
sharp and rigid ; i, mucronate, —the point merely a prolongation of the midrib.

132

FOUNDATIONS OF BOTANY

FIG. 90. — Shapes of Bases of Leaves.

1, heart-shaped (unsymmetrically) ; 2, arrow-
shaped ; 3, halberd-shaped.

FIG. 91. — Peltate Leaf of
Tropaeolum.

FIG. 92.

A; runcinate leaf of dandelion ; B,
lyrate leaf.

FIG. 93. — Shapes of Margins

of Leaves.

a (1), finely serrate ; (2), coarsely
serrate ; (3), doubly serrate.
6 (1), finely dentate ; (2) , sinuate
dentate ; (3), doubly dentate.
c, deeply sinuate, d, wavy.
e (1), crenate or scalloped ; (2),
doubly crenate.

LEAVES

133

these veins parallel ? Hold the leaf up towards the light and see
how the main veins are connected by smaller ueinlets. Examine
with your glass the leaf as held to the light
and make a careful sketch of portions of
one or two veins and the intersecting vein-
lets. How is the course of the veins shown
on the upper surface of the leaf ?

Examine both surfaces of the leaf with
the glass and look for hairs distributed on
the surfaces. Describe the manner in which
the hairs are arranged.

FIG. 94.— Netted Vein-
ing (pinnate) in the
Leaf of the Foxglove.

The various forms of leaves are
classed and described by botanists with
great minuteness,1 not simply for the
study of leaves themselves, but also
because in classifying and describing
plants the characteristic forms of the
leaves of many kinds of plants form
a very simple
and ready

means of distinguishing them

from each other and identifying

them. The student is not ex-
pected to learn the names of the

several shapes of leaves as a

whole or of their bases, tips, or

margins, except in those cases

in which he needs to use and

apply them.

Many of the words used to describe the shapes of leaves

are equally applicable to the leaf-like parts of flowers.

FIG. 95. — jetted Veining (pal-
mate) in Leaf of Melon.

See Kerner and Oliver's Natural History of Plants, Vol. I, pp. 623-637.

134

FOUNDATIONS OF BOTANY

142. The Maple Leaf. — Sketch the leafy twig.
Are the leaves arranged in rows like those of the elm ? How are
they arranged ?

How are the petioles distorted from their natural positions to
bring the proper surface of the leaf upward toward the light ?

Do the edges of these leaves show larger spaces between them
than the elm leaves did, i.e., would a spray of maple intercept the
sunlight more or less perfectly than a spray of
elm ? Pull off a single leaf and sketch its lower
surface, about natural size.

Of the two main parts whose names have
already been learned (blade and petiole), which
is more developed in the maple than in the
elm leaf?
Describe :

(a) The shape of the maple leaf as a whole.
To settle this, place the leaf on paper, mark the
positions of the extreme points and connect
these by a smooth line.

(&) Its outline as to main divisions : of what
The blade of the leaf is kind and how many.

FIG. 96. — Pinnately
Divided Leaf of
Celandine.

discontinuous, con-
sisting of several por-
tions between which
are spaces in which
one part of the blade
has been developed.

,-p,.

Compare the mode of veining or venation of
the elm and the maple leaf by making a
diagram of each.
These leaves agree in being netted-veined ; i.e., in having veinlets
that join each other at many angles, so as to form a sort of delicate
lace-work, like Figs. 94 and 95.

They differ, however, in the arrangement of the principal veins. Such

a leaf as that of the elm is said to be feather-veined, orpinnately veined.

The maple leaf, or any leaf with closely similar venation, is said to

be palmately veined. Describe the difference between the two plans

of venation.

143, Relation of Venation to Shape of Leaves. — As soon
as the student begins to observe leaves somewhat widely,

LEAVES

135

he can hardly fail to notice that there is a general relation
between the plan of venation and the shape of the leaf.
How may this relation be stated? In most cases the
principal veins follow at the outset a pretty straight
course, a fact for which the student ought to be able to
give a reason after he has performed Exp. XXXII.

On the whole, the arrangement of the
veins seems to be
such as to stiff-
en the leaf
most in the
parts that need

FIG. 97. — Palmately Divided
Leaf of Buttercup.

FIG. 98. — Leaf of Ap-
ple, with Stipules.

PIG. 99. — Leaf of
Pansy, with Leaf-
Like Stipules.

most support, and to reach the region near the margin by
as short a course as possible from the end of the petiole.

144, Stipules. — Although they are absent from many
leaves, and disappear early from others, stipules form a
part of what the botanist regards as an ideal or model
leaf.1 When present they are sometimes found as little

1 Unless the elm twigs used in the previous study were cut soon after the
unfolding of the leaves in spring, the stipules may not have been left in any
recognizable shape.

136

FOUNDATIONS OF BOTANY

PIG. 100. — Parallel-
Veined Leaf of Sol-
omon's Seal.

bristle^haped objects at the base of the leaf, as in the
apple leaf (Fig. 98), sometimes as leaf-like bodies, for
JL example in the pansy (Fig. 99), and in

y^^Wllwk many other forms, one of which is that
/«Illlllffllm of sPinous appendages, as shown in the
common locust (Fig. 103).

145. Parallel -Veined Leaves. — The
leaves of many great groups of plants,
such as the lilies, the sedges, and the
grasses, are commonly parallel-veined,
that is, with the veins running nearly
parallel, lengthwise through the blade,
as shown in Fig. 100, or
with parallel veins pro-
ceeding from a midrib and thence extend-
ing to the margin, as shown in Fig. 101.
146. Occurrence of Netted Veining and
of Parallel Veining. — The student has
already, in his experiments on germina-
tion, had an opportunity to observe the
difference in mode of veining between
the leaves of some dicotyledonous plants
and those of monocotyledonous plants.
This difference is general throughout
these great groups of flowering plants.
What is the difference?

The polycotyledonous pines, spruces, FIG. 101. — Parallel
and other coniferous trees have leaves £ffiL££££
with but a single vein, or two or three midrib to margin-
parallel ones, but in their case the veining could hardly
be other than parallel, since the needle-like leaves are so

LEAVES

13T

narrow that no veins of any considerable length could
exist except in a position lengthwise of the leaf.

The fact that a certain plan of venation is found mainly
in plants with a particular mode of germination, of stem
structure, and of arrangement of floral parts, is but one
of the frequent
cases in botany
in which the
structures of
plants are corre-
lated in a way
which it is not
easy to explain.

No one knows
why plants with
two cotyledons
should have
n e 1 1 e d- v e i n e d
leaves, but many
such facts as this
are familiar to
every botanist.

147. Simple
and Compound
•Leaves. — The
leaves so far studied are simple leaves, that is, leaves of which
the blades are more or less entirely united into one piece.
But while in the elm the margin is cut in only a little
way, in some maples it is deeply cut in toward the bases
of the veins. In some leaves the gaps between the
adjacent portions extend all the way down to the petiole

FIG. 102. — The Fall of the Horse-Chestnut Leaf.

138

FOUNDATIONS OF BOTANY

(in palmately veined leaves) or to the midrib (in pinnately
veined ones). Such divided leaves are shown in Figs.
96 and 97.

In still other leaves, known as compound leaves, the
petiole, as shown in Fig. 102 (palmately compound), or the
midrib, as shown in Fig. 103 (pin-
nately compound), bears what look to
be separate leaves. These differ in
their nature and
mode of origin
from the portions
of the blade of a
divided leaf. One
result of this dif-
ference appears in
the fact that some
time before the
whole leaf is ready
to fall from the
tree or other plant
in autumn, the
separate portions
or leaflets of a
compound leaf are
seen to be jointed-
at their attach-
ments, just as whole leaves are to the part of the stem from
which they grow. In Fig. 102 the horse-chestnut leaf is
shown at the time of falling, with some of the leaflets
already disjointed.

That a compound leaf, in spite of the joints of the

FlG. 103. — Pinnately Com-
pound Leaf of Locust,
with Spines for Stipules.

FIG. 104. — Pinnately
Compound Leaf of
Pea. A tendril takes
the place of a terminal
leaflet.

LEAVES 139

separate leaflets, is really only one leaf is shown : (1) by
the absence of buds in the axils of leaflets (see Fig. 82) ;

(2) by the arrangement of the blades of the leaflets hori-
zontally, without any twist in their individual leaf-stalks ;

(3) by the fact that their arrangement on the midrib does
not follow any of the systems of leaf arrangement on the
stem (Sect. 149). If each leaflet of a compound leaf should
itself become compound, the result would be to produce
a twice compound leaf. Fig. 113 shows that of an acacia.
What would be the appearance of a thrice compound leaf?

148, Review Summary of Leaves.1

f1-

Parts of a model leaf ... . Jo

Classes of netted-veined leaves

Classes of parallel-veined leaves

Relation of venation to number of cotyledons . . . . J

Compound leaves ; — types, dependent on arrangement of II.
leaflets | 2.

Once, twice, or three times compound ....
1 Illustrate by sketches if possible.

CHAPTER X

LEAF ARRANGEMENT FOR EXPOSURE TO SUN AND AIR;
MOVEMENTS OF LEAVES AND SHOOTS

149. Leaf Arrangement.1 — As has been learned from
the study of the leafy twigs examined, leaves are quite

generally arranged so as to
secure the best possible ex-
posure to the sun and air.
This, in the vertical shoots
of the elm, the oak (Fig. 105),
^e aPPle> beech, and other
alternate-leaved trees, is not
inconsistent with their spiral
arrangement of the leaves

FIG. 105. — Leaf Arrangement
of the Oak.

around the stem. In horizon-
tal twigs and branches of the
elm, the beech (Fig. 106),
the chestnut, the linden, and
many other trees and shrubs,
the desired effect is secured
by the arrangement of all the
leaves in two flat rows, one on each side of the twig.

FIG. 106. — Leaf Arrangement of
European Beech.

1 See Kerner and Oliver's Natural History of Plants, Vol. I, pp. 396-424.

140

PLATE III. — Exposure to Sunlight, Japanese Ivy

LEAF EXPOSURE TO SUN AND AIR

141

FIG. 107.— Leaf Arrangement of Horse-Chestnut on
Vertical Shoots (top view).

The rows are produced, as it is easy to see on examining
such a leafy twig, by a twisting about of the petioles.

The adjustment
A

<mjj, in many opposite-

leaved trees and
shrubs consists in
having each pair
of leaves cover
the spaces be-
tween the pair
below it, and
sometimes in the
lengthening of
the lower petioles
so as to bring
the blades of
the lower leaves outside those of the upper leaves. Ex-
amination of Figs. 107 and 108 will make the matter
clear.

The student
should not fail to
study the leafage
of several trees of
different kinds on
the growing tree
itself, and in
climbers on walls
(Plate III), and to
notice how circum-
stances modify the position of the leaves. Maple leaves, for
example, on the ends of the branches are arranged much

FIG. 108.— Leaf Arrangement of Horse-Chestnut
on Vertical Shoots (side view).

142

FOUNDATIONS OF BOTANY

like those of the horse-chestnut, but they are found to be
arranged more nearly flatwise along the inner portions
of the branches, that is, the portions nearer the tree.
Figs. 109 and 110 show the remarkable difference in
arrangement in different branches of the Deutzia, and
equally interesting modifications may be found in
alternate-leaved trees, such as the elm and the cherry.

FIG. 109. — Opposite Leaves of Deutzia1 (from the same shrub as Pig. 110), as
arranged on a Horizontal Branch.

150, Leaf-Mosaics. — In very many cases the leaves at
the end of a shoot are so arranged as to form a pretty
symmetrical pattern, as in the horse-chestnut (Fig. 107).
When this is sufficiently regular, usually with the spa'ce
between the leaves a good deal smaller than the areas of
the leaves themselves, it is called a leaf-mosaic (Fig. 111).
Many of the most interesting leaf-groups of this sort (as

1 Deutzia crenata.

LEAF EXPOSURE TO SUN AND AIR

143

FIG. 110. — Opposite Leaves of Deutzia, as
arranged on a Vertical Branch.

in the figure above mentioned) are found in the so-called
root-leaves of plants. Good examples of these are the

dandelion, chicory, fall
dandelion, thistle, hawk-
weed, pyrola, plantain.
How are the leaves of
these plants kept from
shading each other?

151. Much-Divided
Leaves. — Not infre-
quently leaves are cut
into slender fringe - like
divisions, as in the carrot,
tansy, southernwood,
wormwood, yarrow, dog-
fennel, cypress-vine, and many other common plants. This
kind of leaf seems to be adapted to offer considerable
surface to the sun without cut-
ting off too much light from

other leaves underneath. Such

•

a leaf is in much less danger of
being torn by severe winds than
are broader ones with undivided
margins. The same purposes
are served by compound leaves
with very many small leaflets,
such as those of the honey-
locust, mimosa acacia (Fig. 113),
and other trees and shrubs of the pea family. What kind
of shade is produced by a horse-chestnut or a maple tree
compared with that of a honey-locust or an acacia ?

FIG. 111. —Leaf -Mosaic of a .
Campanula.

144 FOUNDATIONS OF BOTANY

152. Daily Movements of Leaves. — Many compound
leaves have the power of changing the position of their
leaflets to accommodate themselves to varying conditions
of light and temperature. Some plants have the power
of directing the leaves or leaflets edgewise towards the
sun during the hottest parts of the day, allowing them to

extend their surfaces
more nearly in a hori-
zontal direction during
the cooler hours.

The so-called "sleep"
of plants has long been
known, but this subject

FIG. 112. — A Leaf of Red Clover. J

At the left, leaf by day; at the right, the same has been HlOSt Carefully

leaf asleep at night. studied rather recently.

The wood sorrel, or oxalis, the common bean, clovers,
and the locust tree are some of the most familiar of
the plants whose leaves assume decidedly different posi-
tions at night from those which they occupy during the
day. Sometimes the leaflets rise at night, and in many
instances they droop, as in the red clover (Fig. 112) and
the acacia (Fig. 113). One useful purpose, at any rate,
that is served by the leafs taking the nocturnal position is
protection from frost. It has been proved experimentally
that when part of the leaves on a plant are prevented from
assuming the folded position, while others are allowed to
do so, and the plant is then exposed during a frosty night,
the folded ones may escape while the others are killed.
Since many plants in tropical climates fold their leaves
at night, it is certain that this movement has other pur-
poses than protection from frost, and probably there is

LEAF EXPOSURE TO SUN AND AIR

145

much yet to be learned about the meaning and importance
of leaf-movements.

153. Cause of Sleep-Movements. — The student may
very naturally inquire whether the change to the noc-
turnal position is brought about by the change from light
to darkness or whether it depends rather upon the time
of day. It will be interesting to try an experiment in
regard to this.

EXPERIMENT XXYI

Remove a pot containing an oxalis from a sunny window to a
dark closet, at about the same temperature, and note at intervals of
five minutes the condition of its leaves for half an hour or more.

FIG. 113. — A Leaf of Acacia.
A, as seen by day ; JB, the same leaf asleep at night.

154. Structure of the Parts which cause Leaf -Motions. —
In a great number of cases the daily movements of leaves
are produced by special organs at the bases of the leaf-
stalks. These cushion-like organs, called pulvini (Fig.
114), are composed mainly of parenchyinatous tissue

146

FOUNDATIONS OF BOTANY

(Sect. 106), which contains much water. It is impossible
fully to explain in simple language the way in which the
cells of the pulvini act, but in a general way it may be
said that changes in the light to which the plant is exposed
cause rather prompt changes in the amount of water in

the cells in one portion or
other of the pulvinus. If the
cells on one side are filled
fuller of water than usual,
that side of the pulvinus will
be expanded and make the
leaf-stalk bend toward the
opposite side. The prompt-
ness of these
movements is no
doubt in consid-
erable measure

FIG. 114. — Compound Leaf of Bean with '^'J due to the fact

Pulvinus. (The pulvinus shows as an || | . . , ..

enlargement, in the figure about three- that in the pul-

eighths inch long, at the base of the yini /^ in many

petiole.) J

other parts of

plants) the protoplasm of adjacent cells is connected.
Delicate threads of protoplasm extend through the cell-
walls, making the whole tissue a living web, so that any
suitable stimulus or excitant which acts on one part of
the organ will soon affect the whole organ.

155. Vertically Placed Leaves. — Very many leaves, like
those of the iris (Fig. 44), always keep their principal sur-
faces nearly vertical, thus receiving the morning and even-
ing sun upon their faces, and the noonday sun (which is
so intense as to injure them when received full on the

LEAF EXPOSURE TO SUN AND AIR

147

surface) upon their edges. This adjustment is most per-
fect in the compass-plant of the prairies of the Mississippi
basin. Its leaves stand very nearly upright, many with

A B

FIG. 115. —Leaves standing nearly Vertical in Compass-Plant (Silphium laciniatum).
A, view from east or west ; £, from north or south.

their edges just about north and south (Fig. 115), so that
the rays of the midsummer sun will, during every bright

148 FOUNDATIONS OF BOTANY

day, strike the leaf-surfaces nearly at right angles during
a considerable portion of the forenoon and afternoon,
while at midday only the edge of each leaf is exposed
to the sun.

156. Movements of Leaves and Stems toward or away
from Light (Heliotropic Movements). — The student doubt-
less learned from his experiments with seedling plants
that their stems tend to seek light. The whole plant
above ground usually bends toward the quarter from which
the strongest light comes. Such movements are called
Tieliotropic from two Greek words which mean turning
toward the sun. How do the plants in a window behave
with reference to the light ?

EXPERIMENT XXVII

How do Young Shoots of English Ivy bend with Reference to Light ?
— Place a thrifty potted plant of English ivy before a small window,
e.g., an ordinary cellar window, or in a large covered box, painted dull
black within and open only on the side toward a south window.
After some weeks note the position of the tips of the shoots.
Explain the use of their movements to the plant.

157. Positive and Negative Heliotropic Movements ; how
produced. — Plants may bend either toward or away from
the strongest light. In the former case they are said to
show positive heliotropism, in the latter negative heliotro-
pism. In both cases the movement is produced by unequal
growth, brought about by the unequal lighting of different
sides of the stem. If the less strongly lighted side grows
faster, what kind of heliotropism results? If the more
strongly lighted side grows faster, what kind of heliotro-
pism results ? How would a plant behave if placed on a

LEAF EXPOSURE TO SUN AND AIR 149

revolving table before a window and slowly turned during
the hours of daylight?

158. Review Summary of Chapter X.

f For vertical twigs
Leaf arrangement . . . <*_ . . J _ , .

L r or horizontal twigs

f Apparatus for

Movements of leaves . . « Causes of

[ Uses of

Compass-plants ....

TT ,.,.,,. f Positive

Heliotropic bending of stems <

CHAPTER XI

MINUTE STRUCTURE OF LEAVES; FUNCTIONS OF
LEAVES

159. Leaf of Lily. — A good kind of leaf with which
to begin the study of the microscopical structure of leaves
in general is that of the lily.1

160. Cross-Section of Lily Leaf. — The student should first exam-
ine with the microscope a cross-section of the leaf, that is, a very
thin slice, taken at right angles to the upper and under surfaces and
to the veins. This will show :

(a) The upper epidermis of the leaf, a thin, nearly transparent
membrane.

(6) The intermediate tissues.

Use a power of from 100 to 200 diameters. In order to ascertain
the relations of the parts, and to get their names, consult Fig. 116.
Your section is by no means exactly like the figure ; sketch it. Label
properly all the parts shown in your sketch.

Are any differences noticeable between the upper and the lower
epidermis? Between the layers of cells immediately adjacent to
each?

161. Under Surface of Lily Leaf. — Examine with a power of 200
or more diameters the outer surface of a piece of epidermis from the
lower side of the leaf.2 Sketch carefully, comparing your sketch
with Figs. 117 and 118, and labeling it to agree with those figures.

Examine another piece from the upper surface ; sketch it.
How does the number of stomata in the two cases compare ?

1 Any kind of lily will answer.

2 The epidermis may be started with a sharp knife, then peeled off with
small forceps, and mounted in water for microscopical examination.

150

MINUTE STRUCTURE OF LEAVES

151

Take measurements from the last three sketches with a scale and,
knowing what magnifying power was used, answer these questions l :
(a) How thick is the epidermis ?

(&) What is the length and the breadth of the epidermal cells ?
(c) What is the average size of the pulp-cells ?

A stoma is a microscopic pore or slit in the epidermis.
It is bounded and opened and shut by guard-cells (Fig.
118, #), usually two in number. These are generally

FIG. 116. — Vertical Section of the Leaf of the Beet. (Much magnified.)

e, epidermis ; p, palisade-cells' (and similar elongated cells) ; r, cells filled with
red cell sap ; i, intercellular spaces ; a, air spaces communicating with the
stomata ; st, stomata, or hreathing pores.

1 The teacher may measure the size with the camera lucida.

152

FOUNDATIONS OF BOTANY

P- —

p —

somewhat kidney-shaped and become more or less curved
as they are fuller or less full of water (see Sect. 170).

162. Calculation of Number of Stomata per Unit of Area.
— In order to get a fairly exact idea of the number of
stomata on a unit of leaf-surface, the most convenient

plan is to make
use of a photo-
micrograph. The
bromide enlarge-
ment No. 12 of
the Tower series
represents about
a twenty-five-
hundredth of a
square inch of the
lower epidermis of
the cyclamen leaf,
magnified until it
is about fifteen
inches square.
Count the number
of stomata on the
entire photograph,
then calculate the
number of stomata
on a square inch
of the surface of

FIG. 117. —Epidermis of Leaf of Althaea.

(Much magnified.)

A, from upper surface ; B, from lower surface.
h, star-shaped compound hairs ; st, stomata ; p,
upper ends of palisade-cells, seen through the
epidermis ; e, cells of epidermis.

this leaf. If a cyclamen plant has twelve leaves, each
with an average area of six square inches, calculate the
number of stomata of the lower epidermis of all the leaves
taken together.

MINUTE STRUCTURE OF LEAVES

153

In the case of an apple tree, where the epidermis of the
lower surface of the leaf contains about 24,000 stomata to
the square inch, or the black walnut, with nearly 300,000
to the square inch,
the total number
on a tree is incon-
ceivably large.

163. Uses of the
Parts examined. —
It will be most con-
venient to discuss
the uses of the
parts of the leaf a
little later, but it
will make matters
simpler to state at
once that the epi-
dermis serves as a
mechanical protec-
tion to the parts
beneath and pre-
vents excessive
evaporation, that
the palisade-cells
(which it may not be easy to make out very clearly in a
roughly prepared section) hold large quantities of the green
coloring matter of the leaf in a position where it can
receive enough but not too much sunlight, and the cells
of the spongy parenchyma share the work of the palisade-
cells, besides evaporating much water. The stomata
admit air to the interior of the leaf (where the air spaces

FIG. 118. —A Stoma of Thyme. (Greatly magnified.)

A, section at right angles to surface of leaf ; S, sur-
face view of stoma. cu, cuticle ; g, guard-cells ;
s, stoma ; e, epidermal cells ; a, air chamber ;
c, cells of spongy parenchyma with grains of
chlorophyll.

154

FOUNDATIONS OF BOTANY

serve to store and to distribute it), they allow oxygen
and carbonic acid gas to escape, and, above all, they regu-
late the evaporation of water from the plant.

164. Leaf of "India-Rubber Plant." l — Study with the micro-
scope, as the lily leaf was studied, make the same set of sketches,
note the differences in structure between the two leaves, and try to
discover their meaning.

How does the epidermis of the two leaves compare ?

Which has the larger stomata?

Which would better withstand great heat and long drought ?

165. Chlorophyll as found in the Leaf. — Slice off a
little of the epidermis from some such soft, pulpy leaf as

FIG. 119. — Section through Lower Epidermis of Leaf of India-Rubber Plant

(Ficus elastica). (Magnified 330 diameters.)

o, opening of pit ; p, pit leading to stoma ; s, stoma, with two guard-cells ; w,
water-storage cells of epidermis ; a, an air space ; around and above the air
spaces are cells of the spongy parenchyma.

that of the common field sorrel,2 live-for-ever, or spinach ;
scrape from the exposed portion a very little of the green
pulp ; examine with the highest power attainable with
your microscope, and sketch several cells.

1 Ficus elastica, a kind of fig tree.

2 Rumex Acetosella.

MINUTE STRUCTURE OF LEAVES

155

Notice that the green coloring matter is not uniformly
distributed, but that it is collected into little particles
called chlorophyll bodies (Fig. 120, p).

166. Woody Tissue in Leaves. — The veins of leaves
consist of fibre-vascular bundles containing wood and
vessels much like those of the stem
of the plant. Indeed, these bundles
in the leaf are continuous with those
of the stem, and consist merely of
portions of the latter, looking
as if unraveled, which pass ;
outward and upward from the
stem into the leaf under
the name of leaf-traces.
These traverse the peti-
ole often in a somewhat
irregular fashion.

EXPERIMENT XXVIII
of Water from

FIG. 120. — Termination
of a Vein in a Leaf.
(Magnified about 345
diameters.)

v, spirally thickened cells

Stem to Leaf. —Place a Of the vein 5jp, paren-

freshly cut leafy shoot of some chyma-cells of the

. spongy interior of the

plant with large thin leaves, ieaf, with chlorophyll

such as Hydrangea hortensia, 1°*™*' n> nucleated

in eosin solution for a few

minutes. As soon as the leaves show a decided reddening, pull

some of them off and sketch the red stains on the scars thus made.

What does this show?

167. Experimental Study of Functions of Leaves. — The

most interesting and profitable way in which to find out
what work leaves do for the plant is by experimenting
upon them. Much ,that relates to the uses of leaves is

156 FOUNDATIONS OF BOTANY

not readily shown in ordinary class-room experiments, but
some things can readily be demonstrated in the experi-
ments which follow.

EXPERIMENT XXIX

Transpiration. — Take two twigs or leafy shoots of any thin-leafed
plant ; l cover the cut end of each stem with a bit of grafting wax 2
to prevent evaporation from the cut surface. Put one shoot into a
fruit jar, screw the top on, and leave in a warm room; put the other
beside it, and allow both to remain some hours. Examine the
relative appearance of the two, as regards wilting, at the end of the
time.

Which shoot has lost most ? Why ? Has the one in the fruit
jar lost any water ? To answer this question, put the jar (without
opening it) into a refrigerator ; or, if the weather is cold, put it out
of doors for a few minutes, and examine the appearance of the inside
of the jar. What does this show ? 3

168. Uses of the Epidermis.4 — The epidermis, by its
toughness, tends to prevent mechanical injuries to the
leaf, and after the filling up of a part of its outer por-
tion with a corky substance it greatly diminishes the loss of
water from the general surface. This process of becom-
ing filled with cork (or a substance of similar properties
known as cutiri) is absolutely essential to the safety of
leaves or young portions of stems which have to with-
stand heat and dryness. The corky or cutinized cell-
wall is waterproof, while ordinary cellulose allows water

1 Hydrangea, squash, melon, or cucumber is best; many other kinds will
answer very well.

2 Grafting wax may be bought of nurserymen or seedsmen.

3 If the student is in doubt whether the jar filled with ordinary air might
not behave in the same way, the question may be readily answered by putting
a sealed jar of air into the refrigerator.

* See Kerner and Oliver's Natural History of Plants, Vol. I, pp. 273-362.

MINUTE STRUCTURE OF LEAVES

157

to soak through it with ease. Merely examining sections
of the various kinds of epidermis will not give nearly
as good an idea of their properties as can be obtained
by studying the behavior during severe droughts of
plants which have strongly cutinized surfaces and of
those which have not. Fig. 121, however, may convey
some notion of the difference between the two kinds of
structure. In most
cases, as in the india-
rubber tree, the ex-
ternal epidermal cells
(and often two or
three layers of cells
beneath these) are
filled with water, and
thus serve as reser-
voirs from which the
outer parts of the leaf
and the stem are at
times supplied.

In many cases, noticeably in the cabbage, the epidermis
is covered with a waxy coating, which doubtless increases
the power of' the leaf to retain needed moisture, and
which certainly prevents rain or dew from covering the
leaf-surfaces, especially the lower surfaces, so as to hinder
the operation of the stomata. Many common plants, like
the meadow rue and the nasturtium, possess this power
to shed water to such a degree that the under surface of
the leaf is hardly wet at all when immersed in water.
The air-bubbles on such leaves give them a silvery
appearance when held under water.

FIG. 121. — Unequal Development of Cuticle

by Epidermis-Cells.

A, epidermis of Butcher's Broom (Ruscus) ; B,
epidermis of sunflower ; c, cuticle ; e, epi-
dermis-cells.

158 FOUNDATIONS OF BOTANY

169. Hairs on Leaves. — Many kinds of leaves are more
or less hairy or downy, as those of the mullein, the
"mullein pink," many cinquefoils, and other common
plants. In some instances this hairiness may be a protec-
tion against snails or other small leaf-eating animals, but
in other cases it seems to be pretty clear that the woolli-
ness (so often confined to the under surface) is to lessen
the loss of water through the stomata. The Labrador
tea is an excellent example of a plant, with a densely
woolly coating on the lower surface of the leaf. The
leaves, too, are partly rolled up (see Fig. 224), with the
upper surface outward, so as to give the lower surface
a sort of deeply grooved form, and on the lower surface
all of the stomata are placed. This plant, like some
others with the same characteristics, ranges far north into
regions where the temperature, even during summer,
often falls so low that absorption of water by the roots
ceases, since it has been shown that this nearly stops a
little above the freezing point of water (see Exp. XVII).
Exposed to cold, dry winds, the plant would then often
be killed by complete drying if it were not for the pro-
tection afforded by the woolly, channeled under surfaces
of the leaves.1

170. Operation of the Stomata. — The stomata serve to
admit air to the interior of the leaf, and to allow moisture,
in the form of vapor, to pass out of it. They do this not
in a passive way, as so many mere holes in the epidermis
might, but to a considerable extent they regulate the
rapidity of transpiration, opening more widely in damp
weather and closing in dry weather. The opening is

1 This adaptation is sufficiently interesting for class study.

PLATE IV. — A Cypress Swamp

MINUTE STRUCTURE OF LEAVES 159

caused by each of the guard-cells bending into a more
kidnejr-like form than usual, and the closing by a straight-
ening out of the guard-cells. The under side of the leaf,
free from palisade-cells, abounding in intercellular spaces,
and pretty well protected from becoming covered with
rain or dew, is especially adapted for the working of the
stomata, and accordingly we usually find them in much
greater numbers on the lower surface. On the other
hand, the little flowerless plants known as liverworts,
which lie prostrate on the ground, have their stomata on
the upper surface, and so do the leaves of pond lilies,
which lie flat on the water. In those leaves which stand
with their edges nearly vertical, the stomata are dis-
tributed somewhat equally on both surfaces. Stomata
occur in the epidermis of young stems, being replaced
later by the lenticels. Those plants which, like the (
cacti, have no ordinary leaves, transpire through the
stomata scattered over their general surfaces.

The health of the plant depends largely on the proper
working condition of the stomata, and one reason why
plants in cities often fail to thrive is that the stomata
become choked with dust and soot. In some plants, as
the oleander, provision is made for the exclusion of dust
by a fringe of hairs about the opening of each stoma. If
the stomata were to become filled with water, their activ-
ity would cease until they were freed from it; hence
many plants have their leaves, especially the under sur-
faces, protected by a coating of wax which sheds water.

171. Measurement of Transpiration. — We have already
proved that water is lost by the leaves, but it is worth
while to perform a careful experiment to reduce our

160

FOUNDATIONS OF BOTANY

knowledge to an exact form, to learn how much water
a given plant transpires under certain conditions. It is
also desirable to find out whether different kinds of plants
transpire alike, and what changes in the temperature, the
dampness of the air, the brightness of the light, to which
a plant is exposed, have to do with its transpiration.
Another experiment will show whether both sides of a
leaf transpire alike.

EXPERIMENT XXX

Amount of Water lost by Transpiration. — Procure a thrifty hydran-
gea1 and a small "india-rubber plant,"2 each growing in a small

flower-pot, and with the number
of square inches of leaf-surface
in the two plants not too widely
different. Calculate the area of
the leaf-surface for each plant,
by dividing the surface of a piece
of tracing cloth into a series of
squares one-half inch on a side,
holding an average leaf of each
plant against this and counting
the number of squares and parts
of squares covered by the leaf.
Or weigh a square inch of tinfoil
on a very delicate balance, cut
out a piece of the same kind of
tinfoil of the size of an average
leaf, weigh this and calculate the
leaf -area from the two weights.
This area, multiplied by the number of leaves for each plant, will
give approximately the total evaporating surface for each.

Transfer each plant to a glass battery jar of suitable size. Cover

FIG. 122. — A Hydrangea potted in a
Battery Jar for Exp. XXX.

1 The common species of the greenhouses, Hydrangea hortensia.

2 This is really a fig, Ficus elastica.

MINUTE STRUCTURE OF LEAVES 161

the jar with a piece of sheet lead, slit to admit the stem of the plant,
invert the jar and seal the lead to the glass with a hot mixture of
beeswax and rosin. Seal up the slit and the opening about the
stem with grafting wax. A thistle-tube, such as is used by chem-
ists, is also to be inserted, as shown in Fig. 122.1 The mouth of this
may be kept corked when the tube is not in use for watering.

Water each plant moderately and weigh the plants separately on
a balance that is sensitive to one or two grams. Record the weights,
allow the plants to stand in a sunny, warm room for twenty-four
hours and reweigh.

Add to each plant just the amount of water which is lost,2 and
continue the experiment in the same manner for several days so as
to ascertain, if possible, the effect upon transpiration of varyi rig-
amounts of water in the atmosphere.

Calculate the average loss per 100 square inches of leaf-surface for
each plant throughout the whole course of the experiment. Divide
the greater loss by the lesser to find their ratio. Find the ratio of
each plant's greatest loss per day to its least loss per day, and by
comparing these ratios decide which transpires more regularly.

Try the effect of supplying very little water to each, so that the
hydrangea will begin to droop, and see whether this changes the
relative amount of transpiration for the two plants. Vary the con-
ditions of the experiment for a day or two as regards temperature,
and again for a day or two as regards light, and note the effect upon
the amount of transpiration.

The structure of the fig (India-rubber plant) leaf has already been
studied. That of the hydrangea is looser in texture and more like
the leaf of the lily or the beet (Fig. 116).

What light does the structure throw on the results of the pre-
ceding experiment ?

1 It will be much more convenient to tie the hydrangea if one has been
chosen that has but a single main stem. Instead of the hydrangea, the com-
mon cineraria, Senecio cruentus, does very well.

2 The addition of known amounts of water may be made most conveniently
by measuring it in a cylindrical graduate.

162 FOUNDATIONS OF BOTANY

EXPERIMENT XXXI

Through which Side of a Leaf of the India-Rubber Plant does Tran-
spiration occur? — The student may already have found (Sect. 164)
that there are no stomata on the upper surface of the fig leaf which
he studied. That fact makes this leaf an excellent one by means of
which to study the relation of stomata to transpiration.

Take two large, sound rubber-plant leaves, cut off pretty close to
the stem of the plant. Slip over the cut end of the petiole of each
leaf a piece of small rubber tubing, wire this on, leaving about half
of it free, then double the free end over and wire tightly, so as to
make the covering moisture-proof. Warm some vaseline or grafting
wax until it is almost liquid, and spread a thin layer of it smoothly
over the upper surface of one leaf and the lower surface of the other.
Hang both up in a sunny place in the laboratory and watch them for
a month or more.

What difference in the appearance of the two leaves becomes
evident ? What does the experiment prove ?

172. Endurance of Drought by Plants. — Plants in a wild
state have to live under extremely different conditions as
regards water supply (see Chapter XXIV). Observation
of growing plants during a long drought will quickly
show how differently the various species of a region bear
the hardships due to a scanty supply of moisture. It is
still easier, however, to subject some plants to an artificial
drought and watch their condition.

EXPERIMENT XXXII

Resistance to Drought. — Procure at least one plant from each of
these groups :

Group I. Melon-cactus (Echinocactus or Mamillaria), prickly
pear cactus.

Group II. Aloe, Cotyledon (often called Echeveria), houseleek.

MINUTE STRUCTURE OF LEAVES 163

Group III. Live-for-ever (Sedum Telephium), Bryophyllum, English
ivy, " ivy-leafed geranium," (Pelargonium peltatum), or any of the
fleshy-leafed begonias.

Group IV. Hydrangea (H. hortensia), squash or cucumber, sun-
flower.

The plants should be growing in pots and well rooted. Water
them well and then put them all in a warm, sunny place. Note the
appearance of all the plants at the end of twenty-four hours. If any
are wilting badly, water them. Keep on with the experiment, in no
case watering any plant or set of plants until it has wilted a good
deal. Record the observations in such a way as to show just how
long a time it took each plant to begin to wilt from the time when
the experiment began. If any hold out more than a month, they
may afterwards be examined at intervals of a week, to save the time
required for daily observations. If possible, account by the struc-
ture of the plants for some of the differences observed. Try to learn
the native country of each plant used and the soil or exposure natural
to it.

173, Course traversed by Water through the Leaf. — The
same plan that was adopted to trace the course of water in
the stem (Exp. XXI) may be followed to discover its path
through the leaf.

EXPERIMENT XXXIII

Rise of Sap in Leaves. — Put the freshly cut ends of the petioles
of several thin leaves of different kinds into small glasses, each con-
taining eosin solution to the depth of one-quarter inch or more.
Allow them to stand for half an hour, and examine them by holding
up to the light and looking through them to see into what parts the
eosin solution has risen. Allow some of the leaves to remain as
much as twelve hours, and examine them again. The red-stained
portions of the leaf mark the lines along which, under natural con-
ditions, sap rises into it. Cut across (near the petiole or midrib
ends) all the principal veins of some kind of large, thin leaf. Then
cut off the petiole and at once stand the cut end, to which the blade

164 FOUNDATIONS OF BOTANY

is attached, in eosin solution. Repeat with another leaf and stand
in water. What do the results teach ?

174. Total Amount of Transpiration. — In order to pre-
vent wilting, the rise of sap during the life of the leaf
must have kept pace with the evaporation from its sur-
face. The total amount of water that travels through the
roots, stems, and leaves of most seed-plants during their
lifetime is large, relative to the weight of the plant itself.
During 173 days of growth a corn-plant has been found to
give off nearly 31 pounds of water. During 140 days of
growth a sunflower-plant gave off about 145 pounds. A
grass-plant has been found to give off its own weight of
water every twenty-four hours in hot, dry summer weather.
This would make about 6 ^ tons per acre every twenty-four
hours for an ordinary grass-field, or rather over 2200 pounds
of water from a field 50 X 150 feet, that is, not larger than
a good-sized city lot. Calculations based on observations
made by the Austrian forest experiment stations showed
that a birch tree with 200,000 leaves, standing in open
ground, transpired on hot summer days from 700 to 900
pounds, while at other times the amount of transpiration
was probably not more than 18 to 20 pounds.1

These large amounts of water are absorbed, carried
through the tissues of the plant, and then given off by the
leaves simply because the plant-food contained in the soil-
water is in a condition so diluted that great quantities of
water must be taken in order to secure enough of the min-
eral and other substances which the plant demands from
the soil.

1 See B. E. Fernow's discussion in Report of Division of Forestry of U. S.
Department of Agriculture, 1889.

MINUTE STRUCTURE OF LEAVES 165

Meadow hay contains about two per cent of potash, or
2000 parts in 100,000, while the soil- water of a good soil
does not contain more than one-half part in 100,000 parts.
It would therefore take 4000 tons of such water to furnish
the potash for one ton of hay. The water which the
root-hairs take up must, however, contain far more potash
than is assumed in the calculation above given, so that the
amount of water actually used in the growth of a ton of
hay cannot be much more than 260 tons.1

175. Accumulation of Mineral Matter in the Leaf. — Just
as a deposit of salt is found in the bottom of a seaside pool
of salt water which has been dried up by the sun, so old
leaves are found to be loaded with mineral matter, left
behind as the sap drawn up from the roots is evaporated
through the stomata. A bonfire of leaves makes a sur-
prisingly large heap of ashes. An abundant constituent
of the ashes of burnt leaves is silica, a substance chemic-
ally the same as sand. This the plant is forced to absorb
along with the potash, compounds of phosphorus, and other
useful substances contained in the soil-water; but since
the silica is of hardly any value to most plants, it often
accumulates in the leaf as so much refuse. Lime is much
more useful to the plant than silica, but a far larger quan-
tity of it is absorbed than is needed; hence it, too, accu-
mulates in the leaf.

176. Nutrition, Metabolism.2 — The manufacture of the
more complex plant-foods, starch, sugar, and so on, from

1 See the article, " Water as a Factor in the Growth of Plants," by B. T.
Galloway and Albert F. Woods, Year-Book of U. S. Department of Agriculture,
1894.

2 See Kerner and Oliver's Natural History of Plants, Vol. I, pp. 371-483.
Also Pfeffer's Physiology of Plants, translated by Ewart, Chapter VIII.

166 FOUNDATIONS OF BOTANY

the raw materials which are afforded by the earth and air
and all the steps of the processes by which these foods are
used in the life and growth of the plant are together known
as its nutrition. When we think more of the chemical
side of nutrition than of its relation to plant-life, we call
any of the changes or all of them metabolism, which means
simply chemical transformation in living tissues. There
are two main classes of metabolism — the constructive kind,
which embraces those changes which build up more com-
plicated substances out of simpler ones (Sect. 179), and the
destructive kind, the reverse of the former (Sect. 184). A
good many references to cases of plant metabolism have
been made in earlier chapters, but the subject comes up in
more detail in connection with the study of the work of leaves
than anywhere else, because the feeding which the ordinary
seed-plant does is very largely done in and by its leaves.

177. Details of the Work of the Leaf. — A leaf has four
functions to perform : (1) Starch-making ; (2) assimila-
tion ; * (3) excretion of water ; (4) respiration.

178. Absorption of Carbon Dioxide and Removal of its
Carbon. — Carbon dioxide is a constant ingredient of the
atmosphere, usually occurring in the proportion of about
four parts in every 10,000 of air or one twenty-fifth of one
per cent. It is a colorless gas, a compound of two simple
substances or elements, carbon and oxygen, the former
familiar to us in the forms of charcoal and graphite, the
latter occurring as the active constituent of air.

1 In many works on Botany (1) and (2) are both compounded under the
term assimilation. Many botanists (most of the American ones) apply the
name photosynthesis or photosyntax to the starch-making process, but these
names are not wholly satisfactory, and perhaps it is as well (as suggested by
Professor Atkinson) to name the process from its result.

MINUTE STRUCTURE OF LEAVES 167

Carbon dioxide is produced in immense quantities by
the decay of vegetable and animal matter, by the respira-
tion of animals, and by all fires in which wood, coal, gas,
or petroleum is burned.

Green leaves and the green parts of plants, when they
contain a suitable amount of potassium salts, have the
power of removing carbon dioxide from the air (or in
the case of some aquatic plants from water in which it is
dissolved), retaining its carbon and setting free part or all
of the oxygen. This process is an important part of the
work done by the plant in making over raw materials into
food from which it forms its own substance.

EXPERIMENT XXXIV

Oxygen-Making in Sunlight. — Place a green aquatic plant in a
glass jar full of ice-cold fresh water, in front of a sunny window.1
Place a thermometer in the jar, watch the rise of temperature, and
note at what point you first observe the formation of oxygen bub-
bles. Remove to a dark closet for a few minutes and examine by
lamplight, to see whether the rise of bubbles still continues.

This gas may be shown to be oxygen by collecting some
of it in a small inverted test-tube filled with water and
thrusting the glowing coal of a match just blown out into
the gas. It is not, however, very easy to do this satisfac-
torily before the class.

Repeat the experiment, using water which has been well boiled
and then quickly cooled. Boiling removes all the dissolved gases
from water, and they are not re-dissolved in any considerable quantity
for many hours.

1 Elodea, Myriophyllum, Chrysosplenium, Potamogeton, Fontinalis, any of
the green aquatic flowering plants, or even the common confervaceous plants,
known as pond-scum or " frog-spit," will do for this experiment.

168 FOUNDATIONS OF BOTANY

Ordinary air, containing a known per cent of carbon dioxide,
if passed very slowly over the foliage of a plant covered with a bell-
glass and placed in full sunlight, will, if tested chemically, on com-
ing out of the bell-glass be found to have lost a little of its carbon
dioxide. The pot in which the plant grows must be covered with a
lid, closely sealed on, to prevent air charged with carbon dioxide (as
the air of the soil is apt to be) from rising into the bell-glass.

179. Disposition made of the Absorbed Carbon Dioxide.
— It would lead the student too far into the chemistry of
botany to ask him to follow out in detail the changes by
which carbon dioxide lets go part at least of its oxygen
and gives its remaining portions, namely, the carbon, and
perhaps part of its oxygen, to build up the substance of
the plant. Starch is composed of three elements : hydro-
gen (a colorless, inflammable gas, the lightest of known
substances), carbon, and oxygen. Water is composed
largely of hydrogen, and, therefore, carbon dioxide and
water contain all the elements necessary for making starch.
The chemist cannot put these elements together to form
starch, but the plant can do it, and at suitable temperatures
starch-making goes on constantly in the green parts of
plants when exposed to sunlight and supplied with water
and carbon dioxide.1 The seat of the manufacture is in
the chlorophyll bodies, and protoplasm is without doubt the
manufacturer, but the process is not understood by chemists
or botanists. No carbon dioxide can be taken up and used
by plants growing in the dark, nor in an atmosphere con-
taining only carbon dioxide, even in the light.

1 Very likely the plant makes sugar first of all and then rapidly changes
this into starch. However that may be, the first kind of food made in the
leaf and retained long enough to be found there by ordinary tests is starch.
See Pfeffer's Phi/siology of Plants, translated by Ewart, Vol. I, pp. 317, 318.

PLATE V. — A Saprophyte, Indian Pipe

MINUTE STRUCTURE OF LEAVES 169

A very good comparison of the leaf to a mill has been
made as follows l :

The mill : Palisade-cells and underlying

cells of the leaf.

Raw material used : Carbon dioxide, water.

Milling apparatus : Chlorophyll grains.
Energy by which the mill

is run : Sunlight.

Manufactured product : Starch.

Waste product : Oxygen.

180. Plants Destitute of Chlorophyll not Starch-Makers.

— Aside from the fact that newly formed starch grains are
first found in the chlorophyll bodies of the leaf and the
green layer of the bark, one of the best evidences of
the intimate relation of chlorophyll to starch-making is
derived from the fact that plants which contain no chloro-
phyll cannot make starch from water and carbon dioxide.
Parasites, like the dodder, which are nearly destitute of
green coloring matter, cannot do this; neither can sapro-
phytes or plants which live on decaying or fermenting
organic matter, animal or vegetable. Most saprophytes,
like the moulds, toadstools, and yeast, are flowerless plants
of low organization, but there are a few (such as the
Indian pipe (Plate V), which flourishes on rotten wood
or among decaying leaves) that bear flowers and seeds.

181. Detection of Starch in Leaves. — Starch may be
found in abundance by microscopical examination of the
green parts of growing leaves, or its presence may be
shown by testing the whole leaf with iodine solution.

1 By Professor George I,. Goodale.

170

FOUNDATIONS OF BOTANY

EXPERIMENT XXXV

Occurrence of Starch in Nasturtium Leaves. — Toward the close of
a veiy sunny day collect some bean leaves or leaves of nasturtium
(Tropwolum). Boil these in water for a few minutes, to kill the
protoplasmic contents of the cells and to soften and swell the starch
grains.1

Soak the leaves, after boiling, in strong alcohol for a day or two,
to dissolve out the chlorophyll, which would otherwise make it diffi-
cult to see the blue color of the starch test, if any were obtained.
Rinse out the alcohol with plenty of water
and then place the leaves for ten or fifteen
minutes in a solution of iodine, rinse off
with water and note what portions of the
leaf, if any, show the presence of starch.

EXPERIMENT XXXYI

Consumption of Starch in Nasturtium
(Tropceolum) Leaves. — Select some healthy
leaves of Tropaeolum on a plant growing
vigorously indoors or, still better, in the
open air. Shut off the sunlight from
parts of the selected leaves (which are to
be left on the plant and as little injured
as may be) by pinning circular disks of cork on opposite sides of
the leaf, as shown in Fig. 123. On the afternoon of the next day
remove these leaves from the plant and treat as described in the
preceding experiment, taking especial pains to get rid of all the
chlorophyll by changing the alcohol as many times as may be neces-
sary. What does this experiment show in regard to the consump-
tion of starch in the leaf? What has caused its disappearance?

182. Rate at which Starch is manufactured. — The
amount of starch made in a day by any given area of

1 The leaves, collected as above described, may, after boiling, be kept in
alcohol for winter use. They also make excellent material for the micro-
scopical study of starch in the leaf.

FIG. 123.— Leaf of Tropaeo-
lum partly covered with
Disks of Cork and ex-
posed to Sunlight.

MINUTE STRUCTURE OF LEAVES 171

foliage must depend on the kind of leaves, the tempera-
ture of the air, the intensity of the sunlight, and some
other circumstances. Sunflower leaves and pumpkin or
squash leaves have been found to manufacture starch at
about the same rate. In a summer day fifteen hours long
they can make nearly three-quarters of an ounce of starch
for each square yard of leaf-surface. A full-grown squash
leaf has an area of about one and one-eighth square feet,
and a plant may bear as many as 100 leaves. What would
be the daily starch-making capacity of such a plant ? l

183. Assimilation. — From the starch in the leaf, grape-
sugar or malt-sugar is readily formed, and some of this in
turn is apparently combined on the spot with nitrogen,
sulphur, and phosphorus. These elements are derived
from nitrates, sulphates, and phosphates, taken up in a
dissolved condition by the roots of the plant and trans-
ported to the leaves. The details of the process are not
understood, but the result of the combination of the
sugars or similar substances with suitable (very minute)
proportions of nitrogen, sulphur, and phosphorus is to
form complex nitrogen compounds. These are not pre-
cisely of the same composition as the living protoplasm
of plant-cells or as the reserve proteids stored in seeds
(Sects. 14, 17), stems (Sect. 127), and other parts of
plants, but are readily changed into protoplasm or proteid
foods as necessity may demand.

Assimilation is by no means confined to leaves ; indeed,
most of it, as above suggested, must take place in other
parts of the plant. For instance, the manufacture of the
immense amounts of cellulose, of cork, and of the com-

1 See Pfeffer's Physiology of Plants, translated by Ewart, Vol. I, p. 324.

172 FOUNDATIONS OF BOTANY

pound (ligniri) characteristic of wood-fiber, that go to make
up the main bulk of a large tree must be carried on in the
roots, trunk, and branches of the tree.

184. Digestive Metabolism. — Plant-food in order to be
carried to the parts where it is needed must be dissolved,
and this dissolving often involves a chemical change and
is somewhat similar to digestion as it occurs in animals.
The newly made starch in the leaf must be changed to a
sugar or other substance soluble in water before it can be
carried to the parts of the plant where it is to be stored
or to rapidly growing parts where it is to be used for
building material. On the other hand, starch, oil, and
such insoluble proteids as are deposited in the outer por-
tion of the kernel of wheat and other grains are extremely
well adapted to serve as stored food, but on account of
their insoluble nature are quite unfit to circulate through
the tissues of the plant. The various kinds of sugar are
not well adapted for storage, since they ferment easily in
the presence of warmth and moisture if yeast-cells or
suitable kinds of bacteria are present.

Two important differences between starch-making in
the green parts of plants and the non-constructive or the
destructive type of metabolism should be carefully noticed.
These latter kinds of metabolism go on in the dark as
well as in the light and do not add to the total weight
of the plant.

185. Excretion of Water and Respiration. — Enough has
been said in Sect. 174 concerning the former of these pro-
cesses. Respiration, or breathing in oxygen and giving
off carbonic acid gas, is an operation which goes on con-
stantly in plants, as it does in animals, and is necessary to

MINUTE STRUCTURE OF LEAVES

173

their life. For, like animals, plants get the energy with
which they do the work of assimilation, growth, reproduc-
tion, and performing their movements from the oxidation
of such combustible substances as oil, starch, and sugar.1

The amount of oxy-
gen absorbed and of car-
bonic acid given off is,
however, so trifling com-
pared with the amount
of each gas passing in
the opposite direction,
while starch-making is
going on in sunlight,
that under such circum-
stances it is difficult to
observe the occurrence
of respiration. In ordi-
nary leafy plants the FIG* 124. — Cross-Section of Stem of Marestail
leaves (through their (^™™) with Air-Passages, a.

stomata) are the principal organs for absorption of air, but
much air passes into the plant through the lenticels of
the bark.

In partly submerged aquatics especial provisions are
found for carrying the air absorbed by the leaves down to
the submerged parts. This is accomplished in pond lilies
by ventilating tubes which traverse the leaf-stalks length-
wise. In many cases such channels run up and down the
stem (Fig. 124).

1 The necessity of an air supply about the roots of the plant may be shown
by filling the pot or jar in which the hydrangea was grown for the transpi-
ration experiment perfectly full of water and noting the subsequent appear-
ance of the plant at periods twelve to twenty-four hours apart.

1T4

FOUNDATIONS OF BOTANY

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MINUTE STRUCTURE OF LEAVES 175

187. The Fall of the Leaf. — In the tropics trees retain
most of their leaves the year round ; a leaf occasionally
falls, but no considerable portion of them drops at any
one season.1 The same statement holds true in regard to
our cone-bearing evergreen trees, such as pines, spruces,
and the like. But the impossibility of absorbing soil-water
when the ground is at or near the freezing temperature
(Exp. XVII) would cause the death, by drying up, of
trees with broad leaf-surfaces in a northern winter. And
in countries where there is much snowfall, most broad-
leafed trees could not escape injury to their branches from
overloading with snow, except by encountering winter
storms in as close-reefed a condition as possible. For
such reasons our common shrubs and forest trees (except
the cone-bearing, narrow-leafed ones already mentioned)
are mostly deciduous, that is they shed their leaves at the
approach of winter.

The fall of the leaf is preceded by important changes
in the contents of its cells.

EXPERIMENT XXXVII

Does the Leaf vary in its Starch Contents at Different Seasons ?

Collect in early summer some leaves of several kinds of trees and
shrubs and preserve them in alcohol. Collect others as they are
beginning to drop from the trees in autumn and preserve them in
the same way. Test some of each lot for starch as described in
Sect. 181.

What does the result indicate?

Much of the sugary and protoplasmic contents of the
leaf disappears before it falls. These valuable materials

1 Except where there is a severe dry season.

176 FOUNDATIONS OF BOTANY

have been absorbed by the branches and roots, to be used
again the following spring.

The separation of the leaf from the twig is accomplished
by the formation of a layer of cork cells across the base of
the petiole in such a way that the latter finally breaks off
across the surface of the layer. A waterproof scar is thus
already formed before the removal of the leaf, and there is
no waste of sap dripping from the wound where the leaf-
stalk has been removed, and no chance for moulds to
attack the bark or wood and cause it to decay. In com-
pound leaves each leaflet may become separated from the
petiole, as is notably the case with the horse-chestnut leaf
(Fig. 102). In woody monocotyledons, such as palms, the
leaf-stalks do not commonly break squarely off at the base,
but wither and leave projecting stumps on the stem
(Plate VI).

The brilliant coloration, yellow, scarlet, deep red, and
purple, of autumn leaves is popularly but wrongly sup-
posed to be due to the action of frost. It depends merely
on the changes in the chlorophyll grains and the liquid
cell-contents that accompany the withdrawal of the proteid
material from' the tissues of the leaf. The chlorophyll
turns into a yellow insoluble substance after the valuable
materials which accompany it have been taken away, and
the cell sap at the same time may turn red. Frost per-
haps hastens the break-up of the chlorophyll, but individual
trees often show bright colors long before the first frost,
and in very warm autumns most of the changes in the foli-
age may come about before there has been any frost.

188. Tabular Review of Experiments.
[Continue the table from Sect. 128.]

PLATE VI. — Fan Palms

MINUTE STRUCTURE OF LEAVES 177

189. Review Summary of Minute Structure of Leaves.1

General structure, distribution of
parenchyma, andprosenchyma

Layers of tissue seen on a cross-
section

Structure of epidermis . . .

Structure of stomata . . . .

Distribution of stomata . . .

Structure and distribution of
chlorophyll bodies . . . ,

190. Review Summary of Functions of Leaves.

nbro-vascular bundles
epidermis ....
stomata ....

Principal uses of J air spaces . . . .

palisade-cells . . ...
spongy parenchyma
waxy coating . . .
hairs

Substances received by the leaf . { from the air • • •

[ from the soil .

Substances manufactured by the leaf . .

Substances given off by the leaf . i: ," . { ?nto the air • • •

[ into the stem

Mineral substances accumulated in the leaf
Statistics in regard to transpiration . .
Statistics in regard to starch-making . .

1 Illustrate with sketches and diagrams.

CHAPTER XII
PROTOPLASM AND ITS PROPERTIES

191. The Cell in its Simplest Form. — Sufficient has
been said in the preceding chapters, and enough tissues
have been microscopically studied, to make it pretty clear
what vegetable cells, as they occur in flowering plants,
are like. In Chapter XI, leaf-cells have been taken for
granted and their work described in some detail. Before
going further, it is worth while, to consider the structure
of an individual cell, and to see of what kinds of activity
it is capable.

In studying the minute anatomy of bark, wood, pith,
and other tissues the attention is often directed to the
cell-wall without much regard to the nature of the cell-
contents. Yet the cell-wall is not the cell, any more than
the lobster shell or the crayfish shell is the lobster or the
crayfish. The contained protoplasm with its nucleus is the
cell.1 The cell reduced to its lowest terms need not have
a cell-wall, but may consist simply of a mass of proto-
plasm, usually containing a portion of denser consistency
than the main bulk, known as the nucleus.

Such cells, without a cell-wall, are not common in the vege-
table world, but are frequently encountered among animals.

192. The Slime Moulds.2 — One of the best examples of
masses of naked protoplasm leading an individual existence

1 See Kerner and Oliver's Natural History of Plants, Vol. I, pp. 21-51.

2 Strasburger, Noll, Schenk, and Schimper's Text-Book of Botany, pp. 50-52
and 302-305.

178

PROTOPLASM AND ITS PROPERTIES 179

is found in the slime moulds, which live upon rotten tan
bark, decaying wood, and so on. These curious organ-
isms have so many of the characteristics both of animals
and of plants that they have been described in zoologies
under the former title and in botanies under the latter
one. Perhaps it would not really be so absurd a state-
ment as it might seem, to say that every slime mould leads
the life of an animal during one period of its existence and
of a plant at another period. At any rate, whatever their
true nature, these little masses of unenclosed protoplasm
illustrate admirably some of the most important properties
of protoplasm. Slime moulds spring from minute bodies
called spores (Fig. 125, a) which differ from the seeds of
seed-plants not only in their microscopic size but still
more in their lack of an embryo. The spores of slime
moulds are capable, when kept dry, of preserving for
many years their power of germination, but in the pres-
ence of moisture and warmth they will germinate as soon
as they are scattered. During the process of germination
the spore swells, as shown at 5, and then bursts, discharging
its protoplasmic contents, as seen at c and d. This in a
few minutes lengthens out and produces at one end a hair-
like cilium, as shown at e,f, g. These ciliated bodies are
called swarmspores, from their power of swimming freely
about by the vibrating motion of the cilia. Every swarm-
spore has at its ciliated end a nucleus, and at the other end
a bubble-like object which gradually expands, quickly dis-
appears, and then again expands. This contractile vacuole
is commonly met with in animalcules, and increases the
likeness between the slime moulds and many microscopic
animals. The next change of the swarmspores is into an

180

FOUNDATIONS OF BOTANY

Amoeba form (so called from one of the most interesting and
simplest of animals, the Amoeba, found on the surface of

FlG. 125. — A Slime Mould, (a-m, inclusive, x 540 times, n x 90 times.)

mud and the leaves of water plants). In this condition,
as shown at h, i, k, the spores creep about over the sur-
face of the decaying vegetable material on which the

PROTOPLASM AND ITS PROPERTIES 181

slime moulds live. Their movement is caused by a thrust-
ing out of the semi-liquid protoplasm on one side of the
mass, and a withdrawal of its substance from the other
side. At length many amoeba-shaped bodies unite, as at Z,
to form a larger mass, w, which finally increases to the
protoplasmic network shown at n. This eventually col-
lects into a roundish or egg-shaped firm body, inside of
which a new crop of spores is produced. It is not easy to
trace the manner in which the nourishment of these simple
plants is taken. Probably they absorb it from the decay-
ing matter upon which they live during their amoeba-like
period, and after they have formed the larger masses,, n.
193. Characteristics of Living Protoplasm.1 — The behav-
ior of the slime moulds during their growth and transfor-
mations, as just outlined, affords a fair idea- of several of
the remarkable powers which belong to living protoplasm,
which have been summed up as follows :

(1) The power to take up new material into its own
substance (selective absorption). This is not merely a proc-
ess of soaking up liquids, such as occurs when dry earth
or a sponge is moistened. The protoplasmic lining of a
root-hair, for example, selects from the soil-water some
substances and rejects others (Sect. 65).

(2) The ability to change certain substances into others
of different chemical composition (metabolism, Sect. 176).
Carbon dioxide and water, losing some oxygen in the
process, are combined into starch; starch is changed into
various kinds of sugar and these back into starch again ;
starch becomes converted into vegetable acids, into cellu-
lose, or into oil ; or the elements of starch are combined

1 See Huxley's Essays, Vol. I, essay on " The Physical Basis of Life."

182 FOUNDATIONS OF BOTANY

with nitrogen to make various proteid compounds, either
for immediate use or for reserve food. Many other com-
plicated transformations occur.

(3) The power to cast off waste or used-up material
(excretion). Getting rid of surplus water (Sect. 174) and
of oxygen (Sect. 178) constitutes a very large part of the
excretory work of plants.

(4) The capacity for growth and the production of off-
spring (reproduction). These are especially characteristic
of living protoplasm. It is true that non-living objects
may grow in a certain sense, as an icicle or a crystal of
salt or of alum in a solution of its own material does.
But growth by the process of taking suitable particles
into the interior of the growing substance and arranging
them into an orderly structure (Fig. 126) is possible only
in the case of live protoplasm.

(5) The possession of the power of originating move-
ments not wholly and directly caused by any external
impulse (automatic movements). Such, for instance, are
the lashing movements of the cilia of the swarmspores
of slime moulds, or the slow pendulum movements of
Oscillatoria (Sect. 269), or the slow vibrating movements
of the stipules of the " telegraph plant " (Desmodium),
not uncommon in greenhouses.

(6) The power of shrinking or closing up (contractility).
This is illustrated by the action of the contractile vacuole
of the slime moulds and of many animalcules and by all
the muscular movements of animals.

(7) Sensitiveness when touched or otherwise disturbed,
for instance, by a change of light or of temperature
(irritability).

PROTOPLASM AND ITS PROPERTIES

183

194. Nature and Occurrence of Irritability in Plants.1 —
Mention has already been made of the fact that certain
parts of plants respond to suitable stimuli that is exciting

FIG. 126. —Protoplasm in Ovule and Fruit of Snowberry (Symphoricarpus

racemosus).
A, cells from ovule, x 340 ; JB, cells from an ovule further developed, x 340 ; C, D,

cells from pulp of fruit, x no ; n, nucleus ; p, protoplasm ; s, cell-sap.
In the young and rapidly growing cells, A and B, the cell-sap is not present, or

present only in small quantities, while in the older cells, C and D, it occupies

a large portion of the interior of the cell.

causes. Geotropic movements (Sect. 70) are due to the
stimulating effect of gravitation on roots or shoots.

1 See Strasburger, Noll, Schenk, and Schimper's Text-Book of Botany,
pp. 160-162 and 269-274.

184

FOUNDATIONS OF BOTANY

These movements are due to unequal growth induced in
the younger portions of the plant by the action of gravi-
£^ tation upon it. Other movements (of

yl ordinary foliage leaves, of the floral leaves

of many flowers, and of other parts of a
few flowers) are produced by changes in
the distention or turgescence of some of the
cells in the organs which move and have
nothing to do with growth. The closing
of the leaves of insect-catching plants is
briefly described in Sect. 410, and the
" sleep " of leaves, due to movements of
the pulvini, was described in Sect. 152.
A few facts in regard to the opening and
closing of flowers will be found in
Sect. 440.

The stimuli which cause movements of
leaves or of the irritable parts of flowers
are of several kinds. Light is the main
cause which induces leaves to open from
their night position to that usual in the
daytime. In the case of flowers, it is
sometimes light and sometimes warmth
FIG. 127. — stinging which causes them to open. Leaves which

Hair of Nettle, with . , , ^ ,

Nucleus. (Much catch insects may be made to close by
magnified.) The ar- touching them, but the sensitive-plants,

rows show the direc-
tion of the currents of which there are several kinds found in

the United States, and a much more sensi-
tive one in tropical America, all fold their leaflets, on
being touched, into the same position which they assume
at night.

PROTOPLASM AND ITS PROPERTIES 185

195. Circulation of Protoplasm. — When confined by a
cell-wall, protoplasm often manifests a beautiful and con-
stant rotating movement, traveling incessantly up one
side of the cell and down the other.1 A more complicated
motion is the circulation of protoplasm, shown in cells of
the jointed blue hairs in the flower of the common spider-
wort and in the stinging hairs of the nettle (Fig. 127).
The thin cell- wall of each hair is lined with a protoplasmic
layer in which are seen many irregular, thread-like cur-
rents, marked by the movements of the granules, of which
the protoplasmic layer is full.

1 See Huxley and Martin's Elementary Biology, under Chara.

CHAPTER XIII

INFLORESCENCE, OR ARRANGEMENT OF FLOWERS
ON THE STEM

196. Regular Positions for Flower-Buds. — Flower-buds,
like leaf-buds, occur regularly either in the axils of leaves
or at the end of the stem or branch and are therefore
either axillary or terminal.

197. Axillary and Solitary Flowers; Indeterminate
Inflorescence. — The simplest possible arrangement for

flowers which arise from the axils of
leaves is to have a single flower spring
from each leaf -axil. Fig. 128 shows
how this plan appears in a plant with
opposite leaves. As long as the stem
continues to grow, the production of new
leaves may be followed by that of new

FIG. 128. — Axillary and
Solitary Flowers of
Pimpernel.

FIG. 129. — Raceme of
Common Red Currant.
p, peduncle ; p', pedicel ; br, bract.

flowers. Since there is no definite limit to the number
of flowers which may appear in this way, the mode of
flowering just described (with many others of the same
general character) is known as indeterminate inflorescence.

186

ARRANGEMENT OF FLOWERS ON THE STEM 187

FIG. 130. — Simple Umbel of Cherry.

198. The Racemes and Related Forms. — If the leaves
along the stem were to become very much dwarfed and the

flowers brought closer together,
as they frequently are, a kind
of flower-cluster like that of the
currant (Fig. 129) or the lily-
of-t he-valley would result. Such
an inflorescence is called a ra-
ceme; the main flower-stalk is
known as the peduncle ; the little
individual flower-stalks are pedi-
cels, and the small, more or
less scale -like leaves of the
peduncle are bracts.1
Frequently the lower pedicels of a cluster on the
general plan of the raceme are longer than the upper
ones and make a some-
what flat-topped cluster,
like that of the hawthorn,
the sheep laurel, or the
trumpet creeper. This
is called a corymb.

In many cases, for ex-
ample the parsnip, the
Sweet Cicely, the gin-
seng, and the cherry, a
group of pedicels of
nearly equal length

FIG. 131. — Catkins of Willow.
A, staminate flowers ; JS, pistillate flowers.

1 It is hardly necessary to say that the teacher will find it better in every
way, if material is abundant, to begin the study of flower-clusters with the
examination of typical specimens by the class.

188

FOUNDATIONS OF BOTANY

spring from about the same point. This produces a
flower-cluster called the umbel (Fig. 130).

199. Sessile Flowers and Flower-Clusters. — Often the
pedicels are wanting, or the flowers are sessile, and then
a modification of the raceme is produced which is called
a spike, like that of the plantain (Fig. 132). The
willow, alder, birch, poplar, and many other common
trees bear a short, flexible, rather scaly spike (Fig.
131), which is called a catkin.

The peduncle of a spike is -often so much short-
ened as to bring the flowers into a somewhat globu-
lar mass. This is called a head (Fig. 132). Around
the base of the head usually
occurs a circle of bracts known
as the involucre. The same
name is given to a set of bracts
which often surround the bases
of the pedicels in an umbel.

200. The Composite Head. —
The plants of one large group,
of which the dandelion, the
daisy, the thistle, and the sun-
flower are well-known members, bear their flowers in
close involucrate heads on a common receptacle. The
whole cluster looks so much like a single flower that it is
usually taken for one by non-botanical people. In many
of the largest and most showy heads, like that of the
sunflower and the daisy, there are two kinds of flowers,
the ray-flowers, around the margin, and the tubular disk-
flowers of the interior of the head (Fig. 133). The early
botanists supposed the whole flower-cluster to be a single

FIG. 132. — Spike of Plantain and
Head of Red Clover.

ARRANGEMENT OF FLOWERS ON THE STEM 189

FIG. 133.— Head of Yarrow.

A, top view. (Magnified.) B, lengthwise section. (Magnified.) re, receptacle ; i,
involucre ; r, ray-flowers ; d, disk-flowers ; c, corolla ; s, stigma ; ch, chaff,
or bracts of receptacle.

FIG. 134.
Panicle of Oat.

FIG. 135. — Compound Umbel
of Carrot.

190

FOUNDATIONS OF BOTANY

compound flower. This belief gave rise to the name of
one family of plants, Compositoe, that is, plants with com-
pound flowers. In such heads as those of the thistle, the
cud weed, and the everlasting there are no ray-flowers,
and in others, like those of the dandelion and the chicory,
all the flowers are ray-flowers.

201. Compound Flower-Clusters. — If the pedicels of a
raceme branch, they may produce a compound raceme, or

A B C &£

FIG. 136. — Diagrams of Inflorescence.
A, panicle ; B, raceme ; C, spike ; D, umbel ; E, head.

panicle, like that of the oat (Fig. 134).1 Other forms of
compound racemes have received other names.

An umbel may become compound by the branching of
its flower-stalks (Fig. 135), each of which then bears a
little umbel, an umbellet.

202. Inflorescence Diagrams. — The plan of inflorescence
may readily be indicated by diagrams like those of Fig. 136.

The student should construct such diagrams for some rather corn-
plicated flower-clusters, like those of the grape, horse-chestnut or
buckeye, hardback, vervain, or many grasses.

1 Panicles may also be formed by compound cymes (see Sect. 204).

ARRANGEMENT OF FLOWERS ON THE STEM 191

203. Terminal Flowers ; Determinate Inflorescence. -
The terminal bud of a stem may be a flower-bud. In this
case the direct growth of the stem is stopped or deter-
mined by the appearance of the flower ; hence such plants
are said to have a determinate inflorescence. The simplest
possible case of this kind is that

in which the stem bears but one
flower at its summit.

204. The Cyme. — Very often
flowers appear from lateral (axil-
lary) buds, below the terminal
flower, and thus give rise to a
flower-cluster called a cyme.
This may have only three flowers,
and in that case would look very
much like a three-flowered
umbel. But in the raceme,
corymb, and umbel the order of
flowering is from below upward,
or from the outside of the clus-
ter inward, because the lowest or the outermost flowers
are the oldest, while in determinate forms of inflorescence
the central flower is the oldest, and therefore the order of
blossoming is from the center outwards. Cymes are very
commonly compound, like those of the elder and of many
plants of the pink family, such as the Sweet William and
the mouse-ear chickweed (Fig. 137). They may also, as
already mentioned, be panicled, thus making a cluster
much like Fig. 136, A.

FIG. 137. — Compound Cyme of

Mouse-Ear Chickweed.
t, the terminal (oldest) flower.

CHAPTER XIV
THE STUDY OF TYPICAL FLOWERS

(Only one of the three flowers described to be studied by aid of these
directions.)

205, The Flower of the Trillium. — Cut off the flower-stalk rather
close to the flower; stand the latter, face down, on the table, and
draw the parts then shown. Label the green leaf-like parts sepals,
and the white parts, which alternate with these, petals. Turn the
flower face up, and make another sketch, labeling the parts as before,
together with the yellow enlarged extremities or anthers of the stalked
organs called stamens.

Note and describe the way in which the petals alternate with the
sepals. Observe the arrangement of the edges of the petals toward
the base, — how many with both edges outside the others, how many
with both edges inside, how many with one edge in and one out.

Note thja veining of both sepals and petals, more distinct in
which set?1

Pull off a sepal and make a sketch of it, natural size ; then remove
a petal, flatten it out, and sketch it, natural size.

Observe that the flower-stalk is enlarged slightly at the upper end
into a rounded portion, the receptacle, on which aft the parts of the
flower rest.

Note how the six stamens arise from the receptacle and their
relations to the origins of the petals. Remove the remaining petals

1 In flowers with delicate white petals the distribution of the fibro-vascular
bundles in these can usually be readily shown by standing the freshly cut end
of the peduncle in red ink for a short time, until colored veins begin to appear
in the petals. The experiment succeeds readily with apple, cherry, or plum
blossoms ; with white gilliflower the coloration is very prompt. Lily-of-the-
valley is perhaps as interesting a flower as any on which to try the experi-
ment, since the well-defined stained stripes are separated by portions quite
free from stain, and the pistils are also colored.

192

THE STUDY OF TYPICAL FLOWERS 193

(cutting them off near the bottom with a knife), and sketch the sta-
mens, together with the other object, the pistil, which stands in the
center.

Cut off one stamen, and sketch it as seen through the magnifying
glass. Notice that it consists of a greenish stalk, the f lament, and
a broader portion, the anther (Fig. 149). The latter is easily seen
to contain a prolongation of the green filament, nearly surrounded
by a yellow substance. In the bud it will be found that the anther
consists of two long pouches or anther-cells, which are attached by
their whole length to the filament, and face inward (towards the
center of the flower). When the flower is fairly open, the anther-
cells have already split down their margins, and are discharging a
yellow, somewhat sticky powder, the pollen.

Examine one of the anthers with the microscope, using the two-
inch objective, and sketch it. • % '

Cut away all the stamens, and sketch the pistil. It consists of a
stout lower portion, the ovary, which is six-ridged or angled, and
which bears at its summit three slender stigmas.

In another flower, which has begun to wither (and in which the
ovary is larger than in a newly opened flower), cut the ovary across
about the middle, and try to make out with the magnifying glass
the number of chambers or cells which it contains. Examine the
cross-section with the two-inch objective ; sketch it, and note partic-
ularly the appearance and mode of attachment of the undeveloped
seeds or ovules with which it is filled. Make a vertical section of
another rather mature ovary, and examine this in the same way.

Using a fresh flower*, construct a diagram to show the relation of
the parts on an imaginary cross-section, as illustrated in Fig. 157. 1
Construct a diagram of a longitudinal section of the flower, on the
general plan of those in Fig. 155, but showing the contents of the
ovary.

Make a tabular list of the parts of the flower, beginning with the
sepals, giving the order of parts and number in each set.

1 It is important to notice that such a diagram is not a picture of the section
actually produced by cutting through the flower crosswise at anyone level,
but that it is rather a projection of the sections through the most typical part
of each of the floral organs.

194 FOUNDATIONS OF BOTANY

206. The Flower of the Tulip.1 — Make a diagram of a side view
of the well-opened flower, as it appears when standing in sunlight.
Observe that there is a set of outer flower-leaves and a set of inner
ones.2 Label the outer set sepals and the inner set petals. In most
flowers the parts of the outer set are greenish, and those of the inner
set of some other color. It is often convenient to use the name
perianth, meaning around the flower, for the two sets taken together.
Note the white waxy bloom on the outer surface of the outer seg-
ments of the perianth. What is the use of this ? Note the manner
in which the inner segments of the perianth arise from the top of the
peduncle and their relation to the points of attachment of the outer
segments. In a flower not too widely opened, note the relative posi-
tion of the inner segments of the perianth, how many wholly outside
the other two, how many wholly inside, how many with one edge in
and one edge out.

Remove one of the sepals by cutting it off close to its attachment
to the peduncle, and examine the veining by holding it up in a strong
light and looking through it. Make a sketch to show the general
outline and the shape of the tip.

Examine a petal in the same way, and sketch it.

Cut off the remaining portions of the perianth, leaving about a
quarter of an inch at the base of each segment. Sketch the upright,
triangular, pillar-like object' in the center, label it pistil, sketch the
organs which spring from around its base, and label these stamens.

Note the fact that each stamen arises from a point just above and
within the base of a segment of the perianth. Each stamen consists
of a somewhat conical or awl-shaped portion below, the filament, sur-
mounted by an ovate linear portion, the anther. Sketch one of the
stamens about twice natural size and label it x 2. Is the attach-
ment of the anther to the filament such as to admit of any nodding
or twisting movement of the former V In a young flower, note the
two tubular pouches or anther-cells of which the anther is composed,
and the slits by which these open. Observe the dark-colored pollen

1 Tulipa Gesneriana. As the flowers are rather expensive, and their parts
are large and firm, it is not absolutely necessary to give a flower to each pupil,
but some may be kept entire for sketching and others dissected by the class.
All the flowers must be single.

2 Best seen in a flower which is just opening.

THE STUDY OF TYPICAL FLOWERS 195

which escapes from the anther-cells and adheres to paper or to the
fingers. Examine a newly opened anther with the microscope, using
the two-inch objective, and sketch it.

Cut away all the stamens and note the two portions of the pistil,
a triangular prism, the ovary, and three roughened scroll-like objects
at the top, the three lobes of the stigma. Make a sketch of these
parts about twice natural size, and label them x 2. Touch a small
camel's-hair pencil to one of the anthers, and then transfer the pollen
thus removed to the stigma. This operation is merely an imitation
of the work done by insects which visit the flowers out of doors.
Does the pollen cling readily to the rough stigrnatic surface ? Examine
this adhering pollen with the two-inch objective, and sketch a few
grains of it, together with the bit of the stigma to which it clings.
Compare this drawing with Fig. 162. Make a cross-section of the
ovary about midway of its length, and sketch the section as seen
through the magnifying glass. Label the three chambers shown
cells of the ovary l or locules, and the white egg-shaped objects within
ovules.2

Make a longitudinal section of another ovary, taking pains to
secure a good view of the ovules, and sketch as seen through the
magnifying glass.

Making use of the information already gained and the cross-
section of the ovary as sketched, construct a diagram of a cross-
section of the entire flower on the same general plan as those shown
in Fig. 157.3

Split a flower lengthwise,4 and construct a longitudinal section of
the entire flower on the plan of those shown in Fig. 155, but showing
the contents of the ovary.

207. The Flower of the Buttercup. — Make a diagram of the
mature flower as seen* in a side view, looking a little down into it.
Label the pale greenish-yellow, hairy, outermost parts sepals, and

1 Notice that the word cell here means a comparatively large cavity, and is
not used in the same sense in which we speak of a wood-cell or a pith-cell.

2 The section will be more satisfactory if made from an older flower, grown
out of doors, from which the perianth has fallen. In this case label the con-
tained objects seeds.

3 Consult also the footnote on p. 193.

4 One will do for an entire division of the class.

196 FOUNDATIONS OF BOTANY

the larger bright yellow parts above and within these petals, and
the yellow-knobbed parts which occupy a good deal of the interior
of the flower stamens.

Note the difference in the position of the sepals of a newly
opened flower and that of the sepals of a flower which has opened as
widely as possible. Note the way in which the petals are arranged
in relation to the sepals. In an opening flower observe the arrange-
ment of the edges of the petals, how many entirely outside the
others, how many entirely inside, how many with one edge in and
the other out.

Cut off a sepal and a petal, each close to its attachment to the
flower ; place both, face down, on a sheet of paper, and sketch about
twice the natural size and label it x 2. Describe the difference in
appearance between the outer and the inner surface of the sepal and
of the petal. Note the little scale at the base of the petal, inside.

Strip off all the parts from a flower which has lost its petals,
until nothing is left but a slender conical object a little more than
an eighth of an inch in length. This is the receptacle or summit of
the peduncle.

In a fully opened flower, note the numerous yellow-tipped stamens,
each consisting of a short stalk, the filament, and an enlarged yellow
knob at the end, the anther. Note the division of the anther into
two portions, which appear from the outside as parallel ridges, but
which are really closed tubes, the anther-cells.

Observe in the interior of the flower the somewhat globular mass
(in a young flower almost covered by the stamens). This is a group
of pistils. Study one of these groups in a flower from which the
stamens have mostly fallen off, and make an enlarged sketch of the
head of pistils. Remove some of the pistils from a mature head,
and sketch a single one as seen with the magnifying glass. Label
the little knob or beak at the upper end of the pistil stigma, and the
main body of the pistil the ovary. Make a section of one of the
pistils, parallel to the flattened surfaces, like that shown in Fig, 150,
and note the partially matured seed within.

CHAPTER XV

PLAN AND STRUCTURE OF THE FLOWER AND ITS
ORGANS

208. Parts or Organs of the Flower. — Most showy
flowers consist, like those studied in the preceding chap-
ter, of four circles or sets of organs, the sepals, petals,
stamens, and pistils. The sepals, taken together, consti-
tute the calyx; the petals, taken together, constitute the
corolla (Fig. 138).1 Some-
times it is convenient to have
a word to comprise both calyx
and corolla ; for this the term
perianth is used. A flower
which contains all four of
these sets is said to be com-
plete. Since the work of the
flower is to produce seed, and
seed-forming is due to the
cooperation of stamens and
pistils, or, as they are, often
called from their relation to the reproductive organs of
spore-plants, micro sporophylls and macrosporophylls (see
Sect. 374), these are known as the essential organs
(Fig. 138). The simplest possible pistil is a dwarfed and

1 The flower of the waterleaf Hydrophyllum canadense, modified by the
omission of the hairs on the stamens, is here given because it shows so plainly
the relation of the parts.

197

FIG. 138. — The Parts of the Flower.

cat, calyx ; cor, corolla ; st,

stamens; p, pistil.

198

FOUNDATIONS OF BOTANY

greatly modified leaf (Sect. 222), adapted into a seed-
bearing organ. Such a pistil may be one-seeded, as in
Fig. 166, or several-seeded, as in the diagrammatic one
(Fig. 150) ; it is called a carpel. The calyx and corolla are
also known as the floral envelopes. Flowers which have
the essential organs are called perfect flowers. They may,
therefore, be perfect without being complete. Incomplete
flowers with only one row of parts in the
perianth are said to be apetalous (Fig. 139).
209. Regular and Symmetrical Flowers.
— A flower is regular if all the parts of
the same set or circle are alike in size and
shape, as in the stonecrop (Fig. 140). Such
flowers as that of the violet, the monkshood,
FIG. 139. — Apetai- and the sweet pea (Fig. 141) are irregular.

ous Flower of ^ . n

(European) wild Symmetrical flowers are those whose calyx,

corolla, circle of stamens, and set of

carpels consist each of the same number of parts, or in

which the number in every case is a multiple of the

smallest number found in any set. The stonecrop is

I II

FIG. 140. — Flower of Stonecrop.
I, entire flower (magnified) ; II, vertical section (magnified).

symmetrical, since it has five sepals, five petals, ten sta-
mens, and five carpels. Roses, mallows, and mignonette

STRUCTURE OF THE FLOWER AND ITS ORGANS 199

are familiar examples of flowers which are unsymmet-
rical because they have a large, indefinite number of
stamens ; the portulaca is unsymmetrical, since it has two
divisions of the calyx, five or six petals, and seven to
twenty stamens.

210. The Receptacle. — The parts of the flower are
borne on an expansion of the peduncle, called the recep-
tacle. Usually, as in the flower of the grape (Fig. 250),
this is only a slight enlargement of the peduncle, but in

FIG. 141. — Irregular Corolla of
Sweet Pea.

I A, side view ; B, front view ; s, stand-

A ard ; w w, wings ; k, keel.

the lotus and the magnolia the receptacle is of great size,
particularly after the petals have fallen and the seed has
ripened. The receptacle of the rose (Fig. 142) is hollow,
and the pistils arise from its interior surface.

211. Imperfect or Separated Flowers. - - The stamens
and pistils may be produced in separate flowers, which
are, of course, imperfect. This term does not imply that
such flowers do their work any less perfectly than others,
but only that they have not both kinds of essential organs.
In the very simple imperfect flowers of the willow (Fig.
143) each flower of the catkin (Fig. 131) consists merely

200 FOUNDATIONS OF BOTANY

of a pistil or a group of (usually two) stamens, springing
from the axil of a small bract.

Staminate and pistillate flowers may be borne on differ-
ent plants, as they are in the willow, or they may be
borne on the same plant, as in the hickory and the hazel,
among trees, or in the castor-oil plant, Indian corn, and
the begonias. When staminate and pistillate flowers are
borne on separate plants, such a plant is said to be
dioecious, that is, of two households ; when both kinds of
flower appear on the same individual, the plant is said
to be monoecious, that is, of one household.

212, Study of Imperfect Flowers. — Examine, draw, and describe
the imperfect flowers of some of the following dioecious plants and
one of the monoecious plants : l

f early meadow rue.

Dioecious plants ^ willow.

! poplar.

f walnut, oak, chestnut.

Monoecious plants < hickory, alder, beech.

I birch, hazel, begonia.

213. Union of Similar Parts of the Perianth. — The
sepals may appear to join or cohere to form a calyx which
is more or less entirely united into one piece, as in Figs.
139 and 148. In this case the calyx is said to be gamo-
sepalous, that is, of wedded sepals. In the same way the
corolla is frequently gamopetalous, as in Figs. 144-148.
Frequently the border or limb of the calyx or corolla is
more or less cut or lobed. In this case the projecting

1 For figures or descriptions of these or allied flowers consult Gray's
Manual of Botany, Emerson's Trees and Shrubs of Massachusetts, NewhalPs
Trees of the Northern United States, or Le Maout and Decaisne's Traite
General de Botanique.

STRUCTURE OF THE FLOWER AND ITS ORGANS 201

FIG. 142.

portions of the limb are known as divisions, teeth, or
lobes.1 Special names of great use in accurately describing
plants are given to a large number of forms of the gamo-
petalous corolla. Only a few of these
names are here given, in connection with
the figures.

When the parts of either circle of the
perianth are wholly unconnected with each
other, that is, polysepalous or polypetalous,
such parts are said to be distinct.

214. Parts of the Stamen and the Pistil.
— The stamen usually consists of a hollow
portion, the anther (Fig. 149, a), borne on a
ARose,Longitudi- stalk called the filament (Fig. 149, /), which
is often lacking. Inside the anther is a pow-
dery or pasty substance called pollen or microspores (Sect.
374). The pistil usually consists of a small chamber, the
ovary, which contains the ovules, macrospores (Sect. 374),
or rudimentary seeds, a slen-
der portion or stalk, called the
style, and at the top of this a
ridge, knob, or point called
the stigma. These parts are
all shown in Fig. 150. In
many pistils the stigma is
borne directly on the ovary.
215. Union of Stamens with
Each Other. — Stamens may

be wholly Unconnected With A, staminate flower ; B, pistillate flower.

1 It would not be safe to assume that the gamosepalous calyx or the gamo-
petalous corolla is really formed by the union of separate portions, but it is
very convenient to speak of it as if it were.

FIG. 143. — Flowers of Willow.
(Magnified.)

202

FOUNDATIONS OF BOTANY

each other or distinct, or they may cohere by their fila-
ments into a single group, when they are said to be
monadelphous, of one brotherhood (Fig.
151), into two groups (diadelphous) (Fig.
152), or into many groups. In some
flowers the stamens are held together in
a ring by their coherent anthers (Fig.
153).

216. Union of Pistils. — The pistils
may be entirely separate from each
other, distinct and simple, as they are

FIG. 144. -Bell-Shaped . _ t"

corolla of Beii-Fiower in the buttercup and the stonecrop, or
(Campanula). several may join to form one compound

pistil of more or less united carpels. In the latter case
the union generally affects the ovaries, but often leaves
the styles separate, or it may result
in joining ovaries and styles, but
leave the stigmas separate or at any
rate lobed, so as to show of how
many separate carpels the compound
pistil is made up. Even when there
is no external sign to show the
compound nature of
the pistil, it can usu-
ally be recognized
from the study of
a cross-section of the

FIG. 145. — Salver-Shaped
Corolla of Jasmine.
(Magnified.)

FIG. 146.

Wheel-Shaped Corolla
of Potato.

ovary.

217. Cells of the
Ovary ; Placentas. — Compound ovaries are very com-
monly several-celled, that is, they consist of a number of

STRUCTURE OF THE FLOWER AND ITS ORGANS 203

separate cells1 or chambers, more scientifically known
as locules. Fig. 154, B, shows a three-celled ovary
seen in cross-section. The ovules are not borne indis-
criminately by any part of the lining of the ovary. In
one-celled pistils they frequently grow in a line running
along one side of the ovary, as in the pea pod (Fig. 271).
The ovule-bearing line is called a placenta; in compound
pistils there are commonly as many placentas as there are

FIG. 147. — Tubu-
lar Corolla, from
Head of Bache-
lor's Button.

FIG. 148. — Labi-
ate or Ringent
Corolla of Dead
Nettle.

FIG. 149. — Parts of a

Stamen.

A, front ; B, back ; a, an-
ther ; c, connective;
/, filament.

FIG. 150. — Parts
of the Pistil.

ov, ovary.
sty, style.
stig, stigma.

separate pistils joined to make the compound one. Pla-
centas on the wall of the ovary, like those in Fig. 154, A,
are called parietal placentas ; those which occur as at B,
in the same figure, are said to be central, and those which,
like the form represented in 0 of the same figure, consist
of a column rising from the bottom of the ovary are
called free central placentas.

1 Notice that the word cell is here used in an entirely different sense ^rom
that in which it has been employed in the earlier chapters of this book. As
applied to the ovary, it means a chamber or compartment.

204

FOUNDATIONS OF BOTANY

218. Union of Separate Circles. — The members of one
of the circles of floral organs may join those of another
circle, thus becoming adnate, adherent, or consolidated.

In Fig. 139 the calyx tube is adnate to the
ovary. In this case the parts of the flower do
not all appear to spring from the receptacle.
Fig. 155 illustrates three common cases as
regards insertion of the parts of the flower.
In I they are all inserted on the receptacle,
and the corolla and stamens are said to be
hypogynous, that is, beneath the pistil. In II
the petals and the stamens appear as if they
had grown fast to the calyx for some distance,
so that they surround the pistil, and they are

therefore said to be perigynous, that is,

around the pistil. In III all the parts are

free or unconsolidated, except the petals

arid stamens ; the stamens may be described

as epipetalous, that is, growing on the petals.
Sometimes some or all
of the other parts stand
upon the ovary, and such

FIG. 152. -Diadeiphous parts are said to be epig-

Stamens of Sweet Pea. ynou^ that IS, On the

ovary, like the petals and stamens of the
white water-lily (Fig. 156).

219. Floral Diagrams. — Sections (real
or imaginary) through the flower length-
wise, like those of Fig. 155, help greatly

in giving an accurate idea of the relative «,™»ted anthers;/,

filaments, bearded

position of the floral organs. Still more on the sides.

<•

FIG. 153. — Stamens
of a Thistle, with
Anthers united
into a King.

STRUCTURE OF THE FLOWER AND ITS ORGANS 205

important in this way are cross-sections, which may be
recorded in diagrams like those of Fig. 157. l In con-
structing such diagrams it
will often be necessary to
suppose some of the parts
of the flower to be raised
or lowered from their true
position, so as to bring
them into such relations
that all could be cut by a
single section. This would, for instance, be necessary
in making a diagram for the cross-section of the flower

A~ ~B~ C

FIG. 154. — Principal Types of Placenta.
A, parietal placenta ; B, central placenta ;
C, free central placenta ; A and B, trans-
verse sections ; C, longitudinal section.

I II III

FIG. 155. — Insertion of the

Floral Organs.

I, Hypogynous, all the other parts on
the receptacle, beneath the pistil ;
II, Perigynous, petals and stamens
apparently growing out of the calyx,
around the pistil ; III, corolla
hypogynous, stamens epipetalous.

FIG. 156. — White Water-Lily. The
inner petals and the stamens grow-
ing from the ovary.

of the white water-lily, of which a partial view of one
side is shown in Fig. 156.2

1 For floral diagrams see Le Maout and Decaisne's Traite General de
Botanique, or Eichler's Bliithendiagramme.

2 It is best to begin practice on floral diagrams with flowers so firm and
large that actual sections of them may be cut with ease and the relations of
the parts in the section readily made out. The tulip is admirably adapted
for this purpose.

206

FOUNDATIONS OF BOTANY

Construct diagrams of the longitudinal section and the
transverse section of several large flowers, following the
method indicated in Figs. 155 and 157, but making
• the longitudinal section show

the interior of the ovary.1 It
is found convenient to distin-

I II III

FIG. 157. — Diagram of Cross-Sections of Flowers.

I, columbine ; II, heath family ; III, iris family. In each diagram the dot along-
side the main portion indicates a cross-section of the stem of the plant. In
II every other stamen is more lightly shaded, because some plants of the
heath family have five and some ten stamens.

guish the sepals from the petals by representing the
former with midribs. The diagrammatic symbol for a
stamen stands for a cross-section of the anther, and that
for the pistil is a section of the ovary. If any part is
lacking in the flower (as in the case of flowers which
have some antherless filaments) the missing or abortive
organ may be indicated by a dot. In the diagram of the
Iris Family (Fig. 157, III) the three dots inside the flower
indicate the position of a second circle of stamens, found
in most flowers of monocotyledons but not found in this
family.

1 Among the many excellent early flowers for this purpose may be men-
tioned trillium, bloodroot, dogtooth violet, marsh marigold, buttercup, tulip
tree, horse-chestnut, Jeffersonia, May-apple, cherry, apple, crocus, tulip,
daffodil, primrose, wild ginger, cranesbill, locust, bluebell.

" STRUCTURE OF THE FLOWER AND ITS ORGANS 207
220. Review Summary of Chapter XV.1

Kinds of flowers as regards number of circles or I 2.
•jets of organs present j 3.

U
Kinc's as regards numerical plan

Kinds as regards similarity of parts of the same f 1.
circle I 2.

Parts of a stamen

Parts of a pistil

Stamens as regards union with each other

Pistils as regards union with each other .

Degree of union of separate circles . .

1 Illustrate by sketches.

CHAPTER XVI

TRUE NATURE OF FLORAL ORGANS; DETAILS OF
THEIR STRUCTURE; FERTILIZATION

221, The Flower a Shortened and greatly Modified
Branch. — In Chapter VIII, the leaf-bud was explained
as being an undeveloped branch, which in its growth
would develop into a real branch (or a prolongation of
the main stem). Now, since flower-buds appear regularly

FIG. 158. — Transition from Bracts to Sepals in a Cactus Flower.

either in the axils of leaves or as terminal buds, there is
reason to regard them as of similar nature to leaf-buds.
This would imply that the receptacle corresponds to the
axis of the bud shown in Fig. 86, and that the parts of
the flower correspond to leaves. There is plenty of evi-
dence that this is really true. Sepals frequently look
very much like leaves, and in many cacti the bracts

208

TRUE NATURE OF FLORAL ORGANS

209

about the flower are so sepal-like that it is impossible to
tell where the bracts end and the sepals begin (Fig. 158).
The same thing is true of sepals and petals in such flowers
as the white water-lily. In this flower there is a remark-
able series of intermediate steps, ranging all the way from
petals, tipped with a bit of anther, through stamens with
a broad petal-like filament, to regular stamens, as is shown
in Fig. 159, E, F, 6r, H. The same thing is shown in

FIG. 159. — Transitions from Petals to Stamens in White Water-Lily.
E, F, G, H, various steps between petal and stamen.

many double roses. In completely double flowers all the
essential organs are transformed by cultivation into petals.
In the flowers of the cultivated double cherry the pistils
occasionally take the form of small leaves, and some roses
turn wholly into green leaves.

Summing up, then, we know that flowers are altered
and shortened branches : (1) because flower-buds have as
regards position, the same kind of origin as leaf-buds ;
(2) because all the intermediate steps are found between
bracts, on the one hand, and stamens, on the other ; (3)

210 FOUNDATIONS OF BOTANY

because the essential organs are found to be replaced by
petals or even by green leaves.

The fact that leaves should be so greatly modified as
they are in flowers and given work to do wholly different
from that of the other kinds of leaves so far studied need
not strike one as exceptional. In many of the most highly
developed plants below the seed-plants, organs correspond-
ing to flowers are found, and these consist of modified
leaves, set apart for the work of reproducing (Sect. 367).

222. Mode of Formation of Stamens and Pistils from
Leaves. — It is hardly possible to state, until after Chap-
ter XXIII has been studied, how stamens stand related
to leaves.1

The simple pistil or carpel is supposed to be made on
the plan of a leaf folded along the midrib until its margins
touch, like the cherry leaf in Fig. 87. But the student
must not understand by this statement that the little
pistil leaf grows at first like an ordinary leaf and finally
becomes folded in. The united leaf-margins near the tip
would form the stigma, and the placenta would correspond
to the same margins, rolled slightly inwards, extending
along the inside of the inflated leaf-pouch. Place several
such folded leaves upright about a common center, and
their cross-section would be much like that of B in Fig.
154. Evidence that carpels are really formed in this way
may be gained from the study of such fruits as that of
the monkshood (Fig. 168), in which the ripe carpels may
be seen to unfold into a shape much more leaf -like than
that which they had while the pistil was maturing. What

1 "The anther answers exactly to the spore-cases of the ferns and their
allies, while the filament is a small specialized leaf to support it." For a
fuller statement, see Potter and Warming's Systematic Botany, pp. 236, 237.

TRUE NATURE OF FLORAL ORGANS

211

really occurs is this: the flower-bud, as soon as it has
developed far enough to show the first rudiments of the
essential organs, contains them in the form of minute
knobs. These are developed from the tissues of the plant
in the same manner as are the knobs in a leaf-bud, which
afterwards become leaves (Fig. 87, II) ; but as growth
and development progress
in the flower-bud, its con-
tents soon show themselves
to be stamens and pistils (if
the flower is a perfect one).

223. The Anther and its
Contents. — Some of the
shapes of the anthers may
be learned from Figs. 149
and 160.1 The shape of the FlG- 16°— Modes of *****&* Pollen-
anther and the way in which
it opens depend largely upon
the way in which the pollen
is to.be discharged and how it is carried from flower to
flower. The commonest method is to have the anther-
cells split lengthwise, as in Fig. 160, I. A few anthers
open by trap-doors like valves, as in II, and a larger
number by little holes at the top, as in III.

The pollen in many plants with inconspicuous flowers,
as the evergreen cone-bearing trees, the grasses, rushes,
and sedges, is a fine, dry powder. In plants with showy
flowers it is often somewhat sticky or pasty. The forms
of pollen grains are extremely various. Fig. 161 will
serve to furnish examples of some of the shapes which

(amaryllis);

berry); III, by a pore at the top of each

anther-lobe (nightshade).

1 See Kerner and Oliver's Natural History of Plants, Vol. II, pp. 86-95,

212 FOUNDATIONS OF BOTANY

the grains assume ; c in the latter figure is perhaps as
common a form as any. Each pollen grain consists mainly
of a single cell, and is covered by a moderately thick outer
wall and a thin inner one. Its contents are thickish
protoplasm, full of little opaque particles and usually
containing grains of starch and little drops of oil. The
knobs on the outer coat, as shown in Fig. 161 5, mark

a b c d e

FIG. 161. — Pollen Grains. (Very greatly magnified.)
a, pumpkin ; b, enchanter's nightshade ; c, Albuca ; d, pink ; e, hibiscus.

the spots at which the inner coat of the grain is finally
to burst through the outer one, pushing its way out in
the form of a slender, thin-walled tube.1

224, The Formation of Pollen Tubes. — This can be
studied in pollen grains which have lodged on the stigma
and there been subjected to the action of its moist surface.
It is, however, easier to cause the artificial production of
the tubes.

EXPERIMENT XXXVIII

Production of Pollen Tubes. — Place a few drops of suitably diluted
syrup with some fresh pollen in a concave cell ground in a micro-
scope slide ; cover with thin glass circle ; place under a bell-glass,
with a wet cloth or sponge, to prevent evaporation of the syrup, and
set aside in a warm place, or merely put some pollen in syrup in a

i See Kerner and Oliver's Natural History of Plants, Vol. II, pp. 95-104.

FERTILIZATION

213

watch crystal under the bell-glass. Examine from time to time to
note the appearance of the pollen tubes. Try several kinds of
pollen if possible, using syrups of various strengths. The follow-
ing kinds of pollen form tubes readily in syrups of the strengths
indicated.

Tulip . .. . -. . . . 1 to 3 per cent.

Narcissus . . « .. . : ' 3 to 5 "

Cytisus canariensis (called Genista by florists) 15 "

Chinese primrose 10 "

Sweet pea1 ...... 10 to 15 "

Tropa3olum1 . ^ . .. . 15 "

225. Microscopical Structure of the Stigma and Style. -
Under a moderate power of the microscope the stigma is
seen to consist of cells set irregularly over the surface,
and secreting a moist liquid to
which the pollen grains adhere (Fig.
162). Beneath these superficial cells
and running down through the style
(if there is one) to the ovary is
spongy parenchyma. In some pistils
the pollen tube proceeds through
the cell walls, which it softens by
means of a substance which it exudes
for that purpose. In other cases
(Fig. 163) there is a canal or passage,
along which the pollen tube travels
on its way to the ovule.

FIG. 162. — Stigma of Thorn-
Apple (Datura) with Pollen.
(Magnified.)

1 The sweet-pea pollen and that of Tropaeolum are easier to manage than
any other kinds of which the author has personal knowledge. If a concaved
slide is nqt available, the cover-glass may be propped up on bits of the thin-
nest broken cover-glasses. From presence of air or some other reason, the
formation of pollen tubes often proceeds most rapidly just inside the margin
of the cover-glass.

214

FOUNDATIONS OF BOTANY

226. Fertilization. — By fertilization in seed-plants the
botanist means the union of a generative cell from a pol-
p len grain with that of an egg-cell
at the apex of the embryo sac
(Fig. 165). This process gives
rise to a cell which contains
material derived from the pollen
and from the egg-cell. In a
great many plants the pollen,
in order to accomplish the most
successful fertilization, must
come from another plant of the
same kind, not from the indi-
vidual which bears the ovules
that are being fertilized.

Pollen tubes begin to form
soon after pollen grains lodge
on the stigma. The time re-

FIG. 163. — Pollen Grains producing • -i <• , i i

Tubes, on stigma of a Lily. (Much quired for the process to begin
magnified.) varies in different kinds of

q, pollen grains ; t, pollen tubes ; p, , ...

of stigma ;c> canal or pas- plants, requiring in many cases
twenty-four hours or more. The
length of time needed for the
pollen tube to make its way
through the style to the ovary
depends upon the length of the

FIG. 164. -Pollen Grain of Snow- gtyle and other conditions. Jn
flake (Leucoium) producing a Pol- »
len Tube with Two Naked Genera- the CrOCUS, which has a Style

several inches long, the descent
takes from one to three days.

Finally the tube penetrates the opening at the apex of

sage running toward ovary.

FERTILIZATION

215

the ovule ra, in Fig. 165, reaches one of the cells shown
at e, and transfers a generative cell into this egg-cell. The
latter is thus enabled to
divide and grow rapidly
into an embryo. This
the cell does by forming
cell-walls and then in-
creasing by continued
subdivision, in much the
same way in which the
cells at the growing point
near the tip of the root, *•
or those of the cambium
layer, subdivide.1

227. Nature of the
Fertilizing Process. -
The necessary feature of
the process of fertiliza-
tion is the union of the
essential contents of two
cells to form a new one,
from which the future
plant is to spring. This
kind of union is found
to occur in many cryp-
togams (Chapters
XX- XXII), . resulting
in the production of
a spore capable of grow-
ing into a complete plant like that which produced it.

1 See Kerner and Oliver's Natural History of Plants, Vol. II, pp. 401-420.

FIG. 165. — Diagrammatic Representation of
Fertilization of an Ovule.

i, inner coating of ovule ; o, outer coating of
ovule; p, pollen tube, proceeding from one
of the pollen grains on the stigma ; c, the
place where the two coats of the ovule
blend. (The kind of ovule here shown is
inverted, its opening m being at the bottom,
and the stalk / adhering along one side of
the ovule.) a to e, embryo sac, full of pro-
toplasm ; a, so-called antipodal cells of em-
bryo sac ; n, central nucleus of the embryo
sac ; e, nucleated cells, one of which, the
egg-cell, receives the essential contents of
the pollen tube ; /, funiculus or stalk of
ovule ; m, opening into the ovule.

216 FOUNDATIONS OF BOTANY '

228, Number of Pollen Grains to Each Ovule. — Only
one pollen tube is necessary to fertilize each ovule, but
so many pollen grains are lost that plants produce many
more of them than of ovules. The ratio, however, varies
greatly. In the night-blooming cereus there are about
250,000 pollen grains for 30,000 ovules, or rather more
than 8 to 1, while in the common garden wistaria there
are about 7000 pollen grains to every ovule, and in Indian
corn, the cone-bearing evergreens, and a multitude of other
plants, many times more than 7000 to 1. These differences
depend upon the mode in which the pollen is carried from
the stamens to the pistil.

CHAPTER XVII
THE STUDY OF TYPICAL FRUITS

229, A Berry, the Tomato.1 — Study the external form of the
tomato, and make a sketch of it showing the persistent calyx and
peduncle.

Cut a cross-section at about the middle of the tomato. Note the
thickness of the epidermis (peel off a strip) and of the wall of the
ovary. Note the number, size, form, and contents of the cells of
the ovary. Observe the thickness and texture of the partitions
between the cells. Sketch.

Note the attachments of the seeds to the placentas and the gelati-
nous, slippery coating of each seed.

The tomato is a typical berry, but its structure presents fewer
points of interest than are found in some other fruits of the same
general character, so the student will do well to spend a little more
time on the examination of such fruits as the orange or the lemon.

230. A Hesperidium, the Lemon. — Procure a large lemon which
is not withered, if possible one which still shows the remains of the
calyx at the base of the fruit.

Note the color, general shape, surface, remains of the calyx,
knob at portion formerly occupied by the stigma. Sketch the fruit
about natural size. Examine the pitted surface of the rind with
the magnifying glass and sketch it. Kemove the bit of stem and
dried-up calyx from the base of the fruit ; observe, above the calyx,
the knob or disk on which the pistil stood. Note with the magni-
fying glass and count the minute whitish raised knobs at the bottom
of the saucer-shaped depression left by the removal of the disk.
What are they ?

1 Fresh tomatoes, not too ripe, are to be used, or those which have been kept
over from the previous summer in formalin solution. The very smallest
varieties, such as are often sold for preserving, are as good for study as the
larger kinds.

217

218 FOUNDATIONS OF BOTANY

Make a transverse section of the lemon, not more than a fifth of
the way down from the stigma end and note :

(1) The thick skin, pale yellow near the outside, white within.

(2) The more or less wedge-shaped divisions containing the juicy
pulp of the fruit. These are the matured cells of the ovary ; count
these.

(3) The thin partition between the cells.

(4) The central column or axis of white pithy tissue.

(5) The location and attachment of any seeds that may be
encountered in the section.

Make a sketch to illustrate these points, comparing it with
Fig. 171.

Study the section with the magnifying glass and note the little
spherical reservoirs near the outer part of the skin, which contain the
oil of lemon which gives to lemon peel its characteristic smell and
taste. Cut with the razor a thin slice from the surface of a lemon
peel, some distance below the section, and at once examine the
freshly cut surface with a magnifying glass to see the reservoirs,
still containing oil, which, however, soon evaporates. On the cut
surface of the pulp (in the original cross-section) note the tubes in
which the juice is contained. These tubes are not cells, but their
walls are built of cells. Cut a fresh section across the lemon, about
midway of its length and sketch it, bringing out the same points
which were shown in the previous one. The fact that the number
of ovary cells in the fruit corresponds with the number of minute
knobs in the depression at its base is due to the fact that these
knobs mark the points at which fibro-vascular bundles passed from
the peduncle into the cells of the fruit, carrying the sap by which
the growth of the latter was maintained.

Note the toughness and thickness of the seed-coats. Taste the
kernel of the seed.

Cut a very thin slice from the surface of the skin, mount in
water, and examine with a medium power of the microscope.
Sketch the cellular structure shown and compare it with the sketch
of the corky layer of the bark of the potato tuber.

Of what use to the fruit is a corky layer in the skin? (See Sect.
453 for further questions.)

THE STUDY OF TYPICAL FRUITS 219

231. A Legume, the Bean-Pod.1 — Lay the pod flat on the table
and make a sketch of it, about natural size. Label stigma, style,
ovary, calyx, peduncle.

Make a longitudinal section of the pod, at right angles to the
plane in which it lay as first sketched, and make a sketch of the
section, showing the partially developed seeds, the cavities in which
they lie, and the solid portion of the pod between each bean and
the next.

Split another pod, so as to leave all the beans lying undisturbed
on one-half of it and sketch that half, showing the beans lying in
their natural position and the funiculus or stalk by which each is
attached to the placenta ; compare Fig. 271.

Make a cross-section of another pod, through one of the beans,
sketch the section, and label the placenta (formed by the united
edges of the pistil leaf) and the midrib of the pistil leaf.

Break off sections of the pod and determine, by observing where
the most stringy portions are found, where the nbro-vascular bundles
are most numerous.

Examine some ripe pods of the preceding year,2 and notice where
the dehiscence, or splitting open of the pods, occurs, whether down
the placental edge, ventral suture, the other edge, dorsal suture, or
both.

232. An Akene, the Fruit of Dock. — Hold in the forceps a ripe
fruit of any of the common kinds of dock,3 and examine with the
magnifying glass. Note the three dry, veiny, membranaceous sepals
by which the fruit is enclosed. On the outside of one or more of
the sepals is found a tubercle or thickened appendage which looks
like a little seed or grain. Cut off the tubercles from several of the
fruits, put these, with some uninjured ones, to float in a pan of
water, and watch their behavior for several hours. What is appar-
ently the use of the tubercle ?

1 Any species of bean (Phaseolus) will answer for this study. Specimens
in the condition known at the markets as " shell-beans " would be best, but
these are not obtainable in spring. Ordinary " string-beans " will do.

2 Which may be passed round for that purpose. They should have been
saved and dried the preceding autumn.

8 Rumex crispus, R. obtusifolius, or R. verticillatus. This should have
been gathered and dried the preceding summer.

220 FOUNDATIONS OF BOTANY

Of what use are the sepals, after drying up ? Why do the fruits
cling to the plant long after ripening?

Carefully remove the sepals and examine the fruit within them.
What is its color, size, and shape? Make a sketch of it as seen with
the magnifying glass. Note the three tufted stigmas, attached by
slender threads to the apex of the fruit. What does their tufted
shape indicate ?

What evidence is there that this seed-like fruit is not really a
seed?

Make a cross-section of a fruit and notice whether the wall of
the ovary can be seen, distinct from the seed-coats. Compare the
dock fruit in this respect with the fruit of the buttercup, shown in
Fig. 166. Such a fruit as either of these is called an akene.

CHAPTER XVIII
THE FRUIT1

233, What constitutes a Fruit. — It is not easy to make
a short and simple definition of what botanists mean by
the teim fruit. It has very little to do with the popular
use of the word. Briefly stated, the definition may be
given as follows : The fruit consists of the matured ovary
and contents, together with any intimately connected parts.
Botanically speaking, the bur of beggar's ticks (Fig. 273),
the three-cornered grain of buckwheat, or such true grains
as wheat and oats, are as much fruits as is an apple or a
peach.

The style or stigma sometimes remains as an important
part of the fruit in the shape of a hook, as in the common
hooked crowfoot ; or in the shape of a plumed appendage,
as in the virgin's bower, often called wild hops. The
calyx may develop hooks, as in the agrimony, or plumes,
as in the thistle, the dandelion, lettuce, and many other
familiar plants. In the apple, pear, and very many ber-
ries, the calyx becomes enlarged and pulpy, often consti-
tuting the main bulk of the mature fruit. The receptacle
not infrequently, as in the apple, forms a more or less
important part of the fruit.

234. Indehiscent and Dehiscent Fruits All of the

fruits considered in the next three sections are indehiscent,

1 See Gray's Structural Botany, Chapter VII, also Kerner and Oliver's
Natural History of Plants, Vol. II, pp. 427-438.
• 221

222

FOUNDATIONS OF BOTANY

FIG. 166. — Akenes of a Buttercup.

A, head of akenes ; B, section of a single

akene (magnified) ; a, seed.

that is, they remain closed after ripening. Dehiscent
fruits when ripe open in order to discharge their seeds.

The three classes which im-
mediately follow Sect. 237
belong to this division.

235. The Akene. — The
one-celled and one-seeded
pistils of the buttercup,
strawberry, and many other
flowers, ripen into a little
fruit called an akene (Fig.
166). Such fruits, from
their small size, their dry
consistency, and the fact that they never open, are usually
taken for seeds by those who are not botanists.

In the group of plants to which the daisy, the sunflower,
and the dandelion belong, the akenes consist of the ovary
and the adherent calyx tube. The limb of the calyx is
borne on the summit of many akenes, sometimes in the form
of teeth, sometimes as a tuft
of hairs or bristles (Fig. 267). ^

236. The Grain. — Grains,
such as corn, wheat, oats, bar-
ley, rice, and so on, have the
interior of the ovary com-
pletely filled by the seed, and
the seed-coats and the wall of
the ovary are firmly united, as
shown in Fig. 6.

237. The Nut. — A nut (Fig. 167) is larger than an
akene, usually has a harder shell, and commonly contains

FIG. 167. — Chestnuts.

THE FRUIT

223

a seed which springs from a single ovule of one cell of a
compound ovary, which develops at the expense of all the
other ovules. The chestnut-bur is a kind of involucre,
and so is the acorn-cup. The name
nut is often incorrectly applied in
popular language; for example, the
so-called Brazil-nut is really a large
seed with a very hard testa.

238. The Follicle. — One-celled,
simple pistils, like those of the marsh
marigold, the columbine, and a good
many other plants, often produce a
FIG. IBS. -Group of Fom- fruit which dehisces along a single
cies and a single Foiiicie suture, usually the ventral one. Such

of the Monkshood. J

a fruit is called a follicle (Fig. 168).

239. The Legume. — A legume is a one-celled pod,
formed by the maturing of a simple pistil, which dehisces
along both of its sutures, as already seen in the case of
the bean pod, and illus-
trated in Fig. 271.

240. The Capsule. —
The dehiscent fruit
formed by the ripening
of a compound pistil is
called a capsule. Such
a fruit may be one-
celled, as in the linear
pod of the celandine
(Fig. 271), or several-
celled, as in the fruit of the poppy, the morning-glory,
and the jimson weed (Fig. 271).

FIG. 169. — Winged Fruits.
I, elm ; H, maple.

224 FOUNDATIONS OF BOTANY

241. Dry Fruits and Fleshy Fruits. — In all the cases
discussed or described in Sects. 238-240, the wall of the
ovary (and the adherent calyx when present) ripen into
tissues which are somewhat hard and dry. Often, how-
ever, these parts become developed into a juicy or fleshy
mass by which the seed is surrounded ; hence a general
division of fruits into dry fruits and fleshy fruits.

242, The Stone-Fruit. — In the peach, apricot, plum, and
cherry, the pericarp or wall of the ovary, during the proc-
ess of ripening, becomes con-
verted into two kinds of tissue,
the outer portion pulpy and
edible, the inner portion of.
almost stony hardness. In
common language the hard-
ened inner layer of the peri-
carp, enclosing the seed, is
called the stone (Fig. 170),

FIG. 170.— Peach. Longitudinal hence the name stone-fruits.

243. The Pome.— The fruit

of the apple, pear, and quince is called a pome. It con-
sists of a several-celled ovary, — the seeds and the tough
membrane surrounding them in the core, — enclosed by a
fleshy, edible portion which makes up the main bulk of
the fruit and is formed from the much-thickened calyx,
with sometimes an enlarged receptacle. In the apple and
the pear much of the fruit is receptacle.

244. The Pepo or Gourd-Fruit. — In the squash, pump-
kin, and cucumber, the ripened ovary, together with the
thickened adherent calyx, makes up a peculiar fruit (with
a firm outer rind) known as the pepo. The relative bulk

THE FRUIT

225

of enlarged calyx and of ovary in such fruits is not always
the same.

How does the amount of material derived from fleshy
and thickened placentae in the squash compare with that
in the watermelon ?

245. The Berry. — The berry proper, such as the
tomato, grape, persimmon, gooseberry, currant, and so on,
consists of a rather thin- £„

skinned, one- to several-
celled, fleshy ovary and its
contents. In the first three

cases above mentioned the

" --S

FIG. 171. *— Cross-Section of an Orange.
a, axis of fruit with dots showing cut-off
ends of flbro-vascular bundles ; p, parti-
tion between cells of ovary ; S, seed ;
c, cell of ovary, filled with a pulp com-
posed of irregular tubes, full of juice ;
o, oil reservoirs near outer surface of
rind ; e, corky layer of epidermis.

- The raspberry, blackberry

calyx forms no part of the
fruit, but it does in the last
two, and in a great number
of berries.

The gourd-fruit and the
hesperidium, such as the
orange (Fig. 171), lemon,
and lime, are merely de-
cided modifications of the
berry proper.

246. Aggregate Fruits.
(Fig. 172), and similar fruits consist of many carpels, each
of which ripens into a part of a compound mass, which,
for a time at least, clings to the receptacle. The whole is
called an aggregate fruit.

To which one of the preceding classes does each unit of
a blackberry or of a raspberry belong ?

Wl>at is the most important difference in structure
between a fully ripened raspberry and a blackberry ?

226 FOUNDATIONS OF BOTANY

247. Accessory Fruits and Multiple Fruits. — Not infre-
quently, as in the strawberry (Fig. 172), the main bulk of
the so-called fruit consists neither of the ripened ovary
nor its appendages. Such a combination is called an
accessory fruit.

Examine with a magnifying glass the surface of a small, unripe
strawberry, then that of a ripe one, and finally a section of a ripe
one, and decide where the separate fruits of the strawberry are found,
what kind of fruits they are, and of what the main bulk of the straw-
berry consists.

The fruits of two or more separate flowers may blend
into a single mass, which is known as a multiple fruit.
Perhaps the best-known edible examples of this are the

i ii in

FIG. 172.— I, Strawberry ; II, Raspberry ; III, Mulberry.

mulberry (Fig. 172) and the pineapple. The last-named
fruit is an excellent instance of the seedless condition
which not infrequently results from long-continued culti-
vation.

248. Summary. — The student may find it easier to
retain what knowledge he has gained in regard to fruits if
he copies the following synopsis of the classification of
fruits, and gives an example of each kind.

THE FRUIT

227

Fruits

r Simple.

Composition J Aggregate.
I Accessory.

[Multiple.

r f1-

Fleshy J 2.

[s.

Texture

Stone

f1'

Dry |j

14.

Indehiscent ^ 2.

Mode of

I3-

disseminating seed

fl.

Dehiscent J 2.
3.

CHAPTER XIX
THE CLASSIFICATION OF PLANTS1

249. Natural Groups of Plants. — One does not need to
be a botanist in order to recognize the fact that plants
naturally fall into groups which resemble each other pretty
closely, that these groups may be combined into larger
ones the members of which are somewhat alike, and so on.
For example, all the bulb-forming spring buttercups 2 which
grow in a particular field may be so much alike in leaf,
flower, and fruit that the differences are hardly worth
mentioning. The tall summer buttercups 3 resemble each
other closely, but are decidedly different from the bulbous
spring-flowering kind, and yet are enough like the latter
to be ranked with them as buttercups. The yellow
water-buttercups4 resemble in their flowers the two
kinds above mentioned, but differ from them greatly in
habit of growth and in foliage, while still another, a
very small-flowered kind,5 might fail to be recognized
as a buttercup at all.

The marsh marigold, the hepatica, the rue anemone,
and the anemone all have a family resemblance to butter-
cups,6 and the various anemones by themselves form
another group like that of the buttercups.

1 See Warming and Potter's Systematic Botany, Strasburger, Noll, Schenk,
and Schimper's Text-Book of Botany, Part II, or Kerner and Oliver, Vol. II,
pp. 616-790. 2 R. bulbosus. 3 R. acris. 4 R. multifidus. 5 R. abortive,

6 Fresh specimens or herbarium specimens will show this.

228

THE CLASSIFICATION OF PLANTS 229

250. Genus and Species. — Such a group as that of the
buttercups is called a genus (plural genera), while the
various kinds of buttercups of which it is composed are
called species. The scientific name of a plant is that of the
genus followed by that of the species. The generic name
begins with a capital, the specific does not, unless it is a
substantive. After the name comes the abbreviation for
the name of the botanist who is authority for it; thus the
common elder is Sambucus canadensis, L., L. standing for
Linnseus. Familiar examples of genera are the Violet
genus, the Rose genus, the Clover genus, the Golden-rod
genus, the Oak genus. The number of species in a genus
is very various, — the Kentucky Coffee-tree genus con-
tains only one species, while the Golden-rod genus com-
prises more than forty species in the northeastern United
States alone.

251. Hybrids If the pollen of a plant of one species

is placed on the stigma of a plant of the same genus but a
different species, no fertilization will usually occur. In a
large number of cases, however, the pistil will be ferti-
lized, and the resulting seed will often produce a plant
intermediate between the two parent forms. This proc-
ess is called hybridization, and the resulting plant a
hybrid. Many hybrid oaks have been found to occur
in a state of nature, and hybrid forms of grapes, orchids,
and other cultivated plants, are produced by horticul-
turists at will.

252. Varieties. — Oftentimes it is desirable to describe
and give names to subdivisions of species. All the culti-
vated kinds of apple are reckoned as belonging to one spe-
cies, but it is convenient to designate such varieties as the

230 FOUNDATIONS OF BOTANY

Baldwin, the Bellflower, the Rambo, the Gravenstein, the
Northern Spy, and so on. Very commonly varieties do
not, as horticulturists say, " come ;true," that is to say, the
seeds of any particular variety of apple not only are not
sure to produce that variety, but they are nearly sure to
produce a great number of widely different sorts. Varie-
ties which will reproduce themselves from the seed, such
as pop-corn, sweet corn, flint-corn, and so on, are called
races.

Only long and careful study of plants themselves and
of the principles of classification will enable any one to
decide on the limits of the variety, species, or genus, that
is, to determine what plants shall be included in a given
group and what ones shall be classed elsewhere.

253. Order or Family. — Genera which resemble each
other somewhat closely, like those discussed in Sect. 249,
are classed together in one order or family. The particu-
lar genera above mentioned, together with a large number
of others, combine to make up the Crowfoot family. In
determining the classification of plants most points of
structure are important, but the characteristics of the
flower and fruit outrank others because they are more
constant, since they vary less rapidly than the characteris-
tics of roots, stems, and leaves do under changed condi-
tions of soil, climate, or other surrounding circumstances.
Mere size or habit of growth has nothing to do with the
matter, so the botanist finds no difficulty in recognizing
the strawberry plant and the apple tree as members of
the same family.

This family affords excellent illustrations of the mean-
ing of the terms genus, species, and so on. Put in a

THE CLASSIFICATION OF PLANTS

231

tabular form, some of the subdivisions of the Rose family
are as follows :

j Peach species (many varieties).

Plum genus J Garden Plum sPecies (many varieties).

Wild black cherry species.
I Garden red cherry species (many varieties).

I Dwarf wild rose
species.
Sweet-brier species.

T ,. . f Tea variety.

India rose species 4 n .

Pear genus

Damask rose species.

Pear species

Apple species

Pompon variety, etc.

f Seckel variety.
•< Bartlett variety.
^ Sheldon variety, etc.

Baldwin variety.
Greening variety.
Bellflower variety.
Northern Spy variety,
etc.

254, Grouping of Families. — Families are assembled
into classes, and these again into larger groups. The
details of the entire plan of classification are too compli-
cated for any but professional botanists to master, but an
outline of the scheme may be given in small space.

The entire vegetable kingdom is divided into two great
divisions, the first consisting of cryptogams or spore-plants,
the second of phanerogams or seed-plants. Here the rela-
tions of the various subdivisions may best be shown by a
table.1

1 This is, of course, only for consultation, not to be committed to memory.

232

FOUNDATIONS OF BOTANY

•a

^
fl "** V

oT "S

«« P< «S»

E the Vegetable Kingdom.

Myxogasteres, Common slime

Schizomycetes, Bacteria.

Schizophycece, Fission-plants.
, Bacillariales, Diatoms.

Conjugates, Desmids and pon
Chlorophycece, Green algae.
, Phceophycece, Brown algae.

, Rhodophycece, Red algae.
, Phycomycetes, Moulds, etc.

'Basidiomycetes, Mildews, rust
, Ascomycetes, Yeasts, truffles,

ca oj s°
8^ ^ 2
^ g g

<1 PH S

-4^

S
1

<sj

tf •

, Hepaticce, Liverworts.
, Musci, True mosses.

. Filicales, Ferns.
. Equisetales, Scouring rushes.

. Lycopodiales, Club mosses.

laced in a subgroup known as alga
)group, fungi.

CM CO

•^ lO CD

t» oo

O5 O

r-l (N

T-t C^

•— &

7/5

5 1

c M

i_5 J^

CO ^

„

-2 S

<J S

V y

"8 -3

0 °

v —

02 fl

O> T-

r-H

t>5 ®

fe ft.

•s

GROUP I

XOTHALLOPHYl

plasmodial plan

HALLOPHYTE8 (

tfes* cellular cry^

GROUP III
fOPHYTES or mi
like plants

GROUP IV

'ERIDOPHYTES

\
1

ive of the thallop
inclus

»o

[

H C

«9i

I-H

;

THE CLASSIFICATION OF PLANTS

233

DIVISION II

PHANEROGAMS OR

SEED-PLANTS

CLASS I

GYMNOSPERMS or seed-plants with naked ova-
ries, such as pines, spruces, cedars, and many
other evergreen trees.

f SUBCLASS- I

CLASS II
ANGIOSPERMS or

seed-plants with
closed ovaries

MONOCOTYLEDONOUS

PLANTS

SUBCLASS II
DICOTYLEDONOUS

PLANTS

256, The Groups of Cryptogams. — The student is not
to suppose that the arrangement of cryptogams into the
four great groups given in the preceding table is the only
way in which they could be classed. It is simply one
way of dividing up the enormous number of spore-bearing
plants into sections, each designated by marked character-
istics of its own. But the amount of difference between
one group and another is not always necessarily the same.
The pteridophytes and the bryophytes resemble each
other much more closely than the latter do the thallo-
phytes, while the myxothallophytes are but little like other
plants and it is extremely probable that they are really
animals.

The classes given in the table do not embrace all known
cryptogams, but only those of which one or more repre-
sentatives are described or designated for study in this
book. Lichens in one sense hardly form a class, but it is
most convenient to assemble them under a head by them-
selves, on account of their extraordinary mode of life, a
partnership between algae and fungi.

257. The Classes of Seed-Plants. — The gymnosperms
are much less highly developed than other seed-plants.

234 FOUNDATIONS OF BOTANY

The angiosperms constitute the great majority of seed-
plants (or, as they have been more commonly called,
flowering plants). Only one family of gymnosperms (the
Coniferce) is described in Part III of this book, though
there are other families of great interest to the botanist,
but with no representatives growing wild in the Northern
United States.

When people who are not botanists speak of plants
they nearly always mean angiosperms. This class is more
interesting to people at large than any other, not only on
account of the comparatively large size and the con-
spicuousness of the members of many families, but also
on account of the attractiveness of the flowers and fruit
of many. Almost all of the book which precedes the
present chapter (except Chapter XII) has been occupied
with seed-plants.

Seed-plants of both classes frequently offer striking
examples of adaptation to the conditions under which
they live, and these adaptations have lately received much
study, and are now treated as a separate department of
botany (see Part II).

CHAPTER XX
TYPES OF CRYPTOGAMS; THALLOPHYTES

258. The Group Thallophytes. — Under this head are
classed all the multitude of cryptogams which have a
plant-body without true roots, stems, or leaves. Such a
plant-body is called a thallus. In its simplest form it con-
sists of a portion of protoplasm not enclosed in a cell-wall
and without much of any physiological division of labor
among its parts (Fig. 125). Only a little less simple are
such enclosed cells as that of Pleurococcus (Sect. 278) or
one of the segments of Oscillatoria (Sect. 268). The most
complex thallophytes, such as the higher algse and fungi,
have parts definitely set aside for absorption of food and
for reproduction. The latter is sometimes accomplished
by more than one process and is occasionally aided by
some provision for scattering the reproductive bodies or
spores about when they are mature.

259. Spores. — Before beginning the study of spore-
plants it is well for the student to know what a spore is.
A spore is a cell which becomes free and capable of develop-
ing into a new plant. Spores are produced in one of two
ways : either asexually, from the protoplasm of some part
of the plant (often a specialized spore-producing portion),
or sexually, by the combination of two masses of proto-
plasm, from two separate plants, or from different parts of
the same plant.

235

236 FOUNDATIONS OF BOTANY

Asexually produced spores are sometimes formed, each
by the condensation of the protoplasm of a single cell, as
shown in Fig. 174, E. They are also formed by the con-
tents of spore-cases breaking up into many spores (Fig.
173, B\ Fig. 210, D). Spores are sometimes produced by
the spontaneous division of a mass of protoplasm into a
small definite number of segments (Fig. 188, t). Spores
which have the power of moving (swimming) freely are
known as zoo spores (Fig. 179, B).

Sexually produced spores are formed in many ways.
One of the simplest modes is that shown in Fig. 178,
resulting in zygospores. Other methods are illustrated in
Figs. 185 and 187.1

THE STUDY OF SLIME MOULDS 2

260, Occurrence. — Slime moulds occur in greenhouses, in tan-
yards, or on old logs arid decaying leaves in woods. They may be
cultivated in the laboratory.

They have been described in their vegetative condition on page 179.

261, Examination with the Magnifying Glass. — Stemonitis is one
of the most available genera to illustrate the fruiting of slime moulds.
At maturity the motile protoplasm of the vegetative stage quickly
transforms itself into numerous sporangia or spore-cases with dust-
like spores. With the naked eye and with a magnifying glass note
the color, form, and feathery appearance of the spore-case of Stemo-
nitis. The outer wall disappears at an early stage, leaving only an
inner structure and spores. Sketch the general outline under a
magnifying glass.

262, Examination with the Microscope. — With a low power of
the microscope sketch the network of branching hairs which com-
pose the structure of the sporangium. Note the presence or absence

1 See Vine's Student's Text-Book of Botany, pp. 68-71.

2 This should logically precede Sect. 258.

TYPES OF CRYPTOGAMS; THALLOPHYTES

237

of a central column. Have any of the branches free tips ? With a
power of 250 or more examine the spores. A much higher power
may be used to advantage. Describe the surface of the spore.

THE STUDY OF BACTERIA

263. Occurrence. — " Bacteria may occur anywhere but not every-
where." In water, air, soil, and almost any organic substance, living

FIG. 173. — Spore-Cases of Slime Moulds.

A, a group of spore-cases of Arcyria; £, a spore-case of TricMa, bursting open
and exposing its spores to the wind, x 20 ; C, threads of the same, with spores
between them, x 250.

or dead, some species of plant belonging to the group Bacteria may
occur. A small bunch of hay placed in a tumbler of water will, at a
suitable temperature, yield an abundant crop in a few days or hours.
Raw peas or beans soaked for a week or two in water in a warm
place will afford a plentiful supply.

264. Cultures. — Pure cultures of bacteria are commonly made in
some preparation of gelatine in sterilized test-tubes. Boiled potatoes
serve a good purpose for simple (but usually not pure) cultures.

Select a few small roundish potatoes with skins entire and boil
in water for a sufficient time to cook them through. Cut them in
halves with a knife well scalded or sterilized, i.e., freed from all living

238 FOUNDATIONS OF BOTANY

organisms in a flame, and lay each on a saucer, with cut surface up,
covering each with a glass tumbler. The tumblers and saucers
should be well scalded or kept in boiling water for half an hour and
used without wiping. Sterilization may be improved by baking
them in an oven for an hour.

265. Inoculation. — The culture media prepared as above may
now be inoculated. Uncover them only when necessary and quickly
replace the cover. Scrape a little material from the teeth, tongue,
kitchen sink, floor of house or schoolroom, or any other place you
may desire to investigate. With the point of a knife blade or a
needle sterilized in a flame, inoculate a particle of the material to be
cultivated into the surface of one of the potatoes. Several cultures

D E

FIG. 174. — Bacteria stained to show Cilia.

A, Bacillus subtilis ; B, Bacillus typhi (the bacillus of typhoid fever) ; C, Bacillus
tetani (the bacillus which causes lockjaw) ; D, Spirillum undula; E, Bacillus
tetani forming spores. (All five are magnified 1000 diameters.)

may be made in this way and one or more left uninoculated as
checks. Another may be left uncovered in the air for half an hour.
Others may be made with uncovered potatoes. Number each culture
and keep a numbered record.

Keep watch of the cultures, looking at them daily or oftener. As
soon as any change is noticed on the surface of a culture, make a
descriptive note of it and continue to record the changes which are
seen. Note the color of the areas of growth, their size, outline, ele-
vation above the surface, and any indications of wateriness. Any
growth showing peculiar colors or other characters of special inter-
est may be inoculated into freshly prepared culture media, using
any additional precautions that are practicable to guard against
contamination.

TYPES OF CKYPTOGAMS; THALLOPHYTES 239

266. Microscopic Examination. — Examine some of the cultures.
Place a particle of the growth on a slide, dilute it with -a drop of
clear water, and place a cover-glass over it. Examine with^ the
highest obtainable power of the microscope, at least £ iu. objective.
Note the forms and movements, also the sizes if practicable, of any
bacteria that are found.

THE STUDY OF OSCILLATORIA 1

267. Occurrence. — Oscillatoria may occur floating in stagnant
water or on damp soil in ditches, roadsides, dooryards, paths, or
pots in greenhouses. Other nearly related plants occur on surfaces
of ponds sometimes covering considerable areas or adhering in small
spheres to submerged vegetation. Algse of this class are particu-
larly noxious in water supplies, as they partake of the nature of
bacteria, to which they are related.

268. Examination with the Microscope. — After washing a particle
of Oscillatoria material in a drop of water to remove as much of the
earth as possible, place it in a clean drop of water, pull to shreds
with needles, cover, and examine under a power of 200 or more
diameters.

Note the color and compare it with chlorophyll green.

The filament is not one plant, but each of the cells which com-
pose it is one plant. They are packed together in the filament like
coins and sometimes may be found separating singly. The usual
mode of reproduction is by the separation of a number of adhering
cells as a short filament from one end of a longer one, and this
increases in length by the dividing of its individual cells.

269. Movement. — At ordinary temperatures, favorable to growth,
movement may be observed in the filaments. Describe the move-
ment. What has it to do with the name of the plant ?

1 A genus of the class Schizophycese.

240

FOUNDATIONS OF BOTANY

THE STUDY OF DIATOMS

270. Occurrence. — Diatoms of different species may be found in
sediment in water in various kinds of places or mixed with or

adhering to fresh-water or ma-
rine algae, in ponds and ditches
or on sand or earth at the
bottom of clear brooks. In the
last place they may be detected
with the eye, forming a yellow-
ish coloring. They may often
be obtained by straining hy-
drant water. Where diatoms
have been very abundant their
remains sometimes form beds
of rock, and fossil diatoms
compose some of the polishing
powders of commerce.

271. Microscopical Examina-
tion of Diatoms. — Place a drop
of water containing diatoms on
a slide and put a cover-glass
over it. Examine with a power
of 200 or more diameters. Dia-
toms occur singly/ resembling
triangles, wheels, boats, rods-,
and a great variety of other
forms (Fig. 176), or adhering
in long bands, as spokes of a
wheel, etc. The boat-shaped
kinds are among the common-
est. The color of the contents
is yellowish. The cell-wall is
encrusted with a shell of silica
whose surface is covered with beautiful markings, dots or lines,
which are conspicuous in some species, in others so minute that the
most powerful microscopes are required to detect them. By boiling

FlG. 175. — Schlzophycex.
A, a filament of Calothrix, reproducing by
hormogonia, h, segmented portions which
escape from the sheath of the filament ;
B, Rlvularla. (Both A and B greatly
magnified.)

TYPES OF CRYPTOGAMS ; THALLOPHYTES

241

in nitric acid, the cellulose wall and its contents may be destroyed
and the markings of the siliceous shell more easily observed. Each
diatom consists of a single cell.

272. Movements of Diatoms. — Living diatoms exhibit a peculiar
power of movement. In the boat-shaped species the movement is
much like that of a row-boat, forward or backward.

THE STUDY OF SPIROGYRA

273. Occurrence. — Spirogyra, one of the plants commonly known
as pond-scum, or " frog-spit," occurs widely distributed throughout
the country in ponds, springs,

and clear streams. It is of a
green or yellowish-green color,
and in sunny weather usually
floats on or near the surface of
the water, buoyed up by the
numerous oxygen bubbles which
it sets free. It may be found
flourishing in unfrozen springs,
even in midwinter.

274. Examination with the
Magnifying Glass.1 — Float a
little of the material in a white
plate, using just water enough
to cover th6 bottom of the latter.
Study with the magnifying glass
and note the green color of the
threads and their great length
as compared with their thick-
ness. Are all the filaments about

FIG. 176. — A Group of Diatoms.

A, Achnanthes; B, Cocconema;
C, Meridian; D, Pleurosigma.

equal to each other in diameter ?

Handle a mass of the material and describe how it feels between
the fingers.

275. Examination with the Microscope. — Mount in water under
a large cover-glass and examine first with a power of about 100

1 Consult Huxley's Biology and Spalding's Introduction to Botany.

242

FOUNDATIONS OF BOTANY

diameters, then with a power of 200 diameters or more. Note the
structure of the filaments. Of what is each made up? Compare
with the structure of Oscillatoria.

Move the slide so as to trace the whole length of several filaments,
and, if the unbroken end of one can be found, study and sketch it.

Study with the higher power a single
cell of one of the larger filaments and
ascertain the details of structure. Try
to discover, by focusing, the exact shape
of the cell. How do you know that
the cells are riot flat? Count the bands
of chlorophyll. The number of bands
is an important characteristic in dis-
tinguishing one species from another.
Run in five-per-cent salt solution at
one edge of the cover-glass (withdraw-
ing water from the other edge with a
bit of blotting paper). If any change
in the appearance of the cell becomes
evident, make a sketch to show it.
What has happened to the cell-con-
tents? Explain the cause of the
change by reference to what you know
of osmose.

On a freshly mounted slide run
under the cover-glass iodine solution,
a little at a time, and note its action
on the nucleus. Is any starch shown
to be present? If so, just how is it
distributed through the cell?

276. Reproduction of Spirogyra. —
The reproductive process in Spirogyra
is of two kinds, the simplest being a process of fission, or cell-
division. The nucleus undergoes a very complicated series of
transformations, which result in the division of the protoplasmic
contents of a cell into two independent portions, each of which is
at length surrounded by a complete cell-wall of its own. In Fig. 176

FIG. 177. — Process of Cell-Multi-
plication in a Species of Pond-
Scum. (Considerably magnified.)

A, portion of a filament partly
separated at a and completely
so at b ; B, separation nearly
completed, a new partition of
cellulose formed at a; C,
another portion more magni-
fied, showing mucous covering
d, general cell-wall c, and a
delicate membrane a, which
covers the cell-contents b.

TYPES OF CRYPTOGAMS; THALLOPHYTES

243

the division of the protoplasm and formation of a partition of
cellulose in a kind of pond-scum are shawn, but the nucleus and its
changes are not represented.

Another kind of reproduction, namely by conjugation, is found in
Spirogyra. This process in its simplest form is found in such
unicellular plants as the desmids
(Fig. 178). Two cells (apparently
precisely alike) come in contact,
undergo a thinning-down or absorp-
tive process in the cell-walls at the
point of contact, and finally blend
their protoplasmic cell-contents, as
shown in the figure, to form a mass
known as a spore, or more accu-
rately a zygospore, from which, after

FIG. 178.— Conjugation of Cells of Green Algae. (Much magnified.)

I. Conjugation of Desmids. A, a single plant in its ordinary condition; B, empty
cell-wall of another individual ; C, conjugation of two individuals to form a
spore- by union of their cell-contents.

II. Conjugation of Spirogyra. A, two filaments of Spirogyra side by side, with
the contents of adjacent cells uniting to form spores, z. At the bottom of the
figure the process is shown as beginning at the top as completed, and the cells
of one filament emptied ; £, a single filament of another kind of Spirogyra,
containing two spores, one lettered z. (A magnified 240 diameters, B 150
diameters.)

a period of rest, a new individual develops. In Spirogyra each
cell of the filament appears to be an individual and can conjugate
like the one-celled desmids. It is not easy to watch the process,
since the spore-formation takes place at night. It is possible,

244

FOUNDATIONS OF BOTANY

however, to retard the occurrence of conjugation by leaving the
Spirogyra filaments in very cold water over night, and in this way
the successive steps of the conjugating process may be studied by
daylight. In such ways the series of phenomena shown in Fig.
178, II, has been accurately followed. If the student cannot follow
these operations under the microscope, he may, at least, by looking
over the yellower portions of a mass of Spirogyra find threads con-
taining fully formed zygospores, like those shown in B, Fig. 178.

THE STUDY OF PLEUROCOCCUS

277. Occurrence. — Pleurococcus may be found on old fences,
roofs, and many similar places, particularly on the bark of the north
side of trees. The individual plants cannot be detected by the naked
eye, but when grouped in masses they form a powdery-green covering
over indefinite areas of bark. Plenty are seen where it is moist.

278. Microscopical Examination of Pleurococcus. — Scrape a minute
quantity of Pleurococcus from a specimen on bark, place it in a drop
of water on a slide, distributing it slightly in the water, lay on it

a cover-glass and ex-
amine with a power of
200 or more diameters.
Sketch with the cam-
era lucida one of the
largest cells, some of
intermediate size, and
one of the smallest,
beside several divisions
of the stage microm-
eter.

Note the clearly de-
fined cell-wall of cel-
lulose, enclosing the
protoplasmic contents,
usually green through-
Do any cells show a nucleus like that in Fig. 179, A ?

FlG. 179. — Two Cells of Protococcus.
(Greatly magnified.)

A, a spherical cell of the still form ; B, a motile cell
with its protoplasm enclosed in a loose cell-wall and
provided with two cilia.

out.

Test the cells with iodine solution for starch.

TYPES OF CRYPTOGAMS; THALLOPHYTES 245

"Note that in reproduction the cell-contents in many individuals
has divided into two parts which become separated from each other
by a cellulose partition. Each of these again divides, and the proc-
ess continues until thirty-two or more cells may be found in one
mass or they may fall apart at an earlier stage.

279. Nutrition of Pleurococcus. — Pleurococcus can nourish only
with an abundance of light and moisture. In daylight it can absorb
carbon dioxide and fix carbon (giving off the oxygen at the same
time as bubbles of oxygen) and can assimilate mineral substances.
It is a capital example of an individual cell capable of independent
existence.

280. Motile Forms. — No motile form is known in Pleurococcus.
Hcematoccus, often known as Protococcus (Fig. 179), is a better object
for study than Pleurococcus. It may sometimes be found in water
of stagnant pools, particularly those which contain the drainage of
barnyards or manure-heaps, in mud at the bottom of eaves-troughs,
in barrels containing rain-water, or in water standing in cavities in
logs or stumps. Its presence is indicated by a greenish or some-
times by a reddish color. It is sometimes found in an actively
swimming condition, in which case each cell is called a zoospore.

THE STUDY OF VAlJCHERIA

281. Occurrence. — Species of Vaucheria are found in ponds,
streams, and pools, immersed or floating like Spirogyra and at all
seasons may be sought in greenhouses, where they grow on the moist
earth of beds and pots, forming a green felt.

282. Examination with the Magnifying Glass. — The magnifying
glass will show the growth of Vaucheria to consist of numerous
green filaments similar to those of Spirogyra. Select a srnall portion
and spread out the filaments carefully in a drop of water on a slide.
Does the -glass reveal any indications of cross-partitions, of branch-
ing, or of fruiting organs as short lateral branches ? Does it show
the form or arrangement of the green coloring matter?

283. Examination with the Microscope. — Prepare as directed
for the magnifying glass and place a cover-glass over the prepara-
tion, with sufficient water. With the lowest power observe the

246

FOUNDATIONS OF BOTANY

continuity of the cell-cavity and (in young plants growing on soil)
search for root-like portions, in those growing in water for branch-
ing portions, and fruiting organs in the form of swellings or short
lateral branches.

With a power of about thirty to sixty diameters sketch a selected
plant of moderate extent as. nearly complete as possible or else

FIG. 180. — Vaucheria synandra.

A, a filament with archegonia and antheridia (considerably magnified) ; B, part
of same much more highly magnified ; o, oogonium ; a, antheridium ; C, a
later stage of B ; Z>, end of a filament with a zoospore, z, escaping (highly
magnified).

sketch a portion showing the branching and a root-like portion.
Note and indicate the absence or presence and arrangement of
chlorophyll. Can Vaucheria probably use carbon dioxide?

284. Reproduction in Vaucheria. — Make an outline sketch of
fruiting organs, if found. See if any filaments can be found with
the contents massing or escaping at the tips. In some species

TYPES OF CRYPTOGAMS; THALLOPHYTES 247

zoospores are formed in this way, having their entire surface clothed
with cilia. They are the largest motile cells known. In other spe-
cies a portion of the filament is separated and cut off by a cell-wall.
Such spores soon germinate and may be found in various stages of
growth. They often serve for propagation through several genera-
tions before spores are- produced by fertilization.

With a power of about 200 diameters sketch a portion of a fila-
ment to show the form and location of chlorophyll. Sketch the
fruiting organs in detail, if any can be found.1

Antheridia and oogonia are formed near together on the same
filament. The antheridium is a cell forming the terminal portion
of a short branch, which is rather slender, straight or curved. Its
contents form numerous minute antherozoids, each with two cilia.
The cilia can be seen only with great difficulty, if at all, but their
presence is indicated by their active movements.

The oogonium is a short, somewhat spheroidal branch separated
by a cross-partition at the base. The cell-wall becomes ruptured at
the tip, allowing the entrance of the antherozoids by which it is
fertilized. After fertilization a cell-wall is formed about the oosphere,
and it matures as an oospore and enters upon a period of rest.

THE STUDY OF NITELLA

285. Occurrence. — Nitella is a green plant growing attached to
the bottom of ponds and streams, usually in shallow water. It is
not common everywhere but is widely distributed. Chara is similar
and may be used as a substitute but is more complicated.

286. General Aspect. — With the naked eye and a magnify-
ing glass note the general aspect of Nitella, the length of the stem-
like portions, from the root-like parts to the tip, the length of some
of the joints (internodes), the arrangement of leaf-like and branch-
like portions.

287. Protoplasm. — Examine the cells of sterns or leaves under a
low power. Select a vigorous cell of moderate size and examine

1 Goebel states that the formation of the fruiting organs begins in the even-
ing, is completed the next morning, and that fertilization takes place during
the day between ten and four o'clock.

248

FOUNDATIONS OF BOTANY

under a power of 200 or more diameters. Select the terminal cell
of the leaf if Cham is used. The protoplasm is nearly colorless but
usually contains bodies which can be seen moving in the current of
protoplasm. The protoplasm will show
normal activity at the temperature of a
comfortable living room. By focusing, see
if the current of protoplasm can be detected
moving in more than one direction.

Note the form and arrangement of the
chlorophyll and any places lacking chloro-
phyll, and see if you can tell whether the
arrangement has any relation to the current
of protoplasm. With a low power trace the
course in several cells. How many cells con-
stitute each internode of Nitella 1 If Chara
is used, iriternodes will be found to be
covered with a layer of many corticating
cells. Under a high power compare the
general structure of node and internode and
see if the attachment of leaves and branches
can be clearly determined. Compare the tip
of a leaf with the tip of a stem or branch
if the material permits. Are the fruiting
organs produced on the stems or the leaves?
288. Antheridia. — The antheridia are
globular bodies, bearing male fertilizing
cells and becoming red at maturity (Fig.
182). Eight cells compose the outer wall.
They have radial lines indicating folds and
join one another by irregular sutures. Xote
a round spot in the middle of each cell
which marks the point of attachment within
of the stalk on which antherozoid-producing cells are borne.

289. Oogonia. — The egg-shaped fruits, known as oogonia (Fig.
182), are borne near the antheridia in monoecious species. Count
the number of pointed cells which constitute the " crown " of the
fruit, Does each tip consist of one or two short cells ? Examine

FIG. 181. — End of a Main
Shoot of Chara. (About
natural size.)

TYPES OF CRYPTOGAMS; THALLOPIIYTES

249

the surface of the enveloping cells which enclose the spore. What
is their number and form ? What is their relation to the cells form-
ing the crown ? Focus so as to see the large egg-cell (oosphere or
oospore) which constitutes the center of the fruit. Can you determine
anything regarding its contents ?

Search for young oogonia and if practicable describe and draw
them in several stages of development. Their structure can be seen
much more easily than that of the
antheridia. Make drawings to illus-
trate various details of structure.

290. Characeae. — Nitella
and Char a are the genera
composing the group Chara-
cece, a group of green algee
differing widely from any
others. They show in a won-
derful manner simplicity of
cell-structure with a high
degree of organization. FIG. m- Part of a Leaf of rig. isi.

, j. , (Considerably magnified.)

Scarcely less wonderful are a)antheridium; 0,0ogonium. Atthe

the Care and precision with right are a young antheridium and

archegonium.

which botanists have worked

out their life history. As a study in evolution the Characece
may be considered as representing the highest develop-
ment attained along the line of filamentous green algse,
which, while preserving their algal characteristics, are
comparable in a remarkable degree with moss- and fern-
plants and with seed-plants. Every cell in the plant has
been accounted for and is understood in regard to origin,
relationship, and function. With harmony of structure
throughout, it has organs comparable to root, stem, and
leaf in seed-plants, each with characteristic structure and

250

FOUNDATIONS OF BOTANY

mode of growth. The stem has nodes and internodes.
The stem increases by the growth of an apical cell, but
growth in length depends chiefly on the elongation of each
internodal cell instead of the multiplication of numerous
internodal cells.

THE STUDY OF ROCKWEED1

291. Occurrence. — The common rockweed is abundant every-
where on rocks, between high and low tide, on the New England
coast and southward.

292. The Frond. — A plant of rockweed
consists mostly of a growth which is some-
what leaf-like, but, in fact, stem and leaf
are not separately developed, and the growth
is therefore called a thallus. This combined
stem and leaf has many flat leathery
branches which are buoyed up in the water
by air-bladders. Cut one of the bladders
open and note its form and appearance. Note
whether they occur singly or how grouped.
Note the prominent midrib running through-
out the middle of each branch. Examine
the swollen tips of some of the branches and
note their peculiarities. Sketch a portion
of a frond to show the characteristics so far
noted.

293. Reproduction. — Cut across through
the middle of one of the swollen fruiting
tips. Note the fruiting papillae (concep-
tacles) as they appear in this section, and
make a simple sketch to show their position.

Select some plants with brighter colored

FIG. 183.— Part of Thallus of tips and some less bright, if any difference
a Kockweed (Fucus platy-

carpus) , natural size. The
two uppermost branchlets
are fertile.

1 Fucus vesiculosus is the most available species.
Others may be substituted.

TYPES OF CRYPTOGAMS; THALLOPHYTES

251

FIG. 184. — Kockweed (Fucus).

zoids from same, x 330.

can be detected. After making the
microscopic examination which follows,
note what correspondence of structure
with color has been observed. Cut very
thin sections through fruiting tips from
different plants, keeping those from each
plant separate. Be sure that some of
the cuts pass through the conceptacle as
near the middle as possible.

Examine with a power of about sixty
diameters sections from different fronds,
searching for one kind containing rather
large egg-shaped cells and another con-
taining bundles of numerous smaller

sac-shaped cells. With a power of 200 ^, antheridia borne on branch-
diameters Study the details of the sec- ing hairs, X160; S, anthero-
tions. Note the character of the cells
forming the surface of the frond, those
of the inner structure, and those limit-
ing the cavity of the conceptacle. In a
conceptacle cut through the middle note
the form of the orifice. Examine the
slender hairs or filaments (paraphyses}
which, arising at right angles, line the
walls of the conceptacle.

294. Oogonia and Antheridia. — In
conceptacles containing egg-shaped cells
(oogonia) note the form,
mode of attachment (ses-
sile or stalked), and dif-
ferent stages of develop-
ment. At maturity the
contents are divided,
forming eight oospheres;
but not all can be seen FIG. 185. — Rockweed (^MCMS).

at once, some being ke_^>°ogonium, its contents dividing into eight oospheres,
x 160 ; B, an oosphere, escaped, surrounded by an-
neath the others. therozoids, x ieo.

252

FOUNDATIONS OF BOTANY

In conceptacles of the other kind examine the numerous small
sac-shaped cells' (antheridia). At maturity the contents of each
divide to form numerous very minute motile antherozoids, each with
two delicate hairs or cilia. Dissect, by picking and by friction under

cover-glass, a bunch of
antheridia and note
the branching fila-
ments upon which
they are borne.

Make drawings to
illustrate the various
points of structure.

295. Number of
Antherozoids required
for Fertilization. — The
bulk of an oosphere
has been estimated
equal to that of thirty
thousand to sixty
thousand antherozoids,
but apparently an
oosphere may be fer-
tilized by only one
antherozoid. Yet a
large number swarm
around each oosphere
after both have
escaped from the con-
ceptacles, and often
their movements are
so active as to cause the rotation of the oosphere. The process of
fertilization may be discerned in fresh material by squeezing
oospheres and antherozoids from their respective conceptacles into
a drop of water on a slide. In some species, as Fucus platycarpus
(Fig. 186), antheridia and oogonia are found in the same
conceptacle.

FlG. 186. — Transverse Section of Conceptacle of a
Rockweed (Fucus platycarpus). (x about 35 )

h, hairs ; a, antheridia ; o, oogonia.

TYPES OF CRYPTOGAMS; THALLOPHYTES 253

THE STUDY OF NEMALION

296. Occurrence. — Seven or eight species of Nemalion are known
in the world, but only one l is widely diffused, being found in Europe
and on the New England coast from Rhode Island northward. It
grows in salt water attached to exposed rocks at low-water mark.
Nemalion represents the largest of the groups of algse, nearly all of
which live in salt water and have the characteristic color ; but a few
live in fresh water.

297. Color. — Fresh specimens or those properly dried for the
herbarium show the color which is characteristic of the great group
to which Nemalion belongs. Dried specimens of " Irish moss "
(Chondrus) and many other species furnish good illustrations. There
are many variations of shade and intensity.

Place a piece of a fresh or dried specimen of some species in a
beaker of fresh water over night or longer and note the color of the
solution and of the treated specimen. Treat another piece similarly
with alcohol. A few genera related to Nemalion grow in fresh
water. What do you infer regarding their color ?

298. Form and General Character. — Examine specimens of
Nemalion and note the size, shape, mode of branching, nature, or
consistency of their substance. Examine a fragment of the plant
with a power of about sixty diameters and note how the structure
differs from what it appears to be to the naked eye. Do cells appear
more densely packed or differently colored at any points?

299. Structure. — From a small portion of the plant cut thin
longitudinal and transverse sections or pull it to pieces with needles
so as to expose the inner portion. Place on a slide under a cover-
glass in a drop of water. With a power of about 250 diameters or
more examine the general structure of the frond, as shown by a slide
prepared as above. Note the central portion (axis') of the frond as
dissected out, consisting of long, slender, thread-like cells. Examine
and draw the branching rows of cells which, radiating from the
axis, form the surrounding outer structure of the frond. Note the
tips of .these branches and look for the fruiting organs and fruit
(spores).

254

FOUNDATIONS OF BOTANY

FIG. 187. — Portions of Thallus of a Red Alga
(Chantransia). (Much magnified.)

A, filaments with antheridia, a ; B, young recep-
tive hair, or trichogyne, t ; C and D, successive
stages in the growth of the clustered fruit,/.

the spores at maturity. Are they naked
envelope ? Are they arranged in masses,

300. Organs for Repro-
duction. — The fruiting
organs are to be sought
on the radiating branching
filaments and are usually
produced in great abun-
dance during the summer.
Various stages of develop-
ment may be expected at
a given time. The anther-
ozoids are small spheres
without cilia, non-motile,
with a thin cell-wall. Look
for cells in which they are
formed (antkeridia), occur-
ring in groups at the tips
of the branches. Compare
these with the vegetative
cells.

301. Spore -Production.
— Look for spore-producing
organs in various stages.
In the young stage at the
time of fertilization, an-
therozoids, carried by cur-
rents of water, may be
found adhering. Note the
shape of the tip (trichogyne}
and the base (carpogonituri),
and find whether there is
any partition separating
them at this stage. Draw
or describe a few later
stages in development, and
note the arrangement of
or enclosed in any sort of
chains, or otherwise ?

TYPES OF CRYPTOGAMS; THALLOPHYTES

255

302. Other Florideae. — Nemalion represents one of the simplest
modes of fruiting in the red algae. In others there is great variety in
structure and great complication in the mode of fruiting. Some
species of Polysiphonia (or Dasya) may well be studied in compari-
son with Nemalion and in further illustration of this important
group.1 Understanding that a siphon, in algae, is a row of cells, end
to end, study the structure of a plant of Poly-
siphonia as illustrating its name. How many

siphons are there ? Do the main branches
have any other cells covering the surface (cor-
ticating cells) ?

Note the tufts of repeatedly forking, one-
siphoned filaments.

303. Fruiting of Polysiphonia. — The anther-
idia are to be sought on the branching fila-
ments just mentioned. Note how they differ
from those of Nemalion. The clustered fruits
or cystocarps will be recognized as ovoid- ©
globose or urn-shaped bodies attached
externally to the frond. Note whether €
the group of spores is naked or otherwise, @
whether the spores are produced singly

or in chains ; how attached ; shape.

Many Floridece have another kind of
fruiting bodies, spores produced without
fertilization, coordinate with the asexual
spores of black mould (see Sect. 308).
In Florideae, such spores are usually
found in fours and are called tetraspores.

Are tetraspores usually found on separate plants ?

In Polysiphonia the tetraspores appear to be formed in threes
(tripartite}, the fourth being underneath the three. When found,
describe their position and arrangement.

304. Algae. — Diatom, Oscillatoria, Pleurococcus, 8pi-
rogyra, Vaucheria, Nitella, Fucus, Nemalion, these eight

1 It is desirable also to exhibit fresh or pressed specimens of various genera
to show their general aspect.

FIG. 188.

A, spores of Nemalion (greatly
magnified); £, portion of
thallus of a red alga, Lejo-
Hsia, with tetraspores, t.

256 FOUNDATIONS OF BOTANY

plants which we have just studied, are types of several
families of plants which together make the great group
called AlgcjR. Something of its importance in nature is
indicated by these facts : The number of known species is
about 12,000. In size, the individuals in various species
range from a single cell of microscopic dimensions, as in
Pleurococcus, to the giant kelp of California which reaches
a length of more than 1000 feet. The form ranges from a
simple spherical cell as in Pleurococcus to an extensive,
branching cell in Vaucheria and its allies, specialized
organs in the form of root, stem, leaf, air-bladder, and
fruiting organs in Sargassum, which is an ally of Fucus.

The algae illustrate a series of modes of propagation
from simple division in Oscillatoria to the union of two
similar masses of protoplasm to form a spore in Spirogyra,
the direct fertilization of a germ-cell by motile anthero-
zoids in Vaucheria, Nitella, Fucus, the indirect fertilization
of fruiting cells by non-motile antherozoids in Nemalion.
In allies of the latter there are more intricate variations of
the same mode.

The algse fall into five natural groups based primarily
on the mode of fruiting. In most cases color is coordinate
with class arid may be relied upon as a superficial guide in
grouping ; but there are a few exceptions, e.g., some fruit-
ing like the red group are, nevertheless, green.

The nutrition of the brown and the red algae is similar
to that of the green algse, since the brown or red color
merely conceals the green of the chlorophyll which is
present in all and enables them all to take in and decom-
pose carbon dioxide.1

1 See Murray's Introduction to the Study of Seaweeds, pp. 4-6. London,
1895.

TYPES OF CRYPTOGAMS; THALLOPHYTES 257

305. Classification of Types studied.

DIATOMACE^E. Yellowish.

Diatoms.

CYANOPHYCE^E. Blue-green or some similar color.

Oscillatoria.
CHLOROPHYCE.E. Green.

Pleurococcus, Spirogyra,

Vaucheria, Nitella.
PH.EOPHYCE.E. Olive.

Fucus.
FLORIDE.E. Red.

Nemalion.

Polysiphonia.

THE STUDY OF BLACK MOULD (RHIZOPUS NIGRICANS)

306. Occurrence. — This mould maybe found in abundance on
decaying fruits, such as tomatoes, apples, peaches, grapes, and cher-
ries, or on decaying sweet potatoes or squashes. For class study it
may most conveniently be obtained by putting pieces of wet bread
on plates for a few days under bell-jars and leaving in a warm place
until patches of the mould begin to appear.

307. Examination with the Magnifying Glass Study some of

the larger and more mature patches and some of the smaller ones.
Note :

(a) The slender, thread-like network with which the surface of
the bread is covered. The threads are known as hyphce, the entire
network is called the mycelium.

(&) The delicate threads which rise at intervals from the myce-
lium and are terminated by small globular objects. These little
spheres are spore-cases. Compare some of the spore-cases with
each other and notice what change of color marks their coming to
maturity.

308. Examination with the Microscope. — Sketch a portion of the
untouched surface of the mould as seen (opaque) with a two-inch
objective, then compare with Fig. 189.

258

FOUNDATIONS OF BOTANY

Wet a bit of the mould, first with alcohol, then with water.
Examine in water with the half-inch objective, and sketch a little of
the mycelium, some of the spore-cases, and the thread-like stalks on
which they are borne. Are these stalks and the mycelium filaments
solid or tubular ? Are they one-celled or several-celled ?

Mount some of the mature spore-cases in water, examine them
with the highest obtainable power, and sketch the escaping spores.

FIG. 189. — Unicellular Mycelium of a Mould (Mucor Mucedo), sprung from a
Single Spore.

a, b, and c, branches for the production of spore-cases, showing various stages of
maturity, (Considerably magnified.)

Sow some of these spores on the surface of " hay-tea," made by
boiling a handful of hay in just water enough to cover it and then
straining through cloth or filtering through a paper filter. After
from three to six hours examine a drop from the surface of the
liquid with a medium power of the microscope (half-inch objective)
to see how the development of hyphae from the spores begins.
Sketch.

TYPES OF CRYPTOGAMS; THALLOPHYTES

259

After about twenty-four hours examine another portion of the
mould from the surface of the liquid and study the more fully
developed mycelium. Sketch.

309. Zygospores. — Besides
the spores just studied, zy go-
spores are formed by conju-
gation of the hyphse of the
black moulds. It is not very
easy to find these in process
of formation, but the student
may be able to gather from
Fig. 190 the nature of the
process by which they are
formed, — a process which can-
not fail to remind him of the
conjugation of pond-scum.

THE STUDY OF WHEAT

RUST (PUCCINIA

GKAMTNB)

310. Occurrence. —Wheat
rust is common on cultivated
wheat and other grains, and
also on many wild and culti-
vated forage grasses. In fact,
this or similar rusts occur on
a very large number of grasses,
and many species of such rusts
are recognked. A rust may
have one, two, or three kinds
of spores, and when three occur one is known as the cluster-cup stage
and the others as red rust and black rust, according to the usual
approximate color of the spores. The rust called Puccinia graminis
growing on wheat has its cluster-cup stage on the leaves of barberry
in June. The spores from the cluster-cups are carried by the wind
to the wheat, where they germinate and in a few days produce the

FIG. 190. — Formation of Zygospores in a

Mould (Mucor Mucedo).
1, threads in contact previous to conjuga-
tion ; 2, cutting off of the conjugating
cells, a, from the threads, b ; 3, a later
stage of the process ; 4, ripe zygospore ; 5,
germination of a zygospore and formation
of a spore-case. (1-4 magnified 225 diam-
eters, 5 magnified about 60 diameters.)

260

FOUNDATIONS OF BOTANY

red rust. A little later the black spores appear, produced from the
same mycelium. This growth is chiefly upon the stems and sheaths.

- 0

A B

FlG. 191. — Spore-Formation in Potato-Blight (Phytophthora infestans).

A, a well-developed group of stalks, proceeding from a mass of mycelium inside
the leaf and escaping through a stoma ; B, a young, unbranched stalk, h,
hyphse of mycelium ; o, stoma ; s, spore. (Both figures greatly magnified, B
more than A.) •

311. Cluster-Cup Stage. — Note with the naked eye and with a
magnifying glass the appearance of the cluster-cups upon the bar-
berry leaf. Fresh specimens should be used, if available. Note
whether the leaf is changed in form or color in any part occupied
by the fungus. Note the number of cups in a cluster, the position
on the leaf (which surface?), the form and size, especially the height.

TYPES OF CRYPTOGAMS; THALLOPHYTES 261

Are they straight or curved ? Describe the margin of the cup, the
color without, and the color of the contents.

With a power of 200 diameters or more examine some of the
cells composing the cup and note the form, color, and nature of the
surface. Draw. With the point of a needle or knife pick out a
bit of the contents of the cup and examine as above. Note the
characters as before and compare in detail with the cells of the cup.
The cells within the cup are the spores. Can you tell how they are
attached ?

A thin section through the cup will show the mode of attachment
and the relation of the spores to the cup.

312. Examination of Red and Black Rust. — Under the magnify-
ing glass examine the eruptions of spores (sort) on the wheat plant,
some of red spores and some of black spores. The red spores are
faded in dried specimens. . Note the approximate size and shape
and any other peculiarities. Prepare slides of each kind of spores
and see if both can be found in one sorus. The spores may be
taken from the host-plant on the point of a knife by picking rather
deeply down into the sorus. Place the small quantity of spores so

FIG. 192. — A Cluster-Cup of Anemone Rust (Puccinia fusca). (x 120.)
s, chains of spores ; p, the covering or peridium of the cup ; /*, hyphse.

obtained in a drop of water on a slide, spread with dissecting needles
and cover. Examine under a power of 200 or more diameters.

The red spores (uredospores) have each a stalk from which they
easily fall. They may be seen attached to their stalks if properly

262

FOUNDATIONS OF BOTANY

prepared cross-sections through the sorus are available, especially if
the material is fresh. Examine the spores and note the shape, color,
and surface. If the spores are shrunken, a drop of potash solution
will restore the natural plumpness. Draw. Spore-measurements are
important in determining species. The uredospores of Puccinia
graminis may be distinguished from those of other species common

on grasses by the greater proportionate
length.

The structure of the black spores
(teleutospores) can be made out with-
out difficulty. Some should be found
attached at the base. Note the parts
and the differences in color in different
portions. Make careful drawings to
show shape and structure of both kinds
of spores.

Boil a portion of a rust-injured plant
in potash solution, pick it to pieces 011
a slide under the magnifier or dissect-
ing microscope, use a cover-glass and
examine the preparation for mycelium,
using a high power.

313. Cultivation on a Host-Plant. —
If practicable, find some wheat or grass
which has remained over winter with
the black rust upon it. Tie a bunch
of this to a barberry bush while the
leaves are young or unexpanded. When
the time arrives for the appearance of
the cluster-cups, note whether they are any more abundant on this
bush than on others. Are you sure that the rust you have is the
one to which the barberry cluster-cups belong ?

FIG. 193. — A Group of Spores
of Wheat Bust (Puccinia
graminis). ( x about 440.)
ut 11, uredospores ; t, a teleu-
tospore.

TYPES OF CKYPTOGAMS; THALLOPHYTES 263

THE STUDY OF MICROSPH.ERA

314. Occurrence. — Species of Microsphcera and allied forms
occur in late summer and fall on leaves of various herbaceous and
woody plants. The growth is confined to the surfaces of the leaf
(upper, lower, or both). Among the most available species are
those which grow upon lilac, oak, grape, cherry, willow, and wild
plants of the sunflower family. Some species are known to occur
on only one host-plant, others occur on several or a large number,
and the host-plants may belong to one or more than one family.

Besides MicrospJicera there are about five other genera, any of
which may be substituted or studied comparatively. They are dis-
tinguished by the form of the appendages, together with the number
of spore-sacs (asci) in each sac-receptacle or perithecium.

The species of fungi which Microsphcera represents are called
powdery mildews.

With naked eye and magnifying glass examine the surface of a
leaf bearing powdery mildew. Note which surface and what portion
of the surface is occupied by the fungus, whether the occupied area
is restricted or not, the color, and any other characters.

315. Examination with the Microscope. — Place a small drop of
water on the leaf where the fungus occurs, if possible where dark-
colored specks occur among the mycelium. Pick from the leaf a
portion of the fungus loosened by the water and place with a drop
of water on a slide. Place a cover-glass over it. Examine under
a power of about fifty diameters. The dark-colored specks will be
seen as somewhat spherical bodies (perithecia). Note their structure
and color and their appendages. Have the perithecia any regular
way of opening? Note the length of the appendages as compared
with the diameter of the perithecia ; also note the form of the tips
and of the base, the color and any variation of color in different
parts of the appendages. Keep the left hand on the focusing screw,
and with the needle in the right hand press with gentle but varying
stress upon the cover-glass to rupture the perithecia. Even with
great care broken cover-glasses may result, but this pressure should
force out the contents of the perithecia. Another method is to
remove the slide from the microscope and, with a pencil rubber

264

FOUNDATIONS OF BOTANY

applied to the cover-glass, rupture the perithecia by gentle grinding
between the cover and slide. Note the number and form of the
spore-sacs (asci) expelled from each of several perithecia. Examine

under a power of about 200 diam-
eters and count the number of spores
in the asci. Gentle pressure may
make them more distinctly visible.
Make drawings to illustrate the
structural characters observed.

THE STUDY OF AGARICUS

316, Occurrence. — The common
mushroom, Agaricus campestris,
grows in open fields and pastures
in the United States and Europe.
It is the mushroom most extensively
cultivated for market, and if not
found in the field it may be raised
from " spawn " (mycelium), put up
in the shape of bricks, and sold by
seedsmen in the large cities. Those
who make a specialty of selling it
furnish directions for culture free.
A moderately warm cellar or base-
ment makes an excellent winter
garden for mushrooms.

317. Structure of Mycelium. —
Examine some of the spawn, or
mvcelium, with the magnifying glass
and the low power of the microscope,
and with a power of 200 diameters
or more examine the individual

hyphee which compose it. Are the hyphae united in cord-like strands
or otherwise, or are they entirely separate ? Look for cross-partitions
in the hyphae. Is there any peculiar structure to be found at these
places ? Are the cross-partitions near together or widely separated ?

FlG. 194. — A Mushroom (Agaricus

melleus).
my, mycelium ; c, c', c", young

"buttons" ; st, stipe or stalk ; r,

ring ; g, gills.

TYPES OF CRYPTOGAMS; THALLOPHYTES

265

hym

318, The Spore-Plant. — Search for indications of fruiting, and
note the appearance of the " button mushrooms " in all available
stages. Draw. See if at any stage up to maturity an outer envelope
of tissue (volva) can be found enclosing the entire fruiting body.
If such be present, what becomes of it at maturity? If material is
available, compare the species of Amanita (poisonous) in regard to this.

Examine specimens in which the cap is expanding and see if
there is another tissue forming a veil covering the under surface of
the cap. If such be pres-
ent, how is it attached
and what becomes of it ?

Take a fresh, well-
expanded mushroom or
toadstool. Remove the
stalk, or stipe, close under
the cap, or pileus, and lay
the latter, gills down, on
a piece of paper. Let it
remain undisturbed for a
few hours, or over night,
so that the spores may
fall upon the paper. Note
carefully their color, also
the form in which they
are arranged on the paper. What determines this form ? Examine
some of the spores under the highest available power of the micro-
scope. Measure and draw.

Describe the stipe. Is it a hollow tube or solid ? Does it taper ?
Note length, diameter, color.

Describe the cap, or pileus, in regard to diameter, thickness, nature
and color of the upper surface, also color below.

Examine the plates, or gills, which compose the under portion of
the pileus. Cut a complete pileus and stipe, through the center, and
draw an outline to show the shape, noting particularly how the gills
are attached. What is the color of the gills ?

319. Origin of Spores. — Make a cross-section of one of the gills,
and with a magnifying power of about 200 diameters examine the

B
FIG. 195. — Portions of Gills of

a Fungus (Agaricus).
A, slightly magnified ; B, one
of the parts of A, more mag-
nified, hym, hymenium ; />,
central layer.

266

FOUNDATIONS OF BOTANY

fruiting cells (basidia) which project at right angles to the gill and
bear the spores. At how many points (sterigmata) on each basidium
are spores attached ? Draw a basidium, preferably one from which
the spores have not yet fallen.

THE STUDY OF YEAST (SACCHAROMYCES CERE VISILE)

320. Growth of Yeast in Dilute Syrup. — Mix about an eighth of
a cake of compressed yeast with about a teaspoonful of water and
stir until a smooth, thin mixture is formed. Add this to about half

a pint of water in which a table-
spoonful of molasses has been
dissolved. Place this mixture in
a wide-mouthed bottle which holds
one or one and a half pints, stop-
per very loosely 1 and set aside for
from twelve to twenty-four hours
in a place in which the temper-
ature will be from 70 to 90 degrees.
Watch the liquid meantime and
note :

(a) The rise of bubbles of gas
in the liquid.

(6) The increasing muddiness
of the liquid, a considerable sedi-
ment usually collecting at the end
of the time mentioned.

(c) The effect of cooling off the
contents of the bottle by immers-
ing it in broken ice if convenient,
or, if this is not practicable, by
standing it for half an hour in a pail of the coldest water obtainable,
or leaving it for an hour in a refrigerator, afterwards warming the
liquid again.

(d) The effect of shutting out light from the contents of the
bottle by covering it with a tight box or large tin can.

1 If the cork is crowded into the neck with any considerable force, pressure
of gas and an explosion may result.

FIG. 196.— Part of the Preceding Figure,
(x about 300.)

(7, layer of cells immediately under the
hymenium ; s, s', s", three successive
stages in growth of spores.

TYPES OF CRYPTOGAMS; THALLOPHYTES 267

(e) The result of filling a test-tube or a very small bottle with
some of the syrup-and-yeast mixture, from which gas-bubbles are
freely rising, and immersing the small bottle up to the top of the
neck for fifteen minutes in boiling water. Allow this bottle to
stand in a warm place for some hours after the exposure to hot
water. What has happened to the yeast-plants?

(/) The behavior of a lighted match lowered into the air space
above the liquid in the large bottle, after the latter has been standing
undisturbed in a warm place for an hour or more.

(#) The smell of the liquid and its taste.

321. Microscopical Examination of the Sediment.1 — Using a very
slender glass tube as a pipette, take up a drop or two of the liquid
and the upper layer of the sediment and place on a glass slide, cover
with a very thin cover-glass and examine with the highest power
that the microscope affords.

Note:

(a) The general shape of the cells.

(&) Their granular contents.

Sketch some of the groups and compare the sketches with
Fig. 197.

Run in a little iodine solution under one edge of the cover-glass,
at the same time touching a bit of blotting paper to the opposite
edge, and notice the color of the stained cells. Do they contain starch ?

Place some vigorously growing yeast on a slide under a cover-
glass and run in a little eosiri solution or magenta solution. Note
the proportion of cells which stain at first and the time required for
others to stain. Repeat with yeast which has been placed in a slen-
der test-tube and held for two or three minutes in a cup of boiling
water.

With a very small cover-glass, not more than three-eighths of an
inch in diameter, it may be found possible by laying a few bits of
blotting paper or cardboard on the cover-glass and pressing it against
the slide to burst some of the stained cells and thus show their thin,
colorless cell-walls and their semi-fluid contents, protoplasm, nearly
colorless in its natural condition but now stained by the iodine.
1 See Huxley and Martin's Biology, under Torula.

268

FOUNDATIONS OF BOTANY

-b

EXPERIMENT XXXIX

Can Yeast grow in Pure Water or in Pure Syrup ? — Put a bit of
compressed yeast of about the size of a grain of wheat in about four
fluid ounces of distilled water, and another bit of about the same size
in four fluid ounces of 10 per cent solution of rock candy in distilled
water ; place both preparations in a warm place, allow to remain for
twenty-four hours, and examine for evidence of the growth of the
yeast added to each.

322. Size, Form, and Structure of the Yeast-Cell. — The student
has discovered by his own observations with the microscope that the
yeast-cell is a very minute object, — much smaller than most of the
vegetable cells which he has hitherto examined. The average diam-
eter of a yeast-cell is about ^-$^-3
of an inch, but they vary greatly
both ways from the average size.

The general form of most of
the cells of ordinary yeast is some-
what egg-shaped. The structure
is extremely simple, consisting of
a thin cell-wall, which is wholly
destitute of markings, and a more
or less granular semi-fluid proto-
plasm, sometimes containing a
portion of clearer liquid, the vacu-
ole, well shown in the larger cells
of Fig. 197.1

323. Substances which compose the Yeast-Cell. — The cell- wall is
composed mostly of cellulose; the protoplasm consists largely of
water, together with considerable portions of a proteid substance,2

1 This is not the ordinary commercial yeast.

2 It may be found troublesome to apply tests to the yeast-cell on the slide,
under the cover-glass. Testing a yeast cake is not of much value, unless it
may be assumed that compressed yeast contains little foreign matter and con-
sists mostly of yeast-cells. Still the test is worth making. Millon's reagent
does not work well, but the red or maroon color which constitutes a good test
for proteids is readily obtained by mixing a teaspoonful of granulated sugar
with enough strong sulphuric acid to barely moisten the sugar throughout,
and then, as quickly as possible, mixing a bit of yeast cake with the acid and

FIG. 197. — Yeast (Saccharomyces ellip-
soideus) budding actively.

A, a single cell ; B, group of two budding
cells ; C, a large group ; b, buds.

TYPES OF CRYPTOGAMS; THALLOPHYTES 269

some fat, and very minute portions of sulphur, phosphorus, potash,
magnesia, and lime. It is destitute of chlorophyll, as would be
inferred from its lack of green color, and contains no starch.

324. Food of the Yeast-Cell ; Fermentation. — The diluted molasses
in which the yeast was grown in Exp. XXXIX contained all the
mineral substances mentioned in Sect. 323, together with sugar,
proteid materials, and water. The addition of a little nitrate of
ammonium would probably have aided the growth of the yeast in
this experiment, by supplying more abundantly the elements out
of which the yeast constructs its proteid cell-contents. A great deal
of sugar disappears during the growth of the yeast.1 Most of the
sugar destroyed is changed into carbon dioxide (which the student
saw rising through the liquid in bubbles) and alcohol, which can
be separated from the liquid by simple means. The process
of breaking up weak syrup into carbon dioxide and alcohol by
aid of yeast is one kind of fermentation; it is of great practical
importance, in bread-making and in the manufacture of alcohol.
Since grape juice, sweet cider, molasses and water, and similar
liquids, when merely exposed to the air soon begin to ferment and
are then found to contain growing yeast, it is concluded that dried
yeast-cells, in the form of dust, must be everywhere present in
ordinary air.

325. Yeast a Plant; a Saprophyte. — The yeast-cell is known
to be a plant, and not an animal, from the fact of its producing
a coating of cellulose around its protoplasmic contents and from
the fact that it can produce proteids out of substances from which
animals could not produce them.2

On the other hand, yeast cannot live wholly on carbon dioxide,
nitrates, water, and other mineral substances, as ordinary green
plants can. It gives off no oxygen, but only carbonic acid gas, and
is therefore to be classed with the saprophytes, like the Indian pipe,
among flowering plants (Sect. 180).

sugar. A comparative experiment may be made at the same time with some
other familiar proteid substance, e.g., wheat-germ meal.

1 The sugar contained in molasses is partly cane sugar and partly grape
sugar. Only the latter is detected by the addition of Fehling's solution.
Both kinds are destroyed during the process of fermentation.

2 For example, tartrate of ammonia.

270 FOUNDATIONS OF BOTANY

326. Multiplication of Yeast. — It is worth while to notice the
fact that yeast is one of the few cryptogams which have for ages
been largely cultivated for economic purposes. Very recently yeast
producing has become a definite art, and the cakes of compressed
yeast so commonly sold afford only one instance of the success
that has been attained in this process. While yeast-cells are under
favorable conditions for growth, they multiply with very great
rapidity. Little protrusions are formed at some portion of the
cell-wall, as the thumb of a mitten might be formed by a gradual
outgrowth from the main portion. Soon a partition of cellulose
is constructed, which shuts off the newly formed outgrowth, making
it into a separate cell, and this in turn may give rise to others,
while meantime the original cell may have thrown out other off-
shoots. The whole process is called reproduction by budding. It is
often possible to trace at a glance the history of a group of cells,
the oldest and largest cell being somewhere near the middle of the
group and the youngest and smallest members being situated around
the outside. Less frequently the mode of reproduction is by means
of spores, new cells (usually four in number), formed inside one of
the older cells (ascws). At length the old cell-wall bursts, and the
spores are set free, to begin an independent existence of their own.

In examining the yeast-cell the student has been making the
acquaintance of plant life reduced almost to its lowest terms. The
very simplest plants consist, like the slime moulds, of a speck of
jelly-like protoplasm. Yeast is more complex, from the fact that its
protoplasm is surrounded by an envelope of cellulose, the cell-wall.

THE STUDY OF PHYSCIA

327. Occurrence. — Physeia is one of the commonest lichens. It
grows attached to the bark of various trees.

328. The Thallus. — Physeia consists chiefly of an irregularly
expanded growth somewhat leaf-like in texture. It is best to be wet
for study. Is it separable from the bark to which it is attached or
is it combined with it (incrusted) ? Describe the general outline of
the margin, the general color, and any special variations of color
above, also below. How is the thallus attached to the bark ?

TYPES OF CRYPTOGAMS; THALLOPHYTES

271

329. The Fruit. — Look for small lance-shaped disks seated upon
the thallus. Note the approximate sizes and color within and
without. These disks are called apothecia. Note the very minute
black specks (spermogones") which are scattered in the surface of
the thallus. Pick one from the thallus, with as little of the thallus
as possible, and examine under high power. It may be macerated
in a drop of potash solution and crushed under the cover-glass. If
the contents are not easily
defined, they may then be
made more opaque by a drop
of acetic acid or a stain. The
minute colorless bodies con-
tained in the spermogones are

Fro. 198. — A Lichen (Xanthoria).
(Natural size.)

FIG. 199. — A Lichen (Usnea).
(Natural size.)

called spermatia. Their office in Physcia is obscure, but in a few
lichens they are thought to unite with a trichogyne cell, as in the red
algse.1 Note the minute, powdery masses (soredid) on the surface
of the thallus. Macerate if necessary under the cover-glass and
examine under a high power. Compare with the structure of the
thallus as seen in cross-section. (See next paragraph.) These soredia
easily become detached and develop into new plants.

Prepare for sectioning by imbedding a small portion of the
thallus with an apothecium in a piece of pith or by any suitable
device for sectioning, and cut thin sections of thallus and fruit.

1 This, however, is doubtful. See Strasburger, Noll, Schenk, and
Schimper's Text-Book of Botany, p. 380.

272

FOUNDATIONS OF BOTANY

330. Examination of the Thallus. — The thallus of Physcia as seen
in cross-section will be found to consist of four layers, the upper
cortical, gonidial, medullary, and the lower cortical. The cortical
layers will be seen to serve for protection, answering the purpose of
an epidermis or bark. The cells which compose them make what
is called a false parenchyma, — resembling parenchyma in form but

as to origin being trans-

C ^r^ll/Mrr^fZ^^ }Y*tf\ ^S/ formed fungal hyphae.

Note the form of the
hyphae composing the
medullary layer. Are
there any cross-parti-
tions? Do any cells
appear circular, arid if
so, what is the explana-
tion? The upper por-
tion of the cortical
layer, having green
cells intermixed, con-
stitutes the gonidial
layer. Why should the
green cells be at the
upper part of the med-
ullary layer? Can you
detect any connection
between the green cells
and the hyphae ? Do
these green cells re-
semble any cells pre-
viously studied ?
Make a diagram to show the structure of the thallus.
What arrangement of layers would you expect to find in a lichen
thallus, upright or suspended ? Compare the arrangement in the
fruit-body (apotkecium), describe, and sketch. How does the layer
of cells beneath the spore-sacs resemble the cortical layer ? All but
these two layers may be considered as part of the thallus. To make
out the details of the fruit, the section must be very thin.

FIG. 200. — Transverse Section through Thallus
of a Lichen (Sticta fuliginosa) . (x 500.)

c, cortical or epidermal layer ; g, gonidia ; /t,hyphse.

TYPES OF CRYPTOGAMS; THALLOPHYTES 273

Examine the spore-sacs (asci) and look for spores in different stages
of formation. How many spores are found in each ascus ? What other
bodies occur among the asci? Draw these, also asci and spores.

331. Lichens. — Lichens were formerly supposed to be
a distinct class of plants, and it is only about thirty years
since their real nature began to be understood. A lichen
is now known to be a combination of two plants. The
green cells, called the gonidia, belong to some species of
alga, and the remainder, the larger portion of the growth,
is a fungus parasitic upon that alga. The groups of
lichens correspond in structure to certain groups of fungi,
but the genera are sufficiently distinct so that lichens are
best considered by themselves for purposes of study and
classification.

The relation of the fungus and its algal host is not
that of destructive parasitism, but rather a mutual rela-
tion (symbiosis) in which both fungus and alga may have
a vigorous growth. The relationship has been investi-
gated in various ways, and it has been found that, while
the alga may grow independent of the fungus, the germi-
nating fungus spores can grow only to a limited extent if
deprived of the algal host; but if supplied naturally or
artificially with the proper alga they make a normal
growth.

The same alga may serve as gonidia to a number of
lichens, often of very different form, and while the num-
ber of lichens reaches into the thousands, the number of
algse known to serve as gonidia is quite small.

Lichens are widely distributed in all zones but flourish
particularly in northern regions where other vegetation is
scanty. Some were formerly important as sources of

274 FOUNDATIONS OF BOTANY

dyes. "Iceland moss" is a lichen used for food, and a
finely branching form, growing in extensive mats on the
soil, serves as food for the reindeer and is known as
" reindeer moss."

Most lichens grow on the bark of trees, on rocks, or soil
where they have little moisture except during rainfall,
but some grow where they are constantly wet. Some of
the latter are gelatinous. Most of the conspicuous lichens
are foliaceous or else have a thallus composed of branch-
ing, cylindrical, thread-like portions. But many species,
often less conspicuous, are crustaceous, growing as if
they formed part of the bark or rock to which they are
attached.

332. Fungi. — The yeasts, moulds, rusts, mildews, and
mushrooms represent an immense group of plants of which
about forty-five thousand species are now known in the
world. They range from the very simple to quite com-
plex forms, growing as saprophytes or parasites under a
great variety of conditions. Their structure and life
history are so varied as to constitute a long series of divi-
sions and subdivisions.1 Chlorophyll is absent from fungi,
and they are destitute of starch, but produce a kind of
cellulose which appears to differ chemically from that of
other plants. Unable to build up their tissues from car-
bonic acid gas, water, and other mineral matters, they are
to be classed, with animals, as consumers rather than as
producers, acting on the whole to diminish rather than to
increase the total amount of organic material on the earth.

1 See Strasburger, Noll, Schenk, and Schimper's Text-Book of Botany,
pp. 340-381 incl., also Potter and Warming's Systematic Botany, p. 1, and
Engler's Syllabus der Pflanzenfamilien, Berlin, 1898, pp. 25-47.

TYPES OF CRYPTOGAMS; THALLOPHYTES 275

333. Occurrence and Mode of Life of Fungi. — Among
the most important cryptogamous plants are those which,
like the bacteria of consumption, of diphtheria, of typhoid
fever, or of cholera, produce disease in man or in the
lower animals. The subclass which includes these plants
is known by the name Bacteria. Bacteria are now classed
by some as a separate group, lower than fungi. Some of
the most notable characteristics of these plants are their
extreme minuteness and their extraordinary power of
multiplication. Many bacteria are on the whole highly
useful to man, as is the case with those which produce
decay in the tissues of dead plants or animals, since these
substances would, if it were not for the destructive action
of the bacteria of putrefaction and fermentation, remain
indefinitely after death to cumber the earth and lock up
proteid and other food needed by new organisms.

The mushrooms and their allies include about one-fourth
of the fungi. Some, such as the " dry-rot " fungus, mis-
takenly so called, cause great destruction to living and
dead tree trunks and timber in economic use. The com-
mon mushroom, Agaricus campestris, is the most important
edible species. Probably five hundred kinds can be eaten,
but only a few are good food, and even these contain but little
nutriment. Some species are dangerous, and a few are deadly
poisons. The puffballs are a small group allied to the mush-
rooms. Most of them are edible and of good quality.

The mildews (Microsphcera, etc.) and the "black-knot"
of the plum trees are of a group which likewise includes
about one-fourth of the fungi. A considerable number
are parasites, injurious to vegetation, while thousands of
others grow on dead leaves, twigs, etc.

276 FOUNDATIONS OF BOTANY

The "rust" of wheat and the "smut" of corn repre-
sent groups numbering only a few hundreds of species,
which are very important because they are all parasites
on living plants, many on our most important economic
plants.

Fig. 191, representing another small group of destruc-
tive parasites, shows clearly how a parasitic fungus grows
from a spore which has found lodgment in the tissues of
a leaf and pushes out stalks through the stomata to dis-
tribute its spores.

CHAPTER XXI
TYPES OF CRYPTOGAMS; BRYOPHYTES

334, The Group Bryophytes. — Under this head are
classed the liverworts and the mosses. Both of these
classes consist of plants a good deal more highly organized
than the thallophytes.
Bryophytes have no
true roots, but they
have organs which
perform the work of
roots. Some of them
have leaves (Fig. 206),
while others have
none (Fig. 201).
Fibro - vascular bun-
dles are wanting. The
physiological division
of labor is carried
pretty far among all
the bryophytes. They
have special appara-
tus for absorbing
water and sometimes
for conducting it
through the stem; stomata are often present and some-
times highly developed. There are chlorophyll bodies,
often arranged in cells extremely well situated for acting

277

FIG. 201. —Part of Male Thallus of a Liverwort

(Marchantia disjuncta). (Enlarged.)

mr, male receptacle.

278

FOUNDATIONS OF BOTANY

on the carbon dioxide gas which the plant absorbs, that is,
arranged about rather large air chambers.

Reproduction is of two kinds, sexual and asexual, and
the organs by which it is carried on are complicated and
highly organized. An alternation of generations occurs,
that is, the life history of any species embraces two forms :
a sexual generation, which produces two kinds of cells that

by their union give
rise to a new plant ;
the asexual genera-
tion, which multiplies
freely by means of
special cells known
as spores.

FIG. 202. —Part of Female Thallus of
M. disjuncta. (Enlarged.)

fr, female receptacle ; c, cups with gemmae.

THE STUDY OF
MARCHANTIA

335. Occurrence.—

Marchantia grows on soil
or rocks in damp shaded places and is widely distributed.

336. The Thallus. — In general form the thallus bears some resem-
blance to that of some of the lichens, as Parmelia, but is plainly
different in color, mode of branching, and internal structure under
the microscope. Under the microscope (see below) the individual
cells may be compared with those of the medullary layer in PJiyscia.

Note the color and general shape of the thallus and study care-
fully the mode of branching. The origin of the growing cells is at
the tip, but cells so originating afterward multiply more rapidly, so
that the tip comes to be in a notch.

Viewing the thallus as an opaque object, note the diamond-shaped
network on the upper surface and the dot-like circle in the middle
of each diamond.

Examine the under surface for (1) rhizoids and (2) scales.

TYPES OF CRYPTOGAMS; BRYOPHYTES

279

idial Receptacle of Marchantla.
(Magnified.)

a, antheridium.

337. Internal Structure. — Cut thin cross-sections of the thallus
in the same way as for Physcia, making some pass through the cir-
cular dots mentioned above. Exam-
ine under a high power and note the
different kinds and layers of cells
composing the thallus. Note the
character of the cells forming the
upper and lower surfaces. Describe
the cells which are next above those
of the lower epidermis, their shape,
color of contents, approximate num-
ber of horizontal rows. Have they
any evident intercellular spaces ? Find

FIG. 203. — Section through Anther- cells connecting these with the upper

epidermis and constituting the net-
work of lines seen on the surface of
the thallus. Note the air cavity

bounded by these lines and the loose cells which occupy it in part.

What is the color of their contents ? How are they attached, and

how arranged? Can you discover any

opening through the epidermis? If so,

describe it.

Make drawings to illustrate the details

of structure observed.

338. Gemmae. — Look for a thallus
bearing little green cups formed of its
own substance. Describe the contents
of the cup. The bodies are called gemmce.
They originate by vegetative growth alone
and when detached may grow into new
plants.

339. Fruiting Organs. — Look for thalli
bearing stalks with umbrella-like expan-
sions. The umbrellas are of two kinds,
one disk-like with crenate points (how

many ?) and the other has rays (how many ?) elongated and curving
downward. Is there any difference in the height of the two kinds ?

FIG. 204. — Sectional View of
an Antheridium of Mar-
chantia.

a, antheridium ; az, anthero-
zoids, x 700.

280

FOUNDATIONS OF BOTANY

Do both occur on the same thallus ? On what part of the thallus
do they occur, and do they differ in this respect ?

340, Antheridia. — The antheridia are formed as outgrowths
from the upper surface of the crenate receptacle, but by further
growth of the receptacle they become imbedded. They should be
examined under a high power and sketched in outline. The anther-
idium produces numerous motile antherozoids, each with two cilia.

341, Archegonia and Sporophytes. — The receptacle with recurved
rays bears the archegonia. Note whether they occur above or below
and in what relation to the rays. How are the archegonia protected ?

Note the cells which surround
the central canal and form the
elongated neck of the archego-
nium. Does the archegonium
open upward or downward ? At
the base look for the germ-cell.

The antherozoids enter the
central canal and penetrating
to the egg-cell fertilize it, after
which it begins to divide and
grows into a sporophyte. In the
older specimens, therefore, the
sporophytes will be found more
or less developed. The archegonium remains upon the tip of the
sporophytes. The mature sporophyte contains the spores and also
peculiar elongated tapering threads with spiral thickenings. These
are called elaters.

342, Hepaticae. — Marchantia represents only a small
division of the Hepaticce, and is not typical of the larger
number of species. In spite of this it is chosen for study,
because it is widely distributed and more available for
study than most others. In most species the fruit lasts
but a little while and good material is hard to obtain. In
Marchantia the fruiting organs are abundant, more gradual
in their development, and more persistent. Marchantia and

FIG. 205. — Sectional View of Female
Receptacle of Marchantia. (x 5.)

TYPES OF CRYPTOGAMS ; BRYOPHYTES 281

its allies consist chiefly of the thallus in the vegetative con-
dition, while the greater number of Hepaticee have a stem
and leaves. Thus they approach closely to the mosses.
But mosses usually have leaves on all sides of the stem,
while the leaves of Hepaticse are two-ranked, spreading
laterally, with sometimes a third row of leaves or scales
underneath. The leaves of mosses usually have more than
one layer of cells in some part, but the leaves of the leafy
Hepaticse have but one layer of cells throughout. The
forms of the leaves are often very curious and interesting.
The sporophyte of most mosses consists of a capsule with
a lid, while in the leafy Hepaticse the capsule usually
opens by splitting longitudinally into two to four valves.

Different species of Hepaticee grow on damp soil, rocks,
and the bark of trees. Many are capable of enduring
drought and reviving with moisture.

THE STUDY OF PIGEON-WHEAT MOSS
(P&LYTRICHUM COMMUNE}

343. Occurrence. — This moss is widely distributed over the sur-
face of the earth, and some of its relatives are among the best
known mosses of the northern United States. Here it grows
commonly in dry pastures or on hillsides, not usually in densely
shaded situations.

344. Form, Size, and General Characters. — Study several speci-
mens which have been pulled up with root-hairs. Note the size,
general form, color, and texture of all the parts of the plants exam-
ined. Some of them probably bear spore-capsules or sporopkytes like
those shown in Fig. 206, while others are without them. Sketch one
plant of each kind, about natural size.

JVTiat difference is noticeable between the appearance of the
leaves in those plants which have spore-capsules and those which
have none ? Why is this ?

282

FOUNDATIONS OF BOTANY

In some specimens the stem may be found, at a height of an inch
or more above the roots, to bear a conical, basket-shaped enlargement,

FIG. 206. —A Moss, Catharinea.

The sporophytes of this moss are usually rather more slender than as
here represented.

TYPES OF CRYPTOGAMS; BRYOPHYTES

283

out of the center of which a younger portion of the stem seems to
proceed ; and this younger portion may in turn end in a similar
enlargement, from which a still younger part proceeds.

Note the difference in general appearance between the leaves of
those plants which have just been removed from the moist collecting-
box and those which have been lying for half an hour on the table.
Study the leaves in both cases with the magnifying glass in order to
find out what has happened to them. Of what use to the plant is
this change ? Put some of the partially dried leaves in water, in a

prim

FIG. 207. — Protonema of a Moss.

prim, primary shoot ; h, a young root-hair ; pi, young moss-plant ;
br, branches of primary shoot.

cell on a microscope slide, cover, place under the lowest power of
the microscope, and examine at intervals of ten or fifteen minutes.
Finally sketch a single leaf.

345. Minute Structure of the Leaf and Stem. — The cellular
structure of the pigeon-wheat moss is not nearly as simple and con-
venient for microscopical study as is that of the smaller mosses, many
of which have leaves composed, over a large part of their surfaces,
of but a single layer of cells, as shown in Fig. 209. If any detailed
study of the structure of a moss is to be made, it will, therefore, be
better for the student to provide himself with specimens of almost

284

FOUNDATIONS OF BOTANY

any of the smaller genera,1 and
work out what he can in regard
to their minute anatomy.

FIG. 208. — The Antheridium
of a Moss (Funaria) and its
Contents.

a, antheridium ; 6, escaping
antherozoids, x 350 ; c, a sin-
gle antherozoid of another
moss, x 800.

e *s

I J

FIG. 209. — Portions of Fertile Plant
of a Moss (Funaria).

A, longitudinal section of summit of
plant, x 100 ; a, archegonia ; I,
leaves ; E, an archegonium, x 550 ;
e, enlarged ventral portion with
central cell ; n, neck ; TO, mouth.

346. Sporophytes. — That part of the reproductive apparatus of
a common moss which is most apparent at a glance is the sporophyte
or spore-capsule (Fig. 206). This is covered, until it reaches maturity,
with a hood which is easily detached. Remove the hood from one

1 As Mniwn or Bryum.

TYPES OF CRYPTOGAMS; BRYOPHYTES 285

of the capsules, examine with a magnifying glass, and sketch it.
Note the character of the material of which its outer layer is
composed.

Sketch the uncovered capsule as seen through the magnifying
glass, noting the little knob at its base and the circular lid.

Pry off this lid, remove some of the mass of spores from the
interior of the capsule, observe their color as seen in bulk through
the magnifying glass, then mount in water, examine with the high-
est obtainable power of the microscope, and sketch them. These
spores, if sown on moist earth, will each develop into a slender,
branched organism, consisting, like pond-scum, of single rows of
cells (Fig. 207) called the protonema.

347. Other Reproductive Apparatus. — The student cannot, with-
out spending a good deal of time and making himself expert in the
examination of mosses, trace out for himself the whole story of the
reproduction of any moss. It is sufficient here to give an outline of
the process. The protonema develops buds, one of which is shown
in Fig. 207, and the bud grows into an ordinary moss plant. This
plant, in the case of the pigeon-wheat moss, bears organs of a some-
what flower-like nature, which contain either antheridia (Fig. 208),
organs which produce fertilizing cells called antherozoids, or arcTie-
gonia (Fig. 209), organs which produce egg-cells, but in this moss
antheridia and archegonia are not produced in the same "moss-
flower." The plants therefore correspond to dioecious ones among
flowering plants.

After the fertilization of the egg-cell, by the penetration of
antherozoids to the bottom of the flask-shaped archegonium, the
development of the egg-cell into sporophyte begins ; the latter rises
as a slender stalk, while the upper part of the archegonium is
carried with it and persists for a time as the hood or calyptra.

CHAPTER XXII
TYPES OF CRYPTOGAMS; PTERIDOPHYTES

348. The Group Pteridophytes. — Under this head are
classed the ferns, the scouring-rushes, and the club-mosses.
They are the most highly organized of cryptogams, having
true roots, and often well-developed stems and leaves.

THE STUDY OF A FERN*

349. Conditions of Growth. — If the specimens studied were col-
lected by the class, the collectors should report exactly in regard to
the soil and exposure in which the plants were found growing. Do
any ferns occur in surroundings decidedly different from these?
What kind of treatment do ferns need in house culture?

350. The Underground Portion. — Dig up the entire underground
portion of a plant of ladyfern. Note the color, size, shape, and
appendages of the rootstock. If any are at hand which were col-
lected in their late winter or early spring condition, examine into
the way in which the leafy parts of the coming season originate
from the rootstock, and note their peculiar shape (Fig. 210, A).
This kind of vernation (Sect. 136) is decidedly characteristic of ferns.
Observe the number and distribution of the roots along the rootstock.
Bring out all these points in a sketch.

1 The outline here given applies exactly only to Asplenium filix-fcemina.
Any species of Asplenium or of Aspidium is just as well adapted for study.
Cystopteris is excellent, but the indusium is hard to find. Polypodium vut-
gare is a simple and generally accessible form, but has no indusiuin. Pteris
aquilina is of world-wide distribution, but differs in habit from most of our
ferns. The teacher who wishes to go into detail in regard to the gross anat-
omy or the histology of ferns as exemplified in Pteris will find a careful study
of it in Huxley and Martin's Biology, or a fully illustrated account in Sedg-
wick and Wilson's Biology.

286

TYPES OF CRYPTOGAMS; PTERIDOPHYTES 287

351. The Frond. — Fern leaves are technically known as fronds.
Observe how these arise directly from the rootstock.

Make a somewhat reduced drawing of the entire frond, which
consists of a slender axis, the rhachis, along which are distributed
many leaflets or pinnce, each composed of many pinnules. Draw the
under side of one of the pinnae, from near the middle of the frond,
enlarged to two or three times its natural size, as seen through the
magnifying glass. Note just how each pinnule is attached to its
secondary rhachis.

Examine the under side of one of the pinnules (viewed as an
opaque object without cover-glass) with the lowest power of the
microscope, and note :

(a) The " fruit-dots " or sori (Fig. 210, B) (already seen with the
magnifying glass, but now much more clearly shown).

(&) The membranous covering or indusium of each sorus (Fig.
210, C). Observe how this is attached to the veins of the pinnule.
In such ferns as the common brake (Pteris} and the maidenhair
(Adianturri) there is no separate indusium, but the sporangia are
covered by the incurved edges of the fronds.

(c) The coiled spore-cases or sporangia, lying partly covered by
the indusium. How do these sporangia discharge their spores ?

Make a drawing, or several drawings, to bring out all these points.

Examine some of the sporangia, dry, with a power of about fifty
or seventy-five diameters, and sketch. Scrape off a few sporangia,
thus disengaging some spores, mount the latter in water, examine
with a power of about 200 diameters, and draw.

352. Life History of the Fern. — When a fern-spore is sown on
damp earth it gradually develops into a minute, flattish object,
called a prothallium (Fig. 211). It is a rather tedious process to
grow prothallia from spores, and the easiest way to get them for
study is to look for them on the earth or on the damp outer surface
of the flower-pots in which ferns are growing in a greenhouse. All
stages of germination may readily be found in such localities.

Any prothallia thus obtained for study may be freed from par-
ticles of earth by being washed, while held in very small forceps, in
a gentle stream of water from a wash-bottle. The student should
then mount the prothallium, bottom up, in water in a shallow cell,

288

FOUNDATIONS OF BOTANY

FIG. 210. — Spore-Plant of a Fern (Aspidium Filix-mas).

A, part of rootstock and fronds, not quite one-sixth natural size ; fr, young fronds
unrolling ; J3, under side of a pinnule, showing sori, s ; C, section through a
sorus at right angles to surface of leaf, showing indusium, i, and sporangia, s ;
.D, a sporangium discharging spores. (B is not far from natural size. C and
D are considerably magnified.)

TYPES OF CRYPTOGAMS; PTERIDOPHYTES

289

cover with a large cover-glass, and examine with the lowest power
of the microscope. Note :

(a) The abundant root-hairs, springing from the lov»T3r surface
of the prothallium.

(&) The variable thickness of the prothallium, near the edge,
consisting of only one layer of cells.

The student can hardly make out for himself, without much
expenditure of time, the structure of the antheridia and the arclie-
gonia (Fig. 211, ,4),
by the cooperation
of which fertilization
takes place on much
the same plan as that
already described in
the case of mosses.
The fertilized egg-
cell of the archego-
nium gives rise to
the young fern, the
sporophyte which
grows at first at the
expense of the parent
prothallium but soon
develops roots of its
own and leads an in-
dependent existence.

353. Nutrition.—
The mature fern
makes its living, as flowering plants do, by absorption of nutritive
matter from the soil and from the air, and its abundant chlorophyll
makes it easy for the plant to decompose the supplies of carbon
dioxide which it takes in through its stomata.

FIG. 211. — Two Prothallia of a Fern (Aspidium).
A, under surface of a young prothallium ; ar, arche-
gonia ; an, antheridia ; r, rhizoids ; B, an older pro-
thallium with a young fern-plant growing from it ;
I, leaf of young fern. (Both x about 8.)

290 FOUNDATIONS OF BOTANY

FERNS

354. Structure, Form, and Habits of Ferns. — The struc-
ture of ferns is much more complex than that of any of
the groups of cryptogamous plants discussed in the earlier
portions of the present chapter. They are possessed of
well-defined nbro-vascular bundles, they form a variety of
parenchymatous cells, the leaves have a distinct epidermis
and are provided with stomata.

Great differences in size, form, and habit of growth are
found among the various genera of ferns. The tree ferns
of South America and of many of the islands of the Pacific
Ocean sometimes rise to a height of forty feet, while the
most minute species of temperate and colder climates are not
as large as the largest mosses. Some species climb freely,
but most kinds are non-climbing plants of moderate size,
with well-developed rootstocks, which are often, as in the
case of the bracken-fern, or brake,1 and in Osmunda, very
large in proportion to the parts of the plant visible above
ground.

355. Economic Value of Ferns. — Ferns of living species
have little economic value, but are of great interest, even
to non-botanical people, from the beauty of their foliage.

During that vast portion of early time known to geolo-
gists as the Carboniferous Age, the earth's surface in many
parts must have been clothed with a growth of ferns more
dense than is now anywhere found. These ferns, with
other flowerless herbs and tree-like plants, produced the
vegetable matter out of which all the principal coal beds
of the earth have been formed.

1 Pteris aquilina.

TYPES OF CRYPTOGAMS; PTERIDOPHYTES 291

356. Reproduction in Ferns. — The reproduction of ferns
is a more interesting illustration of alternation of gen-
erations than is afforded by mosses. The sexual plant,
gametophyte, is the minute prothallium, and the non-
sexual plant, sporophyte, which we commonly call the
fern, is merely an outgrowth from the fertilized egg-cell,
and physiologically no more important than the sporophyte
of a moss, except that it supplies its own food instead of
living parasitically. Like this sporophyte, the fern is an
organism for the production of vegetative spores, from
which new plants endowed with reproductive apparatus
may grow.

THE STUDY OF A CLUB-MOSS (LYCOPODIUM}

357. Occurrence. — Several species of Lycopodium are common in
rich woods in the northern and mountainous portions of the eastern
United States. Any species may be studied.

358. Examination. — Note whether the plant is chiefly erect or
prostrate and vine-like. Describe the mode of branching. Are the
leaves arranged flat-wise or equally on all sides of the stem ? Describe
the leaves briefly. Are they all of one kind or do some portions of
the plant evidently have smaller leaves?

Select fruiting specimens and determine the position of the spo-
rangia. Is the leaf, near whose base each sporangium is situated, like
the ordinary foliage leaves of the plant ? Are the fruiting portions
of the plant similar in general aspect or different from the rest of
the plant and raised above it on stalks ? Examine the spores. Are
they all of one kind ?

If Selaginella is used in place of Lycopodium or for comparison,
two kinds of sporangia are to be sought, differing chiefly in shape.
Describe each briefly. Compare the number of spores in each. The
larger spores (macrospores) germinate and at length produce pro-
thallia bearing archegonia, while the smaller produce prothallia
bearing antheridia. The archegonia, after fertilization, develop each

292

FOUNDATIONS OF BOTANY

an embryo. This grows, remaining for a time attached to the
macrospore, and at length forms a new spore-plant.

THE STUDY OF A SCOUBING-RUSH (EQUISETUM}

359, Occurrence. — The common horse-tail, Equisetum arvense, is
widely distributed in the United States, east, west, north, and south.
It is very often found on sand hills and along railroad embankments.

FIG. 212. — Plant of Lycopodium (L. annotinum).

The fruiting stems appear very early in the spring and are of short
duration. The sterile vegetative growth follows, becoming well
grown in June.

360. Examination of Rootstocks and Roots. — Examine the under-
ground portions of the plant with reference to general size, position,
color, shape, and position of notches. After studying the stems

TYPES OF CRYPTOGAMS; PTEKIDOPHYTES 29$

above ground insert here any evident points of comparison. Do you
find any special forms of stem development suited to a special pur-
pose ? Are there any organs in the nature of leaves ?

FIG. 213.— A Scouring-Kush (Equisetum sylvaticum) . At the right is a
colorless fertile stem, in the middle a green sterile one, and at the
left a green fertile one.

294 FOUNDATIONS OF BOTANY

361. Sterile Stems. — Examine the stems above ground with
reference to their color and mode and degree of branching. What
is the character of the leaves ? Do the stems in any sense serve as
leaves? Observe the nodes composing the stem and note the posi-
tion of the leaves on the stems. Do they appear to be placed several
at the same level (whorled) ?

Examine with a magnifying glass the surface of the stem and
note the number of ridges and grooves. Compare the number and
position of the leaves with reference to these.

362. Mineral Matter in Stem. — Treat small pieces of the stem
with strong nitric acid to remove all vegetable substance and note
the mineral substance remaining. Treat in a similar way thin cross-
sections and examine under the microscope. The substance is
silica. It gives the plant its gritty feeling and its name and use as
" scouring-rush." Of what use is it to the plant? Use of the same
substance in outer rind of corn stem, bamboo stem, and straw of
grains ?

363. Microscopic Examination. — Make thin cross-sections of the
stem and examine under the lowest power of the microscope. Make
a diagrammatic sketch to indicate the central cavity, the number
and position of the nbro-vascular bundles, the cavity or canal in
each, the ring of tissue surrounding the ring of bundles, and the
larger cavities or canals outside of this. Where is the chlorophyll
located? Can stomata be found, and if so, what is their location
and arrangement?

364. Fertile Stems. — Describe the fruiting stem with reference to
general aspect, size, color, number, and length of internodes, position
of spore-bearing portion, color of spores in mass. Note the shield-
shaped bodies (transformed leaves or sporophylls} composing the
cone-like "flower" and see whether any joints can be detected where
they are attached. Examine the inner surface of the shields for
sporangia and spores. Examine the sporangia under a low power
of the microscope. Examine some spores under a higher power.
Note the two bands, elaters, on each spore, crossing each other and
attached only at the point of crossing, forming four loose appendages.
Watch these while some one moistens them by gently breathing
upon them as they lie uncovered on the slide under the microscope

TYPES OF CRYPTOGAMS; PTERIDOPHYTES

295

and note the effect. Also note the effect of drying. How does this
affect the spores ? Use of the bands ?

365. Germination of Spores. — The spores germinate while fresh
and form prothallia corresponding to those of ferns, but generally
dioecious. The prothallium which bears the antheridia remains
comparatively small, and the antheridia are somewhat sunken. The
others grow much larger and branch profusely.

The terminal portion becomes erect and ruffled.
Near this part the archegonia are formed, quite
similar to those of ferns. The embryo plant
developing from the germ-cell has its first leaves
in a whorl. This at length grows into a spore-
plant like that shown in Fig. 213.

About twenty-five species of Equisetum are
known. Several may be looked for in any
locality and may well be compared with the one
described above, in regard to form, mode of
branching, and mode of fruiting.

366, Fern-Plants (Pteridophytes). -

The Pteridophytes (literally fern-plants)
include in their general category not only
ferns as commonly recognized, but several
other small groups which are very inter-
esting on account of their diversity. All
cryptogams higher than mosses belong in
this group. In moss plants the individ-
uals growing from spores and bearing
antheridia and archegonia, the gameto-
phytes, are full-grown leafy plants, and
the spore-bearing plant, or sporophyte, is
merely a stalk bearing a sporangium. In
all the fern-plants the reverse is true.
The individuals growing from spores and

, . , . ,. , . a, mouth of a ferti-

bearing antheridia and archegonia are of iized arcnegomum.

FIG. 214. — Part of a
Lobe of the Mature
Female Prothal-
lium of Equisetum.
(x about 50.)

296 FOUNDATIONS OF BOTANY

minor vegetative development (prothalUa), while the spore-
bearing plant is a leafy plant, even a tree in some ferns.

The ferns in the strictest sense have sporangia derived
from the epidermis (transformed hairs), while a few plants
closely resembling them in general aspect (Botrychium, etc.)
have sporangia formed in the tissue of the leaf.

In the next subdivision, the water-ferns (Fig. 215), there
is little resemblance to the common ferns. The sporangia
are in special receptacles at the basal portion of the plant.
The spores are of two kinds, dioecious, one on germination,
producing antheridia, the other archegonia. This group
includes two rooting forms, Marsilea (with leaves resem-
bling a four-leaved clover) and Pilularia, bearing simple
linear leaves, and two floating forms, Salvinia (Fig. 215)
and Azolla.

The remaining groups of fern-plants are the horse-tails
and the club-mosses. The horse-tails have only one kind
of spore and are peculiar chiefly in their vegetative aspect
(Fig. 213), while the spore-bearing leaves, or sporophylls,
are arranged in the form of a cone, as already shown.

The club-mosses include some plants which, as their
name implies, have a superficial resemblance to a large
moss, with the addition of a club-shaped stalked fruiting
spike. These are the so-called "ground pines" and the
running ground " evergreens " used for Christmas festoons
in New England. Technically the group is distinguished
by the possession of firm-walled sporangia formed singly
near the bases of the leaves. The ordinary club-mosses
already referred to have but one kind of spore, while
plants called Selaginella and Isoetes have two kinds of
spores, in this respect resembling Marsilea. In many

TYPES OF CRYPTOGAMS; PTERIDOPHYTES 297

species of Selaginella the leaves are arranged flat-wise on
the stem, so that considered physiologically the branch-
ing stem and its leaves together serve as a foliage leaf.
In one of the commonest American forms, however, the
stem is more nearly erect, and the leaves are all alike and
four-ranked.

Isoetes (quill-wort) grows attached to the soil in shallow
water at the bottoms of ponds. It has the aspect of short
grass growing in bunches. The large sporangia are at the
broad bases of the leaves.

367. High Organization of Pteridophytes. — The student
may have noticed that in the scouring-rush and the club-
moss studied there are groups of leaves greatly modified
for the purpose of bearing the sporangia. These groups
are more nearly equivalent to flowers than anything found
in the lower spore-plants, and the fern-plants which show
such structures deserve to be ranked just below seed-plants
in any natural system of classification.

The variety of tissues which occur in pteridophy tes is
frequently nearly as great as is found in ordinary seed-
plants, and the fibro-vascular system is even better devel-
oped in many ferns than in some seed-plants.

Starch-making is carried on by aid of abundant chloro-
phyll bodies contained in parenchyma-cells to which car-
bonic acid gas is admitted by stomata. In many cases
large amounts of reserve food are stored in extensive root-
stocks, so that the spring growth of leaves and stems is
extremely rapid.

CHAPTER XXIII
THE EVOLUTIONARY HISTORY OF PLANTS

368. The Earliest Plant Life. —What sort of plants first
appeared on the earth has never been positively ascertained.
The oldest known rocks contain carbon (in the form of
black lead or graphite) which may represent the remnants
of plants charred at so high a temperature and under so
great pressure as to destroy all traces of plant structure.
Some objects supposed by many to be the remains of large
alffse have been found in rocks that date back to a very

o «/

early period in the life history of the earth, before there
were any backboned animals, unless possibly some fishes.
Judging from the way in which the various groups of
plants have made their appearance from the time when
we can begin clearly to trace their introduction upon the
earth, it is probable that some of the simplest and lowest
forms of thallophytes were the first to appear. Decaying
animal or vegetable matter must have been less abundant
than is now the case, so that a plant that could make
part Or all of its food from raw materials would have had
a better chance than a saprophyte that could not. Water-
plants are usually simpler than land-plants, so it is highly
probable that some kind of one-celled aquatic alga was
the first plant.

369. Fossil Plants. — Fossils are the remains or traces
of animals or plants preserved in the earth by natural
processes. Fossil plants, or parts of plants, are very

298

THE EVOLUTIONARY HISTORY OF PLANTS 299

common ; the impressions of fern-leaves in bituminous coal
and pieces of wood turned into a flint-like substance are
two of the best known examples.

The only way in which we can get knowledge about
the animals and plants that inhabited the earth's surface
before men did is by studying such rocks as contain the
remains of living things. In this way a great deal of
information has been gained about early forms of animal
life and a less amount about early plant life, — less because
as a general thing plants have no parts that would be
as likely to be preserved in the rocks as are the bones
and teeth of the higher animals and the shells of many
lower ones.

370. The Law of Biogenesis. — An extremely important
principle established by the study of the development of
animals and plants from the egg or the seed, respectively,
to maturity is this : The development of every individual is
a brief repetition of the development of its tribe. The prin-
ciple just stated is known as the law of biogenesis. As
eggs develop during the process of incubation, the young
animals within for a considerable time remain much alike,
and it is only at a comparatively late stage that the wing
of the bird shows any decided difference from the fore-leg
of the alligator or the turtle. Zoologists in general are
agreed that this likeness in the early stages of the life
history of such different -animals proves beyond reasonable
doubt that they all have a common origin, that is, are
descended from the same kind of ancestral animal.

Among plants the liverworts and ferns supply an excel-
lent illustration of the same principle. In both of the groups
the fertilized egg-cells, as the student may have learned

300 FOUNDATIONS OF BOTANY

by his own observations, are much alike. As the egg-cell
grows and develops, the sporophyte of a liverwort, which
proceeds from the egg-cell, is extraordinarily unlike the
" fern" or asexual generation (gametophyte) among Filices.
Now this progressive unlike ness between liverworts and
ferns, as they develop from the fertilized egg-cell, points to
the conclusion that both groups of plants have a common
origin or that the more highly organized ferns are direct
descendants of the less highly organized liverworts.

371. Plants form an Ascending Series. — All modern
systems of classification group plants in such a way as to
show a succession of steps, often irregular and broken,
seldom leading straight upward, from very simple forms
to highly complex ones. The humblest thallophytes are
merely single cells, usually of microscopic size. Class
after class shows an increase in complexity of structure
and of function until the most perfectly organized plants
are met with among the dicotyledonous angiosperms.
During the latter half of the present century it first
became evident to botanists that among plants deep-seated
resemblances imply actual relationship, the plants which
resemble each other most are most closely akin by descent,
and (if it were not for the fact that countless forms of plant
life have wholly disappeared) the whole vegetable kingdom
might have the relationships of its members worked out by a
sufficiently careful study of the life histories of individual
plants and the likeness and differences of the several groups
which make up the system of classification.1

1 See Campbell's Evolution of Plants and Warming's Systematic Botany,
Preface and throughout the work. In the little flora of the present book, the
families are arranged in the order which, according to the best recent German
authorities, most nearly represents their relationships.

THE EVOLUTIONARY HISTORY OF PLANTS 301

372. Development of the Plant from the Spore in Green
Algae, Liverworts, and Mosses. — The course which the
forms of plant life have followed in their successive ap-
pearance on the earth may be traced by the application
of the law above named. Such algse as the pond-scums
produce spores which give rise directly to plants like the
parent.

In many liverworts the spore by its germination produces
a thallus which at length bears antheridia and archegonia.
The fertilized archegonium develops into a sporophyte
which remains. attached to the thallus, although it is really
a new organism. Liverworts, then, show an alternation of
generations, one a sexual thallus, the gametophyte, the
next a much smaller, non-sexual sporophyte, and so on.

A moss-spore in germination produces a thread-like pro-
tonema which appears very similar to green algae of the
pond-scum sort. This at length develops into a plant with
stem and leaves, the sexual generation of the moss. The
fertilized archegonium matures into a sporophyte which is
the alternate, non-sexual generation. This is attached to
the moss-plant, or gametophyte, but is an important new
organism. In the moss, as in the liverwort, the sexual
generation is the larger and the more complex ; the non-
sexual generation being smaller and wholly dependent for
its food supply on the other generation, to which it is
attached.

373. Development of the Plant from the Spore in Pterido-
phytes. — In the pteridophytes there is an alternation of
generations, but here the proportions are reversed, the
prothallium, or sexual generation, or gametophyte, being
short-lived and small (sometimes microscopic), and the

302

FOUNDATIONS OF BOTANY

non-sexual generation, the sporophyte, often being of large

size. The ferns (non-sexual generation), for instance, are
perennial plants, some of them tree-
like.

Some pteridophytes, as the Salvinia,
a small floating aquatic plant, some-
times known as a water-fern (Fig.
215), produce two kinds of spores,
the large ones known as macrospores,
and the small ones known as micro-
spores (Fig. 216). Both kinds pro-
duce microscopic prothallia, those of
the former bearing only archegonia,
those of the latter only antheridia.
From the prothallia of the macro-
spores a plant (non-sexual generation)
of considerable complexity of struc-
ture is formed.
374. Parts of the Flower which correspond to Spores. —

In seed-plants the spore-formation of cryptogams is repre-
sented, though in a way not

at all evident without careful

explanation. The pistil is the

macrospore-producing leaf or mac-

rosporophyll, and the stamen is

the microspore-producing leaf or

microsporopTiyll. Pines and other

gymnosperms produce a large cell

(the embryo sac) in the ovule

(Fig. 217), which corresponds to the macrospore, and a

pollen grain which represents the microspore. In its

FIG. 215. — A Water-Fern
(Salvinia).

FIG. 21 6.— Twolndusiaof Salvinia.

mi, microspores ; ma, macro-
spores.

THE EVOLUTIONARY HISTORY OF PLANTS

303

development the macrospore produces an endosperm which
is really a small cellular prothallium, concealed in the ovule.
The microspore contains vestiges of a minute prothallium.

In the angiosperms the macrospore and its prothallium
are still less developed, and the
microspore, or pollen grain, has
lost all traces of a prothallium
and is merely an antheridium
which contains two generative
cells.1 These are most easily
seen in the pollen grain, but
sometimes they are plainly visi-
ble in the pollen tube (Fig. 164).
Phanerogams are distinguished
from all other plants by their
power of producing seeds, or
enclosed macrosporangia, with
embryos.

375, The Law of Biogenesis
and the Relationships of the Great
Groups of Plants. — On summing
up Sects. 372-374 it is evident
that the sexual generation in
general occupies a less and less
important share in the life of the
plant as one goes higher in the scale of plant life.2 In the
case of the rockweed, for instance, the sexual generation
is the plant. Among mosses and liverworts the sexual

1 Sometimes only one generative cell escapes from the pollen grain into the
pollen tube, and there it divides into two cells.

2 A good many plants of low organization, however, are not known to pass
through any sexual stage.

FIG. 217. — Longitudinal Section
through Fertilized Ovule of a
Spruce.

p, pollen grains ; t, pollen tubes ;
n, neck of the archegonium ;
a, body of archegonium with
nucleus ; e, embryo sac filled
with endosperm.

304 FOUNDATIONS OF BOTANY

generation is still very prominent in the life of the plant.
Ordinary ferns show us the sexual generation existing only
as a tiny independent organism, living on food materials
which it derives from the earth and air. In the Salvinia
it is reduced to microscopic size and is wholly dependent
on the parent-plant for support. Among seed-plants the
sexual generation is so short-lived, so microscopic, and so
largely enclosed by the tissues of the flower that it is com-
paratively hard to demonstrate that it exists.

The fact that the life history of so many of the classes
of plants embraces a sexual stage, in which an egg-cell is
fertilized by some sort of specialized cell produced wholly
for use in fertilization, tends strongly to show the com-
mon origin of the plants of all such classes. We have
reason to believe, from the evidence afforded by fossils,
that plants which have only a sexual generation are
among the oldest on the earth. It is therefore likely that
those which spend the least portion of their entire life in
the sexual condition were among the latest of plants to
appear. Then, too, those which have the least developed
sexual generation are among the latest of plants. Judged
by these tests the angiosperms must be the most recently
developed of all plants.

If one were to attempt to arrange all the classes of
existing plants in a sort of branching series to show the
way in which the higher plants have actually descended
from the lower, he would probably put some one of the
green algae at the bottom and the angiosperms at the top
of the series.

376. The Oldest Angiosperms. — It is impossible to give
any of the reasons for the statements of this section

THE EVOLUTIONARY HISTORY OF PLANTS 305

without making an unduly long chapter. Briefly, it may
be stated that the monocotyledons are the simplest and
probably the oldest angiosperms ; the dicotyledons are
higher in organization and came later. The descent and
various relationships of the families of dicotyledons can
be discovered by the study of the flower, fruit, and seed
better than by the examination of the vegetative organs.

The entire pedigree of the several families cannot be
represented by arranging the names of the families in a
straight line. It is, however, in a general way, as indi-
cated by the succession of families in the Flora which
accompanies this book, the Willow Family being perhaps
the oldest (of the more familiar ones) and the Composite
Family the youngest.

PART II

ECOLOGY

CHAPTER XXIV
PLANT SOCIETIES

377. Ecology. — Plant ecology includes all that portion
of botany which has to do with the way in which plants get
on with their animal and plant neighbors, and especially
the way in which they adjust themselves to the nature
of the soil and climate in which they live. Ecology, in
short, discusses the relations of plants to their surround-
ings or environment. A good deal of what has been said
in previous chapters about such topics as parasitic plants,
the occurrence of winter bud-scales, the movements of
leaves, the coating of hairs on stems and leaves, the
storage of water in epidermis-cells, is really ecological
botany, although it is not so designated in the sections
where it occurs.

378. Plant Societies. — In a single acre of woodland,
of marsh, or of meadow, there will usually be found a
large number of species of plants. One species may be
sufficiently abundant and conspicuous to give a name to
the whole tract, so that it may, for instance, be recognized
as a bit of birch wood or of cat-tail swamp. But under
the birches and among the cat-tails there are plants, it may

307

308 FOUNDATIONS OF BOTANY

be, of a hundred other kinds — the seed-plants — not all in
bloom at any one season, but coming along in succession
from earliest spring until the approach of winter. The
entire set of plants which naturally occupies a given area
of land under somewhat uniform conditions is called a
plant society.

379. Similar Societies due to Similar Conditions. — As
soon as the young botanist begins to collect plants in a set
of localities new to him, he discovers that his old acquaint-
ances are still to be found grouped as he has been accus-
tomed to see them. The rich black loam of a wooded
bank a hundred miles away from his familiar collecting
ground will show the same assemblage of slippery elms
and lindens, red buds, bladdernuts, and wahoos, hepaticas,
bloodroots, Dutchman's breeches, trilliums, pepper root, and
wild ginger, with a multitude of later-blooming herba-
ceous plants, that he has learned to know so well. The
muddy borders of ponds from Maine to Minnesota and
beyond are fringed with the same kinds of bur-reeds and
sedges, set with water-plantain, and decorated with the
soft white blossoms of the arrowhead. The sand dunes
along the northern Atlantic coast and those that border
Lake Michigan are clothed with a sparse vegetation which
in both cases includes the little beach plum, such coarse
grasses as that shown in Plate I, and the straggling sea
rocket. Barnyards and waste grounds about farm build-
ings from Massachusetts to Missouri contain such weeds
as the dog fennel, the low mallow (" cheeses"), mother-
wort, catnip, and some smartweeds.

A little study of such cases soon leads one to the con-
clusion that these plant societies and multitudes of others

PLANT SOCIETIES 309

exist because all the plants in each society are adapted to
their special environment. Wherever such an environment
occurs such a society will be found in it,1 or, if not already
there, will nourish when introduced.

380. Similar Species replace Each Other Two sets of

localities alike in many respects but unlike in some points
are often inhabited by different species of the same genus.
For instance, the pine barrens of New England and the
adjacent states are commonly covered with the northern
pitch pine, while far southward, in sandy soil, its place
is taken by the long-leaved pine. Along streams and
swamps northward the speckled alder is generally found,
while southward the smooth alder is most common. In
rich woods of the northeastern United States the painted
trillium and the erect trillium ("Benjamin," or " squaw
root ") are the commonest species, while far south, in simi-
lar localities, the sessile trillium, Underwood's trillium,
and the large-flowered trillium are abundant.

In all such cases — and they are very numerous — we
are to infer that the genus is peculiarly well adapted to
some especial set of conditions, as sandy soil, brooksides, or
the rich, shaded soil of woodlands. But the more northerly
species are capable of enduring the severe winters and
brief summers of their region, while the more southerly
ones perhaps cannot do so. The relative warmth of the
climates in which they live may not be the only reason, or
even the principal reason, for the distribution of such
plants as those just mentioned, but it is one factor at any
rate. And it is certain that, on the whole, most of our

1 That is, in localities not separated by such natural barriers as seas, high
mountains, or deserts.

810 FOUNDATIONS OF BOTANY

native and thoroughly naturalized plants are growing
under what is, for them, the best environment, since they
cannot usually be made to exchange places with each
other. If a square mile of land in Louisiana were to be
planted with Minnesota species, and a square mile in
Minnesota with Louisiana species, it is very improbable
that either tract, if left to itself, would long retain its
artificial flora. To this rule there are, however, important
exceptions (see Sect. 457).

381. Plant Formations. — It is not uncommon to find
tracts of land or water inhabited by great numbers of
plants of the same species so as almost to exclude all
other plants except microscopic cryptogams. Ponds and
slowly flowing streams are often filled in this way with
the water hyacinth or the American lotus. The cane-
brakes of the south and the wild rice swamps along north-
ern lakes and rivers are other examples of an extremely
simple flora spread over large areas. Prairies not infre-
quently for hundreds of square miles are covered mainly
(not entirely) with a very few kinds of grasses. Such
assemblages are called plant formations or plant colonies.

382, Ecological Classification of Plants. — The ordinary
classification of plants, as set forth in Chapter XIX, is
based, as far as possible, on their actual relationships . to
each other. But when plants are classified ecologically
they are grouped according to their relations to the world
about them. They may, therefore, be gathered into as
many (or more than as many) different groups as there
are important factors influencing their modes of life. We
may classify plants as light-loving and darkness-loving,
as requiring free oxygen, and not requiring it, and so on.

PLANT SOCIETIES 311

Indeed, one of the most useful classifications of bacteria,
for practical purposes, is into species which must have free
oxygen, that is, oxygen not chemically combined with other
substances, in order to grow and increase, and those which
can live without it.

The most important consideration in classifying seed- .
plants on ecological grounds is based on their require- /
ments in regard to water. Grouped with reference to '
this factor in their life all plants may be classed as :

(1) Hydrophytes, or water-loving plants.

(2) Xerophytes, or drought-loving (or perhaps drought-tolerating)

plants.

(3) Mesophytes, or plants which thrive best with a moderate supply

of water.

These three classes do not fully express all the relations
of plants to the water supply, so two others are found
convenient.

(4) Tropophytes, or seasonal plants which are hydrophytes during

part of the year and xerophytes during another part.1

(5) Halophytes, or salt marsh plants and " alkali " plants, species

which can flourish in a very saline soil.

383. Difficulties in Ecological Classification. — It seems
at first sight a simple matter to group plants in regard to
their need of water. There can be no difficulty in classi-
fying as hydrophytes all plants like the bladderworts, water
cresses, certain mosses, and many lower spore-plants which
live only in water. Cactuses, aloes, and similar plants are
recognized at sight as xerophytes. But the chief difficulty

1 The plants which E. Warming, one of the foremost authorities, classes as
mesophytes are many of them grouped by another great authority, A. F. W.
Schimper, as tropophytes.

312

FOUNDATIONS OF BOTANY

is in dividing mesophytes from the other two classes, into
which they shade by indefinite gradations. In order to
know whether the plants of a region have plenty of water
or not, we must know not only how many inches of yearly
rainfall there are, but also what the soil is like, what is
the temperature of the soil and air, whether or not there
are dry winds, and whether there are
fogs or heavy dews. A lichen on a
bare rock may be living almost under

FIG. 218. —Aquatic Plants : Pond-Lilies with Floating Leaves and
Sedges with Aerial Leaves.

desert conditions, while a pitcher-plant in a bog near by
has its roots in standing water (or in ice) nearly all the
year round.

384. Hydrophytes. — Some of these are herbaceous
aquatic plants, like the duckweed, the pickerel-weed,
the pond-lily, and the water-crowfoot ; others, such as the
"calla" (Richardia), the buckbean, the cat-tail, and the
sweet flag, many ferns, mosses, and liverworts, prefer

PLANT SOCIETIES

313

damp air and soil. All of tliem transpire freely, and many
of them cannot live at all under the moisture conditions
which suit ordinary plants.

Some aquatics have their leaves wholly submerged,
others, such as the duckweed and the pond-lilies (Fig. 218),
have them floating, and still others, like the sedges in the
same picture, have their leaves freely exposed to the air.
A few plants have both
water-leaves and air-leaves
(Fig. 219). Soine aquatic
plants are rooted in the mud,
while others have no roots
at all, or, like the duckweed,
have only water-roots.

The leaves of land-plants
in very rainy, subtropical
climates are exposed to the
attacks of parasitic spore-
plants which flourish on
their surfaces. To ward off
the attacks of these it is
necessary to keep water from accumulating on the surfaces
of the leaves. This result is secured by a waxy deposit on
the epidermis and also by the slender prolongation to drain
off surplus water, shown in Fig. 221. That this slender
leaf tip is useful in the way suggested is proved by the fact
that when it is cut squarely off the leaf no longer sheds
water freely.

385. Xerophytes. — A xerophyte is a plant which is
capable of sustaining life with a very scanty supply of
water. Since the first plants which existed were aquatics

FIG. 219. — Submerged and Aerial Leaves
of a European Crowfoot (Ranunculus
Purshii). The leaf with thread-like
divisions is the submerged one.

314

FOUNDATIONS OF BOTANY

FIG. 220. — The Duckweed, a Floating
Aquatic Plant.

(Sect. 368), we must

^JSP^^ZTIZV consider that xero

¥S_~dSi^ pyhtes are highly spe-

cialized and modified
forms adapted to ex-
tremely trying condi-
tions of life. A typical
xerophyte is one which
can live in a very dry
soil in a nearly rain-
less region. The yucca
in Plate VII and the
melon-cactus (Fig. 49)

are good examples of such plants.

Less extremely xerophytic are plants

like the date-palm (Fig. 54), which

flourishes in the oases of the Sahara,

where the soil is moist from the

presence of springs, though rains are

almost unknown, or the houseleeks

and stonecrops found in many gar-
dens, the so-called Spanish moss

(Plate IV), and lichens (Figs. 198,

199), all of which grow most rapidly

in moist air, but cling to bare rocks

and trunks of trees, from which they

get no water. A xerophyte must

be capable of storing water and tran-

spiring very slowly, like cactuses,

aloes, Stonecrops, and SUCh fleshy plants with a Slender Taper-

ing Point to drain off
1 Ficus religiosa. Water.

PLANT SOCIP:TIES

315

FlG. 222. — A Field of Prickly-Pear Cactus Plants : Xerophytes.

316

FOUNDATIONS OF BOTANY

with a thick epidermis^ or else it must be able to revive
after being thoroughly dried. A few seed-plants and
many such spore-plants as lichens, Pleurococcus (Sect.
277), yeast, and some bacteria (Sect. 263), thrive just as
well after remaining for some months
or years in a dried condition as they
did before drying. A good illustration
of this fact as regards yeast is found in
the use of dried yeast cakes, made of a
mixture of yeast and corn meal. These
will raise dough promptly when mixed
with it, even if they have been kept
dry for a year or more.

386. Roots and Stems of Xerophytic
Seed-Plants. — Some xerophytes have
roots which show no peculiarities of
form or structure, but many make special
provision for storing food and water in
their roots. Such roots are fleshy and
often, as in Harpagophytum (Fig. 223),
are of great size compared with the
portion of the plant above the ground.
Xerophytic stems are frequently very
thick in proportion to their length,
sometimes even globular, and they
commonly contain large amounts of water. In leafless
plants, like the cacti, the surface for transpiration is much
less than that offered by leafy plants. Many species which
bear leaves shed most of them at the beginning of the dry
season, and some remain thus in a half dormant condi-
tion for long periods, as is the case with many Euphorbias

FIG. 223. — Harpago-
phytum, a South
African Xerophyte.

PLATE VII. — Tree Yucca in the Mohave Desert

PLANT SOCIETIES 317

(Fig. 245). The epidermis, even on the younger portions
of the stem, is highly cutinized (Fig. 121), and this structure
makes any evaporation very slow.

387. Leaves of Xerophytes. — In regions where the
greatest dangers to vegetation arise from long droughts
and the excessive heat of the sun, the leaves of plants
usually offer much less surface to the sun and air than is
the case in temper-

ate climates. Some-
times the blade of
the leaf is absent
and the expanded
petiole answers the
purpose of a blade,

Or, again, foliage FIG. 224. — Cross-Section of Rolled-Up Leaf of Crow-
leaveS are altO- Berry (Empetrum nigruin). (Magnified.)

gether lacking, as in the cactuses (Fig. 222), and the green
outer layers of the stem do the work of the leaves.

388. Rolled-Up Leaves. — Leaves which receive but a
scanty supply of water are often protected from losing it
too rapidly by being rolled up, so that the evaporating,
i.e., stomata-containing, surface is on the inside of the roll.
Sometimes, as in the crow-berry (Fig. 224), the curled con-
dition is permanent. In other plants, as in such grasses
as Stipa (Fig. 225), and in Indian corn, the leaf rolls up
when the weather is very dry and unrolls again when it
receives a better supply of water.

389. Mesophytes. — A mesophyte is a plant which
thrives best with a moderate supply of water. The great
majority of the wild and the cultivated plants of the
United States are mesophytes, and what has been learned

318 FOUNDATIONS OF BOTANY

from Part I of this book about the forms, structure, and
habits of ordinary plants, together with what the student's
own observation, aside from the study of botany, has taught
him, should suffice to give him a fair idea of mesophytic
plant life.

The typical mesophyte of the northern United States is
an annual, since most of our larger perennials pass the
winter in a xerophytic condition, to avoid destruction by
drying up during the long period when
the roots can absorb little or no water

FIG. 225. — Cross-Section of Leaves of a Grass,1 unrolled for Exposure to
Sunlight and rolled up to prevent Evaporation.

r, ridges of the upper epidermis, with many stomata on their surfaces ;
e, thick lower epidermis, without stomata.

from the frozen soil. Our evergreen coniferous trees,
such as pines, spruces, cedars, and so on, have leaves of
decidedly xerophytic structure. So also do such ever-
green shrubs as the rhododendrons, wintergreen, arbutus,
holly, and bearberry. Our deciduous trees and shrubs and
most perennial herbs are tropophytes (Sect. 390).

390. Tropophytes, or Seasonal Plants. — Examples of
these are most deciduous trees and the majority of the
perennials of temperate regions, for instance oaks, elms,
birches among trees, and tulips, crown imperials, lilies,
hyacinths, spring-beauties, peonies, dahlias, and potatoes
among herbs. Such plants have a pretty large surface for

1 Stipa capillata.

PLANT SOCIETIES

319

transpiration during the summer (or in regions like South-
ern California in the rainy season) and a greatly reduced
surface during the winter (or the dry season).

In the case of trees the reduction of surface is brought
about by the fall of the leaves (Sect. 186), and in the case
of herbaceous perennials it is secured* by the death of the
green stem and the leaves, so that only a compact root,
rootstock, or bulb is left alive underground. That is to
say, the perishable or annual part of tropophytes has the
characteristics of mesophytes or even of moisture-loving
plants, while the perennial part is constructed on the plan
of xerophytes.

391. Halophytes. — A halophyte is a plant which can
thrive in a soil containing much common salt or other
saline substances. The seaside obviously occurs to one as
the region of halo-
phytic vegetation,
but many inland
areas contain halo-
phytic plants, for
instance the neigh-
borhoods about salt
springs and the
" alkali " lands of
the southwest and
the Pacific Slope.
The presence of salt
in the soil renders
absorption of the
soil-water comparatively difficult, since osmosis takes place
more readily between ordinary water and the liquid

FIG. 226. — The Mangrove, a Halophytic Tree of
Southern Florida and the Tropics.

320 FOUNDATIONS OF BOTANY

contents of root-hairs and young roots than between salt
water and the liquids inside the root. Halophytes, there-
fore, are put on short rations as regards water, even
though they may be growing in a watery marsh. Con-
sequently halophytes often have much the appearance of
fleshy xerophytes and the structure of xerophytes.

The mangrove tree (Fig. 226) is one of the most remark-
able of halophytes. It grows in shallow water along the
seashore and sends out many aerial roots which at length
find their way down into the salt mud. In this way it
collects drift material and gradually extends the shore line
farther out to sea.

392. Other Kinds of Ecological Classes. — It is easy to
class plants according to their habits in many other regards
than according to their relative power of transpiration (see
Chapter XXVI). Only one other kind of classification
need, however, be mentioned in this chapter, that is, the
division into sun-loving and shade-loving plants. Even in
very dense forests some plants will be found growing on
the soil in the twilight formed by the shade of the trees.
Some of this undergrowth is of seed-plants, and there are
many ferns and mosses which flourish in such situations.
Shade-plants commonly have large pale leaves, and gener-
ally (except in ferns) the leaves are not much cut or
lobed (Fig. 227, 1). Sun-loving plants, on the other hand,
usually have comparatively little leaf-surface, and the
leaves are often cut into narrow divisions (Fig. 227, II).
Apparently the broad leaf-surfaces in the one class are to
expose many green cells to the light for starch-making,
while in the other class the slender leaf-divisions expose
enough assimilating cells, and at the same time the

PLANT SOCIETIES

321

narrowness of the division permits plenty of light to
penetrate to the plant's lower leaves. It is also, doubt-
less, much easier for leaves like those of the yarrow, the
dog fennel, the tansy, the carrot, and their like, to with-
stand the action of
severe winds, to
which they are often
exposed, than it
would be for leaves
like those of the jack-
in-the-pulpit (see
Frontispiece), the
trilliums, the lily-of-
the- valley, and simi-
lar leaves.

393, Transition of
a Plant from Shade
Conditions to Sun
Conditions. — It is
characteristic of
many kinds of forest
trees that the young
seedlings are much
more tolerant of
dense shade than the
adult trees are.
Sometimes their seeds will hardly germinate at all unless
thoroughly shaded, and the young trees for the first few
years flourish best in the shade. Afterwards most trees
need a good deal of sunlight, but they may live long
with a scanty supply of light. The red spruce sometimes

i ii

Fi<i. 227. — I, a Shade-Plant (Clintonia) ; II, a Sun-
Plant, Dog Fennel (Maruta).

322

FOUNDATIONS OF BOTANY

FIG. 228. — An Epiphytic Fern (Platycerium) on a Tree Trunk.

The more upright leaves next the trunk of the tree serve to collect water
and to accumulate a deposit of decaying vegetable matter, while the
outer leaves serve as foliage and bear spores.

PLANT SOCIETIES 323

lingers on for fifty or a hundred years, reaching meantime
a diameter of not more than two inches, and then, on
getting more light, shoots up into a large and valuable
timber tree.1

394. Epiphytes. — It is even easier for a plant to secure
enough sunlight in a forest region by perching itself upon
the trunk or branches of a tree than by climbing, as our
wild grapevines and the great tropical lianas do. There
is a large number of such perched plants, or epiphytes,
embracing species of many different groups of seed-plants
and of spore-plants. The fern shown in Fig. 228 is a good
example of an epiphyte. Instances among seed-plants are
the so-called Florida moss (Plate IV) and orchids like
those in Fig. 13.

1 See the Primer of Forestry, Part I, U. S. Department of Agriculture,
1899, pp. 33-35.

CHAPTER XXV
BOTANICAL GEOGRAPHY

395. Regions of Vegetation. — The earth's surface (that
of the land) has been described by one of the greatest of
geographical botanists 1 as divided into twenty-four regions
of vegetation. This classification takes account of all the
principal continental areas which have a characteristic set
of plants of their own, as well as of the most important
islands. But a simpler arrangement is to consider the
plant life of the earth as distributed among the following

regions :

1. The tropical zone.

2. The temperate zones.

3. The arctic zones.

4. Mountain-heights.

5. Bodies of water.

Any good geography gives some account of at least the
land vegetation of the earth. It is necessary in the pres-
ent chapter only to point out a few of the most important
characteristics of the plants of the zones and other areas
mentioned above and to give some reasons why the plant
population of each has its special characteristics.

396. Tropical Vegetation. — Within the tropics two of
the great factors of plant life and growth, namely, light
and heat, are found in a higher degree than elsewhere
on the earth. Moisture, the third requisite, is in some

1 A, Grisebach,
324

BOTANICAL GEOGRAPHY 325

regions very abundant (over sixteen feet of rainfall in a
year) or sometimes, in desert areas, almost lacking. We
find here, accordingly, the greatest extremes in amount
of vegetation, from the bare sands or rocks of the Sahara
desert (Fig. 229) to the densely wooded basin of the
Kongo and of the Amazon. Xerophytic plants, many of
them with extremely complete adaptations for supporting
life for long periods without water, are characteristic of
tropical deserts, while many of the most, decided hydro-
phytes among land-plants are found in the dripping sub-

FIG. 229. — Hills of Drifted Sand in the Sahara.

tropical forest interiors. Throughout a large part of the
zone, reaching five degrees each way from the equator,
there are daily rains the year round.

397. Vegetation of the Temperate Zones. — We are all
familiar in a general way with the nature of the plant
life of the north temperate zone ; that of the south
temperate is in most ways similar to our own. Most of
the annuals and biennials are of a medium type, not
decided xerophytes nor hydrophytes, and the perennials
are mainly tropophytes. There are no desert areas so
large or so nearly destitute of plants as those found in
subtropical regions, neither are there any such luxuriant

326

FOUNDATIONS OF BOTANY

growths as occur in the rainy forest regions of the tropics.
On the other hand, the largest trees on earth, the "big
trees," or Sequoias (Fig. 32), occur in the temperate por-
tion of North America, along the Sierra Nevada, and
the taller, though less bulky, gum trees (Eucalyptus) of
Australia grow in a warm temperate region.

398. Temperate Plant Societies due to Special Conditions
of Soil. — Even where the climate
is a moderate one as regards tem-
perature and rainfall, peculiar
soils may cause the assemblage
of exceptional plant societies.
Some of the most notable of
such societies in temperate North
America are those of the salt
marshes, the sand dunes, and the
peat bogs.

In salt marshes the water sup-
ply is abundant, but plants do not
readily absorb salt water by their
roots, so that the plants which
grow in salt marshes usually have
something of the structure and appearance of xerophytes.
Some of them are fleshy (Fig. 230), and some species are
practically leafless.

Sand dunes, whether along the seacoast or near the
great lakes, offer a scanty water supply to the roots dur-
ing much of the year, and the soil-water contains less of
the raw materials for plant food than is offered by that
of ordinary soils. Many grasses thrive, however, in these
shifting sands (Plate I), and some, like the beach-grass

FIG. 230. — A Halophytic Plant
(Salicomia).

BOTANICAL GEOGRAPHY

327

(AmmopTiild) of the Atlantic coast and the great lakes,
will continue to grow upward as the sand is piled about

them by the winds until they
have risen to a level of a
hundred feet above the start-
ing point.

Peat bogs are especially
characterized by the predominance of
the peat mosses (Fig. 231) from which
they take their name.
These plants and the others which associ-
ate with them are mostly hydrophytes, living
usually with a considerable portion of the
plant continually submerged in the bog
water. The water of such bogs contains
little mineral matter and only a very scanty
supply of nitrogen, in the form of nitrates
dissolved in it. The bog-plants, therefore,
must either get on with an exceptionally
small supply of nitrogen or they must get
it from an unusual source. The peat mosses
adopt the former alternative, while the sun
dews (Fig. 238), the pitcher-plants (Fig.
237), and some other species adopt the latter and
derive their nitrogen supply largely from insects
which they catch, kill, and digest.

399. Arctic Vegetation. — The seed-plants of the
arctic flora are mostly perennials, never trees.
gy tlie ^gQ ^\^ of the underground portion
as compared with that of the part above ground, they
are adapted to a climate in which they must lie dormant

FIG. 231.
Peat MOSS

328 FOUNDATIONS OF BOTANY

for not less than nine months of the year. The flowers
are often showy and appear very quickly after the brief
summer begins. Mosses and lichens are abundant, — the
latter of economical importance because they furnish a
considerable part of the food of reindeer.

400. Mountain or Alpine Vegetation In a general way

the effect of ascending a mountain, so far as vegetation is

FIG. 232. — A Plant of Arctic Willow. (About natural size.)

concerned, is like that of traveling into colder regions.
It was long ago suggested, in regard to Mount Ararat,
that on ascending it one traversed first an Armenian, then
a South European, then a French, then a Scandinavian,
and finally an arctic flora. Up to a certain height, which
varies in different latitudes, the slopes of mountains are
very commonly forest-covered. The altitude up to which
trees can grow (or as it is commonly called in this country
the " timber line ") is somewhat over twelve thousand feet

BOTANICAL GEOGRAPHY

329

in the equatorial Andes and lessens in higher latitudes as
one goes either way from the equator. In the White
Mountains, for instance, the timber line only rises to about
four thousand five hundred feet. The seed-plants of alpine
regions in all parts of the earth have a peculiar and charac-
teristic appearance. It is easiest to show how such plants
differ from those of the same species as they look when

FIG. 233. — Trees near the Timber Line on tlie Slope of Pikes Peak.

growing in ordinary situations by reference to the plants
themselves or to good pictures of them (see Fig. 285).
The differences between alpine and non-alpine plants of
the same or closely related species have been summed up
as follows : l

"The alpine individuals have shorter stems, smaller leaves,
more strongly developed roots, equally large or somewhat
larger and usually somewhat more deeply colored flowers,
and their whole structure is drought-loving (xerophilous)."

1 By A. F. W. Schimper.

330

FOUNDATIONS OF BOTANY

FIG. 234. — Decrease in Size of Trees at High Elevations (Canadian Rockies).

Trees at great elevations become much gnarled and
stunted, as their growth is necessarily very slow (Fig.
233). The gradual diminution of the height of the

BOTANICAL GEOGRAPHY

381

trees on ascending a mountain is well shown in Fig. 234.
The treeless character of the mountain summit is also
plain.1

Recent experiments have shown that many ordinary
plants promptly take on alpine characteristics when they
are transferred to moderate heights on mountains. For
instance, a rather
commonly culti-
vated sunflower,2
when planted at a
height of about six
thousand five hun-
dred feet, instead
of having a tall
leafy stem pro-
duces a rosette of
veiy hairy leaves
lying close to the
ground, thus be-
coming almost un-
recognizable as a
sunflower. The

Change Was even
greater than that

shown in the rock
rose (Fig. 235) cultivated by the same experimenter. The
peculiarities of alpine plants appear to be due mainly to
the intense light which they receive during the daytime,

1 Part of the diminution is only apparent, — the effect of distance, — but the
growth at the highest levels is often less than waist high.

2 Helianthus tuberosus, the so-called Jerusalem artichoke.

_ TWQ plantg Qf Kock ^^ (Helianthemum).
(Both drawn to the same scale.)

low sround form ' *• alpine form'

332 FOUNDATIONS OF BOTANY

to the strongly drying character of the air in which they
grow (due partly to its rarefaction), and to the low temper-
ature which they must endure every night.

401. Aquatic Vegetation. — Plants which live wholly in
water often need a less complicated system of organs than
land-plants. True roots may be dispensed with altogether,
as in many seaweeds, in most fresh-water algse, and in
some seed-plants. A few such plants have mere hold-
fasts that keep them from drifting with the waves or the
current. Sometimes roots may, as in the duckweeds
(Fig. 220), serve the purpose of a keel and keep the
flat, expanded part of the plant from turning bottom up.
The tissues that give strength to the stems and leaves of
land-plants are not usually much developed in submerged
aquatics, since the water supports the weight of such
plants. In some algae, as the common rockweed or blad-
der-wrack (Fig. 183), the weight of the plant is admi-
rably buoyed up by large air-bladders. Transpiration is
done away with, and whatever carbonic acid gas or oxygen
is absorbed or given off passes directly through the cell-
walls into the interiors of the cells. Generally water-
plaats do not reach any great size, but some species are
the longest of known plants, Macrocystis, the great kelp
of the Pacific Ocean, attaining, it is said, the length of a
thousand feet or more. In spite of the moderate size of
most algse the total bulk in the various oceans must be
extremely large. The Sargasso Sea alone, in the Atlantic
Ocean, reaches most of the way from the Bahamas to the
Azores and extends over seventeen degrees of latitude.
The whole area is occupied by a nearly compact mass of
floating seaweed.

BOTANICAL GEOGRAPHY 333

Besides the comparatively well-known and readily seen
larger algae there is a great amount of vegetation floating
in what is known as the plankton. This is a mass of
microscopic animals and plants, found floating scum-like
or submerged in fresh and in salt water and often accu-
mulated in great quantities near shores, to which it is
swept by the action of the wind and waves and currents.
Much of the plant life of the plankton, both of fresh and
of salt water, often consists of the flinty-shelled one-celled
microscopic algse known as diatoms (Fig. 176).

402. Botanical Geography of the United States. — All of
the continuous territory of the United States 1 lies in the
north temperate zone. There is material for a large vol-
ume in the discussion of the distribution of plants over
our territory in this continent alone, but it is possible to
sum up a mere outline of the matter in a very few words.
Excluding the floras of many single mountains and moun-
tain ranges, the land surface of the country may for botan-
ical purposes be divided into four great areas, as follows :

1. The Forest Region. — This occupies the eastern and
central portion of the United States. It is bounded on
the west by an irregular line, most of which lies to the
eastward of the hundredth meridian. In some places this
forest boundary extends eastward across the Mississippi
River, while in others it recedes from the river five
hundred miles or more to the westward.

2. The G-reat Plains Region. — This extends westward
from the region above named to the Rocky Mountain
Plateau.

1 That is, not counting in Alaska, our West Indian possessions, the Sand-
wich Islands, or the Philippines.

334 FOUNDATIONS OF BOTANY

3. The Pacific Highland Region. — This includes the
Rocky Mountains, the Sierra Nevada, and the various
plateaus between them.

4. The Pacific Slope. — This extends from the Cascade
Range and the Sierra Nevada to the sea.

403. Characteristics of the Four Regions. — The forest
region is mainly remarkable for its great variety of hard-
wood trees, of which it contains a larger number of
useful species than any equal area of the earth with a
temperate climate. In the northeasterly portion and in
much of the southerly portion there are extensive forests
of the cone-bearing evergreens, such as pines, spruces,
hemlocks, and cedars. The vegetation is in general
such as thrives in medium conditions as regards heat
and rainfall.

The plains region is largely covered with grasses, many
of them xerophytes. Some of the most characteristic plants
associated with the grasses are Composite, such as sun-
flowers, rosin-weeds (Silphium), cone-flowers, gum-weeds
(G-rindelia), and blazing-stars (Liatris).

The Pacific highland region includes a very great vari-
ety of plant societies, from the heavily wooded mountain
slopes and valleys to high sterile plains which are almost
deserts. Cone-bearing evergreen trees are very character-
istic of the forests. Great numbers of alpine species of
herbs and shrubs are found on the mountains at and above
the timber line. In the alkali regions, where the soil is
too full of mineral salts to permit ordinary plants to grow,
many kinds of xerophytes, such as the salty sage (Atriplex)
and the greasewood (Sarcobatue), occur. In the southern
portion cactuses abound.

3
CK5

P
GC
3

•JL

BOTANICAL GEOGRAPHY 335

The Pacific Slope is characterized by cone-bearing ever-
greens in great abundance in the mountains and along the
foothills. Chief among these in point of size are the red-
woods and the "big trees" (Sequoias) (Fig. 32). Oaks
are represented by a good many species, several of them
evergreen. There are many xerophytes, some of them
characteristic of alkali regions; and in Southern California,
on account of the long dry season, plants with large roots
or rootstocks and bulb-bearing plants (many of them
belonging to the lily family) are abundant. The tree
yucca (P-late VII) is one of the largest and most inter-
esting xerophytic plants of North America.

CHAPTER XXVI

PARASITES, ENSLAVED PLANTS, MESSMATES,
CARNIVOROUS PLANTS

404. Parasites. — A little was said in Chapter IV about
parasitic plants, and the life history of one of them, the
dodder, was briefly outlined ; another, the wheat rust, was
discussed in Sects. 310-313. A parasitic plant is one
which draws its supply of food partially or wholly from
another living plant or animal known as the host. Some
parasites are seed-plants, but a far greater number of
species are spore-plants.

405. Half -Parasitic Seed-Plants. — Half-parasites or par-
tial parasites are those which take a portion of their food (or
of raw materials to make food) from their host and manu-
facture the rest for themselves. Usually they take mainly
the newly absorbed soil-water from the host and do their
own starch-making by combining the carbonic acid gas,
which they absorb through their leaves, with the water
stolen by the parasitic roots or haustoria imbedded in the
wood of the host. Evidently the needed water may just
as well be taken from the underground parts of the host
as from the upper portions, and accordingly many half-
parasites are parasitic on roots. This is the case with
many of the beautiful false foxgloves (G-erardia), with the
painted-cup (Castillea), and some species of bastard toad-
flax ( Oomandra) ; see Flora. Usually these root-parasites
are not recognized by non-botanical people as parasites at

ssa

PLATE IX. — A Cottonwood covered with Mistletoe

PARASITES 337

all, but in Germany a species common in grain fields 1 and
the eyebright, which abounds in grass fields, are respectively
known as "hunger" and " milk-thief," from the injury
they do to the plants on which they fasten themselves.
The mistletoe is a familiar example of a half -parasite,
which roots on branches (Plate IX). Among the scanty
belts of cottonwood trees along streams in New Mexico it
is necessary to lop off the mistletoe every year to give the
tree any chance to grow. Half-parasites may be known
from plants that are fully parasitic by having green or
greenish foliage, while complete parasites have no chloro-
phyll and so are not at all green.

406. Wholly Parasitic Seed-Plants. — These are so nearly
destitute of the power of assimilation that they must rob
other plants of all needed food or die of starvation. Some,
like the cancer-root (see Flora), are root-parasites ; others,
like the dodder, are parasitic on stems above ground. The
most dependent species of all, such as the flax-dodder, can
live on only one kind of host, while the coarse orange-
stemmed dodder,2 which is common all over the central
and the northeastern states, grows freely on many kinds
of plants, from golden-rods to willows.

407. Parasitic Cryptogams. — The wheat rust (Sect. 310)
affords an excellent example of the relations between
parasitic fungi and their hosts. The illustration showing
the potato blight escaping from a stoma of the potato leaf
(Fig. 191) shows plainly one way in which a microscopic
parasite finds its way out of the tissues of the host-plant
to ripen and scatter its spores.

1 Alectorolophus hirsutus.

2 Cuscuta Gronovii. *

338 FOUNDATIONS OF BOTANY

Perhaps the most interesting, certainly to us the most
practically important, cases of parasitism are those in
which the bodies of animals, and especially of men, are
attacked by parasitic plants. Bacilli and other bacteria
of many species (Sect. 263) are among the commonest
parasites which use the bodies of animals as hosts, and
two or three examples will serve to illustrate how they
find a lodgment in the host.

Rich garden soil, the dust of stables, and a good many
other sources often contain immense numbers of a bacil-
lus1 which causes lockjaw. A man in cleaning harness
scratches his hand with a buckle, introduces the bacilli
into his system, and is soon taken with an attack of lock-
jaw. Sewage water often swarms with the bacilli of
typhoid fever2 (Fig. 174). The people in a city drink
unfiltered water from a river into which sewage has been
allowed to run higher up stream, the bacilli multiply at a
rapid rate in the intestines of those who have drunk the
water, and many of them are taken sick with typhoid
fever. The phlegm expectorated by consumptive patients
is full of the consumption bacillus ; 3 this phlegm becomes
dried up on floors, streets, or sidewalks, it is breathed by
every one in the form of fine dust, and in the lungs of
many who breathe it colonies of the bacillus are formed
and the disease (consumption) becomes established in
these persons.

408. Enslaved Plants. — Cases in which one kind of
plant is useful in procuring food (or the raw materials
of food) for another kind are quite oommon.

The relations on which algse and fungi live together in

1 Bacillus tetani. * 2 Bacillus typhi. 8 Bacillus tuberculosis.

PARASITES

339

the form of lichens have already been described (Sect. 331).
It is not correct to describe the condition of such algae
as slavery if the term is meant to imply that they derive
no benefit from the association. Perhaps serfdom is a

— -t

FIG. 236. — Roots of Red Clover with Tubercles.

/, sections of ascending branches ; 6, enlarged base of stem ; t, root-tubercles
containing bacteria.

more suitable word, though it is not the term used by
botanists. At all events, the alga is enclosed within a
network of fungus hyphae from which it cannot readily
escape, and there does most of the work of the lichen,
including all of the manufacture of food from carbon
dioxide.

340

FOUNDATIONS OF BOTANY

409. Messmates.1 — Plants of very diverse character,
which live most intimately together to the advantage of
both parties, may be called messmates, since in some fashion

or other they divide the
food supply between
them.

Bacteria live in col-
onies enclosed in root-
tubercles on the roots of
certain plants, for in-
stance, beans, peas, lu-
pines, vetches, and clover
(Fig. 236), and render
the greatest service to
the plant to which the
roots belong, from which
they also derive food and
shelter. Such plants do
not develop root-
tubercles and will not
grow well in sterilized
soil, that is, soil in which
the bacteria have been

FIG. 237. — Common Pitcher-Plant.2 killed by baking. It is

At the right one of the pitcher-like leaves is foun^ that the bacteria
shown in cross-section.

serve to change nitrogen

taken from the air of the soil into nitric acid, which is a

most important ingredient in the manufacture of proteids.

Many trees, for example, oaks, beeches, and the cone-

1 This term is borrowed from the zoologists as a much simpler one than
symbionts to express the relation variously known as symbiosis, commensalism,
or mutualism. 2 Sarracenia purpurea.

INSECTIVOROUS PLANTS

341

FIG. 238. — Sundew (Drosera rotundifolia).

bearing evergreens, and a considerable number of herbaceous
plants, such as the Indian pipe (Monotropa, Plate V),
are covered with a growth of fungus hyphse (Sect. 307).

342

FOUNDATIONS OF BOTANY

FIG. 239. — Blade of Leaf
of Sundew. (Somewhat
magnified.)

This growth completely surrounds the
young, active tips of all the roots and
the threads of the mykorhiza, as it is
called, seem to do the work of root-
hairs.

410. Carnivorous Plants. — In the
ordinary pitcher-plants (Fig. 237) the
leaf appears in the shape of a more or
less hooded pitcher. These pitchers
are usually partly filled with water,
and in this water very many drowned
and decaying insects are commonly
to be found. The insects have flown
or crawled into the pitcher, and, once inside, have been
unable to escape on account of the dense growth of bristly
hairs about the mouth, all pointing inward and downward.
How much the com-
mon American pitcher-
plants depend for
nourishment on the
drowned insects in the
pitchers is not defi-
nitely known, but it is
certain that some of
the tropical species re-
quire such food.1

In other rather com-
mon plants, the sun-
dews, insects are

FIG. 240. — Leaves of Sundew. (Somewhat

magnified.)

The one at the left has all its tentacles closed
over captured prey ; the one at the right has
only half of them thus closed.

1 Where the Sarracenia is abundant it will be found interesting and profit-
able to make a careful class study of its leaves. See Geddes, Chapters in
Modern Botany, Chapters I and II.

INSECTIVOROUS PLANTS

343

caught by a sticky secretion which proceeds from hairs on
the leaves. In one of the commonest sundews the leaves
consist of a roundish blade, borne on a moderately long
petiole. On the inner surface and round the margin of
the blade (Fig. 239) are borne a considerable number of
short bristles, each ter-
minating in a knob which
is covered with a clear,
sticky liquid. When a
small insect touches one
of the sticky knobs, he
is held fast and the hairs
at once begin to close
over him, as shown in
Fig. 240. Here he soon
dies and then usually re-
mains for many days,
while the leaf pours out
a juice by which the
soluble parts of the insect
are digested. The liquid
containing the digested
portions is then absorbed
by the leaf and contrib-
utes an important part of the nourishment of the plant,
while the undigested fragments, such as legs, wing-cases,-
and so on, remain on the surface of the leaf or may drop
off after the hairs let go their hold on the captive insect.

In the Venus flytrap, which grows in the sandy regions
of eastern North Carolina, the mechanism for catching
insects is still more remarkable. The leaves, as shown in

FIG. 241. — Venus Flytrap.

344 FOUNDATIONS OF BOTANY

Fig. 241, terminate in a hinged portion which is surrounded
by a fringe of stiff bristles. On the inside of each half
of the trap grow three short hairs. The trap is so sensi-
tive that when these hairs are touched it closes with a jerk
and very generally succeeds in capturing the fly or other
insect which has sprung it. The imprisoned insect then
dies and is digested, somewhat as in the case of those
caught by the sundew, after which the trap reopens and
is ready for fresh captures.

411. Object of catching Animal Food. — It is easy to
understand why a good many kinds of plants have taken
to catching insects and absorbing the digested products.
Carnivorous, or flesh-eating, plants belong usually to one
of two classes as regards their place of growth ; they are
bog-plants or air-plants. In either case their roots find it
difficult to secure much nitrogen-containing food, that is,
much food out of which proteid material can be built up.
Animal food, being itself largely proteid, is admirably
adapted to nourish the growing parts of plants, and those
which could develop insect-catching powers would stand
a far better chance to exist as air-plants or in the thin,
watery soil of bogs than plants which had acquired no
such resources.

CHAPTER XXVII
HOW PLANTS PROTECT THEMSELVES FROM ANIMALS

412. Destruction by Animals. — All animals are sup-
ported directly or indirectly by plants. In some cases the
animal secures its food without much damaging the plant
on which it feeds. Browsing on the lower branches of a
tree may do it little injury, and grazing animals, if not
numerous, may not seriously harm the pasture on which
they feed. Fruit-eating animals may -even be of much
service by dispersing seeds (Sect. 458). But seed-eating
birds and quadrupeds, animals which, like the hog, dig up
fleshy roots, rootstocks, tubers or bulbs, and eat them,
or animals which, like the sheep, graze so closely as to
expose the roots of grasses or even of forest trees to be
parched by the sun, destroy immense numbers of plants.
So too with wood-boring and leaf-eating insects, and snails,
which consume great quantities of leaves.

413. Some Modes of Protection from Animals. — Many
of the characteristics of plants may be wholly or partly
due to adaptations for protective purposes, while in par-
ticular cases we cannot be sure of the fact. Perching on
lofty rocks or on branches of trees, burying the perennial
part (bulb, rootstock, etc.) underground, growing in dense
masses, like a canebrake or a thicket of blackberry bushes ;
all such habits of plants may be partly or altogether val-
uable to the plant as means of avoiding the attacks of
animals, but this cannot be proved. On the other hand,

345

346 FOUNDATIONS OF BOTANY

there are plenty of instances of structures, habits, or accu-
mulations of stored material in their tissue which plants
seem to have acquired mainly or entirely as means of
defense. Some of the most important are:

(1) The habit of keeping a bodyguard of ants.

(2) Mimicking the appearance of dangerous or uneatable plants, or

imitating pebbles or earth, so that they may be overlooked.

(3) Forming tough, corky, woody, limy or flinty and therefore

nearly uneatable tissue.

(4) Arming exposed parts with cutting edges, sharp or stinging

hairs, prickles, or thorns.

(5) Accumulating unpleasant or poisonous substances in exposed

parts.

414,- Ant-Plants. — Some ants live on vegetable food,
but most of them eat only animal food, and these latter
are extremely voracious. It has been estimated by a
careful scientist, an authority on this subject, that the
ants of a single nest sometimes destroy as many as one
hundred thousand insects in a day. The Chinese orange-
growers in the Province of Canton have found how useful
ants may be as destroyers of other insects, and so they
place ant nests in the orange trees and extend bamboos
across from one tree to another, to serve as bridges for the
ants to travel on.

Certain tropical trees, in order to insure protection by
ants, offer them especial inducements to establish colonies
on their trunks and branches. The attractions which are
offered to ants by various kinds of trees differ greatly.
One of the most interesting adaptations is that of an
acacia1 (Fig. 242), which furnishes little growths at the
ends of the leaflets which serve as ant food. These little

1 A. sphaerocephala.

HOW PLANTS PROTECT THEMSELVES

347

growths are known from their discoverer as Belt's bodies.
The ants bore holes into the large hollow stipular thorns
shown in the figure, live in these thorns, feed on the
Belt's bodies, and protect the acacia from insect and other
enemies. A nectary on the leaf furnishes additional food
to the ant inhabitants of the tree. A great multitude of
plants, some of them herbs, offer more or less important

leaflet

PIG. 242. — An Ant-Plant (Acacia).
t, thorns ; h, hole in thorn ; n, nectary ; b, Belt's body on tip of leaflet.

inducements to attract ant visitors ; the species which are
known to do this number over three thousand.

415. Plants which mimic Plants or Other Objects. —
Instances of mimicry of protected plants by unprotected
species are not very common. One of the best-known
cases is that of the dead-nettle, which is so called because
it looks like the stinging nettle, though it is perfectly
harmless. Some South African plants (Kleinias) appear
to mimic pebbles. Certain Mesembryanthemums of the

348

FOUNDATIONS OF BOTANY

same region can hardly be distinguished from the earth in
which they grow.

416. Plants of Uneatable Texture. — Whenever tender
and juicy herbage is to be had, plants of hard and stringy
texture are left untouched. The flinty-stemmed scouring-
rushes (Equisetum, Sect. 361) and the dry, tough rushes
are familiar examples of uneatable plants of damp soil.
In pastures there grow such peren-
nials as the bracken fern and the
hardback of New England and the
iron weed and vervains of the Cen-
tral States, which are so harsh and
woody that the hungriest browsing

FIG. 243. — Spiny Leaves of Barberry.

animal is rarely, if ever, seen to molest them. Still other
plants, like the knotgrass and cinquefoil of our dooryards,
are doubly safe, from their growing so close to the ground
as to be hard to graze and from their woody and unpala-
table nature. The date-palm (which can easily be raised
from the seed in the schoolroom or the laboratory) is an
excellent instance of the same uneatable quality, found
in a tropical or sub-tropical plant.

HOW PLANTS PROTECT THEMSELVES

349

417. Plants with Weapons for Defense.1 — Multitudes
of plants, which might otherwise have been subject to the
attacks of grazing or browsing animals, have acquired
what have with reason been called weapons. Shrubs and
trees not infrequently produce sharp-pointed branches,
familiar in our own crab-apple, wild plum, thorn trees,
and above all in the honey locust (Fig. 34), whose formida-
ble thorns often branch in

a very complicated man-
ner.

Thorns, which are
really modified leaves, are
very perfectly exempli-
fied in the barberry (Fig.
243). It is much com-
moner to find the leaf
extending its midrib or
its veins out into spiny
points, as the thistle does, or bearing spines or prickles on
its midrib, as is the case with the nightshade shown in Fig.
244, and with so many roses. Prickles, which are merely
hard, sharp-pointed projections from the epidermis, are of
too common occurrence to need illustration.

Stipules are not infrequently found occurring as thorns,
and in our common locust (Fig. 246) the bud, or the very
young shoot which proceeds from it, is admirably pro-
tected by the jutting thorn on either side.

418. Pointed, Barbed, and Stinging Hairs. — Needle-
pointed hairs are an efficient defensive weapon of many
plants. Sometimes these hairs are roughened, like those

1 See Kerner and Oliver's Natural History of Plants, Vol. I, p. 430.

FIG. 244. — Leaf of a Night-
shade (Solatium atropur-
pureurri).

350

FOUNDATIONS OF BOTANY

of the bugloss (Fig. 247, b) ; sometimes they are decidedly
barbed. If the barbs are well developed they may cause
the hairs to travel far into the flesh of animals and cause
intense pain. In the nettle (Fig. 247, a) the hairs are
efficient stings, with a brittle tip, which on breaking off

FIG. 246. — Thorn
Stipules of Locust.

FIG. 245. — Euphorbia splendens.

The spines are dead and dry

stipules.

exposes a sharp, jagged
tube full of irritating

fluid. These tubular hairs,

with their poisonous contents,

will be found sticking in the

skin of the hand or the face
after incautious contact with nettles, and the violent itching
which follows is only too familiar to most people.

419. Cutting Leaves. — Some grasses and sedges are
generally avoided by cattle because of the sharp-cutting
edges of their leaves, which will readily slit the skin of
one's hand if they are drawn rapidly through the fingers.
Under the microscope the margins of such leaves are seen
to be regularly and thickly set with sharp teeth like those
of a saw (Fig. 247, c, d).

HOW PLANTS PROTECT THEMSELVES

351

420. Weapons of Desert Plants. — In temperate regions,
where vegetation is usually abundant, such, moderate
means of protection as have just been described are gener-
ally sufficient to insure the safety of the plants which have
developed them. But in desert or semi-desert regions the

FIG. 247. — Stinging Hairs and Cutting Leaves. (All much magnified.)

a, stinging hairs on leaf of nettle ; b, bristle of the bugloss ; c, barbed margin

of a leaf of sedge ; d, barbed margin of a leaf of grass.

extreme scarcity of plant life exposes the few plants that
occur there to the attacks of all the herbivorous animals
that may encounter them. Accordingly, great numbers of
desert plants are characterized by nauseating or poisonous
qualities or by the presence of astonishingly developed
thorns, while some combine both of these means of defense.

352 FOUNDATIONS OF BOTANY

421. Offensive or Poisonous Plants. — A disgusting smell
is one of the common safeguards which keep plants from
being eaten. The dog fennel (Fig. 227), the hound's-tongue
(Cynoglossum), the Martynia, and the tomato-plant are
common examples of rank-smelling plants which are offen-
sive to most grazing animals and so are let alone by them.
Oftentimes, as in the case of the jimson weed (Datura),
the tobacco-plant, and the poison hemlock (Conium), the
smell serves as a warning of the poisonous nature of the
plant.

A bitter, nauseating, or biting taste protects many plants
from destruction by animals. Buckeye, horse-chestnut,
and maple twigs and leaves are so bitter that browsing
animals and most insects let them alone. Tansy, ragweed,
boneset, southernwood, and wormwood are safe for the
same reason. The nauseous taste of many kinds of leaves
and stems, such as those of the potato, and the fiery taste
of pepper-corns, red peppers, mustard, and horse-radish,
make these substances uneatable for most animals. Prob-
ably both the smell and the taste of onions serve to insure
the safety of the bulbs from the attacks of most grubs,
and the hard corm of the jack-in-the-pulpit (Ariscema)
(Frontispiece) is carefully let alone on account of the
blistering nature of its contents.

Poisonous plants are usually shunned by grown-up
animals, though the young ones will sometimes eat such
plants and may be killed by them. Almost any part of a
poisonous species may contain the poison characteristic of
the plant, but, for obvious reasons, such substances are
especially apt to be stored in the parts of the plant where
its supply of reserve food is kept.

CHAPTER XXVIII
ECOLOGY OF FLOWERS

422. Topics of the Chapter. — The ecology of flowers is
concerned mainly with the means by which the transfer-
ence of pollen or pollination is effected, and with the ways
in which pollen is kept away from undesirable insect
visitors and from rain.

423, Cross-Pollination and Self -Pollination. — It was
long supposed by botanists that the pollen of any perfect
flower needed only to be placed on the stigma of the same
flower to insure satisfactory fertilization. But in 1857
and 1858 the great English naturalist, Charles Darwin,
stated that certain kinds of flowers were entirely dependent
for fertilization on the transference of pollen from one
plant to another, and he and other botanists soon extended
the list of such flowers until it came to include most of
the showy, sweet-scented, or otherwise conspicuous kinds.
It was also shown that probably nearly all attractive
flowers, even if they can produce some seed when self-
pollinated, do far better when pollinated from the flowers
of another plant of the same kind.1 This important fact
was established by a long series of experiments on the
number and vitality of seeds produced by a flower when
treated with its own pollen, or self-pollinated, and when

1 See Darwin's Cross and Self-Fertilization in the Vegetable Kingdom
(especially Chapters I and II).

353

354 FOUNDATIONS OF BOTANY

treated with pollen from another flower of the same kind,
or cross-pollinated.1

424. Wind-Pollinated Flowers.2 — It has already been
mentioned that some pollen is dry and powdery, and
other kinds are more or less sticky. Pollen of the dusty
sort is light, and therefore adapted to be blown about
by the wind. Any one who has been much in corn-
fields after the corn has " tasseled " has noticed the pale
yellow dusty pollen which flies about when a cornstalk is
jostled, and which collects in considerable quantities on
the blades of the leaves. Corn is
monoecious, but fertilization is best
accomplished by pollen blown from
the "tassel" (stamens) of one plant

FIG. M8.-Ptatil of a Grass, b • • d ^ ^ u ^ „ (pistils)

provided with a Feathery

stigma, adapted for wind- of another plant. This is well
shown by the fact, familiar to every

observing farmer's boy, that solitary cornstalks, such as
often grow very luxuriantly in an unused barnyard or
similar locality, bear very imperfect ears or none at
all. The common ragweed, another monoecious plant,
is remarkable for the great quantities of pollen which
shake off it on to the shoes or clothes of the passer-by,
and it is wind-pollinated. So, too, are the monoecious
pines, and these produce so much pollen that it has been
mistaken for showers of sulphur, falling often at long dis-
tances from the woods where it was produced. The pistil
of wind-pollinated flowers is often feathery and thus
adapted to catch flying pollen-grains (Fig. 248). Other

1 On dispersion of pollen see Kerner and Oliver, Vol. II, pp. 129-287.

2 See Miss Newell's Botany Reader, Part II, Chapter VII.

ECOLOGY OF FLOWERS 355

characteristics of such flowers are the inconspicuous char-
acter of their perianth, which is usually green or greenish,
the absence of odor and of nectar, the regularity of the
corolla, and the appearance of the flowers before the leaves
or their occurrence on stalks raised above the leaves.

Pollen is, in the case of a few aquatic plants, carried
from flower to flower by the water on which it floats.

425. Insect-Pollinated Flowers. — Most plants which
require cross-pollination depend upon insects as pollen-
carriers,1 and it may be stated as a general fact that the
showy colors and markings of flowers and their odors all
serve as so many advertisements of the nectar (commonly
but wrongly called honey) or of the nourishing pollen
which the flower has to offer to insect visitors.

Many insects depend mainly or wholly upon the nectar
and the pollen of flowers for their food. Such insects
usually visit during any given trip only one kind of flower,
and therefore carry but one kind of pollen. Going straight
from one flower to another with this, they evidently waste
far less pollen than the wind or water must waste. It is
therefore clearly advantageous to flowers to develop such
adaptations as fit them to attract insect visitors, and to
give pollen to the latter and receive it from them.

426. Pollen-Carrying Apparatus of Insects.2 — Ants and
some beetles which visit flowers have smooth bodies, to
which little pollen adheres, so that their visits are often of
slight value to the flower, but many beetles, all butterflies
and moths, and most bees have bodies roughened with
scales or hairs which hold a good deal of pollen entangled.

1 A few are pollinated by snails ; many more by humming-birds and other
birds. 2 gee Muller's Fertilization of Flowers, Part II.

356

FOUNDATIONS OF BOTANY

In the common honey-bee (and in many other kinds) the
greater part of the insect is hairy, and there are special
collecting baskets, formed by bristle-like hairs, on the hind

legs (Fig. 249). It is easy
to see the load of pollen
accumulated in these bas-
kets after such a bee has
visited several flowers. Of
course the pollen which the
bee packs in the baskets and
carries off to the hive, to be
stored for food, is of no use
in pollination. In fact such
FIG. 249. pollen is in one sense entirely

A, right hind leg of a honey-bee (seen from wasted. But since Such
behind and within) ; J3, the tibia, ti,
seen from the outside, showing the col- bees as have these Collect-

lecting basket formed of stiff hairs.

are the

industrious visitors to flowers, they accomplish an immense
share of the work of pollination by means of the pollen
grains which stick to their hairy coats and are then trans-
ferred to other flowers of the same kind next visited by
the bee.

427, Nectar and Nectaries. — Nectar is a sweet liquid
which flowers secrete for the purpose of attracting insects.
After partial digestion in the crop of the bee, nectar
becomes honey. Those flowers which secrete nectar do
so by means of nectar glands, small organs whose structure
is something like that of the stigma, situated often near
the base of the flower, as shown in Fig. 250. Sometimes
the nectar clings in droplets to the surface of the nectar
glands ; sometimes it is stored in little cavities or pouches

ECOLOGY OF FLOWERS

357

called nectaries. The pouches at the bases of columbine
petals are among the most familiar of nectaries.

428. Odors of Flowers. — The acuteness of the sense of
smell among insects is a familiar fact. Flies buzz about
the wire netting which covers a piece of fresh meat or a
dish of syrup, and bees, wasps, and hornets will fairly
besiege the window screens of a kitchen where preserving
is going on. Many plants find it possible to attract as
many insect visitors as they need without giving off any
scent, but small flowers, like the mignonette, and night-
blooming ones, like the white tobacco and the evening
primrose, are sweet-scented to attract night-flying moths.
It is interesting to observe that the majority of the flowers
which bloom at night are white, and that they are much
more generally sweet-scented than flowers which bloom
during the day. A few flowers are
carrion-scented (and purplish or brown-
ish colored) and attract flies.

429. Colors of Flowers. — Flowers
which are of any other color than green
probably in most cases display their
colors to attract insects, or occasionally
birds. The principal color of the flower
is most frequently due to showy petals;
sometimes, as in the marsh marigold, it
belongs to the sepals; and not infre-
quently, as in some cornels and Eu-
phorbias (Fig. 245), the involucre is more brilliant and
conspicuous than any part of the flower strictly so called.

Different kinds of insects appear to be especially
attracted by different colors. In general, dull yellow,

FIG. 250. — Stamens and
Pistil of the Grape
(magnified), with a
Nectar Gland, g, be-
tween Each Pair of
Stamens.

358 FOUNDATIONS OF BOTANY

brownish, or dark purple flowers, especially if small, seem
to depend largely on the visits of flies. Red, violet, and
blue are the colors by which bees and butterflies are most
readily enticed. The power of bees to distinguish colors
has been shown by a most interesting set of experiments
in which daubs of honey were put on slips of glass laid on
separate pieces of paper, each of a different color, and
exposed where bees would find them.1

It is certain, however, that colors are less important
means of attraction than odors from the fact that insects
are extremely near-sighted. Butterflies and moths cannot
see distinctly at a distance of more than about five feet,
bees and wasps at more than two feet, and flies at more
than two and a fourth feet. Probably no insects can make
out objects clearly more than six feet away.2 Yet it is
quite possible that their attention is attracted by colors at
distances greater than those mentioned.

430. Nectar Guides. — In a large number of cases the
petals of flowers show decided stripes or rows of spots, of
a color different from that of most of the petal. These
commonly lead toward the nectaries, and it is possible that
such markings point out to insect visitors the way to the
nectaries. Following this course, the insect not only
secures the nectar which he seeks, but probably leaves
pollen on the stigma and becomes dusted with new pollen,
which he carries to another flower.

431. Facilities for Insect Visits. — Regular polypetalous
flowers have no special adaptations to make them singly

1 See Lubbock's Flowers, Fruits, and Leaves, Chapter 1. On the general
subject of colors and odors in relation to insects, see Miiller's Fertilization of
Flowers, Part IV.

2 See Packard's Text-Book of Entomology, p. 260.

ECOLOGY OF FLOWERS

359

accessible to insects, but they lie open to all comers.
They do, however, make themselves much more attractive
and afford especial inducements in the matter of saving
time to flower-frequenting insects by being grouped. This
purpose is undoubtedly served by dense flower-clusters,
especially by heads like those of the clovers and by the
peculiar form of head found in so-called composite flowers,
like the sunflower, the bachelor's button, and the yarrow
(Fig. 133). In many such clusters the flowers are special-
ized, some carrying a showy strap-
shaped corolla, to serve as an
advertisement of the nectar and
pollen contained in the inconspicu-
ous tubular flowers (see Plate XI).
Irregular flowers probably always
are more or less adapted to par-
ticular insect (or other) visitors.
The adaptations are extremely nu-
merous ; — here only a very few of
the simpler ones will be pointed
out. Where there is- a drooping
lower petal (or, in the case of a gamopetalous corolla, a
lower lip), this serves as a perch upon which flying insects
may alight and stand while they explore the flower, as the
beetle is doing in Fig. 251. In Fig. 252 one bumblebee
stands with his legs partially encircling the lower lip of
the dead-nettle flower, while another perches on the sort
of grating made by the stamens of the horse-chestnut
flower. The honey-bee entering the violet clings to the
beautifully bearded portion of the two lateral petals, while
it sucks the nectar from the spur beneath.

FIG. 251. —A Beetle on the

Flower of the Twayblade.

(Enlarged three times.)

360

FOUNDATIONS OF BOTANY

432. Protection of Pollen from Unwelcome Visitors. — It
is usually desirable for the flower to prevent the entrance
of small creeping insects, such as ants, which carry little
pollen and eat a relatively large amount of it. The means
adopted to secure this result are many and curious. In

FIG. 252. — Bees visiting Flowers.

At the left a bumblebee on the flower of the dead nettle ; below a similar
bee in the flower of the horse-chestnut ; above a honey-bee in the flower
of a violet.

some plants, as the common catchfly, there is a sticky
ring about the peduncle, some distance below the flowers,
and this forms an effectual barrier against ants and like
insects. Very frequently the calyx tube is covered with
hairs, which are sometimes sticky. How these thickets
of hairs may appear to a very small insect can perhaps
be more easily realized by looking at the considerably

ECOLOGY OF FLOWERS 361

magnified view of the hairs from the outer surface of
mullein petals, shown in Fig. 25 3. 1

Sometimes the recurved petals or divisions of the corolla
stand in the way of. creeping insects. In other cases the

FIG. 253. — Branching Hairs from the Outside of the Corolla of the Common
Mullein. (Magnified.) dr, a gland.

FIG. 254. — A Sphinx Moth, with a Long Sucking-Tube.

throat of the corolla is much narrowed or closed by hairs,
or by appendages. Those flowers which have one or more

1 On protection of pollen, see Kerner and Oliver, Vol. II, pp. 95-109.

362 FOUNDATIONS OF BOTANY

sepals or petals prolonged into spurs, like the nasturtium
and the columbine, are inaccessible to most insects except
those which have a tongue or a sucking-tube long enough
to reach to the nectary at the bottom of the spur. The
large sphinx moth, shown in Fig. 254, which is a common
visitor to the flowers of the evening primrose, is an
example of an insect especially adapted to reach deep into
long tubular flowers.

A little search among flowers, such as those of the
columbine or the foxglove, will usually disclose many
which have had the corolla bitten through by bees, which
are unable to get at the nectar by fair means or unwilling .
to take the trouble to do so ; and they therefore steal it.

433. Bird-Pollinated Flowers. — Some flowers with very
long tubular corollas depend entirely upon birds to carry
their pollen for them. Among garden flowers the gladi-
olus, the scarlet salvia, and the trumpet honeysuckle are
largely dependent upon humming-birds for their pollination.
The wild balsam or jewel-weed and the trumpet-creeper
(Plate X) are also favorite flowers of the humming-bird.

434. Prevention of Self -Fertilization. — Dioecious flowers
are of course quite incapable of self-pollination. Pistillate
monoecious flowers may be pollinated by staminate ones
on the same plant, but this does not secure as good seed
as is secured by having pollen brought to the pistil from
a different plant of the same kind.

In perfect flowers self-pollination would commonly occur
unless it were prevented by the action of the essential
organs or by something in the structure of the flower. In
reality many flowers which at first sight would appear to
be designed to secure self-pollination are almost or quite

ECOLOGY OF FLOWERS

363

incapable of it. Frequently the pollen from another plant
of the same species prevails over that which the flower
may shed on its own pistil, so that when both kinds are
placed on the stigma at the same time it is the foreign
pollen which causes fertilization. But apart from this
fact there are several means of insuring the presence of
foreign pollen, and only that, upon the stigma, just when
it is mature enough to
receive pollen tubes.

435. Stamens and Pistils
maturing at Different
Times. — If the stamens
mature at a different time
from the pistils, self-polli-

nation is. as effectually pre-
vented as though the plant
were dioecious. This un-
equal maturing or dichog-
amy occurs in many kinds

Of flowers. In SOme, the

fig WOrt and the Common In A (earlier stage) the stamens are mature,

while the pistil is stm undevel°Ped and bent

to one side. In B (later stage) the stamens
have withered and the stigmas have sepa-
rated, ready for the reception of pollen.

255' -™°™ '<* Cterodendronin Two

plantain for example, the

pistil develops before the

•i TT .,

stamens, but usually the
reverse is the case. The Clerodendron,1 a tropical African
flower (Fig. 255), illustrates in a most striking way the
development of stamens before the pistil. The insect visitor,
on its way to the nectary, can hardly fail to brush against
the protruding stamens of the flower in its earlier stage
(at J.), but it cannot deposit any pollen on the stigmas,

1 C. Thompsoniae.

364

FOUNDATIONS OF BOTANY

which are unripe, shut together, and tucked aside out of
reach. On flying to a flower in the later stage the pollen
just acquired will be lodged on the prominent stigmas and
thus produce the desired cross-pollination.

--sag

I II III IV

FIG. 256. — Provisions for Cross-Pollination in the High Mallow.

I, essential organs as found in the bud ; II, same in the staminate stage, the
anthers discharging pollen, pistils immature ; III, intermediate stage,
slig, the united stigmas ; IV, pistillate stage, the stigmas separated,
stamens withered.

Closely related flowers often differ in their plan of
pollination. The high mallow, a plant cultivated for its
purplish flowers, which has run wild to some extent, is
admirably adapted to secure cross-pollination, since when
its stamens are shedding pollen, as in
Fig. 256, II, the pistils are incapable of
receiving it, while when the pistils are
mature, as at IV, the stamens are quite
withered. In the common low mallow
of our dooryards and waysides insect
pollination may occur, but if it does not

FIG. 257. — Stamens *'

and Pistils of Round- the curling stigmas finally come in con-
Leafed Maiiow. The il(ici ^fa ih& projectmg stamens and

stignvas curled round

among the stamens receive pollen from them, as is indicated

to admit of self-pol- . T-,. ctrn
lination. "1 tig. 257.

ECOLOGY OF FLOWERS

365

436. Movements of Floral Organs to aid in Pollination.

— Besides the slow movements which the stamens and
pistil make in such cases as those of the Clerodendron and
the mallow, already described, the parts of the flower
often admit of considerable and rather quick movements
to assist the insect visitor to become dusted or smeared
with pollen.

In some flowers whose stamens perform rapid move-
ments when an insect enters, it is easy to see how directly

FIG. 258. — Two Flowers of Common Sage, one of them visited by a Bee.

useful the motion of the stamens is in securing cross-
pollination. The stamens of the laurel, Kalmia, throw
little masses of pollen, with a quick jerk, against the
body of the visiting insect. Barberry stamens spring up
against the visitor and dust him with pollen. The common
garden sage matures its anthers earlier than its stigmas.
In Fig. 258, A, the young flower is seen, visited by a bee,
and one anther is shown pressed closely against the side
of the bee's abdomen. The stigma, st, is hidden within
the upper lip of the corolla. In B, an older flower, the

366

FOUNDATIONS OF BOTANY

anthers have withered and the stigma is now lowered so
as to brush against the body of any bee which may enter.

A little study of Fig. 259
will make clear the way
in which the anthers are
hinged, so that a bee strik-

FIG. 259. — Flower and Stamens of Common Sage.

A, p, stigma ; a, anthers ; B, the two stamens in ordinary position ; /, filaments ;
m, connective (joining anther-cells) ; a', anther-cells ; C, the anthers and
connectives bent into a horizontal position by an insect pushing against a.

ing the
bearing
will lie

empty or barren anther-lobes, a, knocks the pollen-
lobes, a\ into a horizontal position, so that they
closely pressed against either side of its abdomen.

437, Flowers with Sta-
mens and Pistils Each of Two
Lengths. — The flowers of
bluets, partridge-berry, the
primroses, and a few other
common plants secure cross-
pollination by having essen-
tial organs of two forms
(Fig. 260). Such flowers
are said to be dimorphous
(of two forms). In the
short-styled flowers, II, the
anthers are borne at the top
of the corolla tube and the

FIG. 260. — Dimorphous Flowers of

the Primrose.
i, a *>•**" n' a short-

ECOLOGY OF FLOWERS 367

stigma stands about halfway up the tube. In the long-
styled flowers, I, the stigma is at the top of the tube and
the anthers are borne about halfway up. An insect pressing
its head into the throat of the corolla of II would become
dusted with pollen, which would be brushed off on the
stigma of a flower like I. On leaving a long-styled flower
the bee's tongue would be dusted over with pollen, some
of which would necessarily be rubbed off on the stigma of
the next short-styled flower that was visited. Cross-polli-
nation is insured, since all the flowers on a plant are of
one kind, either long-styled or short-styled, and since the
pollen is of two sorts, each kind sterile on the stigma of
any flower of similar form to that from which it came.

Trimorphous flowers, with long, medium, and short
styles, are found in a species of loosestrife.1

438. Studies in Insect Pollination. — The student cannot gather
more than a very imperfect knowledge of the details of cross-polli-
nation in flowers without actually watching some of them as they
grow, and observing their insect visitors. If the latter are caught
and dropped into a wide-mouthed stoppered bottle containing a bit
of cotton saturated with chloroform, they will be painlessly killed,
and most of them may be identified by any one who is familiar with
our common insects. The insects may be observed and classified
in a general way into butterflies, moths, bees, flies, wasps, and beetles,
without being captured or molested.

Whether these out-of-door studies are made or not, several flowers
should be carefully examined and described as regards their arrange-
ments for attracting and utilizing insect visitors (or birds). The
following list includes a considerable number of the most accessible
flowers of spring and early summer, about which it is easy to get
information from books.

1 See Miss NewelFs Reader in Botany, Part II, pp. 60-63.

368 FOUNDATIONS OF BOTANY

LIST OF INSECT-POLLINATED FLOWERS.1

1. Flax Linum usitatissimum Mull.

2. Missouri currant . Eibes aureum Mull.

3. Snowberry . . . Symphoricarpus racemosus .... Mull.

4. Lilac Syringa persica .... I ... Mull.

5. Periwinkle . . . Vinca minor Mull.

6. Mignonette . . . Reseda odorata Mull.

7. Pansy Viola tricolor Miill.

8. Dead nettle . . . Lamium album Lubbock.

9. Bleeding heart . . Dicentra (Diclytra) spectabilis . . . Miill.

10. Columbine . . . Aquilegia vulgaris ....... Miill.

11. Monkshood . . . Aconitum Napellus Mull.

12. Larkspur .... Delphinium elatum, D. consolida . . Miill.

13. Herb Robert . . . Geranium robertianum ...... Mull.

14. Pink Dianthus (various species) .... Miill.

15. Fireweed .... Epilobium angustifolium Gray.

16. Nasturtium . . . Tropceolum majus . . . Newell, Lubbock.

17. Lily-of -the- valley . Convallaria majalis Miill.

18. Heal-all .... Brunella (Prunella) vulgaris .... Miill.

19. Ground ivy . . . Nepeta Glechoma .... Miill., Newell.

20. Lousewort . . . Pedicular is canadensis . . . Miill., Newell.

21. Snapdragon . . . Antirrhinum majus Miill.

22. Iris Iris versicolor Newell.

23. Bellflower . . . Campanula rapunculoides .... Miill.

24. Horse-chestnut . . ^sculus Hippocastanum .... Newell.

1 The plants in this list are arranged somewhat in the order of the com-
plexity of their adaptations for insect pollination, the simplest first. It would
be well for each student to take up the study of the arrangements for the
utilization of insect visitors in several of the groups above, numbered with
Roman numerals. The teacher will find explanations of the adaptations in
the works cited by abbreviations at the right. Miill. stands for Miiller's Fer-
tilization of Flowers; Lubbock, for British Wild Flowers, considered in
Relation to Insects; Gray, for Gray's Structural Botany; and Newell, for
Miss Newell's Outlines of Lessons in Botany, Part II. Consult also Weed's
Ten New England Blossoms. » «

ECOLOGY OF FLOWERS

369

III

25. Yarrow Achillea millefolium Mull.

26. Oxeye daisy . . . Chrysanthemum Leucanthemum . . . Miill.

27. Dandelion . . . Taraxacum officinale . . . Mull., Newell.

28. Barberry .... Berberis vulgaris Lubbock.

29. Mountain laurel . Kalmia latifolia Gray.

30. White clover .

31. Ked clover .

32. Locust.

33. Wistaria . .

34. Vetch . . .

35. Pea. . . .

36. Bean . . .

37. Ground-nut .

38. Partridge-berry .

39. Primrose . * .

40. Loosestrife .

41. Milkweed.

42. Lady's-slipper .

Trifolium repens Mull.

Trifolium pratense Mull.

Robinia Pseudacacia Gray.

Wistaria sinensis Gray.

Vicia cracca Miill.

Pisum sativum Miill.

Phaseolus vulgaris Gray.

Apios tuber osa Gray.

Mitchella repens Gray.

Primula grandiflora, P. ojficinalis . Lubbock.

Ly thrum Salicaria Gray.

VII

Asclepias Cornuti ,

VIII

Cypripedium acaule

. . Miill., Newell.

Newell.

439. Cleistogamous Flowers. — In marked contrast with
such flowers as those discussed in the preceding sections,
which bid for insect visitors or expose their pollen to be
blown about by the wind, are certain flowers which remain
closed even during the pollination of the stigma. These
flowers are called cleistogamous and of course are not

370

FOUNDATIONS OF BOTANY

cross-pollinated. Usually they occur on plants which
also bear flowers adapted for cross-pollination, and in this

FIG. 261. — A Violet, with Cleistogamous Flowers.

The objects which look like flower-buds are cleistogamous flowers in various
stages of development. The pods are the fruit of similar flowers. The
plant is represented as it appears in late July or August, after the ordi-
nary flowers have disappeared.

ECOLOGY OF FLOWERS

371

case the closed flowers are much less conspicuous than
the others, yet they produce much seed. Every one
knows the ordinary flowers of the violet, but most people

FIG. 262. — Protection of Pollen from Moisture.

At the left herb Robert and sweet scabious in sunny weather ; at the right
the same flowers during rain.

do not know that violets very generally, after the blos-
soming season (of their showy flowers) is over, produce
many cleistogamous flowers, as shown in Fig. 261.

372 FOUNDATIONS OF BOTANY

440. Protection of Pollen from Rain. — Pollen is very
generally protected from being soaked and spoiled by rain
or dew either by the natural position of the flower prevent-
ing rain from entering, as in the case with most gamo-
petalous, nodding flowers, or by changes in the position
of the flower, and by its opening in sunny weather and
closing at night or during rain. Sometimes the flower
both changes its position and closes, as is the case with
the herb Robert and the sweet scabious (Fig. 262). The
adaptations of flowers to protect their pollen from becom-
ing wet can best be understood by actually examining the
same flower in sunshine and during rain.

PLATE XI. — Aster and Golden-Rod

CHAPTER XXIX
HOW PLANTS ARE SCATTERED AND PROPAGATED

441. Means of Propagation among Cryptogams. — Some
of the highest cryptogams, as the ferns, spread freely by
means of their creeping rootstocks, and the gardener who
wishes quickly to get large, strong ferns often finds it the
easiest plan to cut to pieces and reset the rootstocks of a
well-established plant. Some ferns also grow readily from
bulblets produced on the fronds. In the walking fern
the tip of the frond roots and begins a new plant. Most
flowerless plants, however, are reproduced either by a
process of fission, as in Pleurococcus (Sect. 278), Diatoms
(Sect. 271), Bacteria (Sect. 266), and many other groups,
or by some kind of spore (Sect. 259). The spore is
usually so small an object that it is carried with the great-
est ease by currents of water or of air, as the case may
be, so that it is no sooner liberated than it is swept away,
often to a very distant locality, where it can grow and not
be interfered with by too many neighbors of its own kind.
Thus spores of any of the marine algse are certainly carried
thousands of miles by ocean currents, and spores of tree
ferns may be blown great distances from one oceanic island
to another, or the spore contents of a puff-ball might travel
on the wind half the breadth of a continent.

442. Dispersal of Seed-Plants by Roots and Rootstocks.—
The student has learned (in Chapters IV and V) that
roots and underground stems of many kinds may serve to

373

374 FOUNDATIONS OF BOTANY

reproduce the plant. Either roots or rootstocks may travel
considerable distances horizontally in the course of their
growth and then shoot up and produce a new plant, which
later becomes independent of the parent. The sedges (Fig.
43) are excellent illustrations of this process, and trees

like the common
locust and the
silver-leaf poplar
become great nui-
sances in the neigh-
borhood of lawns

FIG. 263. — Plant of a Black

Raspberry, showing One and gardens by

in many places. When growing
wild, such trees as these depend largely upon spreading
by the roots to keep up their numbers.1

443, Dispersal of Seed-Plants by Branches. — There is a
shrub of the Honeysuckle Family,2 common in the northern
woods, which is quite generally known as hobble-bush, or
witch-hobble, and sometimes as trip-toe. This is because
the branches take root at the end and so form loops which
catch the foot of the passer-by. The same habit of growth
is found in the raspberry-bush (Fig. 263), in one species of
strawberry-bush (Euonymus), and some other shrubs. Many
herbs like the strawberry-plant and the cinquefoil send

1 See Beal's Seed Dispersal, Chapters II and in.

2 Viburnum lantanoides.

HOW PLANTS ARE SCATTERED

375

out long, leafless runners which root at intervals and so
propagate the plant, carrying the younger individuals off
to a considerable distance from the parent plant.

Living branches may drop freely from the tree and then
take root and grow, after having been blown or been car-
ried by a brook or river to a favorable spot, perhaps hun-
dreds of yards away. The so-called snap-willows lose
many live twigs under conditions suit-
able for starting new trees.

A slightly different mode of dis-
persal from that of
the raspberry is one
in which buds sepa-
rate from the plant
and serve to propa-
gate it. In the blad-
derwort (Fig. 264),
at the close of the
growing season, the
terminal buds are released by the decay of the stem and
sink to the bottom of the water in which the plants live,
there to remain dormant until spring. Then each bud
starts into life and gives rise to a new individual.

444. Dispersal of Seed-Plants by Bulblets. — Almost
every farmer's boy knows what "onion-sets" are. These
are little bulbs, produced at the top of a naked flower-
stalk or scape by some kinds of onions which do not
usually flower or bear seed. Tiger-lilies produce some-
what similar bulblets in the axils of the leaves, and there
is a large number of species, scattered among numerous
families of plants, all characterized by the habit of producing

FIG. 264. — A Free Branch and Two Buds of
Bladderwort.

376

FOUNDATIONS OF BOTANY

bulblets. When mature the bulblets fall off readily, and if
they find lodgment on unoccupied soil, they grow readily
into new plants. Sometimes they are carried moderate
distances by wind or water, and if the ground slopes, they
may easily roll far enough to get started in new places.

FIG. 265. — Fruit of Smoke-Tree (Rhus Cotinus).

Only one pedicel bears a fruit, all the others are sterile, branched , and covered
with plumy hairs.

445. Dispersal of Seeds. — Seeds are not infrequently
scattered by apparatus by which the plant throws them
about. More commonly, however, they depend upon
other agencies, such as wind, water, or animals, to carry
them. Sometimes the transportation of seeds is due to

HOW PLANTS ARE SCATTERED

377

the structure of the seeds themselves, sometimes to that
of the fruit in which they are enclosed ; the essential
point is to have transportation to a long distance made
as certain as possible, to avoid overcrowding.

446. Explosive Fruits. — Some dry fruits burst open
when ripe in such a way as to throw their seeds violently
about. Interesting

studies may be made,
in the proper season,
of the fruits of the
common blue violet,
the pansy, the wild
balsam, the garden
balsam, the crane's-
bill, the herb Robert,
the witch-hazel, the
Jersey tea, and some
other common plants.

The Capsule Of the FIG- 266. -Fruits of Linden, with a Bract joined
r < to the Peduncle and forming a Wing.

tropical American

sand-box tree bursts open when thoroughly dry with a noise

like that of a pistol shot.

447. Winged or Tufted Fruits and Seeds. — The fruits
of the ash, box-elder, elm, maple (Fig. 169), and many
other trees, are provided with an expanded membranous
wing. Some seeds, as those of the catalpa and the trumpet-
creeper, are similarly appendaged. The fruits of the
dandelion, the thistle (Fig. 267), the fleabane, and many
other plants of the group to which these belong, and the
seeds of the willow, the milkweed (Fig. 267), the willow-
herb, and other plants, bear a tuft of hairs.

378

FOUNDATIONS OF BOTANY

The student should be able, from his own observations on
the falling fruits of some of the trees and other plants above
mentioned, to answer such questions as the following :

What is the use of
the wing-like append-
ages? of the tufts of
hairs?

Which set of con-
trivances seems to be
the more successful of
the two in securing
this object?

What particular
plant of the ones avail-
able for study seems
to have attained this
object most perfectly ?

What is one reason
why many plants with
tufted fruits, such as
the thistle and the dan-
delion, are extremely
troublesome weeds?

A few simple experi-
ments, easily devised
by the student, may
help him to find an-
swers to the questions
above given.1

FIG. 267. — "Winged Fruits of Thistle ; Winged Seeds
of Milkweed.

448. Tumbleweeds. — Late in the autumn, fences, par-
ticularly on prairie farms that are not carefully tilled, often
serve as lodging-places for immense numbers of certain
dried-up plants known as tumbleweeds. These blow
about over the level surface until the first snow falls and

1 See Kerner and Oliver, Vol. II, pp. 833-875 ; also Seal's Seed Dispersal

HOW PLANTS ARE SCATTERED

379

even after that (Fig. 269), often traveling for many miles
before they come to a stop, and rattling out seeds as they
go. Some of the commonest tumbleweeds are the Russian
thistle (Fig. 268), the pigweed (Amarantus albus. Fig. 269),
the tickle-grass (Fig. 270), and a familiar pepper-grass
(Lepidium). In order to make a successful tumbleweed, a
plant must be pretty nearly globular in form when fully
grown and dried, must be tough and light, must break off
near the ground, and drop its seeds only a few at a time
as it travels. A single plant
of Russian thistle is some-
times as much as three feet
high and six feet in diameter
and carries not less than two
hundred thousand seeds.

449. Many -Seeded Pods
with Small Openings. —
There are many fruits which
act somewhat like pepper-
boxes. The capsule of the
poppy is a good instance of
this kind, and the fruit of
lily, monkshood (Fig. 168),
columbine, larkspur, and
jimson weed (Fig. 271) acts
in much the same way.
Clamping the dry peduncle
of any one of these ripe

£ ., i 1 T •, PIG. 268.— Russian Thistle.

fruits, so as to hold it up-
right above the table-top, and then swinging it back and
forth, will readily show its efficiency in seed dispersal.

380

FOUNDATIONS OF BOTANY

450, Study of Transportation by Water. — Nothing less
than a long series of observations by the pond-margin and
the brookside will suffice to show how general and impor-

FIG. 269. — Tumbleweeds 1 lodged against a Wire Fence in Winter.

tant is the work done by water in carrying the seeds of
aquatics. An experiment will, however, throw some light
on the subject.

EXPERIMENT XL

Adaptation for Transportation by Water. — Collect fruits of as
many aquatic, semi-aquatic, or riverside and brookside species of
plants as possible, place them on shallow pans of water and notice
what proportion of all the kinds studied will float. Leave them
twenty-four hours or more and see whether all the kinds that floated
at first are still afloat. Some desirable fruits for this experiment

1 Amarantus albus.

HOW PLANTS ARE SCATTERED

381

are : aquatic grasses, rushes and sedges, polygon urns, water-dock,
bur-reed, arrowhead, water-plantain, pickerel-weed, alder, button-
bush, water-parsnip (Sium), water-hemlock (Cicuta), water penny-
wort (Hydrocotyle).

451. Distances traversed by Floating Seeds. — Ocean
currents furnish transportation for the longest journeys
that are made by floating

seeds. It is a well-known
fact that cocoa-palms are
among the first plants to
'spring up on newly formed
coral islands. The nuts
from which these palms
grew may readily have
floated a thousand miles
or more without injury.
On examining a cocoanut
with the fibrous husk at-
tached, just as it fell from
the tree, it is easy to see -
how well this fruit is
adapted for transportation
by water. There are al-
together about a hundred
drifting fruits known, one
(the Maldive nut) reach-
ing a Weight of twenty to FIG. 270. — Panicle of Tickle-Grass, a
, r> T Common Tumbleweed.

twenty-five pounds.

452, Burs. — A large class of fruits is characterized by
the presence of hooks on the outer surface. These are
sometimes outgrowths from the ovary, sometimes from

382 FOUNDATIONS OF BOTANY

the calyx, sometimes from an involucre. Their office is
to attach the fruit to the hair or fur of passing animals.
Often, as in sticktights (Fig. 272), the hooks are compara-
tively weak, but in other cases, as in the cocklebur (Fig.
272), and still more in the Martynia, the fruit of which
in the green condition is much used for pickles, the
hooks are exceedingly strong. Cockleburs can hardly be
removed from the tails of horses and cattle, into which

i ii in

FIG. 271. — Three Fruits adapted for Dispersal by the Shaking Action of the Wind.
I, celandine ; II, pea ; III, jimson weed (Datura).

they have become matted, without cutting out all the
hairs to which they are fastened.

A curious case of distribution of this kind occurred
in the island of Ternate, in the Malay Archipelago. A
buffalo with his hair stuck full of the needle-like fruits of
a grass1 was sent as a present to the so-called King of
Ternate. Scattered from the hair of this single animal,
the grass soon spread over the whole island.

1 Andropogon acicularis.

HOW PLANTS AKE SCATTERED

383

Why do bur-bearing plants often carry their fruit until
late winter or early spring?

What reason can be given for the fact that the burdock,
the cocklebur, the beggar's-ticks, the hound's-tongue, and
many other common burs, are among the most persistent
of weeds ?

453, Uses of Stone Fruits and of Fleshy Fruits to the
Plant. — Besides the dry fruits, of which some of the
principal kinds have been mentioned, there are many kinds

FIG. 272. — Burs.

A, sticktights ; B, sticktights, two segments, magnified ;
C, burdock ; D, cockleburs.

of stone fruits and other fleshy fruits (Sects. 242-247).
Of these the great majority are eatable by man or some of
the lower animals, and oftentimes the amount of sugar
and other food material which they contain is very con-
siderable. It is a well-recognized principle of botany, and

384

FOUNDATIONS OF BOTANY

of zoology as well, that plants and animals do not make
unrewarded outlays for the benefit of other species. Evi-
dently the pulp of fruits is not to be consumed or used

FIG. 273. — Barbs and Hooks of Burs.

I, barbed points from fruit of beggar 's-ticks, magnified eleven times ;
• II, hook of cocklebur, magnified eleven times ; III, beggar's-ticks
fruit, natural size ; IV, cocklebur hook, natural size.

as food by the plant itself or (in general) by its seeds. It
is worth while, therefore, for the student to ask himself
some such questions as these : 1

(1) Why is the pulp of so many fruits eatable ?

(2) Why are the seeds of many pulpy fruits bitter or
otherwise unpleasantly flavored, as in the orange ?

(3) Why are the seeds or the layers surrounding the

1 See Kerner and Oliver's Natural History of Plants, Vol. II, pp. 442-450.

HOW PLANTS ARE SCATTERED

385

seeds of many pulpy fruits too hard to be chewed, or
digested, as in the date and the peach?

(4) Why are the seeds of some pulpy fruits too small
to be easily chewed, and also indigestible, as in the fig
and the currant?

(5) Account for the not infrequent presence of currant
bushes or asparagus plants in such localities as the forks
of large trees, sometimes at a height of twenty, thirty, or
more feet above the ground (Fig. 274).

Careful observation of the neighborhood of peach, plum,
cherry, or apple trees at the season when the fruit is ripe
and again during the following spring, and an examina-
tion into the distribution of wild
apple or pear trees in pastures
where they occur, will help the
student who can make such ob-
servations to answer the preced-
ing questions. So, too, would
an examination of the habits of
fruit-eating quadrupeds and of
the crop and gizzard of fruit-
eating birds during the season
when the fruits upon which they
feed are ripe.

454. Seed-Carrying purposely
done by Animals. — In the cases
referred to in the preceding sec-
tions, animals have been seen
to act as unconscious or even unwilling seed-carriers.
Sometimes, however, they carry off seeds with the plan
of storing them for food. Ants drag away with them to

FIG. 274. — Red Rasp-
berry Bush, in Fork
of a Maple.

386

FOUNDATIONS OF BOTANY

their nests certain seeds which have fleshy growths on
their outer surfaces. Afterwards they eat these fleshy

FIG. 275. — Red Cedar Trees planted by Birds roosting on Fences.

parts at their leisure, leaving the seed perfectly fit to
grow, as it often does.1

Squirrels and bluejays are known to carry nuts and
acorns about and bury them for future use. These

FIG. 276. — Seed of Bloodroot with Caruncle or Crest, which serves as a Handle
for Ants to hold on to. Ant ready to take the seed.

deposits are often forgotten and so get a chance to grow,
and in this way a good deal of tree-planting is done.

1 See Beal's Seed Dispersal, pp. (39, 70.

CHAPTER XXX

THE STRUGGLE FOR EXISTENCE AND THE SURVIVAL
OF THE FITTEST1

455. Weeds. — Any flowering plant which is trouble-
some to the farmer or gardener is commonly known as a
weed. Though such plants are so annoying from their
tendency to crowd out others useful to man, they are of
extreme interest to the botanist on account of this very
hardiness. The principal characteristics of the most suc-
cessful weeds are their ability to live in a variety of soils
and exposures, their rapid growth, resistance to frost,
drought, and dust, their unfitness for the food of most of
the larger animals, in many cases their capacity to accom-
plish self-pollination, in default of cross-pollination, and
their ability to produce many seeds and to secure their
wide dispersal. Not every weed combines all of these
characteristics. For instance, the velvet-leaf or butter-
print,2 common in cornfields, is very easily destroyed by
frost ; the pigweed and purslane are greedily eaten by pigs,
and the ragweed by some horses. The horse-radish does
not usually produce any seeds.

It is a curious fact that many plants which have finally
proved to be noxious weeds have been purposely intro-
duced into the country. The fuller's teasel, melilot,
horse-radish, wild carrot, wild parsnip, tansy, oxeye daisy,

1 See Darwin's Origin of Species, Chapters III and IV.

2 Abutilon Avicennse.

387

388 FOUNDATIONS OF BOTANY

and field-garlic are only a few of the many examples of
very troublesome weeds which were at first planted for
use or for ornament.

456. Study of Weeds. — Select two or more out of the
following list of weeds and report on the qualities which
make them troublesome from the farmer's point of view
(successful from their own).1

LIST OF WEEDS2

1. Barn-grass,* Panicum Crus-galli.

2. Beggar's lice,* Cynoglossum officinale.

3. Beggar's-ticks, Bidens frondosa.

4. Black mustard,* Brassica nigra.

5. Blue thistle,* Echium vulgare.

6. Buffalo bur, Solarium rostratum.

7. Burdock,* Arctium Lappa.

8. Buttercup,* Ranunculus bulbosus.

9. Butterweed,* Erigeron canadensis.

10. Carpet weed, Mollugo verticillata.

11. Charlock,* Brassica Sinapistrum.

12. Chess or cheat,* Bromus secalinus.

13. Chickweed, Stellaria media. »

14. Chicory,* Cichorium Intybus.

15. Clover dodder,* Cuscuta Trifolii.

16. Cocklebur,* XantJiium spinosum.

17. Corn cockle,* Agrostemma Giihago.

1 This study will be of little value in city schools, since the plants should
be examined as they grow. Specimens of the mature weed and of its fruits
and seeds may be preserved by the teacher from one season to another for
class use. Whole specimens of small plants, such as purslane, may be put
into preservative fluid (see Handbook). Ordinary weeds, such as ragweed,
pigweed, etc., may be pressed and kept as roughly prepared herbarium
specimens, while such very large plants as jimson weed, dock, etc., may be
hung up by the roots and thus dried.

2 Names marked in the list thus * are those of plants introduced from
other countries, mostly from Europe.

THE STRUGGLE FOR EXISTENCE 389

18. Cow herb,* Saponaria Vaccaria.

19. Daisy, oxeye,* Chrysanthemum Leucanthemum.

20. Dandelion,* Taraxacum ojficinale.

21. Dock, Rumex crispus.

22. Dog fennel,* Anthemis cotula.

23. Fox-tail grass,* Setaria glauca.
24.- Horse-nettle, Solarium carolinense.

25. Jamestown weed or Jimson weed,* Datura Stramonium

or D. Tatula.

26. Johnson grass, Andropogon halepensis.

27. Mallow,* Malva rotundifolia.

28. Milkweed, Asclepias Cornuti.

29. Nettle, Urtica gracilis.

30. Pigweed,* Amarantus retrojlexus.

31. Pigweed,* Chenopodium album.

32. Plantain,* Plantago major.

33. Pokeberry, Phytolacca decandra.

34. Purslane, Portulaca oleracea.

35. Quick-grass,* Witchgrass, Agropyrum repens.

36. Ragweed, Ambrosia artemisicefolia.

37. Rib grass,* Plantago lanceolata.

38. Sand bur, Cenchrus tribuloides.

39. Shepherd's purse,* Capsella Bursa-pastoris.

40. Smartweed, Polygonum Hydropiper.

41. Sorrel,* Rumex Acetosella.

42. Spanish needles, Bidens bipinnata.

43. Sticktights, Desmodium canadense.

44. Thistle,* Cirsium lanceolatum, C. arvense.

45. Yarrow, Achillea Millefolium.

457. Origin of Weeds.1 — By far the larger proportion
of our weeds are not native to this country. Some have
been brought from South America and from Asia, but
most of the introduced kinds come from Europe. The
importation of various kinds of grain and of garden-seeds,

1 See the article " Pertinacity and Predominance of Weeds," in Scientific
Papers of Asa Gray, selected by C. S. Sargent, Vol. II, pp. 234-242.

390 FOUNDATIONS OF BOTANY

mixed with seeds of European weeds, will account for the
presence of many of the latter among us. Others have
been brought over in the ballast of vessels. Once landed,
European weeds have succeeded in establishing themselves
in so many cases, because they were superior in vitality
and in their power of reproduction to our native plants.
This may not improbably be due to the fact that the Euro-
pean and western Asiatic vegetation, much of it consisting
from very early times of plants growing in comparatively
treeless plains, has for ages been habituated to nourish in
cultivated ground and to contend with the crops which
are tilled there.

458. Plant Life maintained under Difficulties. — Plants
usually have to encounter many obstacles even to their
bare existence. For every plant which succeeds in reach-
ing maturity and producing a crop of spores or of seeds
there are hundreds or thousands of failures, as it is easy
to show by calculation. The morning-glory (Ipomoea pur-
pur ed) is only a moderately prolific plant, producing, in
an ordinary soil, somewhat more than three thousand
seeds.1 If all these seeds were planted and grew, there
would be three thousand plants the second summer, sprung
from the single parent plant. Suppose each of these
plants to bear as the parent did, and so on. Then there
would be :

9,000,000 plants the third year.
27,000,000,000 plants the fourth year.
81,000,000,000,000 plants the fifth year.
243,000,000,000,000,000 plants the sixth year.
729,000,000,000,000,000,000 plants the seventh year.

1 Rather more than three thousand two hundred by actual count and
estimation.

THE STRUGGLE FOR EXISTENCE 391

It is not difficult to see that the offspring of a single
morning-glory plant would, at this rate, soon actually
cover the entire surface of the earth. The fact that
morning-glories do not occupy any larger amount of ter-
ritory than they do must therefore depend upon the fact
that the immense majority of their seeds are not allowed
to grow into mature plants.

There are many plants which would yield far more sur-
prising results in a calculation similar to that just given
than are afforded by the morning-glory. For instance, a
foxglove capsule contains on an average nearly 1800
seeds. A small foxglove plant bears from 140 to 200 cap-
sules and a large one from 530 to 700. Therefore a single
plant may produce over 1,250,000 seeds. A single orchid
plant1 has been shown to produce over 10,000,000 seeds.

459. Importance of Dispersal of Seeds. — It is clear that
any means of securing the wide distribution of seeds is of
vital importance in continuing and increasing the numbers
of any kind of plant, since in this way destruction by over-
crowding and starvation will be lessened.

A few of the means of transportation of seeds have been
described in Sects. 445-454,, but the cases are so numerous
and varied that a special treatise might well be devoted to
this subject alone.

460. Destruction of Plants by Unfavorable Climates. —
Land-plants, throughout the greater part of the earth's
surface, are killed in enormous numbers by excessive heat
and drought, by floods, or by frost. After a very dry
spring or summer the scantiness of the crops, before the
era of railroads which nowadays enable food to be brought

1 Maxillaria, see Darwin's Fertilization of Orchids, Chapter IX.

392 FOUNDATIONS OF BOTANY

in rapidly from other regions, often produced actual fam-
ine. Wild plants are not observed so carefully as culti-
vated ones are, but almost every one has noticed the
patches of grass, apparently dead, in pastures and the
withered herbaceous plants everywhere through the fields
and woods after a long drought.

Floods destroy the plants over large areas, by drowning
them, by sweeping them bodily away, or by covering them
with sand and gravel.

Frosts kill many annual plants before they have ripened
their seeds, and severe and changeable winters sometimes
kill perennial plants.

461. Destruction by Other Plants Overcrowding is

one of the commonest ways in which plants get rid of
their weaker neighbors. If the market-gardener sows his
lettuce or his beets too thickly, few perfect plants will be
produced, and the same kind of effect is brought about in
nature on an immense scale. Sometimes plants are over-
shadowed and stunted or killed by the growth all about
them of others of the same kind ; sometimes it is plants
of other kinds that crowd less hardy ones out of existence.

Whole tribes of parasitic plants, some comparatively
large, like the dodder and the mistletoe, others micro-
scopic, like blights and mildews, prey during their whole
lives upon other plants.

462, Adaptations to meet Adverse Conditions. — Since
there are so many kinds of difficulties to be met before the
seed can grow into a mature plant and produce seed in its
turn, and since the earth's surface offers such extreme
variations as regards heat, sunlight, rainfall, and quality
of soil, it is evident that there is a great opportunity

THE STRUGGLE FOR EXISTENCE 393

offered for competition among plants. Of several plants
of the same kind, growing side by side, where there is
room for but one full-grown one, all may be stunted, or
one may develop more rapidly than the others, starve them
out, and shade them to death. Of two plants of different
kinds the hardier will crowd out the less hardy, as ragweed,
pigweed, and purslane do with ordinary garden crops.
Weeds like these are rapid growers, stand drought or
shade well, will bear to be trampled on, and, in general,
show remarkable toughness of organization.

Plants which can live under conditions that would be
fatal to most others will find much less competition than
the rank and file of plants are forced to encounter. Lichens,
growing on barren rocks, are thus situated, and so are the
fresh-water plants, somewhat like pond-scum in their struc-
ture, which are found growing in hot springs at tempera-
tures of 140°, or in some cases nearly up to 200°.

463, Examples of Rapid Increase. — Nothing but the
opposition which plants encounter from overcrowding or
from the attacks of their enemies prevents any hardy kind
of plant from covering all suitable portions of a whole
continent, to the exclusion of most other vegetable life.
New Zealand and the pampas of La Plata and Paraguay,
in South America, have, during the present century, fur-
nished wonderful examples of the spread of European
species of plants over hundreds of thousands of square
miles of territory. The newcomers were more vigorous,
or in some way better adapted to get on in the world
than the native plants which they encountered, and so
managed to crowd multitudes of the latter out of
existence.

394 FOUNDATIONS OF BOTANY

In our own country a noteworthy case of the kind has
occurred so very recently that it is of especial interest
to American botanists. The so-called Russian thistle
(Fig. 268), which is merely a variety of the saltwort, so
common along the Atlantic coast, was first introduced into
South Dakota in flaxseed brought from Russia and planted
in 1873 or 1874. In twenty years from that time the plant
had become one of the most formidable weeds known, over
an area of about twenty-five thousand square miles.

464. Importance of Adaptiveness in Plants. — It may be
inferred from the preceding sections that a premium is set
on all changes in structure or habits which may enable
plants to resist their living enemies or to live amid partially
adverse surroundings of soil or climate. It would take a
volume to state, even in a very simple way, the conclusions
which naturalists have drawn from this fact of a savage
competition going on among living things, and it will be
enough to say here that the existing kinds of plants to a
great degree owe their structure and habits to the operation
of the struggle for existence, this term including the effort to
respond to changes in the conditions by which they are sur-
rounded. How the struggle for existence has brought
about such far-reaching results will be briefly indicated in
the next section.

465. Survival of the Fittest. — When frost, drought,
blights, or other agencies kill most of the plants in any
portion of the country, it is often the case that many of
the plants which escape do so because they can stand more
hardship than the ones which die. In this way delicate
individuals are weeded out and those which are more
robust survive. But other qualities besides mere toughness

THE STRUGGLE FOR EXISTENCE 395

often decide which plant or plants of any particular
kind shall live and which ones shall die out. In every
grove of oaks there are some with sweeter and others with
more bitter acorns. One shellbark hickory bears nuts
whose shell is easily cracked by hogs, while another pro-
tects its seeds by a shell so hard that it is cracked only
by a pretty heavy blow. In case of all such differences,
there is a strong tendency to have the less eatable fruit or
seed preserved and allowed to grow, while the more eat-
able varieties will be destroyed. Some individuals of the
European holly produce bright red berries, while others
produce comparatively inconspicuous yellow ones. It has
been found that the red berries are much more promptly
carried off by birds, and the seeds therefore much more
widely distributed than the yellow ones are. The result
of this kind of advantage, in any of its countless forms, is
sometimes called survival of the fittest, and sometimes
natural selection. The latter name means only that the
outcome of the process just described, as it goes on in
nature, is much the same as that of the gardener's selection,
when, by picking out year by year the earliest ripening
peas or certain kinds of the oddest-colored chrysanthe-
mums, he obtains permanent new varieties. Natural
agencies, acting on an enormous scale through many
ages, may well be supposed to have brought about the
perpetuation of millions of such variations as are known
to be of constant occurrence among plants, wild as well
as cultivated.

INDEX

Starred page-numbers indicate where cuts occur.

PARTS I AND II

Absorption of carbon dioxide, 166-
170.

Acacia, leaf of, *145.

Accessory buds, 122, *123.

Accessory fruits, *226.

Acuminate, *131.

Acute, *131.

Adaptations to conditions of exist-
ence, 394.

Adherent, 204.

Adnate, 204.

Adventitious buds, 128.

Adventitious roots, 36.

Aerial roots, 36, *37, *38, *39.

Agaricus, study of, 264-266*.

Age of trees, 71.

Aggregate fruits, 225, *226.

Ailanthus twig, *121.

Air, relation to germination, 10-
12.

Air chamber, *151, *153, *154.

Air-passages in Hippurisstem,*173.

Akene, *222.

Albuminous substances, 22.

Algae, 232, 241-257*.

Algae, classification of, *257.

Algae, study of, 241-257*

Alternate, *65, 66.

Alternate leaves, *140.

Alternation of generations, 278.

Althaea leaf, *152.

Anatomy of plants (see under root,

stem, leaf, flower, fruit, structure

of).

Angiosperms, 233.
Angiosperms, oldest, 304, 305.
Animal food, need of, 344.
Animals, defenses against, 345-

352*

Annual growth, indefinite, 69.
Annual ring, *100, *101.
Annuals, 71.
Anther, 201, 202, *203.
Anther, modes of opening, *211.
Antheridia, *284, 285.
Antherozoids, 247, 248, *251, 254,

*279, *284.
Antipodal cells, *215.
Ant-plants, 346, *347.
Ants plant seeds, *386.
Apetalous, *198.
Apothecia, 271.
Apple leaf, stipules of, *135.
Aquatic roots, 37.

397

398

FOUNDATIONS OF BOTANY

Arch of hypocotyl, 25-27.
Archegonia, *284, 285, *295.
Arctic willow, *328.
Aristolochia stem, bundle of, *88.
Aristolochia stem, cross-section of,

*87, 88.

Arrangement of leaves, *140, *141 .
Arrow-shaped, *132.
Asci, 263, 270, 273.
Ascomycetes, 232.
Asexual generation, 278.
Ash tree, naturally grafted, *99.
Asparagus, 79, *80.
Aspidium, *288.
Asplenium, study of, 286-289*.
Assimilation, 171, 172.
Autumn leaves, coloration of, 176.
Axillary bud, *122.
Axillary flowers, *186.

Bacillariales, 232.

Bacilli, *237.

Bacteria, 232, *237.

Bacteria, manufacture of nitric acid

by, 340.

Bacteria, study of, 238, 239.
Barbed hairs, *351.
Barberry, spiny leaves of, *348.
Bark, 86, *91, 104.
Basidia, *266.
Basidiomycetes, 232.
Bast, *87, *91, *92.
Bast-bundle, *92.
Bean-pod, study of, 219.
Bean seed, 7, 8.
Beech twig, 64.

Beech-wood, cross-section of, *101.
Bees, 355, *356, *360.
Beet leaf, *151.
Beggar's ticks, *384.
Begonia leaf, osmose in, 51.

Bell-shaped, *202.

Belt's bodies, *347.

Berry, *225.

Berry, study of, 217.

Biennial, 47, 71.

Biogenesis, law of, 299, 300.

Birch, branching of, *71.

Bird-pollinated flowers, 362.

Birds plant seeds, 385, *386.

Black mould, study of, 257, 258,

259.

Bladder-wrack, *250.
Botanical geography, 324-335.
Botanical geography of United

States, 333-335.
Botany, definition of, 1.
Box-elder, buds of, *123.
Box-elder, radial and cross-sections

of stem of, *89.
Bract, *186, 187.
Branches formed from adventitious

buds, 128.

Branching, alternate, *65, 66.
Branching and leaf-arrangement,

64, 65.

Branching, opposite, *65.
Branch-spine, *69.
Brazil nut, food stored in, 23, 24.
Breathing-pore, *153.
Bryophytes, 232, 277, 278.
Buckeye, bud of, *120.
Bud, horse-chestnut, 119, 120.
Bud-scales, 121.
Buds, 118-129.
Buds, adventitious, 128.
Buds, dormant, 127, 128.
Buds, naked, 121.
Buds, position of, 121, *122, *123,

*124.

Buds, structure of, 119, *125.
Bulb, 77, *79.

INDEX

399

Bulb, hyacinth, *79.

Bulb, onion, 77.

Bulblets, 375, 376.

Bulrush, cross-section of stem of,

*84.

Burs, 381, 382, *383.
Buttercup, leaf of, *135.
Buttercup, study of flower of, 195.

196.
Butternut, buds of, *124.

Cabbage, a bud, 123.

Cactus, *80, *315.

Cactus flower, transitions in, *208.

Caladium, 76, *77.

Calyx, *197.

Cambium, *87, *88, *89, 95-100.

Cambium-ring, 96, *97.

Canna, parallel veining in, 136.

Capsule, 223.

Carbon dioxide, absorption of, 166-

168.
Carbon dioxide, disposition of, 168,

169.

Carnivorous plants, 342-344*.
Carpel, 198.

Castor bean, germination of, *7.
Castor-oil plant, early history of

stem, *95.
Castor-oil plant, nbro-vascular

bundle of, *95.
Catharinea, *282.
Catkin, *187.
Celandine, leaf of, *134.
Cell, 20, 21.
Cell-contents, *19, *155, 180, *183,

*184.

Cell-contents, continuity of, 146.
Cell-division, *183, *242, 245.
Cell-multiplication in pond-scum,

*242.

Cell-sap, *183.

Cell, simplest form of, 178, *179,

180.

Cell-wall, 178.
Cells, isolated wood-, *91.
Cellulose, a compound of carbon,

hydrogen, and oxygen ; the chief

constituent of ordinary cell- walls,

156, 171, 268.
Central cylinder, *42.
Central placenta, *205.
Chara, *248, *249.
Characese, 249, 250.
Chemical changes in leaves before

falling, 175, 176.
Cherry, buds in axils of leaves,

*122.

Cherry twig, *63, *125.
Chestnut fruit, *222.
Chlorophyceae, 232.
Chlorophyll, 168, 169, 176.
Chlorophyll bodies, *154, *155.
Cilium, 180. .
Circulation of protoplasm, *184,

185.

Cladophyll, 79, *81.
Class, 231.

Classification, 228-234.
Cleistogamous flowers, 369, *370.
Clerodendron, *363.
Climbing plants, 73-75*.
Climbing shrubs, stem-structure,

99, 100.

Climbing stems, *73, *74, *75.
Clinostat, *58, 59.
Clover leaf, *144.
Club-moss, study of, 291, *292.
Cluster-cup, 259, *261.
Coherent, 200.
Cohesion, 204, *205.
Collenchyma, *95.

400

FOUNDATIONS OF BOTANY

Colocasia, *77.

Coloration of autumn leaves, 176.
Colors of flowers, 357, 358.
Common receptacle, *189.
Compass-plant, nearly vertical

leaves of, *147.
Composite head, 188, *189, 190.
Compound cyme, *191.
Compound leaves, *137, *138, 139.
Compound pistil, 202.
Compound umbel, *189.
Conceptacles, 250, *252.
Condensed stems, 78.
Conifers, wood of, *93, *94.
Coniferous wood, structure of, 92,

*93, *94.
Conjugate, 232.
Conjugating cell, *243, *259.
Conjugation, *243.
Consolidated, 204.
Continuity of protoplasm, 146.
Contractile vacuole, 180.
Contractility, 182.
Cork, 90, *100, 104, 115.
Corm, a bulb-like, fleshy stem, or

base of stem, " a solid bulb."
Corn, aerial roots of, *38.
Corn, cross-section of stem of, *83.
Corn, germination of, 8.
Corn, grain of, *16.^~
Corn, root- tip, section, *42.
Corn-stem, structure of, *83, 84.
Corolla, *197.
Corymb, *186, 187.
Cotyledon, 7.
Cotyledon, disposition made of, 28,

29.

Cotyledons, thickened, use of, 29.
Crenate, 132.
Cross-pollination, 353.
Crow-berry, rolled-up leaf of, *317.

Cryptogams, 231.

Cryptogams, classes of, 232, 233.

Cuspidate, *131.

Cuticle, unequal development of, by

epidermis-cells, 156, *157.
Cutin, 156.
Cutting leaves, *351.
Cyme, *191.
Cypress, 71.

Dahlia, thickened roots of, *41.
Daily movements of leaves, *144,

*145, *146.
Dandelion, *72.
Darwin, Charles, 353.
Date-palms, *85.
Datura, stigma of, *213.
Deciduous, 175.

Defenses against animals, 345-352.*
Definite annual growth, 69.
Dehiscent fruits, 222, *223.
Deliquescent trunk, 66, *67.
Dentate, 132.

Descent of water, 109, *110.
Desert, Sahara, *325.
Desmids, *243.

Destruction of plants, 391, 392.
Determinate inflorescence, 191.
Deutzia leaves, *142, *143.
Diadelphous, 202.
Diagrams, floral, 204, *205, *296.
Diatoms, study of, *240, 241.
Dichogamy, *363, *364.
Dicotyledonous plants, 34, 233.
Dicotyledonous stem, annual, gross

structure of, 86, *87.
Dicotyledonous stem, cross-section

of, *87, *89, *91, *96, *100.
Dicotyledonous stem, mechanical

importance of distribution of

material in, 89, 90.

INDEX

401

Dicotyledonous stem, minute struc-
ture of, 86-98*.

Dicotyledonous stem, rise of water
in, 107, 108, *109.

Dimorphous flowers, *366, 367.

Dioecious, 200.

Discharge of pollen, *211.

Disk-flowers, 188, *189.

Dispersal of seeds, 376-386*.

Dispersal of seed-plants, 373-376.

Distinct, 201.

Distribution of material in mono-
cotyledonous stems, *84, 85.

Dock fruit, study of, 219, 220.

Dodder, 39, *40, 41.

Dormant buds, 127, 128.

Double flowers, 209.

Drip-leaves, *314.

Drosera, *341, *342, 343.

Drought, endurance of, 162, 163.

Drought-plants, 313-317*.

Dry fruits, 224.

Duckweed, 314.

Duct, *92.

Earliest plants, 298.

Ecology, 2, 307.

Egg, osmosis in, 50, *51.

Egg-cell, *249, *251, 280, *284, 285.

Elaters, 294.

Elliptical, *131.

Elm, *67.

Elm bud, *125.

Elm fruit, *223.

Elm leaf, 130, 133.

Elm, twig of, *125.

Emarginate, *131.

Embryo, 6, 17.

Embryo sac, *215.

Endosperm, *15, *16, 17, 19.

Energy, source of, in plants, 173.

Enslaved plants, 338, *339.
Epidermis, uses of, 156, *157.
Epidermis of root, *42, *44.
Epigynous, 204, *205.
Epipetalous, 204, *205.
Epiphytes, 322, *323.
Equisetales, 232.
Equisetum, study of, 292-295*.
Essential organs, *197.
Euphorbia splendens, *350.
Evergreen, 175.
Evolutionary history of plants,

298-305.

Excretion of water, 172, 173.
Excurrent trunk, *66.
Existence, struggle for, 387-393.
Exogenous, 96.
Explosive fruits, 377.

Fall of horse-chestnut leaf, *137.
Fall of the leaf, 175, 176.
Family, 230.

Family, subdivisions of, 231.
Fascicled roots, *41.
Fermentation, 269.
Fern, study of, 286-289*.
Fern-plants, 295-297.
Ferns, 290, 291.
Fertilization, *214, *215, 216.
Fibrous roots, *41.
Fibro-vascular bundles, *83.
Ficus elastica, leaf of, *154.
Ficus religiosa, drip-leaf of, *314.
Fig, transpiration in, 160, *161,

162.

Filament, 201, 202, *203.
Filicales, 232.
Fir wood, *93.
Fission, *242.
Fission-plants, 232.
Fittest, survival of, 394, 395.

402

FOUNDATIONS OF BOTANY

Flax, cross-section of stem of, *91.

Fleshy fruits, 224.

Fleshy fruits, uses of, 383-385.

Fleshy roots, 45, 40, *47.

Floating seeds, 381.

Floral diagrams, 204, *205, *206.

Floral envelopes, 198.

Floral organs, movements of, 365,

366.

Florideae, 255.

Flower, nature of, 208-211*.
Flower, organs of, *197.
Flower, plan of, 197-206*.
Flower-buds, position of, 186.
Flowerless plants, 232, 233, 235-

297.

Flowers, bird-pollinated, 362.
Flowers, colors of, 357, 358.
Flowers, ecology of, 353-372*.
Flowers, odors of, 357.
Flytrap, Venus, *343, 344.
Follicle, *223.
Food in embryo, 14.
Food, storage of, in root, 46, *47.
Food, storage of, in stem, 113-117.
Food, storage outside of embryo,

15.

Formative tissue, 95.
Fossil plants, 298, 299.
Fossils, 298.
Four-o'clock seed, 15.
Foxglove, pinnate leaf of, *133.
Free, 204.

Free central placentation, *205.
Frond, 287, *288.
Frost, action of, 394.
Fruit, 221-227*.
Fruit, definition of, 221.
Fruit-dots, *288.
Fruits, study of, 217-220.
Fruits, uses of, 376-386*.

Fucus, 250-252*.
Funaria, *284.
Fungi, 232, 274-276.

Gametophyte, 291.

Gamopetalous, 200.

Gamosepalous, 200.

Gemmae, 279.

Generations, alternation of, 278.

Generative cells, in pollen tube,

*214.

Genus, 229.

Geography, botanical, 324-335.
Geography, botanical, of the United

States, 333-335.
Geotropism, *57, *58, 59, 68.
Germination, 5-13.
Germination, chemical changes

during, 11-13.

Germination, conditions of, 8-11.
GUIs, *264, 265.
Gonidia, 273.
Gourd-fruit, 224.
Grafting, 98, *99.
Grain, 222.

Grape sugar, test for, 116, 117.
Gray, Asa, 71.
Green layer of bark, 86, *91.
Groups, 231.
Growing point, *42.
Growth, measurement of, in stem,

32.

Growth, secondary, *96, *97, *100.
Guard-cells, *151, *153, *154, 158,

159.
Gymnosperms, 233.

Haematococcus, *244.
Hairs, 158.

Hairs, stinging, 349, 350, *351.
Halberd-shaped, *132.

INDEX

403

Half-parasites, 336.

Halophytes, 311, *319, 320, *326.

Hard bast, *87, *91, *92.

Haustoria, 39.

Head, *188.

Heart-shaped, *132.

Heartwood, 105.

Heliotropism, 148.

Hemlock, lateral extension of
roots, *60.

Hepaticse, 232, 280, 281.

Hepaticse, study of, 278-280*.

Herbs, 70.

Hesperidium, *225.

High mallow, provisions for cross-
pollination of, *364.

Hilum, 6.

Honey-bee, leg of, *356.

Honey-gland, *357.

Honey locust, spine, *69.

Hop, twining of, *75.

Hormogonia, *238.

Horse-chestnut bud, study of, 119,
120.

Horse-chestnut, germination, 8.

Horse-chestnut twig, 62-64.

Host, 39.

Hot springs, plants in, 393.

Hyacinth, bulb of, *79.

Hybrid, 229.

Hybridization, 229.

Hydrangea, transpiration in, 159-
161*

Hydrogen, 168.

Hydrophytes, 311, *312, *313,
*314.

Hymenium, *265.

Hyphae, 257, *258.

Hypocotyl, 6, 25-27.

Hypocotyl, cross-section of, 95.

Hypogynous, 204, *205.

Iceland moss, 274.
Imperfect flowers, 199.
Indefinite annual growth, 69.
Indehiscent fruits, 221, *222.
Indeterminate inflorescence, 186.
Indian corn, germination of, 8.
Indian corn, kernel of, 16.
Indian corn, root-tip, *42, ^3.
Indian corn, structure of stem,

*83, 84.

Indian pipe, 169.
India-rubber plant, leaf of, *154.
India-rubber plant, transpiration

of, 160-162.
Indusium, 287, *288.
Inflorescence, 186-191*.
Inflorescence, determinate, 191.
Inflorescence, diagrams of, *190.
Inflorescence, indeterminate, 186.
Insectivorous plants, 340-344*.
Insect pollination, 355-369*
Insect pollination, study of, 367-

369.
Insects, pollen-carrying apparatus

of, 355, *356.

Insects, sense of smell of, 357.
Insects, vision of, 358.
Insect-traps, leaves as, *342, *343.
Insect visits, 358-362*, *365.
Insertion of floral organs, *205.
Intercellular spaces, *95.
Internode, 32, 83.
Involucre, 188, *189.
Ipomcea Jalapa, 46.
Ipomcea, rate of increase of, 390,

391.

Iris, rootstock of, *77.
Irish moss, 253.
Irritability in plants, nature and

occurrence of, 182-184.
Ivy, aerial roots of, *39.

404

FOUNDATIONS OF BOTANY

Keel, *199.
Kidney-shaped, *131.
Knots, *102.

Labiate, *203.

Ladyfern, 286.

Lanceolate, *131.

Lateral buds, 63, 121.

Leaf, 130-139*.

Leaf, accumulation of mineral
matter in, 165.

Leaf-arrangement, *140,*141, *142,
*143.

Leaf-bases, *132.

Leaf-buds, 122, 123.

Leaf, fall of, 175, 176.

Leaf-like stems, 78, 79, *81.

Leaf-margins, *132.

Leaf-mosaics, 142, *143.

Leaf-outlines, *131.

Leaf-sections, *151, *154.

Leaf-spine, *348.

Leaf-stalk, 130.

Leaf-tendril, *138.

Leaf-tips, *131.

Leaf -traces, 155.

Leaves as insect-traps, *342, *343.

Leaves, compound, *137, *138, 139.

Leaves cutting, 350, *351.

Leaves, divided, 143.

Leaves, functions of, 155-174.

Leaves, movements of, *144, *145,
*146.

Leaves, simple, 137.

Leaves, structure of, 150-158*.

Legume, 223.

Lemon, study of, 217, 218.

Lenticels, 104.

Leucoium, pollen tube with gener-
ative cells, *214.

Lianas, *73.

Lichen, 232.

Lichenes, 232.

Lichens, nature of, 273, 274.

Lichens, study of, 270-273*.

Light, exposure to, 140-149*.

Light, movements towards, 148,

149.

Lignin, 171, 172.
Lily leaf, 150.
Lily, pollen grains producing tubes

on stigma, *214.
Limb of calyx or corolla, 200.
Lime, 165.

Linden, fruit cluster of, *377.
Linden fruit, *377.
Linden wood, structure of, *100.
Linear, *131.
Liverworts, 277-281*.
Living parts of the stem, 104, 105.
Lobe, 201.
Locules, 203.
Locust, pinnately compound leaf

of, *138.

Locust, thorn-stipules of, 350.
Luffa, 86.
Lupine, white, 8.
Lycopodiales, 232.
Lycopodium, study of, 291, *292.

Macrospores, 291, *302.

Macrosporophyll, 302.

Magnolia, forking of, *70, *71.

Mahogany wood, structure of, *101.

Maldive nut, 381.

Mallows, pollination in, 364.

Malt, 13.

Maltose, 116.

Mangrove, *319.

Maple fruit, *223.

Maple leaf, 134.

Marchantia, study of, 278-281*.

INDEX

405

Marestail, air-passages of, *173.
Mechanics of monocotyledonous

steins, *84, 85.
Medullary ray, 45, *101.
Melon, palmately netted-veined

leaf of, *133.
Melon-cactus, 78, *80.
Messmates, 340.
Mesophytes, 317, 318.
Mesquite, root-system of, 48.
Metabolism, 165-176.
Metabolism, digestive, 172.
Micropyle, 6.

Microsphsera, study of, 263, 264.
Microspores, *302.
Microsporophyll, 302.
Midrib, *133.

Mildews, powdery, 263, *264.
Mimicry, 347, 348.
Mineral matter accumulated in the

leaf, 165.
Mistletoe, 337.
Modified leaves, 121.
Moisture-plants, 311-313.
Monadelphous, 202, *204.
Monocotyledonous plants, 34, 233.
Monocotyledonous stems, *83, *84,

*85, 86.
Monocotyledonous stems, growth

of, in thickness, 85, 86.
Monocotyledonous stems, rise of

water in, *110.
Monocotyledons, 233.
Moncecious, 200.
Monotropa, 169.
Morning-glory, rate of increase of,

390, 391.

Morphology, 1, 33.
Moss, study of, 281-285.
Mosses, 281-285*.
Moths, *361, 362.

Mould, black, study of, 257, 258,

259.
Movement of water in plants, 107,

*108, *109, *110, 111, 112, 113.
Movements of floral organs, *365,

*366.
Movements of leaves, *144, *145,

*146.

Movements toward light, 148.
Mucronate, *131.
Mulberry, *226.
Mullein, hairs from corolla of,

*361.

Multiple fruits, *226.
Multiple primary roots, 14.
Musci, 232.

Mushroom, study of, 264-266*.
Mutilated seedlings, growth of, 14.
Mycelium, 257, *258.
Mykorhiza, 342.
Myrsiphyllum, 79, *81.
Myxogasteres, 232.
Myxothallophytes, 232, 233.

Naked buds, 121.

Nasturtium leaves, starch in, *170.

Natural selection, 394, 395.

Nectar, 356.

Nectar-glands, 356.

Nectar-guides, 358.

Nectaries, 357.

Negundo, radial and cross-sections

of stem of, *89.

Nemalion, study of, 253, 254, *255.
Netted-veined, *133.
Nettle, stinging hair of, *184.
Nightshade, leaf of, *349.
Nitella, study of, 247-250.
Nitrogen, 171, 340.
Nocturnal position, *144, *145,
Node, 31, 32, 83.

406

FOUNDATIONS OF BOTANY

Nucleus, 178.

Nucleus of root-hair, *49.

Nut, *222, 223.

Nutrient substances, 168, 169, 171.

Nutrition of plants, 165-176.

Oak leaves, arrangement of, *140.

Oat, root-system of, 48.

Obovate, *131.

Obtuse, *131.

Odors of flowers, 357.

Offensive-smelling plants, 352.

Oil, 21, 22.

Oil, essential, 24.

Oil, extraction, 22.

Oil, testing seeds for, 21, 22.

Onion, bulb of, 77.

Onion leaf, section of, *79.

Onion, structure of, 116.

Onion, tests for food-materials in,

116, 117.
Oogonia, *251.
Oosphere, *249, *251, 280, *284,

285.

Oospore, 247, 249.
Opposite, *65, *140, *141, *142.
Orbicular, *131.
Orchid, aerial roots of an, *37.
Order, 230.

Organs, essential, *197.
Organs, vegetative, 30.
Oscillatoria, study of, 239, 240.
Osmosis, 50-54.
Osmosis in an egg, 50, *51.
Osmosis in root-hairs, 53, 54.
Ovary, 201, 202, *203, *205.
Ovate, *131.
Ovoid, egg-shaped.
Ovule, 202, *203.
Ovule, spruce, fertilized, *303.
Ovule, structure of, *215.

Oxalis leaf, development of, *127.
Oxidation, 11, 12.
Oxygen, 11, 12, 166, 167, 168.
Oxygen-making, 167, 168.

Palisade-cells, *151.

Palmate, *133.

Pampas region, 393.

Panicle, *189, 190.

Panicum, *381.

Pansy, leaf-like stipules of, *135.

Papilionaceous corolla, *199.

Papillae on stigma of a lily, *214.

Paraphyses, 251, *252.

Parasites, 39, 336-338.

Parasitic roots, 39, *40.

Parenchyma, 94.

Parietal placenta, 203, *205.

Parsnip root, study of, 45, 46.

Pea seed, 8.

Pea seedling, mutilated, 14.

Pea seedling on clinostat, 58.

Peat bogs, 327.

Peat moss, *327.

Pedicel, *186, 187.

Peduncle, *186, 187.

Peg of squash seedling, 27.

Pepo, 224.

Perennial, 47, 71.

Perfect, 198.

Perianth, *197.

Pericarp, 224.

Perigynous, 204, *205.

Perithecia, 263.

Permanganate test, 28.

Petal, 197.

Petiole, 130, 134.

Phseophycese, 232.

Phanerogams, 231, 233.

Phanerogams, classes of, 233.

Phosphorus, 165.

INDEX

407

Phycomycetes, 232.

Physcia, 270-273.

Physiology, vegetable, 1.

Pigeon-wheat moss, study of, 281-
285.

Pileus, *264, 265.

Pine, seedling, *33.

Pine wood, *94.

Pinnae, leaflets of a pinnately com-
pound leaf, 138.

Pinnate, *133.

Pinnules, *288.

Pistil, *197, 201, 202, *203.

Pistil, parts of, *203.

Pitcher-plant, *340.

Pith, *83, *87, *88, *89.

Placenta, 203, *206.

Plankton, 333.

Plant colonies, 310.

Plant formations, 310.

Plant physiology, definition of, 1.

Plant societies, 307-323, *312,*322.

Plants of uneatable texture, 348.

Plants, classes of, in relation to
economy of water, 311.

Plants, destruction of, by animals,
345.

Plants, earliest appearance of, 298.

Plants, mimicry by, 347, 348.

Plasmolysis, 52, 53.

Pleurococcus, study of, 244, 245.

Plumule, 7.

Pod, 219, 223.

Poisonous plants, 352.

Poisonous seeds, 24.

Poisons, plants containing, 352.

Pollarded trees, 128.

Pollen, 201, 211, *212.

Pollen-carrying apparatus, 355,
366.

Pollen, discharge of, *211.

Pollen grains, *212.

Pollen grains, number of, per

ovule, 216.
Pollen, protection of, from visitors,

360-362.
Pollen, protection of, from rain,

*371, 372.

Pollen tubes, 212, 213, *214.
Pollination, 353-355.
Polypetalous, 201.
Polysepalous, 201.
Polysiphonia, 255.
Polytrichum, 281-285.
Pome, 224.

Pond-scum, study of, 241-244*.
Potash in hay, 165.
Potato tuber, 76, *78, 114-116.
Prickle, *349.
Prickly leaves, *349.
Prickly pear, *315.
Primary root, 36.
Primrose, pollination in flowers of,

*366, 367.
Procainbium, *96.
Prosenchyma, 94, 95.
Propagation, by root, 61.
Propagation, means of, among

cryptogams, 373.
Propagation of plants, 373-386*.
Protection of plants from animals,

345-352.
Protection of pollen from rain,

*371, 372.
Proteids, 22, 23.
Proteids, tests for, 23.
Prothallium, 287, *289.
Protococcus, *244.
Protonema, 283.
Protoplasm, 52, 178.
Protoplasm, characteristics of, 181,

182.

408

FOUNDATIONS OF BOTANY

Protoplasm, circulation of, *184,

185.

Protoplasm, continuity of, 146.
Pteridophytes, 232.
Pteridophytes, remarks on, 286,

295-297.

Puccinia, study of, 259-262*.
Pulvini, 145, *146.

Race, 230.
Raceme, *186.
Raspberry, *374.
Ray, medullary, 45.
Ray-flowers, 188, *189.
Receptacle, 199.
Red clover, leaf of, *144.
Regions of vegetation, 324.
Regular flowers, 198.
" Reindeer moss," 274.
Reproduction in algse, 256.
Reproduction in ferns, 287, *288,

*289, 291.
Reproduction in flowering plants,

212-215*.
Reproduction in fungi, *258, *259,

*260, *261, *262, *265, *266,

*268, *270.
Reproduction in morning-glory,

390, 391.

Reproduction in mosses, *284, 285.
Resin passage, *93.
Respiration, 172, 173.
Retuse, *131.
Rhachis, 287, *288.
Rhizoids, hairs serving as roots in

mosses and liverworts, *282,

*289.

Rhizopus, study of, 257, 258, 259.
Rhodophycese, 232.
Rhubarb roots, *47.
Ring, annual, *100, *101.

Ringent, *203.

Rise of water in stems, 108-113.

Rockweed, study of, 250-252*.

Root, 36-61.

Root, adaptation to work, 59, 60.

Root-cap, *42.

Root-climbers, *39, 73.

Root, dicotyledonous, section, *44.

Root, elongation of, 30, 31.

Root, exogenous, *44.

Root, fleshy, 45, 46, *47.

Root-hair, 31, *32, *49, 50.

Root-pressure, 54, *55.

Root-section, *42, *44.

Root-sheath or root-pocket, 37.

Root-system, 47, 48.

Roots, absorbing surface of, 49,

. 50.

Roots, absorption and temperature,

55, 56.

Roots, adventitious, 36.
Roots, aerial, 36, *37, *38, *39.
Roots, brace-, *38.
Roots, fascicled, *41.
Roots, fibrous, *41.
Roots, growth of, 30, 31.
Roots, hemlock, lateral extension

of, *60.
Roots, movements of young, 56,

*57, *58, 59.
Roots, parasitic, 39, *40.
Roots, primary, 36.
Roots, propagation by, 61.
Roots, selective action of, 54.
Roots, soil-, 36.
Roots, storage of nourishment in,

46, *47.

Roots, structure of, 41-46.
Roots, water, 37.
Rootstock, 75, *76, *77.
Rotation of protoplasm, *184, 185.

INDEX

409

Round-leafed mallow, stamens and

pistils of, 364.
Russian thistle, *379.
Russian thistle, spread of, 394.
Rust, 259.

Rust, wheat, study of, 259-262*.
Rye grass, 76.

Sage, pollination in flowers of,

*365, *366.
Sago-palm, 113.
Salver-shaped, *202.
Salvinia, *302.
Sap, descent of, *109, 110.
Sap, rise of, 107, 108, *109.
Saprophytes, 169, 269.
Sapwood, 105.
Scalloped, *132.
Schizomycetes, 232.
Schizophycese, 232, *238.
Scirpus, cross-section of stem of,

*84.

Sclerenchyma, 84.
Scouring-rush, study of, 292-295*.
Seasonal plants, 311.
Secondary growth, *96, *97, *100.
Secondary root, 36.
Secondary roots, direction of, 59.
Sections, leaf, *151, *154.
Sections, root, *42, *44.
Sections, wood, *100, *101, *102.
Sedge, rootstock of, *76.
Seed, 5-24.
Seed-leaf, *6, 7.
Seedlings, 25-35.

Seedlings, mutilated growth of, 14.
Seed-plants, 231, 233.
Seed-plants, classes of, 233.
Seeds, containing poisons, 24.
Seeds, dispersal of, 377-386*.
Selection, natural, 395.

Selective absorption, 53, 54.

Self-pollination, 353.

Sepal, 197.

Separated flowers, 199, 200, *201.

Sequoia, *66, 71, *106. .

Series, plants form a, 300.

Serrate, *132.

Sexual generation, 278.

Shade plants, *321.

Shoot, 30.

Shrubs, 69, 70.

Sieve-cells, *93, 110.

Sieve-plate, *93.

Sieve-tubes, *93.

Silica, 165, 241, 294.

Simple leaves, 137.

Simple pistil, 202.

Simple umbel of cherry, *187.

Sinuate, *132.

Sleep of leaves, *144, *145.

Slime-fungi, 232.

Slime moulds, 178, *179, 180, 181,

*236, 237.
"Smilax," 79, *81.
Snowflake, pollen tube of, with

generative cells, *214.
Solomon's seal, parallel-veined leaf

of, *136.
Soredia, 271.
Sori, 261, 287, *288.
Spatulate, *131.
Species, 229.
Spermagones, 271.
Spermatia, 271.
Spike, 188.

Spine, *347, *348, *350.
Spiral vessel, *92.
Spirogyra, study of, 241, 242, *243,

244.

Sporangium, 287, *288.
Spore, 235, *236.

410

FOUNDATIONS OF BOTANY

Spore-capsules, 281.

Spore-cases, *258, *259.

Spore-fruits, *254.

Spore-plants, 231, 232.

Spore-plants, classes of, 232.

Spore-sacs, 263, 270, 273.

Spores of slime moulds, 180.

Sporophyll, 294.

Sporophyte, 281, *282, 284, 285,
289, 291.

Spruce, fertilized ovule of, *303.

Squash seed, 5, 6.

Squash seed, section, *6.

Squash seedling, 25-27.

Stamen, *197, 201, 202, *203.

Stamen, parts of, *203.

Standard, *199.

Starch, 17-20, *19.

Starch disappears during germi-
nation, 21.

Starch in leaves, 169, *170.

Starch-making, rate of, 170, 171.

Starch, testing seed for, 18.

Stem, 30-117.

Stem, definition of, 62.

Stem, dicotyledonous, annual,
gross structure of, 86, *87.

Stem, dicotyledonous, minute
structure of, 86-98*.

Stem, early history of, *95, 96.

Stem, functions of cells of, 105,
106, 107.

Stem, modifiability of, 79-82*.

Stem, monocotyledonous, *83, *84,
*85, 86.

Stem, structure of, 83-103*.

Stemless plants, *72, 73.

Stems, 62-118.

Stems, climbing, 74, *75.

Stems, storage of food in, 113-115.

Stems, twining, *75.

Stem-structure, early history of,
*95, 96.

Sterigmata, *266.

Sterilization, 238.

Stigma, 201, *203.

Stigma, structure of, 213-215*.

Stinging hair, *184.

Stipa. cross-section of rolled and
unrolled leaves of, *318.

Stipe, *264, 265.

Stipules, *135, 136.

Stolon, with tips rooting, *374.

Stomata, 104,*151, *152,*153,*154.

Stomata, operation of, 158, 159.

Stone-fruit, 224.

Storage of food in the root, 46, *47.

Storage of food in the stem, 113-
117.

Strawberry, *226.

Struggle for existence, 387-394.

Study of buttercup flower, 195, 196.

Study of lemon, 217, 218.

Study of tomato, 217.

Study of trilliuin flower, 192, 193.

Study of tulip flower, 194, 195.

Style, 201, *203.

Sugar, 13, 116, .117, 168, 171, 172.

Sugar, formed during germination,
13.

Sugar-cane, cross-section of a bun-
dle from, *110.

Sundew, *341, *342, 343.

Sun-plants, *321.

Supernumerary buds, 122, *123,
*124.

Survival of the fittest, 394, 395.

Swarmspores, 180.

Sweet pea, flowers, *199.

Symbiont, 340.

Symbiosis, 273, 340.

Symmetrical, 198.

INDEX

411

Taper-pointed, *131.

Taproot, *41.

Teleutospores, *262.

Temperature and root-absorption,
55, 56.

Temperature, relation to germina-
tion, 9.

Tendril, *138.

Tendril climbers, *74.

Terminal bud, 63, 121, 122, *124,
*125.

Terminal flowers, 186, *191.

Tertiary root, 36.

Testa, 6.

Tetraspores, *255.

Thallophytes, 232, 235-275.

Thallophytes, study of, 237-273*.

Thallus, 235, 250.

Thermostat, 9.

Thistle, Russian, *379, 394.

Thorns as branches, 68, *69.

Thyme, stoma of, *153.

Tickle-grass, *381.

"Timber line," *329, *330.

Tissue, 94, 95.

Tomato, study of, 217.

Tracheids, 92, 93, *94.

Transition from stamens to petals,
*209.

Transpiration, 156.

Transpiration, amount of, 164, 165.

Transpiration, measurement of,
159, *160, 161.

Transportation by water, 380, 381.

Trees, 69.

Trees, age of, 71.

Trillium, study of flower of, 192,
193.

Trimorphous flowers, 367.
Tropseolum leaf , *132.
Tropseolum leaves, starch in, *170.

Tropaeolum, petiole, coiling of,* 75.

Tropical vegetation, 324, 325.

Tropophytes, 311, 318, 319.

Truncate, *131.

Trunk, *66, *67.

Tuber, 76, *78.

Tubercles on clover roots, *339.

Tubular corolla, *203.

Tulip, study of flower of, 194, 195.

Tumble-weeds, 378, *379, *380.

Turgescence, 184.

Turnip, seedling, *32.

Twayblade, beetle on flower of,

*359.

Twigs, study of, 62-64.
Twiners, 74, *75.
Twining, rate of, 74, 75.
Types, order of appearance of,

298-305.

Umbel, *187.

Umbellet, 190.

Underground stems, 75, *765 *77,

*78, *79.

Uneatable plants, 348.
Union of pistils, 202, 203.
Union of stamens, 201, 202.
Uredospores, 261, *262.
Usnia, *271.

Vacuole, contractile, 180.

Variety, 229, 230.

Vaucheria, study of, 245, *246,

247.

Vegetable physiology, 1.
Vegetation, alpine, 328, *329, *330,

*331.

Vegetation, aquatic, 332, 333.
Vegetation, arctic, 327, *328.
Vegetation, regions of, 324.
Vegetation, temperate, 325, 326.

412

FOUNDATIONS OF BOTANY

Vegetation, tropical, 324, 325.
Vegetative organs, 30.
Vein, 130, *133, *136.
Veining, *133, *136.
Venation, *133, 134, 135, *136.
Venus flytrap, *343, 344.
Vernation, 125, *126, 127.
Vertically placed leaves, 146, *147,

148.

Vessel, *92, 106.
Volva, *265.

Water, absorption by roots, 53-55.
Water, amount transpired, 159-

165.
Water, course through leaf, 163,

164.

Water, excretion of, 172, 173.
Water, movement of, 107, *108,

*109, *110, 111, 112, 113.
Water, relation to germination, 10.
Water-lily, white, insertion of

floral organs, *205.
Water-lily, white, transitions from

petals to stamens in, *209.
Water roots, 37.
Weapons of plants, 349-351*.
Wedge-shaped, *131.
Weeds, 387-390.
Weeds, study of, 388, 389.
Wheat-grain, section of, *19.

Wheat rust, study of, 259-262*.

Wheel-shaped, *202.

Whorled, *293, 294.

Willow, adventitious buds of, 128.

Willow, arctic, *328.

Willow, flowers of, *201.

Wilting, 111.

Wind-pollination, 354.

Windsor bean sprouting over mer-
cury, 56, *57.

Winged fruits, 377, *378.

Wings, *199.

Wood, coniferous, structure of, 92,
*93, *94.

Wood of linden, *100.

Wood sections, *100, *101, *102.

Wood, structure of, *93, *100,
*101.

Wood-cell, *89, *91, *101.

Wood-parenchyuia, 94.

Xanthoria, *271.
Xerophytes, 311, 313-317*.

Yarrow, head of, *189.
Yeast, study of, 266-270, *268.
Yucca, 335.

Zones, vegetation of, 324-328.
Zoospores, 236, *244.
Zygospores, 236, *243, *259.

BERGEN'S BOTANY

KEY AND FLORA

NORTHERN AND CENTRAL STATES
EDITION

JOSEPH Y. BERGEN, A.M.

INSTRUCTOR IN BIOLOGY, ENGLISH HIGH SCHOOL, BOSTON

BOSTON, U.S.A.
GINN & COMPANY, PUBLISHERS

1901

ALL BIGHTS KESEEVED

PREFACE

THIS flora furnishes a key to the commoner spring-flower-
ing families of Phanerogams and descriptions of the charac-
teristics of these families, together with such genera and
species under each as seem most available for school study in
the central and northeastern states. The descriptions have
been in part compiled by the author from various sources,
and in part written with the plants themselves in hand. The
characterizations of many families and of some genera are
taken with slight simplifications from Hooker's Student's
Flora of the British Islands; a few are from Warming's
Systematic Botany. The remainder are mostly adapted from
the floras of Gray and Wood, from Sargent's Silva of North
America, and from Britton and Brown's illustrated Flora of
the Northern States and Canada.

The sequence of the families (and sometimes the genera
under their respective families) is based on Engler's Syllabus
der Pflanzenfamilien, which has also been followed as regards
nomenclature of families. In other regards the sixth edition
of Gray's Manual, and Bailey's revision of Gray's Field, Forest,
and Garden Botany have been followed as authorities. Valu-
able information concerning the precise time of flowering of
many species has been derived from Darlington's Flora Cestrica
and Ward's Guide to the Flora of Washington and Vicinity.

By arrangement with Professor S. M. Tracy a considerable
portion of the key and a large number of the following
descriptions have been copied (a little simplified) from his
Flora of the Southeastern States ; these are designated by an
asterisk at the end of each description.

2 PREFACE

Especial acknowledgments are due to Professor Benjamin
L. Bobinson, Director of the Gray Herbarium of Harvard
University, who has given most valuable advice and has
revised the manuscript of the keys and flora, thus contribut-
ing greatly to any value which they may be found to possess.

Much aid has been derived from the careful proof-reading
of Professor J. M. Holzinger of the Minnesota State Normal
School, Professor L. H. Pammel of the Iowa State College,
and Miss Mary P. Anderson of the Somerville, Mass., English
High School. The author wishes heartily to thank these
critics for the many errors which they have corrected and
the valuable additions which they have suggested.

The territory covered overlaps that dealt with by Professor
Tracy in the flora above cited, and nearly meets that embraced
in Miss Eastwood's Flora of the Rocky Mountains and the
Salt Lake Basin, since many of the species treated in the
present work range west as far as the hundredth meridian.

The plants chosen to constitute this flora are those which
bloom during some part of the latter half of the ordinary
school year, and which have* a rather wide territorial range.
Enough forms have been described to afford ample drill in
the determination of species. Gray's Manual of Botany or
Field, Forest, and Garden Botany will of course be employed
by the student who wishes to become familiar with most of
the seed-plants of the region here touched upon. Those
species which occur in the central and northeastern United
States only as cultivated plants are so designated. The illus-
trations are mainly redrawn from German sources. A few
of them are the work of Mr. E. N. Fischer of Boston, but
the greater portion are by Dr. J. W.*Folsom of the Illinois

Industrial University.

J. Y. B,

CAMBRIDGE, MASS., January, 1901.

HOW TO USE THE KEY AND FLORA

IN order to determine an unknown species, the student is
first to make a careful examination of the plant in hand.
After noting in a general way the appearance of the root,
stem, and leaf, including a cross-section of the stem, he
should study the number, coherence, and adnation of the
parts of the flower, then make and draw a cross-section and
a lengthwise section of it. Irregularities in calyx or corolla,
peculiarities in the shape, structure, or operation of the essen-
tial organs, such, for instance, as anthers discharging through
chinks in the end, should be noted.

Next, the inquirer should look carefully through the Key
to the families. He is first to decide whether the plant in
question is a Gymnosperm or an Angiosperm; if not a conif-
erous tree or shrub, it will of course belong to the latter
division. He is then to settle the question whether it is a
Monocotyledon or a Dicotyledon ; then under what division of
the group the plant comes ; and, finally, to decide upon its
family.

Turning now to the page at which the family is described,
a rapid inspection of the characteristics of the genera will
make it evident to which one the species under examination
belongs. It may not infrequently prove that none of the
genera described agree with the plant studied, and in that
case the student must either consult a larger flora or rest
satisfied with having determined the family to which his

4 FOUNDATIONS OF BOTANY

specimen belongs.1 The identification of the species, after
the genus has been reached, presents no difficulty in a little
flora like the present one.

The author does not believe in spending much of the time
of a class upon identifying species, but would rather recom-
mend comparative studies of as many plants of a group as
are accessible, and making these studies thorough enough to
bring out fully the idea of the family, the genus, and the
species.2 The descriptions in this flora may be used as a
check on the cruder ones which the pupil is first to frame for
himself.

1 It will greatly simplify matters if the teacher selects for examination only such
species as are here described.

2 The teacher will find abundant suggestions for such a course in Spalding's
Introduction to Botany, pp. 152-260.

KEY TO THE FAMILIES OF FLOWEKING PLANTS
DESCRIBED IN THIS FLOEA

CLASS I

GYMNOSPERMS. Ovules not enclosed in an ovary.

Trees or shrubs. Leaves tisually evergreen and needle-shaped, awl-shaped, or
scale-like. Flowers monoecious or dioecious. Fruit a scaly cone, or sometimes
appearing berry-like. 1. pine Family, page 13

CLASS II

ANGIOSPERMS. Ovules enclosed in an ovary.

SUBCLASS I. —MONOCOTYLEDONS. Flowers usually with their parts
in threes, never in fives. Leaves usually parallel-veined. Cotyledon 1.

Flowers enclosed by chaffy bracts. FAMILY PAGE
Flowers 2-bracted. Leaves 2-ranked. Stem cylin-
drical 4. Grass 23

Flowers 1-bracted. Leaves 3-ranked. Stem trian-
gular 5. Sedge 23

Flowers on a spadix.

Spadix slender, hairy, and bristly 2. Cat-tail 20

Spadix fleshy ..." 6. Arum 23

Flowers not on a spadix.
Carpels usually numerous and nearly or entirely

separate 3. Water-plantain . 21

Carpels united.
Perianth free or adnate only to the base of the ovary.

Perianth regular, its parts similar, green, or chaffy 9. Kush 29

Perianth of 2 sets, one sepal-like, the other petal-
like.

Style and stigma 1. Petals 3 or 2, soon disap-
pearing 7. Spiderwort ... 26

b FOUNDATIONS OF BOTANY

Styles or stigmas 3, separate. Petals 3, lasting FAMILY PAGE
several days. Leaves netted-veined .... IQ. (Trillium) Lily . 29
Style 1, stigma 3-lobed, or 6-toothed.
Corolla irregular. Aquatic herbs with par-
allel-veined leaves 8. Pickerel-weed . 28

Perianth regular, its divisions all alike, or nearly

so, petal-like 10. Lily 29

Perianth adnate to the ovary.

Anthers 6 11. Amaryllis. . . 42

Anthers 3 12. Iris 45

Anthers lor 2 13> Orchis .... 4(5

SUBCLASS II. — DICOTYLEDONS. Flowers usually with their parts in
fives or fours. Leaves netted-veined. Cotyledons 2.

I. ApetalOUS Division. Flowers without a corolla or without either calyx or
corolla.1

Flowers monoscious or dioecious, one or both sorts in

catkins.

Staminate flowers in catkins, the pistillate ones soli-
tary or clustered.

Leaves pinnately compound ig. "Walnut 49

Leaves simple 18> Beech .... 55

Both kinds of flowers in catkins.
Leaves alternate.
Ovaries in fruit becoming fleshy and combining

into an aggregate fruit 20. Mulberry ... 61

Fruit 1-seeded, a stone-fruit or minute nut. Aro-
matic shrubs 15. Bayberry ... 49

Fruit a capsule, seeds with silky hairs .... 14. "VVillow . 47

Fruit a minute nut or akene. Mostly large shrubs

or trees, not very aromatic 17. Birch 51

Leaves opposite, small parasitic shrubs .... 22. Mistletoe . 63

Flowers not in catkins, both calyx and corolla wan ting 44. Sycamore. . . 105

1 When only one floral envelope is present, this is said to be the calyx and the
corolla is considered to be missing.

KEY

PAGE

Flowers not in catkins ; calyx present, sometimes petal-like.
Trees or shrubs.

Flowers not hypogynous ; plants not climbing . . 73. Dogwood . . . 162
Flowers not hypogynous ; climbing plants .... 24. Dutchman's Pipe 64

Flowers hypogynous.
Style single, not cleft, fruit a key. (Fraxinus) . 78. Olive ..... 175

Style single, not cleft, fruit a stone-fruit .... 37. Laurel ..... 88

Styles 2 or 2-cleft, fruit 1-celled ....... 19. Elm ...... 59

Styles 2 or 2-cleft, fruit 2-celled ....... 58. Maple ..... 140

Styles 3, each 2-cleft. Ovary 3-celled ..... 53. Spurge . . . .135

Herbs.
Flowers not hypogynous ; ovary 6-celled ..... 24. Dutchman's Pipe 64

Flowers not hypogynous ; ovary 1-celled ; flowers in
umbel-like clusters ...... | ..... 23. Sandal wood . . 64

Flowers hypogynous ; ovary 1-celled.
Stamens many ..... -. . ....... 32. Buttercup ... 77

Stamens few.
Stipules sheathing the joints ........ 25. Buckwheat ... 66

Stipules wanting.
Rather fleshy herbs ........... 26. Goosefoot ... 68

Not fleshy.

Ovules on a free central placenta ; delicate,
soft-leaved herbs. (Stellaria) ..... 30. Pink ..... 71

Ovule single. Tough, with awl-shaped leaves.
(Scleranthus) ........... 30. Pink ..... 71

Ovary several-celled.
Small prostrate herb ; leaves spatulate, whorled . 28. Ice-plant .... 69

Stipules present, not sheathing.
Style single .............. 21. Nettle ..... 62

s*yles 2 ............... 20. Mulberry ... 61

Flowers hypogynous, ovary 3-celled ...... 53^ Spurge . .135

Flowers hypogynous, ovary 5-10-celled ; fruit a berry 27. Pokeweed ... 69

II. PolypetalOUS Division. Calyx and corolla both present, the petals not united.

Stamens more than 10.

Trees, shrubs, or woody vines. Leaves alternate.
Ovary 1, simple.
Fruit a stone-fruit ........... 45. Rose m 195

8 FOUNDATIONS OF BOTANY

Ovary 1, compound ; fruit dry. FAMILY PAGE

Ovary 5-celled, 1-2-seeded at maturity .... 63. Linden .... 146

Ovary 3-celled, many-seeded 68. Begonia . . .152

Ovary 1, compound; fruit fleshy 45. Rose 105

Ovaries numerous.
Leaves with, stipules.
Stamens inserted on the receptacle .... 34. Magnolia ... 85

Stamens inserted on the calyx 45. Rose 105

Leaves not with stipules.

Small trees 36. Pawpaw ... 88

Leaves opposite ; fruit dry.

Ovary single, 3-5-celled 43. Saxifrage ... 101

Ovaries several, enclosed by the calyx tube . . 35. Calycanthus . . 87
Herbs.

Ovary single, simple ; fruit a berry 33. Barberry ... 84

Ovaries several, simple.
Stamens inserted on the receptacle ..... 32. Buttercup ... 77

Stamens inserted on the calyx .....'.. 45. Rose 105

Ovary compound.

Aquatic herbs, leaves flat 31. Water-lily . . 75

Marsh herbs, leaves tubular 42. Pitcher-plant . 101

Terrestrial herbs.
Ovary 1-celled.

Placentae central, juice watery ..... 29. Purslane ... 70
Placentae parietal, juice milky or colored . 38. Poppy .... 89

Placentae 2, parietal . 40. Caper .... 99

Placentae 3 or more, parietal.

Leaves alternate 41. Mignonette . . 100

Leaves opposite 65. St. Johnswort . 148

Leaves apparently wanting, stems fleshy . 69. Cactus . . . .154
Ovary several-celled, stamens monadelphous . 64. Mallow .... 147
Ovary 3-celled, stamens not much if at all
monadelphous, stems fleshy, juice watery
and acid 68. Begonia .... 152

Stamens not more than 10.
Trees, shrubs, or woody vines.
Fruit a stone-fruit.
Stamens 2, rarely 3-4 78. Olive 175

KEY

Stamens as many as the petals. FAMILY PAGE

Flowers perfect.

Stamens 4, alternate with the petals ... 73. Dogwood . . . 162
Stamens 5, alternate with the petals . . . 54. Sumac .... 137

Stamens 4-5, opposite the petals 61. Buckthorn . . 143

Fruit a berry.

Stamens alternate with the petals.

Inserted on the calyx, leaves simple .... 43. Saxifrage . . . 101
Inserted on a disk surrounding the ovary,

leaves compound 71. Ginseng . . . 157

Stamens opposite the petals ........ 62. Grape or Vine . 145

Fruit a 2-seeded capsule or a key.

Leaves compound 51. Rue 133

Fruit a 3-5-celled capsule, flowers small, greenish,

or brown-purple, leaves simple 56. Staff Tree . . . 139

Fruit 5-lobed, the 5 carpels separating when ripe,
flowers rather large, white, or of showy colors,

leaves simple 47. Geranium . . . 129

Fruit a 1-3-celled capsule, leaves compound, flowers

irregular 59. Buckeye . . . 142

Fruit a 3-celled bladdery capsule, leaves compound,

flowers regular 57. 'Bladder Nut . . 140

Fruit a legume 46. Pea or Pulse . 117

Herbs.

Ovary single, 1-celled, simple or compound.
Corolla regular, or nearly so.
Sepals and petals 4-5 ; stamens 5, 10, or 12, dis-
tinct.
Leaves alternate.

Stigma single 46. Pea or Pulse . . 117

Stigmas 4 43. Saxifrage ... 101

Leaves opposite, punctate, flowers yellow . . 65. St. Johnswort . 148

Leaves opposite, flowers white or red . . . . 39. Pink 71

Sepals and petals 4-5 ; stamens 5, united ... 67. Passion Flower 151

Sepals 2, petals 4-5 29. Purslane ... 70

Sepals 6, stamens hypogynous, opposite the petals 33. Barberry ... 84
Corolla irregular.

Fruit a legume 46. Pea or Pulse . . 117

Fruit a capsule.

Stamens 5 • . . . 66. Violet .... 149

Stamens 6, in 2 sets 38. Poppy .... 89

10 FOUNDATIONS OF BOTANY

Ovary single, 2-5-celled, fruit dry. FAMILY PAGE

Ovary 2-celled.

Flowers in umbels, stamens 5 72. Parsley .... 158

Flowers not in umbels, petals 4 or 0, stamens 6 . 39. Mustard .... 93
Flowers not in umbels, petals 3, stamens 6 or 8 . 52. Polygala .... 134

Ovary a 4-celled capsule 70. Evening Primrose 156

Ovary of 3 nearly distinct lobes, which become

thick and fleshy in fruit 49. Indian Cress . . 132

Ovary a 5-celled capsule.
Leaves simple.

Parasitic white or yellowish herbs, or ever-
green herbs, not parasitic, capsule many-
seeded 74. Pyrola 164

Terrestrial, not much if at all fleshy, capsule

5-10-seeded 47. Geranium ... 129

Terrestrial, stem fleshy and translucent, cap-
sule elastic, several-seeded 60. Balsam .... 143

Leaves of 3 leaflets 48. Wood-sorrel . . 131

Ovary of 5 principal cells, each more or less divided
by a partition into 2 cells ; seeds flattish, with a

mucilaginous coating 50. Flax 132

Ovary single, 2-5-celled ; fruit a berry 71. Ginseng .... 157

Ovaries 2, seeds hairy-tufted 81. Milkweed . . . 180

III. GamOpetalOUS Division. Calyx and corolla both present, the petals more
or less united.

Trees, shrubs, or woody vines.
Leaves alternate.
Fruit splitting open.

Fruit a legume 46. Pea or Pulse . . 117

Fruit a 5-celled capsule 75. Heath 166

Fruit not splitting open, a stone-fruit . . . .55. Holly 138

Fruit a berry.

Ovary not adnate to the calyx ; seeds few, large 77. Ebony 174

Ovary not adnate to the calyx ; seeds many,

small 88. Nightshade ... 198

Ovary adnate to the calyx 75. Heath 166

Leaves opposite.

Fruit a 2-celled, 2-seeded capsule 95. Madder .... 212

Fruit a 2-celled, many-seeded capsule.
Seeds winged 90. Bignonia . ... 206

KEY 11

•

FAMILY PAGE

Seeds not winged ; shrubs 96. Honeysuckle . 215

Fruit a 5-celled capsule 75. Heath 166

Fruit a stone-fruit or berry.

Fruit 1-2-seeded ; stamens 2 78. Olive 175

Fruit 1^4-seeded ; stamens 4 86. Verbena . . . 192

Fruit 1-5-seeded ; stamens 5 96. Honeysuckle . 215

Herbs.

Ovary not adnate to the calyx, flowers regular.
Ovary separating into 2 distinct follicles.

Style single, stamens distinct . 80. Dogbane . . . 178

Styles 2, stamens united 81. Milkweed . . . 180

Ovary 1-celled.

Fruit a legume 46. Pea or Pulse . 117

Fruit a capsule.
Leaves alternate.

Stamens opposite the lobes of the corolla . 76. Primrose . . .171
Stamens alternate with the lobes of the

corolla 84. Waterleaf ... 187

Leaves opposite 79. Gentian .... 177

Leaves all reduced to mere scales, plants never

green, root-parasites 91. Broom-rape . . 208

Ovary 2-several-celled.

Stamens 2 or 4 94. Plantain ... 211

Stamens 5, cells of the ovary 1-2-seeded.

Fruit separating into 4 nutlets 85. Borage . . . .188

Fruit a capsule 82. Morning-glory . 183

Stamens 5, cells of the ovary several-seeded.

Stigma l 88. Nightshade . . 198

Stigmas 3 83. Phlox .... 185

Ovary not adnate to the calyx, flowers irregular.
Ovary 1-celled.

Fruit a legume 46. Pea or Pulse . 117

Fruit a capsule 92. Bladderwort . . 209

Ovary 2-4-celled.

Cells each 1-seeded.

Ovary deeply 4-lobed 87. Mint 193

Ovary not deeply lobed.

Stamens 2 or 4 86. Verbena . . . 192

Stamens 8 52. Polygala . . . 134

Cells each 2-several-seeded.

12 FOUNDATIONS OF BOTANY

FAMILY PAGE

Corolla lobes imbricated in the bud .... 89. Figwort .... 201
Corolla lobes convolute in the bud .... 93. Acanthus . . . 210
Ovary adnate to the calyx tube.

Flowers in an involucrate head 100. Composite . . 224

Flowers not in heads.
Stamens 3.

Leaves opposite 97. Valerian ... 220

Leaves alternate 98. Gourd .... 221

Stamens 4-5.

Leaves alternate 99. Campanula . . 223

Leaves opposite or whorled 95. Madder .... 212

CLASS L — GYMNOSPERMS.

Plants destitute of a closed ovary, style, or stigma. Ovules
generally borne naked on a carpellary scale, which forms part
of a cone. Cotyledons often several (Fig. 1).

1. CONIFERJE. PINE FAMILY.

Trees or shrubs with wood of peculiar structure (Part I,
Ch. VI), destitute of ducts, with resinous and aromatic juice.
Leaves generally evergreen, and needle-shaped or awl-shaped.
Flowers destitute of floral envelopes, monoecious or dioecious,
the staminate ones consisting of catkin-like spikes of stamens
and the pistillate ones consisting of ovule-bearing scales,
arranged in spikes, which ripen into cones.

Each scale of the cone borne in the axil of a bract. Seeds 2, with
wings.

Leaves evergreen, in bundles of 2-5. Finns, I.

Leaves evergreen, solitary, sessile, keeled on both surfaces.

Picea, II.

Leaves evergreen, solitary, petioled, flat. Tsuga, III.

Leaves solitary, evergreen, flat above, keeled below. Abies, IV.
Leaves clustered, deciduous, flat. Larix, V.

Scales of the cone without bracts, cone becoming globular and woody.
Leaves linear.

Leaves alternate, deciduous. Taxodium, VI.

14 FOUNDATIONS OF BOTANY

Scales of the cone few, without bracts. Leaves evergreen, generally
scale-like or awl-shaped.

Cones dry and thin-scaled. Thuya, VII.

Cones berry-like. Juniperus, VIII.

I. PINUS, Tourn.

Sterile flowers somewhat resembling inconspicuous catkins,
borne at the base of the young shoot of the season, each
flower consisting of pollen-scales in spiral groups (Fig. 1, 2).
Fertile flower-spikes which consist of spirally arranged carpel-
scales, each scale springing from the axil of a bract and bear-
ing at its own base two ovules (Fig. 1, 3). Fruit a cone,
formed of the thickened carpellary scales, ripening the second
autumn after the flower opens. Primary leaves, thin and
chaffy bud-scales, from the axils of which spring the bundles
of 2-5 nearly persistent, needle-like, evergreen leaves, from
1-15 in. long (Fig. 1).

1. P. Strobus, L. WHITE PINE. A tall tree, 75-160 ft. high,
much branched and spreading when growing in open ground, but
often with few or no living branches below the height of 100 ft.
when growing in dense forests. Leaves clustered in fives, slender,
3-4 in. long, smooth, and pale, or with a whitish bloom. Cones
5-6 in. long, not stout. The wood is soft, durable, does not readily
warp, and is therefore very valuable for lumber. In light soil, com-
monest N.

2. P. Taeda, L. LOBLOLLY PINE, OLDFIELD PINE. A large
tree ; bark very thick and deeply furrowed, becoming flaky with age,
twigs scaly. Leaves in threes, 6-10 in. long, slender, very flexible ;
sheaths §-1 in. long. Cones solitary, oblong-conical, 3-5 in. long ;
scales thickened at the apex, the transverse ridge very prominent
and armed with a short, stout, straight, or recurved spine. Common
and often springing up in old fields ; trunk containing a large pro-
portion of sap wood ; timber of little value for outside work.*1

3. P. rigida, Mill. NORTHERN PITCH PINE. A stout tree,
30-80 ft. high, with rough scaly bark. Leaves in threes, 3-5 in.
long, stiff and flattened. Cones ovoid-conical, 2-3 in. long, their

1 Descriptions followed by an asterisk are taken (more or less simplified) from
Professor Tracy's flora in the Southern States Edition.

GYMNOSPERMS

scales tipped with a short, abruptly curved spine. Wood hard,
coarse and resinous, mainly used for fuel. Poor, sandy soil,
especially eastward.

FIG. 1. — Scotch Pine (P. sylvestris).

1, a twig showing : a, staminate catkins ; b, pistillate catkins ; c, a cone ; d, needles.
2, an anther, a, side view ; b, outer surface. 3, a carpel-scale, a, inner surface ;
b, outer surface. 4, a cone-scale, a seed-wing, and a seed. 5, section of a seed,
showing the embryo. (1) is natural size ; the other parts of the figure are magni-
fied by the amount indicated by comparison with the vertical line alongside each.

4. P. inops, Ait. SCRUB PINE. A small tree, usually 20-30 ft.
high, but sometimes much taller ; bark of the trunk rough, nearly
black; twigs smooth and with a bloom. Leaves in twos, 1-2 in.

16 FOUNDATIONS OF BOTANY

long, rigid, sheaths very short. Staminate catkins dull yellowish-
purple, 1 in. long. Cones solitary, short-peduncled, often reflexed,
ellipsoid-conic, about 2 in. long ; scales thickened at the apex and
armed with a slender, straight, or recurved prickle. On dry, sandy
soil ; wood light, soft, weak, and of little value.*

5. P. sylvestris, L. SCOTCH PINE (wrongly called Scotch Fir). A
medium-sized tree, with the older bark reddish and scaly. Leaves in
twos, 1|— 2^ in. long. Cones rather small and tapering (Fig. 1, I c).
Cultivated from Europe.

6. P. resinosa, Ait. RED PINE, NORWAY PINE. A tall, rather
slender tree, with bark reddish-brown and moderately smooth.
Leaves in twos, slender, and 5-6 in. long. Cones borne at the ends
of the branches, smooth, about 2 in. long. A valuable timber tree,
which often grows in small, scattered clumps ; wood firm, pale red,
and not very resinous ; used in house and bridge building, and for
masts and spars.

7. P. palustris, Mill. LONG-LEAVED PINE. A large tree ; bark
thin-scaled, wood very resinous, old trees with only a few spreading
branches near the top. Leaves in threes, 10—15 in. long. Sheaths
1-1£ in. long, crowded near the ends of very scaly twigs. Staminate
catkins 2-3 in. long, bright purple, conspicuous. Cones terminal,
ellipsoid -conical, 6-10 in. long, diameter 2-3 in. before opening, 4-6
in. when fully opened ; scales much thickened at the apex and armed
with a short recurved spine at the end. The most common tree in
the pine barrens ; wood hard, strong, and durable, especially valua-
ble for floors and inside work.*

II. PICEA, Link.

Sterile flowers generally axillary (sometimes terminal), borne
on the twigs of the preceding year. Fertile flowers terminal.
Fruit a nodding, thin-scaled cone, ripening in the first autumn.
Leaves evergreen, needle-shaped, four-angled, scattered or
spirally arranged.

1. P. nigra, Link. BLACK SPRUCE. A small tree, usually only
20 or 30 ft. high, often less. Leaves strongly 4-angled, bluish-green,
and glaucous, ^-f in. long. Cones ovoid, pointed, £-l£ in., usually
about 1 in. long, persisting sometimes for 20-30 years. Wood of
little value except for paper-pulp. The tree is especially abundant
northward, and is of common occurrence in peat-bogs.

2. P. rubra, Dietrich. RED SPRUCE. A large tree, 70-80 or even
100 or more feet high, of strict conical habit. Leaves dark green
or yellowish and glossy, |— | long. Cones ovoid-oblong, acute, usually
l£-2 in. long, mostly falling the first year. This is the principal

GYMNOSPERMS 17

timber-spruce of the northeastern United States, and furnishes much
rather tough lumber for use in floor-joists, scantling, and similar
purposes.

3. P. alba, Link. WHITE SPRUCE, SKUNK SPRUCE, CAT SPRUCE.
A tall, rather conical tree, 60-70 ft. high. Leaves pale and with a
bloom sometimes f in. long. Cones cylindrical, with rounded ends,
about 2 in. long, falling inside of one year. A handsome tree,
valuable for timber, ranging far northward.

4. P. excelsa, Link. NORWAY SPRUCE. A large tree. Leaves
dark green, f-1 in. long. Cones 5-7 in. long. Cultivated from
Europe.

III. TSUGA, Carriere.

Sterile flowers, clusters of stamens springing from the axils
of leaves of the preceding year. Cones terminal, on twigs of
the preceding year, drooping, thin-scaled, ripening the first
year. Leaves minutely petioled, short, flat, white beneath,
2-ranked.

1. T. canadensis, Carriere. HEMLOCK. A large tree, in age
branchless below when growing in dense woods. When young the
spray is very graceful and abundant. Leaves short-linear. Cones
^ in. or less in length. The wrood is coarse and splintery, but useful
for fences and other rough work. The thick reddish bark is of
great value for tanning.

IV. ABIES, Link.

Sterile flowers from axils of leaves of the preceding year.
Cones erect, on the sides of the branches, with deciduous
scales, ripening the first year. Leaves scattered, but on hori-
zontal branches appearing 2-ranked, flat above, silvery, and
with a prominent midrib below.

1. A. balsamea, Miller. BALSAM FIR. A slender tree, 50-60
ft., occasionally 80 ft., high, with dense foliage. Leaves narrowly
linear, less than 1 in. long. Cones violet-colored until old, cylindri-
cal, 2-4 in. long. The bark contains many large blisters, filled with
the well-known Canada balsam. The wood is brittle, and of little
value.

V. LARIX, Tourm.

Flower-spikes short, opening in early spring, before the
leaves ; the fertile ones, while still young, of a beautiful crim-

18 FOUNDATIONS OF BOTANY

son color. Fruit a small cone, with thin scales. Leaves none
of them scaly, but all needle-shaped, soft, deciduous, very
numerous, in little brush-like bundles.

1. L. americana, Michx. AMERICAN LARCH, TAMARACK, HACK-
MATACK (wrongly, but quite generally, called Cypress and Juniper).
A tall, slender tree, 30-100 ft. high. Leaves slender and less than
1 in. long, very pale bluish-green. Cones £-f in. long, few-scaled.
Wood hard, tough, and heavy, of considerable use for ship-building.

2. L. europaea, DC. EUROPEAN LARCH. Leaves bright green
and longer ; cones longer than in the preceding species and many-
scaled. Cultivated from Europe.

VI. TAXODIUM, Richard.

Trees ; leaves spreading so as to appear 2-ranked, decidu-
ous ; flowers monoecious, appearing before the leaves ; stain i-
nate ones numerous, globose ; forming long, terminal, drooping,
panicled spikes ; anthers 2-5-celled ; pistillate flowers single
or in pairs, bractless, the peltate scales 2-ovuled ; cone globose ;
the very thick woody scales angular, separating at maturity ;
seeds 3-angled, pyramidal.*

1. T. distichum, Richard. BALD CYPRESS. A very large tree;
bark dark brown, rough, fibrous ; many of the twigs deciduous witli
the leaves. Leaves alternate, opposite, or whorled, 2-ranked, flat,
linear, £-f in. long. Cones terminal, globose, about 1 in. in diameter ;
ends of the scales much thickened, wrinkled, and with a distinct
triangular marking. Common in swamps and on the borders of
streams; wood reddish, soft, light; specially valuable for shingles
and fence posts, and for boat-building.*

VII. THUYA, Tourn.

Flowers small, terminal, monoecious, on different branches.
Stamens each consisting of a scale-like portion bearing 4 anther-
cells. Pistillate flowers consisting of a few overlapping scales
which ripen into a small, loose cone. Leaves evergreen, oppo-
site, and closely overlapping on the stem, of two kinds, those
on the more rapidly growing twigs awl-shaped, the others mere
scales.

1. T. occidentalis, L. ARBOR VIT^E, CEDAR. A small tree, 20-50
ft. high, with soft fibrous bark. Leaves mostly awl-shaped and blunt.

GYMNOSPERMS 19

Cones ellipsoidal, their scales 2-seeded. Grows on rocky ledges, but
reaches its greatest size in cool cedar swamps. Wood soft, yellowish,
fragrant, durable, prized for shingles and fence posts.

VIII. JUNIPERUS, L.

Flowers very small, lateral, dioecious, or sometimes monoe-
cious. Scales of the staminate flower shield-shaped, with 3-6
anther-cells. Fertile flowers with 3-6 fleshy scales which
unite into a berry-like, 1-3-seeded fruit. Leaves awl-shaped
or scale-shaped.

1. J. communis, L. JUNIPER. A low, spreading shrub (one
variety prostrate in circular masses). Leaves linear-awl-shaped, with
needle-like points, each marked with a distinct stripe of bloom along
the center of the upper surface, borne in whorls of three. Fruit a
dark blue aromatic berry, £ in. or more in diameter. Grows in dry
pastures and on sterile hillsides N.

2. J. virginiana, L. RED CEDAR, SAVIN. Ranges in size and
shape from a low, rather erect, shrub to a conical tree 90 ft. high.
Leaves of two kinds, those on the rapidly growing shoots awl-shaped
and pointed, those on the shortest twigs scale-shaped, obtuse, or
nearly so, and closely appressed to the stem. Fruit small, bluish,
with a white bloom. Found all the way from British America to
Florida. Wood soft, fragrant, reddish, exceedingly durable in the
ground, valued for the manufacture of moth-proof chests and espe
cially for lead-pencils.

20 FOUNDATIONS OF BOTANY

CLASS II. — ANGIOSPERMS.

Plants with a closed ovary, in which the seeds are matured.
Cotyledons 1 or 2.

SUBCLASS I. — MONOCOTYLEDOKOUS PLANTS.

Stems with the fibro-vascular bundles scattered among the
parenchyma cells ; in perennial plants no annual rings of
wood. Leaves usually parallel-veined, alternate, nearly
always entire. Parts of the flower generally in threes
(never in fives). Cotyledon 1.

2. TYPHACE^J. CAT-TAIL FAMILY.

Perennial marsh or aquatic plants. Eootstock stout, creep-
ing; stem simple, cylindrical, erect. Leaves simple, strap-
shaped, sheathing at the base, nerved and striate. Flowers
monoecious, in a single terminal spike, staminate part of the
spike uppermost, each part subtended by spathe-like deciduous
bracts ; perianth of fine bristles ; staminate flowers sessile ;
stamens 2-7. Filaments connate, subtended by minute bracts ;
pistillate flowers short-pediceled. Ovary 1-2-celled ; styles
1-2. Fruit small, nut-like.*

TYPHA, Tourn.
Characters of the family.

1. T. latifolia, L. CAT-TAIL. Stem erect, jointed below, 5-8 ft.
high. Leaves nearly as long as the stem, about 1 in. wide, netted
and with a bloom. Spike cylindrical, dark brown or black ; staminate
portion above the pistillate, usually without any interval between
them, each 4-8 in. long and about 1 in. in diameter. Fruit furrowed.
Common in marshes and shallow ponds.*

MONOCOTYLEDONOUS PLANTS 21

3. ALISMACE^. WATER-PLANTAIN FAMILY.

Annual or perennial marsh herbs, usually with creeping run-
ners or rootstocks. Stems scape-like. Leaves long-petioled,
sheathing at the base ; petiole rounded ; blade nerved, netted,
or sometimes wanting. Flowers in racemes or panicles, per-
fect, monoecious or dioecious ; pedicels in bracted whorls.
Sepals 3, persistent, petals 3 or wanting. Stamens 6 or more.
Ovaries few or many, 1-celled, 1-seeded. Style short or none.
Fruit a 1-seeded akene.*

I. ALISMA, L.

Annual or perennial herbs. Leaves erect or floating, blades
prominently ribbed and netted, or even pinnately veined.
Scapes erect, becoming longer than the leaves, cylindrical,
spongy. Flowers perfect, in paniculate 3-bracted umbels,
small, white or pink. Stamens 6-9. Ovaries numerous in
one or more whorls on a flat receptacle. Fruit 1-seeded
akenes which are ribbed on the back and sides.*

1. A. Plantago, L. WATER PLANTAIN. Perennial; root fibrous.
Leaves ovate or somewhat cordate, 5-7-nerved when erect, floating
leaves narrower and sometimes linear. Scapes usually single ; pan-
icle 1-2 ft. long ; flowering branches whorled, subtended by three
narrow, striate bracts ; pedicels slender, elongated. Ovaries 15—20
in a single whorl ; base of the short style persistent, forming a beak
at the inner angle of the akene. Akenes obliquely obovate, 2-3-
keeled on the back. Common in ponds and muddy places.*

II. SAGITTARIA.

Perennial ; rootstocks mostly knobby or tuber-bearing.
Scapes erect or decumbent. Leaves long-petioled, sheathing
at the base, the blade round and netted, or wanting. Flowers
monoecious or dioecious, racemed in 3-bracted whorls of threes,
the upper flowers usually staminate. Sepals 3, persistent.
Petals 3, withering-persistent or deciduous. Stamens few or
many. Ovaries in globose heads, 1-ovuled ; style short, per-
sistent. Fruit a subglobose head of flattened akenes.*

FOUNDATIONS OF BOTANY

1. S. variabilis, var. latifolia, Willd. BROAD-LEAVED ARROW-
HEAD. Leaves very variable in size and shape, from broadly
sagittate to linear ; those growing on the drier soil being usually the
broader ; petioles 6-30 in. long. Scape smooth or slightly downy,
6-36 in. high; bracts acute. Flowers monoecious or sometimes
dioecious, white, 1 in. or more in width; pedicels of the staminate
flowers twice the length of those of the fertile flowers. Filaments
long, smooth, and slender. Akenes with beak nearly horizontal.
Ditches and muddy places.*

2. S. graminea, Michx. GRASS-LEAVED SAGITTARIA. Leaves
long-petioled, lanceolate, or elliptical, and acute at each end, 3-5-
nerved, or often linear, the earlier

often reduced to flattened petioles.
Scape slender, usually longer than
the leaves, simple, weak, often pros-
trate in fruit; bracts small, ovate,
connate at the base. Flowers monoe-
cious o» dioecious, on long, thread-
like pedicels, about £ in. wide.
Stamens 10-20, filaments downy.
Akenes nearly beakless. In ditches
arid shallow pools.*

FIG. 2. — Diagram of Inflorescence
of a Grass.

, sterile glumes ; P15 a flowering glume ;
P2, a scaly bract (palea) ; e, transparent
scales (lodicules) at the base of the
flower ; B, the flower.

FIG. 3.— Fescue-grass (Festuca
pratensis).

A, spikelet (compare Fig. 2) ; B, a
flower, the lodicules in front and
the palea behind ; C, a lodicule ;
Z), ovary.

MONOCOTYLEDONOUS PLANTS 28

4. GRAMINEJE. GRASS FAMILY.

Mostly herbs, with usually hollow stems, closed and en-
larged at the nodes. Leaves alternate, in two ranks, with
sheathing bases, which are split open on the side opposite the
blade. Flowers nearly or quite destitute of floral envelopes,
solitary, and borne in the axils of scaly bracts called glumes,
which are arranged in two ranks overlapping each other on
1-many-flowered spikelets ; these are variously grouped in
spikes, panicles, and so on. Fruit a grain. (The family is
too difficult for the beginner, but the structure and group-
ing of the flowers may be gathered from a careful study of
Figs. 2, 3.)

5. CYPERACEJE. SEDGE FAMILY.

Grass-like or rush-like herbs, with solid, usually triangular,
stems, growing in tufts. The sheathing base of the generally
3-ranked leaves, when present, is not slit as in grasses. The
flowers are usually somewhat less enclosed by bracts than
those of grasses ; the perianth is absent or rudimentary ;
stamens generally 3 ; style 2-cleft or 3-cleft.

The general appearance of a common sedge may be learned
from Part I, Ch. V, and the flower-cluster and the flower
understood from an inspection of Fig. 4.

The species are even more difficult to determine than those
of grasses.

6. ARACE-ffi. ARUM FAMILY.

Perennial herbs, with pungent or acrid juice, leaves often
netted-veined, small flowers (perfect or imperfect) clustered
along a peculiar fleshy spike called a spadix, and frequently
more or less covered by a large, hood-like bract called a
spathe. Perianth, when present, of 4-6 parts ; often want-
ing. Fruit usually a berry.

FOUNDATIONS OF BOTANY

FIG. 4.— Inflorescence, Flower, and Seed, of a Sedge.
(Great Bulrush, Scirpus lacustris.)

A, magnified flower, surrounded by a perianth of hypogynous bristles ; £, the
seed ; C, section of the seed, showing the small embryo enclosed hi the base
of the endosperm.

I. ARIS^EMA, Martius.

Perennial herbs, springing from a corm or a tuberous
rootstock.

Spathe rolled up at base. Summit of spadix naked, the
lower part flower-bearing ; staminate flowers above, pistil-
late ones below. Stigma flat ; ovary 1-celled ; berry 1-few-
seeded.

MONOCOTYLEDONOTJS PLANTS 25

1. A. triphyllum, Ton. INDIAN TURNIP, JACK-IN-THE-PULPIT.

Leaves generally 2, each of 3 elliptical-ovate, pointed leaflets. Spadix
club-shaped, bearing usually only one kind of fully developed flowers ;
that is, full-sized pistillate and rudimentary staminate ones, or the
reverse. Spathe much longer than the spadix, and covering it like
a hood. Corm turnip-like, but much wrinkled, very starchy, and
filled with intensely burning juice.

2. A. Dracontium, Schott. GREEN DRAGON, DRAGON ROOT. Leaf
usually single, divided into 7-11 rather narrow-pointed leaflets ;
spadix tapering to a long, slender point, often bearing fully devel-
oped staminate and pistillate flowers.

H. SYMPLOCARPUS, Salisb.

Kootstock very stout, with many long, cylindrical roots.
Leaves clustered, very large, and entire. Spathe shell-shaped,
very thick. Spadix globular, thickly covered with perfect
flowers. Sepals 4. Stamens 4. Style 4-angled. Fruit glob-
ular or ellipsoidal, with the seeds slightly buried in the
enlarged spadix.

Coarse, stemless herbs, with a powerful scent like that of
the skunk and of onions.

1. S. foetidus, Salisb. SKUNK CABBAGE. Leaves many, slightly
petioled, 1-2 ft. long, appearing after the flowers. The latter are
usually seen before the ground is wholly free from frost, often earlier
than any other flower. Bogs and wet meadows, very common N.

HI. ACORUS, L.

Rootstocks horizontal, long, and moderately stout, aromatic.
Leaves long, upright, sword-shaped. Spathe much like the
leaves. Spadix projecting from the edge of the spathe, con-
sisting of numerous perfect flowers. Sepals 6. Stamens 6.
Ovary 2-3-celled, with numerous ovules. Fruit 1-few-seeded.

1. A. Calamus, L. SWEET FLAG. Scape with a long, leaf-like
prolongation (spathe) beyond the green, very closely flowered, spadix.
Along borders of brooks and swamps.

The rootstocks furnish the well-known calamus or " sweet flag-
root " sold everywhere by druggists.

FOUNDATIONS OF BOTANY

7. COMMELINACE^. SpiDERWORT FAMILY.

Herbs, with slimy or mucilaginous juice ; stems somewhat
succulent, jointed, leafy, simple or branched. Leaves simple,
succulent, narrow, entire, sheathing at the base, sheaths entire

FIG. 5. — Acorus Calamus.
A, spadix ; B, a single flower, enlarged ; C, diagram of flower, enlarged.

or split. Flowers in terminal cymes or umbels, perfect, often
irregular. Sepals 3, persistent, foliaceous or colored. Petals 3,
soon falling or liquefying ; stamens 6 or fewer, often some of
them abortive. Ovary 2-3-celled ; style single, stigma entire
or 3-lobed, fruit a 2-3-celled, 2-3-valved capsule, seeds soli-
tary or several in each cell.*

MONOCOTYLEDONOUS PLANTS 27

I. COMMELINA, Dill.

Annual or perennial, stem branching, erect or procumbent,
smooth or downy. Leaves petioled or sessile, entire, the
floral ones heart-shaped, folded, and forming a spathe enclos-
ing the base of the cymes. Flowers irregular, sepals mostly
colored, 1 of them smaller. Petals blue, unequal, 2 of them
kidney-shaped and long-clawed, the other smaller. Stamens 6,
only 3 of them fertile, filaments smooth. Capsule 1-3-celled,
seeds 1-2 in each cell.*

1. C. virginica, L. VIRGINIA DAYFLOWER. Stem erect, downy,
1-2 ft. high. Leaves lanceolate to oblong-lanceolate, taper-pointed,
3-5 in. long, somewhat rough above, sheaths inflated, hairy,
the opening often fringed. Spathes containing a slimy secretion.
Flowers 1 in. wide, the odd petal lanceolate. Capsule 3-seeded, the
dorsal cell not splitting open. On moist, sandy soil.*

II. TRADESCANTIA, L.

Perennial, stem simple or branched. Leaves very narrow.
Flowers in terminal and axillary bracted umbels, regular,

1 in. broad. Sepals 3, herbaceous. Petals 3, soon falling or
liquefying to jelly. Stamens 6, sometimes 3 shorter than the
others, filaments bearded or smooth. Ovary 3-celled, with

2 ovules in each cell, pedicels recurved in fruit. Capsule
3-celled, 3-valved, 3-6-seeded.*

1. T. virginica, L. SPIDERWORT. Stem erect, stout, smooth,
or with long, soft hairs, 1-2 ft. high. Leaves linear, keeled, often
purple-veined, long, taper-pointed, 1 ft. or more in length. Bracts
similar to the leaves, umbels sessile, 2-many-flowered, flowers in 2
rows in the bud. Petals blue or purple, twice as long as the sepals.
Stamens blue, filaments densely bearded. Capsule ovoid or oblong.
On dry, sandy soil.*

2. T. pilosa, Lehm. HAIRY SPIDERWORT. Stem stout, erect, or
zigzag, branched, with long, soft hairs, or nearly smooth, 1-2 ft.
high. Leaves linear-oblong, taper-pointed at the apex, narrowed at
the base, hairy on both sides. Umbels axillary and terminal, many-
flowered. Pedicels and sepals with soft, glandular hairs. Flowers
blue or purple, |-1 in. wide. Seeds pitted. In rich soil,*

28 FOUNDATIONS OF BOTANY

HI. ZEBRINA.

Trailing or slightly climbing herbs. Leaves often striped.
Flowers irregular, usually in pairs. Calyx with a short tube,
regularly or irregularly 3-parted. Corolla nearly regular,
with tube longer than the calyx. Filaments naked or bearded.
Ovary 3-celled, 3-6-ovuled.

1. Z. pendula, Schnitzl. WANDERING JEW. Stems perennial,
prostrate, or nearly so, branching freely, rooting easily at the nodes.
Leaves somewhat succulent, lance-ovate or oblong, crimson beneath,
green or dark purplish above, often with two wide silvery stripes.
Cultivated from Mexico.

8. PONTEDERIACE^). PICKEREL-WEED FAMILY.

Perennial marsh or aquatic herbs, stems simple or branched,
succulent. Leaves simple, alternate. Flowers solitary or
spiked, each subtended by a leaf-like spathe, perfect, mostly
irregular. Perianth corolla-like, 6-parted. Stamens 3 or 6,
unequal, inserted irregularly in the tube or throat of the
perianth. Ovary free, style single, stigma entire or toothed,
ovary 1 or 3 celled. Fruit a 1-seeded utricle.*

PONTEDERIA, L.

Stem erect, from a thick, creeping rootstock, bearing a
single leaf above the middle and several sheathing, bract-like
leaves at its base. Eadical leaves numerous, thick, parallel-
veined. Petiole long, from a sheathing base. Flowers in
terminal spikes. Perianth 2-lipped, lobes of the upper lip
ovate, of the lower oblong, spreading. Stamens 6, the 3
upper short and often imperfect, the 3 lower protruding.
Ovary 3-celled, but only 1 cell ovule-bearing. The 1-seeded
utricle enclosed by the base of the perianth.*

1. P. cordata, L. PICKEREL-WEED. Stem stout, erect, 2—4 ft. high.
Leaves long, from heart-shaped to lanceolate and often halberd-
shaped, apex and basal lobes obtuse, finely nerved. Spike dense,

MONOCOTYLEDONOUS PLANTS 29

2-4 in. long, peduncles enclosed by the spathe. Perianth hairy,
blue, the upper lip with 2 yellow spots, tube 6-ribbed, curved, rather
longer than the lobes. Ovary oblong. In ponds and slow streams.*

9. JTJNCACE^. RUSH FAMILY.

Grass-like perennial or annual herbs, mostly growing on
wet soil. Stems mostly erect but sometimes creeping, simple
or branched, naked or leafy and jointed. Leaves cylindrical,
sheathing at the base, very slender and pointed or flattened
and grass-like. Flowers in cymes or panicles, which may be
very loose and spreading, or so compact as to form a head,
sometimes with a rigid scape prolonged beyond the flower-
cluster. Flowers usually bracted, perianth of 6 nearly equal
scale-like persistent divisions. Stamens 3 or 6, inserted on
the base of the perianth. Ovary free, 1 or 3 celled, many-
ovuled. Style single, stigmas 3, usually hairy. Fruit a 1 or
3 celled, 3-many-seeded capsule. [Most species flower late in
the season, and their identification is too difficult for one
without considerable experience.] *

10. LILIACE^. LILY FAMILY.

Mostly herbs. Flowers regular and symmetrical. Perianth
free from the ovary. Stamens nearly always 6, one before
each division of the perianth. Ovary usually 3-celled. Fruit
a pod or berry, few— many-seeded.

Except in the genus Trillium the divisions of the perianth
are colored nearly alike.

30 FOUNDATIONS OF BOTANY

SUBFAMILY I. — LILIACE JE PROPER.

Not tendril-climbers, rarely dioecious.

Styles or sessile stigmas 3, more or less separate.

Leaves 3-ranked, strongly nerved and plaited. Flowers some-
what monoecious, small. Veratrum, I.
Leaves flat, lanceolate, or spatulate. Flowers dioecious, showy.

Chamselirium, II.
Leaves grass-like. Flowers perfect, showy. Amianthium, III.

Style undivided (in No. XXIII, 3 sessile stigmas}. Plants from root-
stocks.

Leaves perfoliate. Flowers solitary, drooping, yellow.

Uvularia, IV.

Leaves broad, clasping. Flowers solitary or nearly so, drooping,

yellow. Oakesia, V.

Leaves scale-like. Thread-like branches borne in their axils.

Flowers small, bell-shaped. Asparagus, XVII.

Leaves several-many, sessile or clasping, alternate. Flowers

small, 6-parted, white, in a terminal simple or compound

raceme. Smilacina, XVIII.

.Leaves only 2-3, sessile or slightly petioled. Flowers very

small, 4-parted, solitary or in a small terminal cluster.

Maianthemum, XIX.

Leaves clasping. Flowers solitary or in pairs, greenish-white or
rose-purple, borne on pedicels abruptly bent near the middle.

Streptopus, XX.

Leaves nearly sessile or partly clasping. Flowers axillary,
greenish, on pedicels jointed near the flower.

Polygonatum, XXI.

MONOCOTYLEDONOUS PLANTS 31

Leaves only 2, directly from the rootstock. Flowers in a raceme,
bell-shaped, white, sweet-scented. Convallaria, XXII.

Leaves 3, netted-veined. Flower single, large, terminal.

Trillium, XXIII.

Style undivided. Plants from fibrous roots.

Flowers yellow or orange. Hemerocallis, VI.

Flowers white. Yucca, XVI.

Style usually undivided. Plants from coated or solid-looking bulbs.

Leafy-stemmed plants. Flowers large, solitary, or apparently
umbelled. Fritillaria, IX.

Apparently stemless plants.

(a) Plants with the smell of onions or garlic. Flowers

umbelled. Allium, VII.

(&) Flower solitary, erect, l^rge. Tulipa, X.

(rf) Flowers racemed. Perianth with hardly any tube.

Stigma a single knob. Scilla, XII.

(e) Flowers racemed. Perianth with hardly any tube.

Stigma 3-cleft. Camassia, XIII.

(f) Flowers corymbed. Perianth with hardly any tube.

Leaves linear. Ornithogalum, XIV.

(</) Flowers racemed. Perianth with a tube. Leaves

lance-linear. Hyacinthus, XV.

Style undivided. Plants from scaly bulbs. Lilium, VIII.

SUBFAMILY II. — SMILACE^E.

Climbers, often tendril-bearing. Flowers dioecious. Smilax, XXIV.

32 FOUNDATIONS OF BOTANY

I. VERATRUM, Tourn.

Simple-stemmed perennials. Koots fibrous, from the thick-
ened base of the stem, poisonous, emetic. Leaves 3-ranked,
plaited, and veiny. Flowers panicled, greenish, or brownish.
Sepals 6, spreading, nearly free from the ovary. Stamens
shorter than the perianth, and inserted on its base. Ovary of
3 carpels united at base. Fruit a few-seeded capsule, splitting
into 3 parts.

1. V. viride, Ait. WHITE HELLEBORE. INDIAN POKE. Stem
stout, 2—7 ft. high, very leafy. Flowers very numerous, in a panicle,
composed of spike-like racemes. Sepals yellowish-green. Wet
meadows and brooksides.

2. V. Woodii, Robbins. Stem slender, 2-5 ft. high, not very leafy.
Flowers in a long, narrow panicle. Sepals greenish-purple or almost
black. Woods and dry hillsides.

II. CHAMJELIRIUM, Willd.

Rootstock short and thick, bitter. Stem simple, erect, leafy,
smooth. Lower leaves spatulate to obovate, the stem-leaves
narrower. Flowers small, white, in a spike-like raceme,
dio?cious. Perianth of 6 linear-spatulate segments. Stamens
6, filaments longer than the perianth. Ovary 3-celled, styles
3. Fruit an ovoid, 3-angled, many-seeded capsule.*

1. C. carolinianum, Willd. UNICORN-ROOT, DEVIL'S BIT. Stem
furrowed, staminate plants 1-2 ft. high, pistillate taller, often 3 ft.
or more. Lower leaves obovate, clustered, the upper small and
bract-like. Staminate racemes slender and drooping, the pistillate
erect. Flowers short-pediceled. Capsule 3-valved, seeds linear-
oblong, winged at the ends. On low ground.*

III. AMIANTHIUM, Gray.

Stem simple, glabrous, erect from a bulbous base. Leaves
long and slender. Flowers white, in a simple terminal raceme,
perfect. Perianth of 6 segments which are sessile and gland-
less. Stamens 6, inserted in the base of the perianth. Ovary
3-lobed, 3-celled, fruit a dehiscent, 3-lobed capsule, the lobes
becoming awl-shaped by the persistent style bases ; cells few-
seeded.*

MONOCOTYLEDONOUS PLANTS 33

1. A. muscaetoxicum, Gray. FLY POISON. Bulb ovoid or oblong.
Stem somewhat angled below, 1-3 ft. high. Lower leaves strap-
shaped, channeled, the upper small and bract-like. Raceme dense,
cylindrical, pedicels from the axils of minute ovate bracts. Peri-
anth segments ovate, white, becoming greenish, nearly as long as
the slender stamens. Styles spreading. Capsule with divergent
lobes; seeds ovoid, red. In rich woods.*

IV. UVULARIA, L.

Bather low plants with short rootstocks. Leaves alternate,
broad, and parallel-veined. Flowers yellow or yellowish,
drooping, borne singly at the' end of the forking stem.
Perianth of 6 similar and separate narrow spatulate sepals,
each grooved and nectar-bearing inside toward the base.
Stamens 6, with linear anthers, which are much longer than
the filaments. Style 3-cleft. Pod 3-lobed, 3-celled, few-
seeded.

1 . U. grandiflora. LARGER BELLWORT. Leaves oblong, with the
base clasping the stem so as to make it appear to run through the
leaf a little way from the base ; flowers greenish- yellow, l£ in. long,
anthers obtuse. A leafy plant, 1-2 ft. high.

2. U. perfoliata. MEALY BELLWORT. Leaves much as in the
preceding species ; flowers very pale yellow, with shining grains on
the inner surfaces of the twisted sepals; anthers sharp-pointed;
plant about % the size of the preceding.

V. OAKESIA, Watson.

Plants with much the aspect of the preceding genus, but
with merely sessile leaves, triangular winged pods, and slen-
der creeping rootstocks.

1. 0. sessilifolia. WILD OATS, STRAW LILIES. Stem slender,
zigzag. Leaves lance-oval, thin, smooth, pale beneath, 1-1 £ in.
long. Flower cream-color, nearly 1 in. long.

VI. HEMEROCALLIS, L.

Perennial, from a fascicle of fleshy roots. Stem erect,
branched, smooth. Leaves mostly basal and linear. Flowers
on branching scapes, large, yellow or orange, solitary or

34 FOUNDATIONS OF BOTANY

corymbed, perianth funnel-form, with a spreading limb much
longer than the tube. Stamens 6, inserted in the top of the
tube, shorter than the lobes, curved upward. Ovary 3-celled,
many-ovuled, style longer than the stamens, curved upward,
stigma knobbed. Fruit a 3-celled, 3-angled capsule.*

1. H. fulva, L. DAY LILY. Scapes stout, branched above, with a
few bract-like leaves, smooth, 3-5 ft. high. Leaves very long, strap-
shaped, acute, channeled. Flowers short-pediceled, tawny-yellow,
perianth lobes oblong, netted-veined, lasting only one day. Intro-
duced from Asia and common in old gardens.*

VH. ALLIUM, L.

Stemless herbs from coated bulbs with the characteristic
odor of onions. Bulbs solitary or clustered. Leaves narrowly
linear or slender-tubular, with a bloom. Flowers small on
slender pedicels, in terminal umbels on naked scapes, the
umbels often bracted or enclosed in a spathe. Perianth
6-parted, persistent ; stamens 6, inserted on the base of the
perianth, filaments filiform or dilated below. Ovary sessile,
3-celled. Style thread-like, jointed ; stigma entire. Fruit a
3-celled, 3-valved, few-seeded capsule. Flowers sometimes
changed into bulblets.*

1. A. canadense, L. MEADOW GARLIC. Bulbs ovoid, the outer
coats of white and thin, dry, netted fibers. Leaves narrowly linear,
flat, or concave above. Scape cylindrical, 1 ft. high. Bracts of the
umbel 2-3, ovate, acuminate ; umbel consisting mostly of sessile
bulblets. The few flowers long-pediceled, rose-colored. Perianth
about as long as the stamens. Filaments dilated below. Capsule
shorter than the perianth, 6-toothed, ovules 2 in each cell. On moist
soil.*

2. A. striatum, Jacq. STRIPED WILD ONION. Bulbs clustered,
outer coat membranaceous. Leaves linear, concave, striate on the
back. Scape 6-12 in. high. Umbel 3— 10-flowered, bracts 2, pedicels
1-2 in. long. Perianth nearly white, longer than the stamens, the
outer segments green-keeled on the back. Capsule not toothed,
seeds several in each cell. Low pine barrens.*

• 3. A. vineale, L. FIELD GARLIC. Bulb mostly solitary. Leaves
cylindrical, hollow, very slender. Scape slender, sheathed below the
middle by the bases of the leaves. Umbels often crowded with
bulblets. A troublesome weed in moist meadows and fields east-
ward, giving milk a strong flavor of onions or garlic.

MONOCOTYLEDONOUS PLANTS 35

VIII. LILIUM, L.

Perennial, from scaly bulbs, stem erect, leafy, usually tall
and slender. Leaves sessile, scattered, or whorled. Flowers
large, erect, or drooping. Perianth corolla-like, deciduous.
Segments 6, spreading or recurved above, sessile or clawed,
each with a nectar-bearing groove near the base. Stamens 6,
elongated, anthers linear, versatile. Ovary 3-celled, many-
ovuled, style long and slender, stigma 3-lobed. Fruit a 3-celled,
dehiscent, many-seeded capsule.

1. L. longiflorum, Thunb. LONG-FLOWERED WHITE LILY. Stem
1-3 ft. high. Leaves thick, lanceolate, scattered. Flower single,
pure white, funnel-shaped, 5-6 in. long. Var. eximium, the Easter
lily, bears several very showy and sweet-scented flowers.

2. L. philadelphicum, L. WILD RED LILY. Stem 2-3 ft. high.
Leaves linear-lanceolate, the upper ones generally whorled. Flower
usually solitary (sometimes 2 or 3), erect, reddish-orange, with tawny
or purplish spots inside. Sepals with claws. Dry or sandy ground,
borders of thickets, etc.

3. L. canadense, L. WILD YELLOW LILY, MEADOW LILY. Stem
2-5 ft. high. Leaves lanceolate, 3-nerved, the margins and nerves
roughish with short hairs, whorled. Flowers usually 3, sometimes
more numerous, all nodding, on peduncles 3-6 in. long, yellow or
orange, with dark-purple or brown spots inside. Sepals without
claws, recurved. Moist meadows and borders of woods.

IX. FRITILLARIA, Tourn.

Leafy-stemmed perennials, from scaly or coated bulbs.
Flowers single or several, nodding. Perianth bell-shaped, a
nectar-bearing spot above the base of each division. Stamens
as long as the petals.

1. F. Meleagris, L. GUINEA-HEN FLOWER. Stem 1 ft. high.
Leaves linear, alternate, channeled. Flower usually single, large,
purplish, checkered with blue and purple or yellow. Cultivated
from Europe.

2. F. imperialis, L. CROWN IMPERIAL. Stem 3-4 ft. high. Leaves
abundant in whorls about the middle or lower part of the stem, lan-
ceolate or lance-oblong. Flowers several, large, yellow or red, in an
umbel-like cluster beneath the terminal crown of leaves. Cultivated
from Asia.

36 FOUNDATIONS OF BOTANY

X. TULIPA, Tourn.

Stemless herbs from coated bulbs. Leaves sessile. Scape
simple. Flower solitary, erect. Perianth bell-shaped. Stamens
short, awl-shaped, with broadly linear anthers. Style short,
stigma thick, 3-lobed. Ovary and pod triangular.

1. T. gesneriana, L. COMMON TULIP. Leaves 3-6, ovate-lanceo-
late, close to, the ground. Flower large, on a smooth peduncle, color
red, yellow, white, or variegated. Cultivated from Asia Minor.
Many garden varieties exist.

XI. ERYTHRONIUM, L.

Nearly stemless herbs, arising from rather deeply buried
bulbs. Leaves 2, long and smooth, with underground petioles.
Scape arising from between the bases of the leaves. Flower
commonly single, nodding.

1. E. americanum, Ker. YELLOW ADDER'S-TONGUE. Leaves
mottled. Flowers handsome. Perianth light yellow, style club-
shaped, stigmas united.

2. E. albidum, Nutt. WHITE DOG'S-TOOTH VIOLET. Leaves
not much mottled. Perianth bluish-white. Stigmas 3, short and
spreading.

XH. SCILLA, L.

Perennial stemless herbs from coated bulbs. Leaves linear.
Flowers racemed on a scape, generally blue. Divisions of the
perianth 1-nerved, parted almost to the base. Filaments 6,
often broad at the base. Style slender, with a knob-like
stigma. Ovary 3-angled, 3-celled.

1. S. sibirica, Andr. SIBERIAN SQUILL. Scapes 3-8 in. high,
several from each bulb, 2-3-flowered. Leaves 2-4, narrowly strap-
shaped. Flowers intense blue, short-peduncled, often nodding.
Cultivated from Russia and Siberia. •

XIII. CAMASSIA, Lindl.

Stemless herbs, from coated bulbs. Leaves linear. Flowers
racemed, on a scape. Perianth of 6 blue or purple spreading
sepals. Stamens with thread-like filaments, from the base of
the perianth. Style thread-like, ending in a knobbed stigma.
Capsule 3-angled, 3-celled, several-seeded.

MONOCOTYLEDONOUS PLANTS 37

1. C. Fraseri, Torr. WILD HYACINTH. Leaves keeled, weak,
shorter than the scape. Flowers in a long-bracted raceme, pale
blue. River bottoms and other damp, rich soil.

XTV. ORNITHOGALUM, Tourn.

Stemless herbs from coated bulbs. Leaves linear, fleshy.
Scape erect. Flowers in corymbs or racemes, bracted. Peri-
anth .segments 6, white, nerved, persistent. Stamens 6,
hypogynous, slender. Filaments flattened. Ovary sessile,
3-celled, few-ovuled. Fruit a roundish, 3-angled capsule,
seeds black.*

1. 0. umbellatum, L. STAR OF BETHLEHEM. Bulb ovoid, mem-
branous-coated. Leaves numerous, linear, fleshy, mid-vein nearly
white, as long as the scape. Scape slender, 6-12 in. high. Flowers
opening in sunshine, long-pediceled. Bracts linear-lanceolate, about
as long as the pedicels. Perianth segments oblong-lanceolate, white
with a green stripe on the back, twice the length of the stamens.
Introduced from Europe ; very common about old gardens.*

XV. HYACINTHUS, L.

Stemless herbs from coated bulbs. Leaves linear, fleshy.
Flowers in an erect spike, pediceled, bracted. Perianth
tubular below, lobed and spreading above. Stamens short,
included. Style short, stigma knobbed. Ovary 3-celled,
rnany-ovuled.*

1. H. orientalis, L. HYACINTH. Leaves lance-linear, thick and
fleshy, smooth. Scape erect, many-flowered. Segments united about
half their length, white, blue, or red. Filaments very short. Ovary
rarely maturing seed. Common in cultivation.*

XVI. YUCCA, L.

Plants with woody and leafy stems. Leaves numerous,
rigid, spine-pointed, persistent. Flowers in large terminal
racemes or panicles, bracted, nodding. Perianth bell-shaped,
segments 6, nearly alike, deciduous. Stamens 6, filaments
thickened above, often papillose. Anthers small. Ovary
sessile, 3-celled, or becoming 6-celled, 3-angled, many-ovuled.
Fruit an oblong, 3-angled, many-seeded, dehiscent capsule,
or fleshy and indehiscent.*

38 FOUNDATIONS OF BOTANY

1. Y. filamentosa, L. SPANISH DAGGER. Stem stout, 4-12 in.
high. Leaves linear or linear-lanceolate, slender-pointed, narrowed
above the spreading and clasping base, spreading or recurved, smooth,
with loose, thread-like filaments on the margins. Panicle elongated,
with bract-like leaves on the scape, widely branched, downy-hairy
above, 3-6 ft. high. Perianth white, bell-shaped, 2 in. wide. Cap-
sule oblong, angles rounded, sides furrowed, at length 3-valved and
dehiscent. In sandy soil, and often cultivated for ornament.*

XVII. ASPARAGUS, Tourn.

Stem from fleshy fibrous roots, erect, branched, branches
slender, with thread-like branchlets in the axils of scales which
take the place of leaves. Flowers small, solitary, or racemed.
Perianth 6-parted, segments distinct or slightly united. Sta-
mens 6, perigynous, filaments thread-like. Ovary 3-celled,
6-ovuled, style short, slender, stigmas 3, recurved. Fruit a
berry.*

1. A. officinalis, L. ASPARAGUS. Stem succulent and simple, with
fleshy scales when young, becoming taller, more woody and widely
branched when old. Flowers axillary, solitary, or 2 or 3 together on
slender, jointed, drooping pedicels, greenish, segments linear. Berry
red, few-seeded. Introduced from Europe, common in cultivation,
and often escaped.*

XVm. SMILACINA, Desf.

Perennial, simple-stemmed herbs, with rootstocks. Leaves
usually sessile, nerved, alternate. Flowers white, in a ter-
minal raceme. Perianth spreading, 6-parted. Stamens 6,
springing from the base of the perianth. Filaments slender.
Anthers short, facing inward. Ovary 3-celled, 6-ovuled. Style
short and stout, with a somewhat 3-lobed stigma. Fruit a
1-2-seeded berry.

1. S. racemosa, Desf. FALSE SPIKENARD. A showy plant with
curved stem 1-3 ft. high, downy throughout. Leaves abundant,
oval or ovate-lanceolate, taper-pointed. Flowers small, in a com-
pound raceme. Berries pale red, speckled with dark red or purple.
Moist thickets.

2. S. stellata, Desf. Plant 1 ft. or less in height, nearly smooth.
Leaves broadly lanceolate, acute, clasping. Flowers few, larger than
in No. 1, in a simple raceme. Berries very dark red. Along river
banks.

MONOCOTYLEDONOUS PLANTS 39

XIX. MAIANTHEMUM, Wigg.

Stem low. Leaves 2-3, lanceolate or ovate, with a heart-
shaped base. Flowers small, white, solitary, or in a simple
raceme. Perianth 4-parted. Stamens 4. Ovary 2-celled.
Stigma 2-lobed.

1. M. canadense, Desf. TWO-LEAVED SOLOMON'S SEAL, WILD
LILY-OF-THE-VALLEY. Plant 3-6 in. high. Leaves very short-
petioled. Fruit a globular or ovoid berry, whitish, with brownish-
red blotches. Woods and shaded banks N.

XX. STREPTOPUS, Michx.

Herbs with forking stems from a creeping rootstock. Leaves
clasping. Flowers small, borne singly or in pairs on peduncles
which arise above the leaf-axils and which are sharply bent
or twisted near the middle. Anthers arrow-shaped. Ovary
3-celled, ripening into a red, many-seeded berry.

1. S. amplexifolius, D. C. LIVER-BERRY. Stem smooth, 2 ft. or
more high. Leaves smooth-margined. Flowers greenish-white.
Damp woods.

2. S. roseus, Michx. LIVER-BERRY, JACOB'S LADDER. Branches
with a few bristly hairs. Lower leaves margined with fine bristles.
Flowe'rs reddish or purplish. Cold, damp woods N.

XXI. POLYGONATUM, Tourn.

Rootstock creeping, jointed, scarred. Stems simple, erect,
scaly below, leafy above. Leaves alternate, oval, or oblong.
Flowers on axillary, 1-4-flowered, drooping, jointed peduncles.
Perianth tubular, 6-cleft. Stamens 6, included, inserted about
the middle of the tube. Anthers arrow-shaped. Ovary
3-celled, many-ovuled, style slender, stigmas knobbed or
3-lobed. Fruit a few-seeded berry.*

1. P. biflorum, Ell. HAIRY SOLOMON'S SEAL. Stem simple, erect,
arched, nearly naked below, 1-2 ft. high. Leaves 2-ranked, sessile
or clasping, 3-7-nerved, smooth above, pale and downy beneath.
Peduncles short, 1-4, often 2-flowered. Perianth greenish, 1-2 in.
long. Filaments thread-shaped, roughened. Berry dark blue.
Shady banks.*

40 FOUNDATIONS OF BOTANY

2. P. giganteum, Dietrich. SMOOTH SOLOMON'S SEAL. Stem
simple, stout, curving above, 3-8 ft. high. Leaves lanceolate to ovate,
many-nerved, partly clasping, smooth on both sides. Peduncles nearly
half as long as the leaves, 2-6-flowered. Perianth green ish-yellow,
| in. long. Filaments smooth. Berry blue, \ in. in diameter. In
rocky woods and along streams.*

XXII. CONVALLARIA, L.

Low, smooth, stemless, perennial herbs. Leaves 2, oblong,
with long petioles, from a slender, creeping rootstock. Scape
slender, angled, enclosed at the base by the leaf-stalks. Flowers
racemed, white, drooping. Perianth bell-shaped, with recurved
lobes. Stamens borne on the base of the perianth. Ovary
3-celled, ripening into a few-seeded red berry.

1. C. majalis, L. LILY-OF-THE-VALLEY. A familiar garden flower,
cultivated from Europe, and also found wild in mountain woods
from Virginia to Georgia.

XXIH. TRILLIUM, L.

Low herbs with the stem springing from a short rootstock.
Leaves 3, large, netted-veined, in a whorl. Flower large, ter-
minal. Perianth of 6 parts, the 3 sepals unlike the 3 petals
in color and in texture. Stamens 6, with the linear anthers
usually opening inward, longer than the filaments. Stigmas
3, sessile, spreading at the tips. Ovary 3 or 6-angled, 3-celled,
many-seeded. Fruit a roundish, many-seeded purple berry.

1. T. sessile, L. Rootstock erect or ascending, corm-like. Stem
slender, 1-8 in. high. Leaves broadly oval, obtuse or acute at the
apex, rounded and sessile at the base, 3-5-nerved, smooth, bright
green, not mottled. Flowers sessile, sepals lanceolate, f-1 in. long,
petals purple, elliptical, about the length of the sepals. Stamens
half the length of the petals. Styles elongated, straight. In rich
woods.*

2. T. Underwoodii, Small. UNDERWOOD'S WAKE-ROBIN. Root-
stock horizontal, stem stout, 4—12 in. high. Leaves ovate-lanceolate
to broadly ovate, acute or short taper-pointed at the apex, rounded
and sessile at the base, wavy on the margins, 3-5-nerved, smooth,
prominently mottled with different shades of green. Flowers sessile.
Sepals lanceolate, l£-2 in. long, often purplish green. Petals purple,
lanceolate to oblanceolate, 2-3 in. long. Stamens \-\ the length
of the petals. Style very short, stigmas recurved, Fruit an ovoid
berry. In rich woods,*

MONOCOTYLEDONOUS PLANTS 41

3. T. erectum, L. SQUAWROOT, BENJAMIN. Rootstock rather
upright, large and stout. Leaves broadly diamond-shaped, tapering
to a short point. Pedicel 1-3 in. long, not quite erect. Petals ovate
to lanceolate, much broader than the sepals, of a rich brownish-
purple or sometimes white or pale. Stigmas distinct, stout, and
spreading. The disagreeable scent of the flower has given rise to
several absurd popular names for it. In rich woods.

4. T. grandiflorum, Salisb. LARGE-FLOWERED WAKE-ROBIN.
Rootstock horizontal, stem slender, 12-18 in. high. Leaves rhombic-
ovate, taper-pointed at the apex, rounded and sessile or slightly
peduncled at the base, smooth and with a bloom, 5-7-nerved, bright
green. Peduncle longer than the erect or slightly declined flower.
Sepals lanceolate-acute, 1-1^ in. long. Petals white, fading to pink,
longer than the sepals. Stamens less than half the length of the
petals. Style short, stigmas recurved. Fruit a black, roundish berry.
In rich woods.*

5. T. nivale, Riddell. DWARF WHITE TRILLIUM. Plant 2-4 in.
high. Leaves petioled, oval to ovate. Flower white, erect. Petals
^-1^ in. long, ovate-spatulate. Rich, damp woods, blooming with
the very earliest spring flowers.

6. T. erythrocarpum, Michx. PAINTED TRILLIUM. Plant 8-12
in. high. Roofstock oblique to the rest of the stem, rather small ;
roots long and fibrous. Leaves ovate, taper-pointed. Petals white,
penciled at the base, with purple stripes, lance-ovate, somewhat
recurved, wavy. Cold woods, especially N.

XXIV. SMILAX, Tourn.

Mostly woody vines, usually with prickly steins, climbing by
tendrils. Rootstock often large and tuberous. Leaves alter-
nate, prominently nerved, netted-veined, petioled, stipules
replaced by persistent tendrils. Flowers regular, dioecious,
small, greenish, in axillary umbels. Perianth bell-shaped,
segments 6. Stamens 6, distinct. Ovary 3-celled, 3-6-ovuled,
stigmas 1-3, sessile or nearly so. Fruit a 1-6-seeded globose
berry.

1. S. herbacea, L. CARRION-FLOWER. Stem herbaceous, erect,
simple or branched, not prickly, 1-3 ft. high. Leaves few, ovate,
acute, and mucronate at the apex, somewhat heart-shaped at the
base, 5-7-nerved, thin, smooth above, downy below, the upper some-
times whorled and the lower bract-like ; petiole short. Peduncles as
long as the leaves, growing from below the petiole. Umbel many-
flowered, flowers carrion-scented. Berry blue-black, 2-4-seeded. Dry,
fertile soil.*

42 FOUNDATIONS OF BOTANY

2. S. glauca, Walt. GREEN-BRIER. Stem cylindrical, slender,
with scattered prickles, branches angled, and usually without prickles.
Leaves ovate or subcordate, pointed at the apex, mostly 5-nerved,
smooth, white beneath, with a bloom, margin entire. Peduncle
flattened, 2-3 times as long as the petiole, few-flowered. Berry
black, 3-seeded. Margin of swamps.*

3. S. Bona-Nox, L. BAM BOO- VINE. Stem stout, cylindrical, or
slightly angled, scurfy when young, armed with numerous stout
prickles. Branches 4-angled, usually unarmed. Leaves triangular,
ovate, or often halberd-shaped, 5-7 -ribbed, smooth on both sides and
often discolored, margins usually fringed with fine prickles. Pedun-
cles twice as long as the petioles, flattened. Umbels many-flowered,
pedicels short. Berries 8-20 in a cluster, black, 1-seeded. In swamps
and thickets.*

4. S. Walteri, Pursh. GREEN-BRIER. Stem low, with few
prickles, 2-5 ft. long, branches slightly 4-angled, unarmed. Leaves
oblong-lanceolate to oval, obtuse or acute at the apex, rounded or
cordate at the base, 5-ribbed, smooth. Peduncles flattened, about as
long as the petioles and pedicels. Berry bright red, ripening the
first year. Wet pine barrens.*

5. S. rotundifolia, L. GREEN-BRIER, CAT-BRIER, DOG-BRIER,
HORSE-BRIER, WAIT-A-BIT. Stem green, strong ; branchlets, and
sometimes the branches, 4-angled, armed with stout hooked prickles.
Leaves ovate or round-ovate, with a slightly heart-shaped base and
an abruptly pointed tip. Berries black, with a bloom. Thickets,
the commonest species N. E.

11. AMARYLLIDACEJE. AMARYLLIS FAMILY.

Mostly smooth perennial herbs, from bulbs. Leaves radi-
cal, with no distinction between petiole and blade. Flowers
borne on a scape, nearly or quite regular. Stamens 6.
Style 1. Tube of the 6-parted, corolla-like perianth adnate
to the 3-celled ovary. Capsule 3-celled, several-many-seeded.

I. ZEPHYRANTHES, Herb.

Stemless, from a coated bulb. Leaves linear, fleshy. Scape
erect, 1-few-flowered. Flowers large, erect, or declined, sub-
tended by a 1-2-leaved spathe. Perianth 6-parted, naked in
the throat, tube short, segments petal-like, spreading. Stamens
free, anthers versatile. Ovary 3-celled, many-ovuled. Style

MONOCOTYLEDONOUS PLANTS 43

elongated, declined. Stigma 3-cleft. Fruit a many-seeded,
3-valved capsule, seeds black, compressed, or angled.*

1. Z. Atamasco, Herb. ATAMASCO LILY. Bulbs about 1 in. in
diameter. Leaves narrow, concave above, smooth, usually longer
than the scape. Scape 6-12 in. high, 1-flowered. Spathe 1-leaved,
2-cleft. Flowers 2—3 in. long, white, tinged with pink or purple,
bell-shaped, short-peduncled. Stamens longer than the tube, shorter
than the style. Capsule depressed-globose, seeds angled. In rich,
damp soil, often cultivated.*

II. NARCISSUS, L.

Scapes with 1-several flowers from a thin, dry spathe.
Flowers with a cup-shaped or other crown on the throat of
the perianth ; tube of the perianth somewhat cylindrical, the
6 divisions of the limb widely spreading. Stamens 6, inserted
in the tube.

1. N. Pseudo-narcissus, L. DAFFODIL, DAFFY, EASTER-FLOWER.
Scape short, bearing 1 large yellow flower ; tube of perianth short
and wide, crown with a crimped margin. Cultivated from Europe.

2. N. Tazetta, var. orientalis. CHINESE SACRED LILY. Bulb
large, often with many smaller ones attached to its base. Scape
1 ft. or more high. Flowers several, umbeled, fragrant. Perianth
white or nearly so, the crown rather spreading, finely scalloped,
yellow or orange. Cultivated from China.

3. N. poeticus, L. POET'S NARCISSUS. Scape 1-flowered. Peri-
anth pure white, the crown very narrow, edged with pink. Culti-
vated from S. Europe.

III. HYPOXIS, L.

Small, stemless herbs. Leaves grass-like, hairy, from
a solid bulb. Scapes thread-like, few-flowered. Perianth
6-parted, wheel-shaped, the 3 outer divisions greenish on the
outside, the whole perianth withering on the pod. Seeds
numerous.

1. H. erecta, L. STAR-GRASS. Leaves longer than the scape,
both sparsely set with long, soft hairs. Scape 3-8 in. high. Flowers
1-4, about ^ in. across, yellow. Common in meadows and dry
woods.

FOUNDATIONS OF BOTANY

I, flower ; II, seed, longitudinal section ; III, flower with outer segments of
perianth removed ; stlg., stigma, ov., ovary-

FIG. 7. — Iris.

I, flower, longitudinal section, ov., ovary ; II, diagram, showing stigmas
ppposite the stamens ; III, capsule, splitting between the partitions.

MONOCOTYLEDONOUS PLANTS 45

12. IRIDACEJE. IRIS FAMILY.

Perennial herbs from bulbs, corms, or rootstocks. Leaves
2-ranked, equitant. Flowers perfect, regular or irregular, each
subtended by two bracts. Perianth 6-parted, the tube adher-
ent to the ovary, the segments in 2 series of 3 each, equal, or
the inner ones smaller. Stamens 3, distinct or united, oppo-
site the outer segments. Ovary forming a 3-celled, 3-angled,
3-valved, many-seeded, dehiscent capsule.*

I. CROCUS, L. Crocus.

Leaves radical. Flowers sessile on the corm. Tube of the
perianth very long and slender, its divisions all alike or
nearly so. Stigmas 3-cleft.

1. C. vernus. SPRING CROCUS. Leaves linear. Stigmas short.
Flowers white, blue, or purple. Our earliest garden flower. Culti-
vated from Europe.

H. IRIS, Tourn.

Rootstock thick, creeping, branching, horizontal, sometimes
tuberous. Stems erect, simple, or branched. Leaves linear or
sword-shaped. Flowers showy, epigynous, the outer perianth
segments spreading or recurved, often bearded within, the
inner segments usually smaller and erect. Stamens inserted
in the base of the outer segments. Style deeply 3-parted, the
divisions broad and petal-like, covering the stamens. Fruit
an oblong or oval, 3 or 6 angled, many-seeded capsule.*

1. I. versicolor, L. LARGE BLUE FLAG. Rootstock thick, hori-
zontal. Stem cylindrical, smooth, simple or branched, leafy, 2-3 ft.
high. Leaves linear, sword-shaped, finely nerved, with a bloom, the
lower l£-2 ft. long, the upper snorter. Bracts longer than the
pedicels. Flowers terminal, single, or few together, blue variegated
with white, yellow, and purple, perianth segments not bearded,
the inner ones smaller. Ovary 3-angled, longer than the inflated
perianth tube. Capsule oblong, slightly lobed, seeds 2 rows in each
cell. In wet places.*

2. I. germanica, L. FLEUR-DE-LIS. Rootstock thick, matted.
Stem stout, branched, leafy, 2-3 ft. high. Leaves strap-shaped,

46 FOUNDATIONS OF BOTANY

acute, erect, shorter than the stem, bracts scarious. Flowers sessile,
large and showy, blue, variegated with white and yellow, sometimes
nearly all white, outer segments large, recurved, bearded, the inner
narrower, erect, or arched inward. Introduced from Europe ; com-
mon in gardens and naturalized in many places.*

3. I. fulva, Ker. YELLOW FLAG. Rootstock fleshy. Stem sim-
ple or branched, grooved, 1-angled below, bearing 2-3 leaves, 2-3 ft.
high. Leaves linear, sword-shaped, with a bloom, shorter than the
stem, bracts small. Pedicels short, flowers axillary and terminal,
dull yellow or reddish-brown, variegated with blue and green, peri-
anth segments not bearded. Style branches but little exceeding
the stamens, ovary about as long as the inflated perianth tube.
Capsule ovate, 6-angled. Swamps and wet places.*

HI. SISYRHINCHIUM, L.

Small, grass-like perennials. Stems erect, flattened, or
winged. Boots fibrous. Leaves linear or lanceolate. Flowers
small, blue, quickly withering, in terminal 2-bracted umbels.
Perianth, corolla-like, of 6 bristle-pointed segments, tube
nearly or wholly lacking. Stamens 3, completely rnonadel-
phous. Stigmas 3, thread-like. Fruit a nearly globular
3-angled capsule. Species too difficult for the beginner.

13. ORCHIDACEJE. ORCHIS FAMILY.

Perennial herbs with simple stems, often arising from bulbs
or tubers. Leaves simple, usually alternate and entire. Flow-
ers perfect, generally showy, often extraordinarily irregular.
Perianth of 6 divisions, adnate to the 1-celled ovary. Stamens
1 or 2, united with the pistil ; pollen of comparatively few
grains held together in masses by cobweb-like threads. Ovary
1-celled, containing many (sometimes more than a million)
very minute ovules.

The family is a difficult one, and most of the genera are
so rare that specimens should not be collected in large num-
bers for class study. Two of the most familiar genera are
Cypripedium, or lady's slipper, and Spiranthes, or lady's tresses.
Many of the genera are tropical air-plants like Part I, Fig. 13.

DICOTYLEDONOUS PLANTS 47

SUBCLASS II. — DICOTYLEDONOUS PLANTS.

Stems composed of .bark, wood, and pith ; the fibro-vasciilar
bundles in rings ; in. woody stems which live over from year
to year, the wood generally in annual rings, traversed at right
angles by medullary rays. Leaves netted-veined. Parts of
the flower usually in fours or fives. Cotyledons 2 (rarely
none).

14. SALICACEJE. WILLOW FAMILY.

Dioecious trees or shrubs, with flowers in catkins (Ch. XIII),
destitute of floral envelopes. Fruit a 1-celled pod, with
numerous seeds, provided with rather long and silky down,
by means of which they are transported by the wind.

I. POPULUS, Tourn.

Trees with prominent scaly buds, twigs more or less angled.
Leaves usually long-petioled.

Flowers borne in long, drooping catkins, which appear
before the leaves ; scales of the catkins irregularly cut toward
the tip. Stamens 8-30 or more. Stigmas 2-4. Capsules
opening early by 2 to 4 valves.

1. P. tremuloides, Michx. AMERICAN ASPEN, QUAKING ASP. A

tree 20 to 60 ft. high, with greenish-white bark ; leaves roundish,
heart-shaped, abruptly pointed, with small regiilar teeth. Leaf-
stalk long, slender, and flattened at right angles to the broad
surfaces of the leaf, causing it to sway edgewise with the least per-
ceptible breeze. Common especially N.

2. P. grandidentata, Michx. LARGE-TOOTHED POPLAR. A tree
60 to 80 ft. high, with rather smooth gray bark ; leaves 3-5 in. long,
roundish ovate and irregularly sinuate-toothed; when young com-
pletely covered with white silky wool, which is shed as soon as the
leaf matures. The petiole is somewhat flattened, but not nearly as
much so as that of the preceding species. Rich woods K.

3. P. heterophylla, L. SWAMP POPLAR. Branches only slightly
angled. Leaves ovate, mostly obtuse at the apex, rounded or sub-
cordate at the base, serrate with obtuse teeth, densely woolly when

48 FOUNDATIONS OF BOTANY

young, but becoming smooth with age ; petioles cylindrical. Pistil-
late catkins smooth, erect, or spreading, loosely flowered. Capsule
ovoid, usually shorter than the pedicel. Common in river swamps.
A large tree with soft light wood, which is often used in making-
cheap furniture.*

4. P. monilifera, Ait. COTTON WOOD. A large and very rapidly
growing tree, 75 to 100 or more feet in height, often with a markedly
excurrent trunk. Leaves large and broadly triangular, with crenate-
serrate margins and long, tapering acute tips ; petioles long and
considerably flattened. The numerous pediceled capsules are quite
conspicuous when mature, and the air is filled with the downy
seeds at the time when the capsules open. Common W., espe-
cially along streams and planted as a shade-tree.

H. SALIX, Tourn.

Shrubs or trees, branches usually very slender. Buds with
single scales. Leaves usually long and narrow ; stipules some-
times leaf-like or often small and soon deciduous. Bracts
of the catkins entire ; staminate catkins erect or drooping,
staminate flowers with 2-10, mostly 2, distinct or united
stamens. Pistillate catkins usually erect, flowers with a small
gland on the inner side of the bract, stigmas short, 2-lobed.
Capsule 2-valved.*

1. S. nigra, Marsh. BLACK WILLOW. Leaves elliptical or nar-
rowly lanceolate, acute at each end, serrate, short-petioled, downy
when young and becoming smooth with age, 2-3 in. long ; stipules
persistent or deciduous. Staminate catkins 1-2 in. long ; the pistil-
late 2—4 in. long. Stamens 3-7, distinct, filaments soft, hairy below.
Capsule twice the length of the pedicel, ovate, taper-pointed, pointed
by the prominent style. A small tree with very brittle branches.
Along streams and borders of marshes.*

2. S. babylonica, Tourn. WEEPING WILLOW. Leaves narrowly
lanceolate, taper-pointed, serrate, slightly downy when young and
becoming smooth with age, green above, pale beneath, often 5-7 in.
long, petioles short, glandular. Catkins on short lateral branches.
Stamens 2. Style almost none. Capsule sessile, smooth. Introduced
and cultivated for ornament, becoming a large tree.*

[Some 20 species of willow are found growing wild in the north-
eastern and north central states, but they are very hard, even for
botanists, to identify.]

DICOTYLEDONOUS PLANTS 49

15. MYRICACE.35. BAYBERRY FAMILY.

Shrubs with alternate, simple, resinous-dotted leaves ;
monoecious or dioecious. Flowers in short, bracted catkins,
perianth none. Staminate flowers 2-10, stamens inserted on
the receptacle. Pistillate flowers surrounded by 2-6 scales.
Ovary 1-celled, style short, stigmas 2.

I. MYRICA, L.

Shrubs or small trees with the branches clustered at the
end of the growth of the previous season. Leaves short-
petioled, entire, lobed or toothed, the margin usually revo-
lute, without stipules. Perianth none. Staminate flowers in
oblong or cylindrical catkins, stamens 2-10, with the fila-
ments united below. Pistillate flowers surrounded by a cup
of 2-6 scales, ovary solitary, becoming a 1-celled, roundish
stone-fruit or nut, often covered with waxy grains. Whole
plant usually fragrant.*

1. M. cerifera, L. WAXBERRY, BAYBERRY. A spreading shrub or
small tree ; young branches downy. Leaves lanceolate or oblong-
lanceolate, entire or sometimes serrate near the mostly obtuse apex,
smooth or downy on the veins beneath, tapering into a short petiole.
Flowers mostly dioecious. Staminate catkins numerous, stamens 4.
Pistillate catkins small, bracts slightly 3-lobed, scales of the ovary 4,
fringed with hairs ; stigmas 2. Fruit very abundant, incrusted with
white wax, |— £ in. in diameter, sometimes persistent for 2 or 3 years.
Common on wet soils, especially near the coast.*

2. M. asplenifolia, Endl. SWEET FERN. A shrub 2 ft. or less in
height, with brown twigs. Leaves fern-like, linear-lanceolate, 20-30-
lobed, 3-5 in. long and very fragrant. Often monoecious. Staminate
catkins cylindrical. Pistillate catkins globular. Ovary surrounded
by 8 long, linear, awl-shaped, hairy and glandular scales which en-
circle the ripened fruit. Nut nearly ovoid, smooth, small, but eaten
by children.

16. JUGLANDACE^E. WALNUT FAMILY.

Trees with alternate, odd-pinnate leaves without stipules.
Flowers monoecious, the staminate in long and drooping
catkins, stamens few or many. Calyx 2-6-parted. Fertile

50 FOUNDATIONS OF BOTANY

flowers solitary or in small clusters. Calyx 3-5-lobed, minute
petals sometimes present. Ovary 1-celled or incompletely
2-4-celled. Fruit with a dry husk enclosing a bony nut,*

I. JUGLANS, L.

Staminate catkins cylindrical, solitary, borne on wood of
the previous year, stamens numerous, filaments short, calyx
4-6-parted. Pistillate flowers single or a few together on a
short peduncle at the base of the growth of the season. Calyx
4-parted. Petals 4, minute, adnate to the ovary. Styles 2,
short, plumose. Fruit large, roundish or oval, husk fibrous-
fleshy, becoming dry, indehiscent, nut bony, very rough.*

1. J. nigra, L. BLACK WALNUT. Leaflets 13-21, ovate-lanceo-
late, serrate, taper-pointed, somewhat cordate or oblique at the base,
nearly smooth above, downy beneath, petioles minutely downy.
Fruit usually single, roundish, about 2 in. in diameter. On rich
soil, rare near the coast. One of the most valuable of our native
trees, the wood being very durable and highly prized for cabinet
work.*

2. J. cinerea, L. BUTTERNUT. Leaflets 15-19, ovate-lanceolate,
taper-pointed at the apex, rounded or slightly unsymmetrical at the
base, serrate, downy beneath ; petioles, branchlets, and fruit clothed
with short, sticky hairs. Fruit often somewhat in clusters, oblong,
large. More common northward. Wood less valuable and nut less
oily than the black walnut. The English walnut (J. regia) is
occasionally seen in cultivation. It has 7-11 leaflets and a nearly
smooth nut.*

H. CARYA, Nutt.

Leaflets serrate ; staminate catkins usually in threes on a
common peduncle, or sometimes sessile at the base of the
growth of the season; calyx 2-3-parted, stamens 3-10, fila-
ments short. Pistillate flowers 2-5 in terminal clusters,
calyx 4-parted, petals none, styles 2 or 4, fringed. Fruit
somewhat globular, husk separating more or less completely
into 4 valves. Nut smooth or angled.*

1. C. olivaeformis, Nutt. PECAN. A large tree with rough gray
bark, young twigs and leaves downy, nearly smooth when mature.
Leaflets 11-15, oblong-lanceolate, acuminate, serrate, scythe-shaped.
Staminate catkins nearly sessile, 5-6 in. long. Husk thin nut oval

DICOTYLEDONOUS PLANTS 51

or oblong, thin-shelled. River bottoms. Rarely native east of the
Mississippi River, but widely planted for its fruit.*

2. C. alba, Nutt. SHELLBARK HICKORY. A large tree with bark
scaling off in long plates, young twigs and leaves downy, becoming
smooth with age. Leaflets 5, the lower ones oblong-lanceolate, the
upper one longer and obovate, taper-pointed at the apex, narrowed
to the sessile base. Inner bud-scales becoming large and conspicu-
ous. Staminate catkins in threes. Fruit globose, husk thick, split-
ting into four sections, nut white, compressed, 4-angled, pointed,
thin-shelled. On rich soil. Metre common ]N". Wood strong and
elastic, but not durable when exposed.*

3. C. sulcata, Nutt. BIG SHELLBARK, KING NUT, BULL NUT. A
tree 70-90 ft. high, with shaggy bark. Leaflets 7 or 9, the terminal
one nearly sessile. Fruit large, ovoid or nearly so, 4-grooved toward
the outer end, the husk very thick, nut pointed at each end, 1^-2 in.
long, thick-shelled, with a very sweet kernel. Wood hard and heavy.
Common in rich, damp soil W.

4. C. amara, Nutt. PIGNUT, SWAMP HICKORY. A medium-
sized tree, with rather smooth bark. Leaflets 7-11, lanceolate or
oblong-lanceolate. Fruit not large, husk thin, nut globular, with a
short point, very thin-shelled, kernel extremely bitter. Moist soil,
common in the Middle States.

17. BETULACE^E. BIRCH FAMILY.

Trees or shrubs, with alternate, simple, petioled leaves with
usually deciduous stipules. Flowers monoecious in cylindri-
cal or subglobose catkins, staminate catkins drooping ; flowers
1-3 in the axil of each bract, calyx none, or membranous
and 2-4-parted; stamens 2-10, distinct. Pistillate catkins
drooping, spreading, or erect and spike-like ; flowers with or
without a calyx, ovary solitary, 1-2-celled, ovules 1-2 in each
cell. Fruit a 1-celled nut or key.*

I. CARPINUS, L.

Trees with thin, straight-veined leaves, which are folded
in the bud. Flowers appearing before the leaves ; staminate
flowers in slender drooping catkins, sessile at the end of the
growth of the previous season ; stamens 3-12, subtended by
a bract, filaments forked, anthers hairy. Pistillate catkins

52 FOUNDATIONS OF BOTANY

spike-like, each pair of flowers subtended by a deciduous
bract, and each flower by a persistent bractlet which becomes
large and leaf -like in fruit ; ovary 2-celled, 2-ovuled ; stigmas
2, thread-like. Fruit a small angular nut.*

1. C. caroliniana, Walt. HORNBEAM. A small tree with smooth
and close gray bark ; twigs slender. Leaves ovate-oblong, acute or
taper-pointed, sharply and doubly serrate, the straight veins terminat-
ing in the larger serrations ; downy when young and soon becoming
smooth. Staminate catkins 1-1 £ in. long. Pistillate catkins long-
peduncled, 8-12-flowered ; bractlets becoming nearly 1 in. long, cut-
toothed, the middle tooth much longer than the others. In rich,
moist woods. Often known as " blue beech " and " iron-wood." *

H. OSTRYA, Micheli.

Small trees with gray bark and very hard wood. Leaves
open and concave in the bud and somewhat plaited on the
veins. Staminate flowers on slender, drooping catkins, sessile
at the end of the growth of the previous season ; stamens
3-12, subtended by a bract, filaments forked, anthers hairy.
Pistillate flowers surrounded by a tubular bractlet which
becomes large and bladder-like at maturity. Fruit a small,
pointed, smooth nut; mature catkins hop-like.*

0. virginica, Willd. A small tree with brownish, furrowed bark ;
leaves ovate, acute, doubly serrate, often inequilateral at the base,
short-petioled ; staminate and fertile catkins 2-3 in. long. In rich
woods. Often known as "iron-wood" and "lever-wood."*

m. CORYLUS, Tourn.

Shrubs with prominently veined, cut-toothed leaves which
are folded lengthwise in the bud. Flowers expanding before
the leaves. Staminate flowers in slender, drooping catkins ;
stamens 8, anthers 1-celled. Fertile flowers several in a
cluster or in very short catkins at the ends of the twigs of
the season ; ovary incompletely 2-celled, style short, stigmas
2, bractlets 2, becoming enlarged and enclosing the single
bony nut at maturity.*

1. C. americana, Walt. HAZELNUT. A shrub 2-5 ft. high, young
twigs and petioles covered with brownish, stiff hairs. Leaves not

DICOTYLEDONOUS PLANTS 53

very thin, round-cordate, acute or slightly taper-pointed, irregularly
toothed, nearly smooth above, downy below. Involucre longer than
the nut and partially enclosing it, glandular-hairy. Nut subglobose,
pointed, edible. On rich soil, borders of meadows and fields, and
in oak-openings.

2. C. rostrata, Ait. BEAKED HAZELNUT. A shrub 4-8 ft. high.
Young twigs near ends smooth. Leaves thin, little, if at all, heart-
shaped, doubly serrate or incised, taper-pointed, stipules linear-
lanceolate. Involucre completely covering the nut and prolonged
into a beak beyond it. Common N. [The latter species is not
nearly as widely distributed as the former ; they cannot be readily
distinguished from each other until the fruit is somewhat mature.
The principal points of difference discernible before the fruit is
nearly mature are the hairy twigs of No. 1 and the smooth ones of
No. 2, and the fact that No. 1 has buds rounded at the apex and
more slender and longer staminate catkins, while No. 2 has buds
acute at the apex and thicker and shorter staminate catkins.]

IV. BETULA, Tourn.

Trees with slender, aromatic twigs and thin, usually straight-
veined leaves. Staminate catkins drooping, flowers usually 3
in the axil of each bract, stamens 4, short, anthers 1-celled.
Pistillate catkins erect, flowers 2 or 3 in the axil of each bract ;
ovary sessile, 2-celled, styles 2 ; bracts 3-lobed ; perianth none.
Nut broadly winged.*

1. B. nigra, L. BLACK BIRCH, RIVER BIRCH. A medium-sized
tree with reddish-brown bark. Leaves rhombic-ovate, acute at the
apex, acute or obtuse at the base, sharply and doubly serrate, white-
downy below, becoming smoother with age, petioles short. Stami-
nate catkins 2-3 in. long. Pistillate catkins 1-1 £ in. long, peduncles
short, bracts nearly equally 3-cleft, woolly. River banks, especially
S. and W.*

2. B. lenta, L. CHERRY BIRCH. Leaves ovate or oblong-ovate,
acute, heart-shaped, finely and doubly serrate, silky when young ;
petioles about £ in. long. Staminate catkins clustered, 3-4 in. long.
Pistillate catkins sessile, about 1 in. long, cylindrical bracts spread-
ing, acute, smooth. River banks, especially N. A large tree with
aromatic twigs. The oil contained in the bark and twigs is distilled
and used as a substitute for wintergreeii.*

3. B. populifolia, Ait. GRAY BIRCH. A tall shrub or slender,
straggling tree, 15-30 ft. high, seldom growing erect, often several
trunks springing from the ground almost in contact and slanting
away from each other. Leaves triangular, with a long taper point

FOUNDATIONS OF BOTANY

and truncate base, unevenly twice serrate, with rather long, slender
petioles, which allow the leaves to quiver like those of the aspen.
Bark scaling off in white strips and layers, but not in nearly as
large sheets as that of the rarer canoe birch (B. papyri/era). The
commonest birch of New England.

4. B. alba, L. EUROPEAN WHITE BIRCH, CUT-LEAVED BIRCH.
A tree 50 to 60 ft. high, often with drooping branches. Leaves
triangular-ovate, truncate, rounded or somewhat heart-shaped at
the base, not strongly taper-pointed except in the cut-leaved form.
Commonly cultivated from Europe. Resembles No. 3, but has
whiter bark and (the weeping form) much more slender branches.

V. ALNUS, Tourn.

Shrubs or small trees. Leaves petioled, serrate. Flower-
buds stalked, appearing the previous season ; staminate cat-
kins racemed, drooping, flowers 3-6 in the axil of each bract,
subtended by 1-2 bractlets, perianth 4-parted, stamens 4, fila-

FIG. 8. — Alntis ghttinosa.

A, a flowering twig ; s, staminate catkins ; p, pistillate catkins ; B, a group of
Staminate flowers, enlarged ; C, two pistillate flowers, enlarged.

DICOTYLEDONOUS PLANTS 55

ments short. Pistillate catkins erect ; flowers 2-3 in the axil
of each bract, perianth replaced by 2-4 minute bractlets which
are adherent to the bract ; ovary 2-celled, styles 2. Fruit a
winged or angled nut ; bracts of the pistillate flowers some-
what fleshy, persistent, becoming woody in fruit. *

1. A. serrulata, Willd. SMOOTH ALDER. A shrub or small tree
with smooth bark. Leaves obovate, rounded or obtuse at the apex,
acute at the base, sharply and minutely serrate, smooth above, downy
beneath, petioled, stipules oval, deciduous. Staminate catkins- 2—4
in. long ; fruiting catkins ovoid, short-peduncled. Fruit ovate, wing-
less. Banks of streams and borders of marshes, ranging far S.
Leaves often persistent during the winter.*

2. A. incana, Willd. SPECKLED ALDER. A shrub 8-20 ft. high.
Leaves broadly oval or ovate, rounded at the base, sharply (some-
times doubly) serrate, white and usually downy beneath. Fruit
round. Forming thickets by streams, very common N.

18. FAGACE^E. BEECH FAMILY.

Trees or shrubs. Leaves alternate, simple, pinnately
veined; stipules deciduous. Flowers monoecious, the stami-
nate in heads, or in drooping, spreading, or erect catkins,
calyx minute, petals none, stamens 4-20. Pistillate flowers
solitary or in small clusters, each flower subtended by more
or less united bracts which at maturity form a cup or bur,
calyx minutely toothed, petals none ; ovary 2-7-celled, but
becoming 1-celled. Fruit a 1-seeded nut.*

I. FAGUS, Tourn.

Trees with smooth, close, ash-gray bark, and slender, often
horizontal branches. Staminate flowers in long, slender-
peduncled, roundish clusters, calyx bell-shaped, 4-6-cleft,
stamens 8-12, anthers 2-celled; pistillate flowers solitary or
more oftdh in pairs, peduncled, surrounded by a 4-lobed in-
volucre and numerous linear bracts ; ovaries 3-celled with 2
ovules in each cell, but usually only 1 ovule matures in each
ovary ; styles 3, thread-shaped, fruit a thin-shelled, 3-angled
nut.*

56 FOUNDATIONS OF BOTANY

1. F. ferruginea, Ait. BEECH. Large trees. Leaves oblong-ovate,
taper-pointed at the apex, serrate, straight- veined, very white-silky
when young, nearly smooth with age. Involucre densely covered
with short recurved spines. Nuts thin-shelled, edible. Common on
damp soil everywhere. The wood is very hard, tough, and close-
grained, and is especially valuable for the manufacture of small
tools.*

2. F. sylvatica, L. The European beech is occasionally found
planted as a shade-tree. The variety known as the copper beech
is most usual, and is readily recognized by its dark, crimson-purple
leaves.

H. CASTANEA, Tourn.

Trees or shrubs with rough, gray, rather close bark. Leaves
straight-veined, undivided, prominently toothed. Flowers ap-
pearing later than the leaves. Staminate catkins erect or
spreading, loosely flowered, flowers several in the axil of each
bract, calyx 4-6-parted, stamens 8-16. Pistillate flowers at
the base of the staminate catkin or in small separate clus-
ters, usually 3 in each involucre ; ovary 4-celled, surrounded
by 5-12 abortive stamens. Fruit a 1-celled nut enclosed in
the greatly enlarged and very prickly involucre.*

1. C. sativa, Mill., var. americana, Wats. AMERICAN CHESTNUT.
A large tree, bark somewhat rough, and splitting into longitudinal
plates. Leaves oblong-lanceolate, taper-pointed at the apex, usually
acute at the base, coarsely and sharply serrate with ascending-
teeth, smooth, dark green above, lighter below ; petioles stout,
short. Staminate catkins erect, 6-10 in. long. Nuts usually 3 in
each bur. Rich soil, especially N. Rarely found on soils contain-
ing much lime.*

2. C. pumila, Mill. CHINQUAPIN. A small tree or shrub. Leaves
oblong, acute or obtuse at both ends, serrate with divergent teeth,
dark green and smooth above, white-woolly below. Nuts solitary,
nearly globular. Common southward in rich woods.*

III. QUERCUS, L.

Trees or shrubs with entire, serrate, or lobed leaves, which
are of ten . persistent. Staminate flowers in slender catkins,
each subtended by quickly deciduous bracts, and consisting

DICOTYLEDONOUS PLANTS 57

of 3-12 stamens enclosed by a 4-8-parted perianth, often
containing an abortive ovary. Pistillate flowers solitary or
in small clusters, each consisting of a 3-celled ovary with
2 ovules in each cell, though rarely more than 1 ovule
matures ; styles short, erect, or recurved. Pistillate flowers
surrounded by a scaly involucre which at maturity becomes
a cup enclosing the base of the fruit or sometimes a large
part of it. Fruit an ovoid or subglobose, 1-seeded, thin-
shelled nut (acorn).

A. Fruit biennial ; leaves entire or with bristle-pointed
lobes.*

1. Q. rubra, L. RED OAK. A large tree. Leaves oval or obovate,
green above, pale and slightly downy beneath, sinuses shallow and
rounded, lobes 8-12, taper-pointed ; petioles long. Cup saucer-shaped,
with fine scales ; acorn ovate or oblong, about 1 in. long. Common ;
wood not valuable ; leaves turning red after frost and often remain-
ing on the tree through the winter.*

2. Q. coccinea, var. tinctoria, Gray. BLACK OAK. A large tree
with rough, dark brown outer bark and thick, bright yellow inner
bark; leaves broadly oval, usually cut more than halfway to the
midrib, sinuses rounded ; lobes about 7, sharply toothed at the apex,
smooth above, usually downy on the veins beneath ; cup hemispher-
ical or top-shaped, with coarse scales, short-peduncled, enclosing about
half' the roundish acorn. Common ; wood not valuable, but the
inner bark used for tanning and dyeing.*

3. Q. falcata, Michx. SPANISH OAK. A small or medium-sized
tree with leaves 3-5-lobed at the apex, obtuse or rounded at the
base, grayish-downy beneath, lobes lanceolate and often scythe-
shaped, sparingly cut-toothed. Cup top-shaped, with coarse scales,
enclosing about half the nearly round acorn. Common in diy
woods. Foliage quite variable in outline and lobing ; bark valu-
able for tanning.*

4. Q. nigra, L. BLACK-JACK OAK. A small tree ; leaves obovate,
usually with three rounded lobes at the apex, the lobes bristle-pointed,
rounded, or slightly cordate at the base, rusty-pubescent beneath,
shining above, coriaceous, short-petioled; cup top-shaped, short-
peduncled, with coarse and truncate scales, enclosing about one-
third of the oblong-ovate acorn. An almost worthless tree, its
presence indicating a thin and sterile soil.*

5. Q. Phellos, L. WILLOW OAK. A tree of medium size, leaves
lanceolate or elliptical, scurfy when young and becoming smooth
with age ; very short-petioled ; cup shallow, sessile ; acorn subglobose.
Wet soil ; often planted for shade.*

58 FOUNDATIONS OF BOTANY

B. Fruit annual ; leaves not bristle-tipped, though often
nmcronate.

6. Q. alba, L. WHITE OAK. A large tree with light gray bark.
Leaves obovate-oblong, 3-9-lobed, lobes rounded and mostly entire,
bright green above, paler below, short-petioled. Cup hemispherical,
scales rough, woolly when young, but becoming smooth with age ;
acorn oblong-ovate, about 1 in. long. Common in damp soil ; wood
strong and durable ; one of the most valuable timber trees.*

7. Q. stellata, Wang. POST OAK. A tree of medium size with
rough gray bark. Leaves broadly obovate, deeply lyrate-pinnatified
into 5-7 rounded, divergent lobes, upper lobes much the longer,
smooth above, yellowish-downy beneath, petioles about 1 in. long.
Cup hemispherical, nearly sessile ; acorn ovoid, 2-3 times as long as
the cup. On dry soil ; wood hard and valuable.

8. Q. macrocarpa, Michx. BUR OAK. A medium-sized to very
large tree, with roughish gray bark. Leaves obovate or oblong,
lyrately and deeply sinuate-lobed, smooth above, pale or downy
beneath. Cup very deep and thick, abundantly fringed about the
margin, | in. to 2 in. in diameter. Acorn, half or more [sometimes
entirely] enclosed by the cup. Reaches its full size only on rich
bottom lands S. and W., where it becomes one of the finest timber
oaks. Wood very hard and heavy.

9. Q. lyrata, Walt. SWAMP OAK. A large tree with gray or
reddish bark. Leaves obovate-oblong, deeply pinnatifid, lobes
narrow, often toothed, thin, smooth above, white, densely woolly
beneath. Cup round-ovate, scales cuspidate, enclosing nearly the
whole of the depressed-globose acorn. On wet soil ; wood strong
and very durable.*

10. Q. prinus, L. SWAMP CHESTNUT OAK. A large tree with
brown, ridged bark. Leaves oblong or oblong-lanceolate, rather ob-
tuse, crenately toothed, minutely downy beneath, petioles slender,
about 1 in. long. Cup hemispherical, peduncles longer than the
petioles, scales acute, tubercular, appressed ; acorn oblong, acute,
1 in. or less in length, edible. Common on low ground. Wood
strong and valuable.*

11. Q.- Muhlenbergii, Engelm. YELLOW CHESTNUT OAK. A
tree of medium or large size with gray bark. Leaves oblong or
oblanceolate, usually acute at the apex and obtuse or rounded at the
base, coarsely and evenly toothed ; veins straight, impressed above
and prominent beneath ; petioles slender. Cup hemispherical, sessile
or short-peduncled, with flat scales, ^ in. broad, enclosing about half
the ovoid acorn, which is f-f in. long. Common on dry soil, wood
close-grained, durable, and valuable.

12. Q. virginiana, Mill. LIVE OAK. A large tree with rough

DICOTYLEDONOUS PLANTS

gray or brown bark and a low, spreading top. Leaves leathery,
evergreen, oblong or oblanceolate, often somewhat 3-lobed on young
trees, margin rolled under, dark green and shining above, pale
below ; petioles short, stout. Fruit often in short racemes, cup top-
shaped, scales closely appressed, hoary, peduncles 4—1 in. long ; acorn
from subglobose to oblong, the longer form occurring on the younger
trees. On low ground near the coast ; wood very hard and durable ;
valued for shipbuilding.*

19. ULMACEJE. ELM FAMILY.

Trees or shrubs with watery juice, alternate, simple, petio-
late, serrate, stipulate leaves, which are usually 2-ranked ;
and small, perfect, or somewhat monoecious, apetalous flowers.
Calyx of 3-9 sepals which are distinct or partly united,
stamens as many as the sepals and
opposite them. Ovary 1 — 2 -celled,
styles 2, spreading. Fruit a key,
nut, or stone fruit.*

FIG. 9. — Ulmus campestris.
A, a flowering twig ; B, a flower ; C, longitudinal section of a flower ; Z>, a fruit.

I. ULMUS, L.

Trees with straight-veined, unsymmetrical, doubly serrate
leaves ; stipules early deciduous. Flowers perfect, calyx
bell-shaped, 4-9-cleft. Stamens slender, protruding. Ovary
compressed, styles 2, spreading. Fruit membranaceous, flat,
winged on the edge.*

60 FOUNDATIONS OF BOTANY

1. U. americana, L. WHITE ELM. A large tree with gray bark,
drooping branches, and smooth or slightly downy twigs. Leaves
oval or obovate, abruptly taper-pointed at the apex, obtuse and
oblique at the base, slightly rough above, soft downy or soon smooth
beneath. Flowers in close fascicles, peduncles slender, smooth.
Fruit oval or obovate, with 2 sharp teeth bending toward each
other at the apex, wing reticulate-veined, downy on the margin.
In moist, rich soil. A widely planted ornamental tree; wood
strong but warping badly, and not durable when exposed.*

2. U. alata, Michx. WINGED ELM. A small tree with branches
corky-winged. Leaves small, ovate-lanceolate, acute, sharply serrate,
base nearly equal-sided, rough above, downy beneath, nearly sessile.
Flowers in small clusters. Fruit oblong, downy on the sides, ciliate
on the edges. On rich soil. Occasionally producing a second set of
flowers and fruit from September to November.*

3. U. fulva, Michx. SLIPPERY ELM. A tree of medium size
with rough downy twigs, and rusty, densely woolly bud-scales.
Leaves large, thick, very rough above, downy beneath, ovate or
obovate, taper-pointed at the apex, unsymmetrical, obtuse or some-
what cordate at the base, coarsely and doubly serrate, calyx-lobes
and pedicels downy. Fruit broadly oval, downy over the seed, the
wing smooth. Inner bark very fragrant when dried, and a popular
domestic remedy.*

H. CELTIS, Tourn.

Trees or shrubs with entire or serrate, petioled leaves.
Flowers greenish, axillary, on wood of the same season, the
staminate in small clusters, the fertile single or 2-3 together.*

1. C. occidentalis, L. HACKBERRY. A large or medium-sized
tree having much the appearance of an elm, bark dark and rough.
Leaves ovate, taper-pointed at the apex, abruptly obtuse and inequi-
lateral at the base, sharply serrate, often 3-nerved from the base,
smooth above, usually somewThat downy below. Fruit a small, dark
purple stone fruit. On rich soil.

2. C. mississippiensis, Bosc. SOUTHERN HACKBERRY. A tree
usually smaller than the preceding, bark gray, often very warty.
Leaves broadly lanceolate or ovate, long taper-pointed at the apex,
obtuse or sometimes heart-shaped at the base, entire or with very
few serratures, smooth on both sides, 3-nerved. Fruit a purplish-
black, globose stone fruit.*

DICOTYLEDONOUS PLANTS 61

20. HORACES. MULBERRY FAMILY.

Trees, shrubs, or herbs, usually with milky juice, alternate
leaves, large deciduous stipules and small mono3cious or dioe-
cious flowers crowded in spikes, heads or racemes, or enclosed
in a fleshy receptacle. Staminate flowers with a 3-4-lobed
calyx, stamens 3-4, inserted on the base of the calyx, fila-
ments usually inflexed in the bud, straightening at maturity.
Pistillate flowers 3-5-sepalous ; ovary 1-2-celled, 1-2-ovuled ;
styles 2, receptacle and perianth often fleshy at maturity.*

I. MORUS, Tourn.

Trees or shrubs with milky juice, rounded leaves, and
monoecious flowers in axillary spikes. Staminate flowers
with a 4-parted perianth, and 4 stamens inflexed in the bud.
Pistillate flowers with a 4-parted perianth which becomes
fleshy in the multiple fruit, the pulpy part of which consists
of the thickened calyx, bracts and so on of many flowers ;
ovary sessile, stigmas 2, linear, spreading ; the fleshy perianth
enclosing the ovary at maturity.*

1. M. rubra, L. RED MULBERRY. A small tree. Leaves cor-
date-ovate, often 3-5-lobed on vigorous shoots, taper-pointed at the
apex, serrate, rough above, white, densely woolly beneath. Mature
fruiting spikes oblong, drooping, dark red or purple, edible. On rich
soil. Wood very durable, bearing exposure to the weather.

2. M. alba, L. WHITE MULBERRY. A small tree. Leaves
ovate, heart-shaped, acute at the apex, rounded and often oblique at
the base, serrate or sometimes lobed. Smooth and shining on both
sides. Mature fruit light red or white. Introduced and common
about old dwellings.*

II. MACLURA, Nutt.

A small tree with milky juice. Leaves alternate, petioled,
spines axillary. Flowers dioecious. Staminate flowers in
short axillary racemes ; calyx 4-parted ; stamens 4, inflexed
in the bud. Pistillate flowers in axillary, peduncled, capitate
clusters ; calyx 4-parted, ovaTy sessile, style long ; calyces
becoming thickened and fleshy in fruit and aggregated into a
large, dense, globular head.*

62 FOUNDATIONS OF BOTANY

1. M. aurantiaca, Nutt. OSAGE ORANGE. A small tree with ridged,
yellowish-brown bark. Leaves minutely downy when young, becom-
ing smooth and shining with age, ovate or ovate-oblong, taper-
pointed at the apex, obtuse or subcordate at the base, entire, petioled.
Staminate racemes about 1 in. long. Pistillate flower clusters about
1 in. in diameter. Fruit yellowish, tubercled, 3-4 in. in diameter.
In rich soil. Native in Texas and extensively planted for hedges.
Wood very durable when exposed to the weather, and therefore used
for fence posts. As the wood does not swell or shrink with changes
in its moisture, it is highly valued for wheel hubs, etc.*

III. BROUSSONETIA, L'Her.

Small trees with milky juice. Leaves alternate, petioled ;
flowers dioecious. Staminate in cylindrical spikes, with a
4-cleft calyx, 4 stamens, and a rudimentary ovary. Pistil-
late flowers in capitate clusters. Calyx 3-4-toothed. Ovary
stalked, style 2-cleft, fruit in a globular head.*

1. B. papyrifera, Vent. PAPER MULBERRY. A round-topped tree
with yellowish-brown bark. Leaves cordate, often irregularly 2-3-
lobed, serrate, rough above, downy beneath, long-petioled. Stami-
nate spikelets peduncled, 2-3 in. long. Pistillate heads stout, pedun-
cled, about 1 in. in diameter. Introduced from Asia and very
common S. about old dooryards.*

IV. CANNABIS, Tourn.

Coarse herbs with very tough, fibrous bark. Leaves usu-
ally opposite, palmately compound. Flowers small, dioecious,
greenish, the Staminate ones in compound racemes or panicles,
the pistillate ones in spikes. Calyx of the starninate flowers
of 5 sepals, that of the pistillate flowers of 1 large sepal
which covers the ovary and the akene.

1. C. sativa, L. COMMON HEMP. An erect plant, 4-8 ft. high.
Leaves large, petioled, of 5-7 lanceolate, irregularly serrate or
toothed leaflets. Cultivated from Europe, S. and W., for its fiber,
and sometimes runs wild along roadsides in rich soil.

21. URTICACE^. XETTLE FAMILY.

Herbs with watery juice, stem and leaves often clothed
with stinging hairs. Leaves undivided, stipulate. Flowers

DICOTYLEDONOUS PLANTS 63

small, greenish, imperfect, apetalous in axillary clusters.
Calyx of the staminate flowers 4-5-parted or 4-5-sepalous ;
stamens as many as the sepals and opposite them, filaments
inflexed in the bud and straightening at maturity, anthers
2-celled. Calyx of pistillate flowers 2-4-sepalous ; ovary
sessile, 1-celled, stigma simple or tufted. Fruit an akene
commonly enclosed in the dry, persistent calyx.*

URTICA, Tourn.

Annual or perennial herbs. Leaves with stinging hairs,
opposite, petioled, several-nerved, dentate, or incised, stipulate.
Flowers monoecious or dioecious. Calyx of the staminate
flowers 4-parted ; stamens 4, inserted around a rudimentary
ovary. Pistillate flowers with 4 unequal sepals, the inner
ones dilated in fruit ; akenes smooth, compressed.*

1. U. urens, L. SMALL NETTLE. Annual ; stem stout, 4-angled,
hairy, 12-18 in. tall, with few stinging hairs ; branches slender.
Leaves elliptical or ovate, serrate or incised, 3-5-nerved, acute or
obtuse at the ends, thin, hairy ; petioles often as long as the blades ;
stipules short. Flower clusters axillary, in pairs, loose, mostly
shorter than the petioles. On damp soil in waste places.*

22. LORANTHACEJE. MISTLETOE FAMILY.

Parasitic shrubs or herbs, leaves opposite, leathery, with-
out stipules. Flowers monoecious or dioecious, clustered or
solitary ; perianth of both calyx and corolla, or of a calyx
only, or sometimes wanting ; calyx-tube adnate to the ovary,
sepals 2-8. Stamens as many as the sepals, and opposite
them ; ovary 1-celled, ovule 1. Fruit a berry.*

PHORADENDRON, Nutt.

Evergreen, shrubby plants, parasitic on trees; branches
greenish, jointed, and very brittle. Leaves leathery. Flowers
dioecious, in short jointed spikes. Staminate flowers globular,
calyx 2-4-lobed, stamens sessile at the base of the lobes,

64 FOUNDATIONS OF BOTANY

anthers transversely 2-celled. Pistillate flowers with the
calyx-tube adnate to the ovary, stigma sessile, berry
1-seedecL*

1. P. flavescens, Nutt. AMERICAN MISTLETOE. Very round, bushy ;
branches very brittle at the joints, opposite or whorled, 6 in. to 2 ft.
long. Leaves flat, leathery, or somewhat fleshy, nearly veinless,
obovate, entire, with short petioles. Flowering spikes solitary or
2-3 together in the axils of the leaves. Berry roundish, white,
glutinous. Parasitic on many deciduous trees.*

23. SANTALACE-3L. SANDALWOOD FAMILY.

Herbs, shrubs, or trees with entire leaves. Flowers usually
small. Calyx 4-5-cleft, its tube adnate to the ovary. Corolla
wanting. Stamens as many as the calyx-lobes and opposite
them, inserted on the margin of a fleshy disk. Style 1. Ovary
1-celled, with 2-4 ovules borne at the top of a free central
placenta. Fruit 1-seeded.

COMANDRA, Nutt.

Low, smooth perennials with herbaceous stems, rather
woody below, often parasitic. Leaves alternate and nearly
sessile. Flowers nearly white, in small umbel-like clusters,
perfect. Calyx bell-shaped at first. Stamens borne on a
5-lobed disk which surrounds the pistil, anthers connected
by a tuft of hairs to the calyx-lobes.

1. C. umbellata, Nutt. BASTARD TOAD-FLAX. Plant 8-10 in.
high, with very leafy stems. Roots attached to the roots of trees,
from which they draw nourishment. Leaves oblong or oblanceolate,
pale, nearly 1 in. long. Umbel-like clusters about 3-flowered, longer
than the leaves. Rocky, dry woods.

24. ARISTOLOCHIACEJE. DUTCHMAN'S PIPE FAMILY.

Herbaceous plants, stemless or with twining and leafy
stems. Leaves alternate, without stipules, petioled, mostly
roundish or kidney-shaped. Flowers axillary, solitary or
clustered, perfect, regular or irregular. Calyx tubular, 3 or

DICOTYLEDONOUS PLANTS 65

6 lobed, usually colored. Petals none. Stamens 6-12, inserted
on the ovary. Pistils 1, ovary mostly 6-celled, many-seeded.*

I. ASARUM, Tourn.

Perennial, stemless, aromatic herbs, with slender, branch-
ing rootstocks. Leaves long-petioled, from kidney-shaped to
halberd-shaped. Flowers axillary, peduncled. Calyx regular,
3-lobed, withering-persistent. Stamens 12, the filaments par-
tially united with the style and usually prolonged beyond the
anthers. Ovary 6-celled with parietal placentse, many-seeded.
Mature capsule roundish, often somewhat fleshy.*

1. A. canadense, L. WILD GINGER. Plant soft, hairy. Leaves
2, large, kidney-shaped, on long petioles, with the flower borne on a
short peduncle between them. Flower greenish outside, brownish-
purple inside. Calyx-tube wholly adnate to the ovary, calyx-lobes
taper-pointed, widely spreading, reflexed at the tip. Rich, shady
woods, common N.

2. A. virginicum, L. VIRGINIA ASARUM. Leaves evergreen, 1-3
to each plant, smooth, mottled, round-cordate, entire, 2—3 in. long
and broad; petioles smooth or downy along one side, 3-7 in. long.
Flowers nearly sessile, greenish without, dull purple within, |-| in.
long, tube inflated below, narrow at the throat, lobes spreading.
Rich, shady woods.*

IL ARISTOLOCHIA, Tourn.

Erect or twining perennial herbs or woody vines. Leaves
alternate, heart-shaped at the base, palmately nerved, petioled,
entire. Flowers irregular, solitary, or in small clusters.
Calyx more or less adnate to the ovary, tubular, irregular.
Stamens mostly 6, sessile, adnate to the angled and fleshy
3-6-lobed or angled stigma. Capsule naked, 6-valved, seeds
very numerous.*

1. A. Sipho, L'Her. DUTCHMAN'S PIPE, PIPE VINE. A tall
climber. Leaves dark green, smooth, round-kidney-shaped, some-
times 1 ft. wide. Peduncles 1-flqwered, with a single clasping bract.
Calyx H in. long, bent into the shape of a pipe, its border abruptly
spreading, brownish-purple. Rich woods, often cultivated.

2. A. tomentosa, Sims. DUTCHMAN'S PIPE. Stem woody, climb-
ing high, branches and leaves densely woolly. Leaves heart-shaped,
prominently veined, 3-5 in. long and broad. Flowers axillary,

66 FOUNDATIONS OF BOTANY

mostly solitary, on slender peduncles. Calyx bent in the shape of
a pipe, yellowish-green with a dark purple throat, limb unequally
3-lobed, rugose, reflexed. Anthers in pairs below the 3 spreading
lobes of the stigma. Capsule oblong. Stems sometimes 30 ft. long.
Rich woods S.*

25. POLYGONACE^). BUCKWHEAT FAMILY.

Herbs with alternate, entire leaves and usually with sheath-
ing stipules above the swollen joints of the stem. Flowers
apetalous, generally perfect, with a 3-6-cleft calyx, generally
colored and persistent. Fruit a compressed or 3-angled akene,
enclosed in the calyx. Seeds with endosperm, which does not
generally enclose the embryo. Stamens 4-12, on the base of
the calyx.

I. RUMEX, L.

Coarse herbs, many of them troublesome weeds. Flowers
small, usually green or greenish, generally in whorls borne in
panicled racemes. Calyx of 6 nearly distinct sepals, the 3
inner larger and more petal-like than the 3 outer, and one
or more of them usually with a little knob or tubercle on its
back. Stamens 6. Styles 3. Stigmas short, fringed. Fruit
a 3-angled akene, closely covered by the 3 inner calyx-lobes,
enlarged and known as valves.

1. R. Acetosella, L. SHEEP SORREL. Erect annual or perennial
herbs with creeping rootstocks. Stem simple or branched, smooth.
Leaves petioled, narrowly halberd-shaped, usually widest above the
middle, the apex acute or obtuse, upper stem-leaves often nearly
linear and not lobed. Flowers dioecious, small, in terminal, naked,
panicled, interrupted racemes. Calyx greenish ; the pistillate pani-
cles becoming reddish. Fruit less than T^ in. long, granular, longer
than the calyx. A common introduced weed, in dry fields and on
sour soils. Foliage very acid.* •

2. R. verticillatus, L. SWAMP DOCK. Perennial, stem stout,
smooth, erect or ascending, 3-5 ' ft. tall. Lower leaves oblong,
obtuse at the apex and usually heart-shaped at the base, long-
petioled, often 12-18 in. long, upper leaves narrower and often
acute at both ends. Flowers perfect or somewhat monoecious, in
dense whorls, pedicels slender, i-| in. long, tapering downward,

DICOTYLEDONOUS PLANTS 67

reflexed at maturity. Calyx green, the valves broadly triangular,
abruptly pointed, reticulated, a distinct long and narrow tubercle on
the back of each. Swamps and wet ground.*

3. R. crispus, L. YELLOW" DOCK. Stout, smooth, 3-4 ft. high.
Leaves lanceolate, margins very wavy, acute, the lower more or less
heart-shaped. Root long, tapering gradually downward, yellow,
very tough. Flowers in whorls crowded in long, straight, slender
racemes. Valves roundish heart-shaped, mostly tubercled. A very
hardy weed, introduced from Europe.

II. POLYGONUM, L.

Annual or perennial, terrestrial or aquatic herbs, with
enlarged joints and simple, alternate, entire leaves ; the
sheathing stipules often cut or fringed. Flowers perfect,
usually white or rose-colored, each flower or cluster subtended
by a membranaceous bract, similar to the stipules of the
leaves. Calyx mostly 5-parted, the divisions petal-like, erect
and persistent. Stamens 3-9. Styles 2-3-parted. Fruit
lens-shaped or 3-angled.*

1. P. aviculare, L. KNOT-GRASS. Annual or perennial. Stem
prostrate or ascending, diffuse, smooth, 6-24 in. long. Leaves small,
lanceolate or linear-oblong, obtuse, nearly

or quite sessile. Stipules thin and dry, 2-3-
cleft or cut. Flower-clusters axillary, 1-5-
flowered, flowers inconspicuous, nearly ses-
sile. Calyx greenish-white, 5-parted, the
lobes with white or colored borders. Stamens
5-8. Style 3-parted ; akene 3-angled, not
shining. A common weed in dooryards and A B

where the ground is trampled.* FIG. 10.— Buckwheat.

2. P. DumetOrum, L. FALSE BUCK- A, flower, longitudinal sec-
WHEAT. Perennial ; stems slender, twining, tion '•> B> fruit (both some-
branched, 2-10 ft. long. Leaves ovate, ^ -larged>-
taper-pointed, heart-shaped to halberd-shaped at the base, long-
petioled. Stipules cylindrical, truncate. Flowers in axillary, more
or less compound and leafy racemes. Calyx greenish-white, the
outer lobes winged and forming a margin on the pedicel. Stamens
8. Stigmas 3 ; akene 3-angled, black, smooth, and shining. Margins
of fields and thickets.*

68 FOUNDATIONS OF BOTANY

26. CHENOPODIACE^. GOOSEFOOT FAMILY.

Herbs or shrubs. Leaves simple, alternate, without sti-
pules. Flowers small, regular, either perfect or more or
less monoecious or dioecious. Calyx free from the ovary.
Corolla wanting. Stamens usually 5, opposite the sepals.
Styles or stigmas generally 2. Fruit with 1 seed, usually
enclosed in a small, bladdery sac, sometimes an akene.

I. SPINACIA, Tourn.

Herbs. Flowers dioecious, in close axillary clusters. Stami-
nate flowers 3-5-sepaled, with 4 or 5 projecting stamens.
Pistillate flowers with a tubular 2-toothed or 4-toothed calyx.

1. S. oleracea, Mill. SPINACH. A soft annual or biennial herb.
Leaves triangular, ovate, or halberd-shaped, petioled. Cultivated
from Asia as a pot-herb.

n. CHENOPODIUM, Tourn.

Annual or perennial herbs. Stems erect or spreading.
Leaves alternate, usually white-mealy. Flowers small, green-

FiG. \\.-Chenopodium.
A, flower ; B, fruit.

ish, in panicled spikes. Calyx 3-5-parted, the lobes often
slightly fleshy and keeled. Stamens 5 ; filaments thread-
shaped. Styles 2-3, distinct or united at the base. Seed
lens-shaped.*

DICOTYLEDONOUS PLANTS 69

1. C. hybridum, L. MAPLE-LEAVED GOOSEFOOT. A tall annual
herb 2-4 ft. high. Leaves 2-6 in. long, thin, bright green, long,
taper-pointed, with several angled lobes on each side, terminating in
pointed teeth. Flower-clusters rather large, consisting of loosely
paiiicled racemes. A rather common weed.

2. C. Botrys, L. JERUSALEM OAK. A low spreading plant cov-
ered with sticky down. Leaves with slender petioles, oblong, sin-
uately lobed or the lobes pinnate. Flowers in loose, diverging,
leafless racemes. The whole plant is sweet-scented. Introduced
from Europe and. naturalized in gardens and along roadsides.

27. PHYTOLACCACEJE. POKEWEED FAMILY.

Plants with alternate entire leaves. Flowers perfect, 5-
parted, with the characters of the Goosefoot Family, but the
ovary generally consisting of several carpels, which unite to
form a berry.

PHYTOLACCA, Tourn.

Perennial herbs. Stems tall, branching. Leaves large,
entire. Flowers small, in terminal racemes, pedicels bracted.
Calyx of 4-5 nearly equal, persistent sepals. Stamens 5-15,
inserted at the base of the calyx. Styles 5-12, recurved at
the apex. Fruit a depressed-globose, juicy berry.*

1. P. decandra, L. POKEWEED. Stems erect, smooth, branched
above, usually dark purple, 4-7 ft. tall ; root large, fleshy, poisonous.
Leaves ovate-lanceolate, smooth, acute, long-petioled. Racemes pedun-
cled, many-flowered, opposite the leaves, flowers white, becoming
purplish. Stamens 10, shorter than the sepals. Styles 10, car-
pels 10; fruit a dark purple berry. A weed on waste ground.
The young branches are often eaten like asparagus, and the root,
known as " garget root," is used in medicine.*

28. AIZOACE^:. ICE-PLANT FAMILY.

Mostly fleshy plants, mainly natives of Africa. Flowers
often large and showy. Stamens often doubled and some of
them petal-like. Ovary 2-many-celled.

[Our only very common genus belongs to a subfamily
which has little resemblance to the fleshy " ice-plants," found
in some gardens, which best represent the family as a whole.]

70 FOUNDATIONS OF BOTANY

MOLLUGO, L.

Low branching annuals. Sepals 5, greenish outside, white
inside. Corolla wanting. Stamens 5, alternate with the
sepals, or 3, alternate with the cells of the ovary. Capsule
3-celled, many-seeded.

1. M. verticillata, L. CARPET-WEED. Stems branching and
forming radiating patches. Leaves clustered in apparent whorls at
the joints of the stem, spatulate. Flowers in little sessile umbels at
the joints. Stamens commonly 3. A troublesome weed in sandy
soil and common on sandy beaches and river banks.

29. PORTULACACE^E. PURSLANE FAMILY.

Generally herbs. Leaves opposite or alternate, entire ;
stipules dry and membranaceous. Sepals 2. Petals 4 or
more, distinct or united below. Stamens 4 or more, free or
adnate to the petals. Ovary usually free, 1-celled; style
simple or 3-cleft ; ovules 2-many. Capsule opening trans-
versely with a lid, or 2-3-valved.

I. CLAYTONIA, Gronov.

Perennial ; stem simple, smooth, erect, 4-10 in. high.
Leaves 2, opposite, smooth, succulent. Flowers in a terminal
raceme. Sepals 2, ovate, persistent. Petals 5, sometimes
coherent at the base. Stamens 5, inserted on the base of
the petals. Style 3-cleft, ovary 1-celled, 3-6-seeded.

1. C. virginica, L. SPRING BEAUTY. Stem simple, erect from a
deep, tuberous root. The 2 stem-leaves narrowly elliptical, 3-6 in.
long, smooth, fleshy; basal leaves occasionally produced. Flowers
on short pedicels. Petals white or pink, with darker veins, ^-f in.

\ long, notched. Capsule shorter than the persistent sepals. Common
\ in rich woods.*

2. C. caroliniana, Michx. NORTHERN SPRING BEAUTY. Flowers
fewer, smaller, and whiter than No. 1, fragrant. Leaves 1-2 in.
long, ovate-lanceolate or spatulate, pretty distinctly petioled. Moist
woods, especially N.

DICOTYLEDONOUS PLANTS 71

II. PORTULACA, Tourn.

Annual ; stems low, diffuse, and spreading, fleshy. Leaves
entire, mostly alternate. Flowers terminal. Sepals 2f united
at the base and coherent with the ovary. Petals usually 5, in-
serted on the calyx, quickly withering. Stamens 8-20, inserted
on the calyx. Style 3-8-parted. Capsule globose, opening
by the upper portion coming off like a lid, 1-celled, many-
seeded.*

1. P. oleracea, L. PURSLANE. Stems prostrate, diffuse, fleshy.
Leaves alternate, flat, obovate, or wedge-shaped. Flowers solitary,
sessile, opening in bright sunshine in the morning, and usually
withering before noon. Sepals broad, acute. Petals yellow. Sta-
mens 10-12. Capsule very-many-seeded, seeds small, wrinkled. A
common garden weed.*

2. P. grandiflora, Hook. GARDEN PORTULACA. Stems fleshy,
erect, or ascending, densely hairy or nearly smooth, 3-6 in. long.
Leaves alternate, cylindrical, fleshy, £-1 in. long. Flowers 1-2 in.
wide, white, yellow, or red, showy, opening only in sunlight. Com-
mon in cultivation and often growing spontaneously.*

30. CARYOPHYLLACEJE. PINK FAMILY.

Herbs sometimes woody below, with thickened nodes.
Leaves opposite, entire ; stipules small and dry or none.
Sepals 4-5. Petals 4-5 (rarely 0), usually hypogynous. Sta-
mens usually 8-10, hypogynous or perigynous. Styles 2-5
(rarely 1). Ovules 2-many. Fruit a capsule.

Sepals distinct or nearly so. Petals (if any} without claws. Capsule

several-many-seeded.

Styles usually 3. Capsule ovoid. Stellaria; I.

Styles 5 or 4. Capsule cylindrical. Cerastium, II.

Sepals united into an urn-shaped tube. Petals none. Fruit 1-seeded.

Scleranthus, III.

72 FOUNDATIONS OF BOTANY

Sepals more or less united. Petals with claws. Capsule several-
many-seeded.

(a) Calyx without bracts, its lobes long and leaf-like.

Agrostemma, IV.
(&) Calyx without bracts, lobes not leaf-like. Styles 3 or 4.

Silene, V.

Lychnis, VI.
(d} Calyx with little bracts at the base. Styles 2.

Dianthus, VII.

I. STELLARIA, L. Chickweed.

Slender, usually smooth herbs. Flowers small, white, soli-
tary, or in forking cymes. Sepals 5 (rarely 4). Petals 5
(rarely 4), 2-cleft or divided. Stamens 10 (rarely 8, 5, or 3),
maturing in 2 sets. Styles 3 (rarely 4 or 5), opposite the same
number of petals ; ovary 1-celled, many-ovuled. Capsule
short, splitting into as many valves as there are styles.

1. S. media, Cyrill. COMMON CHICKWEED. Stem prostrate,
6-18 in. long, with a line or two of hairs along it. Leaves ovate,
taper-pointed, the lower petioled, the upper sessile. Petals shorter
than the sepals, sometimes wanting. An annual weed, introduced
from Europe, common in damp, shady places N.

2. S. longifolia, Muhl. LONG-LEAVED STITCHWORT. Stem
slender, usually erect, 8-18 in. high, often sharply 4-angled. Leaves
linear or nearly so, spreading. Flower-clusters peduncled, many-
flowered, the pedicels spreading. Petals 2-parted, at length longer
than the calyx. Perennial in meadows and grassy thickets, espe-
cially N.

H. CERASTIUM, L.

- Annual or perennial. Stems diffuse, usually downy ; leaves
opposite. Flowers white, peduncled, in terminal, regularly
forking cymes. Sepals 4-5. Petals 4-5, notched or 2-cleft.
Stamens 10. Styles 5 or less. Capsule cylindrical, 1-celled,
many-seeded.*

1. C. vulgatum, L. MOUSE-EAR CHICKWEED. Annual or some-
times perennial. Stems diffuse, tufted, clammy-downy, 6-12 in.

DICOTYLEDONOUS PLANTS 73

high. Lower leaves spatulate, the upper oblong, acute, or obtuse ;
bracts thin and dry. Flowers in loose cymes, pedicels becoming
much longer than the calyx. Sepals lanceolate, acute, about as long
as the 2-cleft petals. Slender capsule becoming twice as long as the
calyx aiid-curved upward. A common garden weed.*

HI. SCLERANTHUS, L.

Low tufted herbs. Leaves opposite, clasping, awl-shaped,
sharp-pointed. Flowers very small and greenish. Calyx-
tube funnel-shaped or urn-shaped, hardening into an envelope
for the fruit ; calyx-lobes 4-5, short, erect. Petals none.
Stamens 1, 2, 5, or 10, inserted on the throat of the calyx.
Styles 2, thread-like. Fruit 1-seeded, never opening.

1. S. anmms, L. KNAWEL. A much-branched annual weed,
2-8 in. high. Stem and leaves pale green ; the leaves \ to \ in.
long, rather prickly pointed. Flowers solitary in the lower axils
and somewhat clustered above. Calyx-teeth with narrow whitish
margins. Introduced from Europe, common in sandy roads and
waste ground E.

IV. AGROSTEMMA.

Annual ; stem pubescent, branching above. Leaves linear-
lanceolate or linear, pubescent, sessile. Flowers showy, on
long and naked peduncles in terminal corymbs. Calyx tubu-
lar, the tube oblong, 10-ribbed, lobes elongated, leaf -like,
deciduous. Petals 5, shorter than the calyx lobes, entire.
Stamens 10. Styles 5, capsules 1-celled.*

1. A. Githago, L. CORN COCKLE. Stem erect, rather slender, 1-3
ft. tall, gray, with long, appressed hairs. Leaves linear-lanceolate,
acuminate, erect, 2-4 in. long. Petals obovate, notched, purple.
Capsule 5-toothed, many-seeded ; seeds black. An introduced weed,
common in grain fields.*

V. SILENE, L.

Annual or perennial herbs. Stems erect or decumbent and
diffuse. Leaves often connate or whorled. Flowers clustered
or solitary, usually pink or white. Calyx tubular, more or
less inflated, 5-toothed, 10-nerved, bractless. Petals 5, long-
clawed, and with the ten stamens inserted at the base of the
ovary. Styles 3, ovary 1-celled or 3-celled at the base, open-
ing by 6 teeth, many-seeded. Seeds usually roughened.*

74 FOUNDATIONS OF BOTANY

1. S. Cucubalus, Wibel. SNAPPERS, RATTLEBOX. A perennial
branched herb about 1 ft. high. Leaves opposite, smooth, ovate, or
ovate-lanceolate. Calyx thin and bladdery, beautifully veined.
Petals white, 2-cleft. Capsule nearly globular. In fields and along
roadsides, especially eastward. Introduced from Europe.

2. S. pennsylvanica, Michx. WILD PINK. A perennial with low-
clustered stems (4-8 in.). Root-leaves wedge-shaped or spatulate,
those of the stem lanceolate. Flowers medium-sized, clustered.
Petals wedge-shaped, notched, pink, with a crown at the throat of
the corolla. Gravelly soil E.

3. S. virginica, L. FIRE PINK. A slender perennial with erect
stem, 1-2 ft. high. Root-leaves spatulate, the upper leaves oblong-
lanceolate. Flowers few, peduncled, large and showy, bright crim-
son. Corolla crowned, petals deeply 2-cleft. Woods.

4. S. Armeria, L. CATCHFLY, NONE-SO-PRETTY. A smooth, erect
annual or biennial, 6-15 in. high. Several nodes of the stem are
usually covered for part of their length with a sticky substance.
Leaves very smooth, with a bloom beneath, lanceolate or oblong-
lanceolate, clasping. Flowers showy, dark pink, nearly £ in. in
diameter, in flat-topped clusters. Calyx club-shaped. Petals some-
what notched. Cultivated from Europe and introduced.

5. S. antirrhina, L. SLEEPY CATCHFLY. Stem smooth, slender,
8—30 in. high, sticky in spots. Leaves lanceolate or linear. Flowers
rather few and small, panicled. Calyx ovoid. Petals inversely
heart-shaped, pink, opening only for a short time in sunshine. Dry
waste ground.

6. S. noctiflora, L. NIGHT-FLOWERING CATCHFLY. A tall, coarse
annual or biennial weed, covered with sticky hairs. Lower leaves
spatulate, the upper ones lanceolate and pointed. Flowers large,
white, opening at night or in cloudy weather. Calyx-teeth very long
and awl-shaped. Petals 2-parted. In fields and gardens, introduced
from Europe.

VI. LYCHNIS, L.

Plants with nearly the same characteristics as Silene, but
usually with 5 styles.

1. L. chalcedonica, L. SCARLET LYCHNIS, LONDON PRIDE. A
tall, hairy perennial, (about 2 ft.). Leaves lance-ovate, somewhat
clasping. Flower-cluster flat-topped and very dense. Flowers
bright scarlet, not very large. Petals 2-lobed. Common in old
gardens ; from Russia.

2. L. coronaria, Lam. MULLEIN PINK. A forking perennial
plant, 2 ft. high, covered with white, cottony down. Root-leaves
very wavy, spatulate ; stem-leaves ovate-lanceolate, wavy, clasping.

DICOTYLEDONOUS PLANTS 75

Peduncles long, 1-flowered. Flowers about 1^ in. broad, deep crim-
son. Calyx-tube very strongly 5-ribbed, with 5 smaller ones between ;
calyx-teeth short and slender. Petals somewhat notched. Culti-
vated in old gardens ; from Italy.

VII. DIANTHUS, L.

Tufted, mostly perennial herbs, often shrubby at the base.
Leaves narrow and grass-like. Flowers solitary or variously
clustered. Calyx tubular, 5-toothed, with overlapping bracts
at the base. Petals 5, with long claws. Stamens 10, matur-
ing 5 at a time. Styles 2 ; ovary 1-celled. Capsule cylindrical,
4-valved at the top.

1. D. Armeria, L. DEPTFOKD PINK. Rather erect, annual, with
stiff stems 1-2 ft. high. Leaves very dark green, linear, 1-2 in. long,
the lower obtuse, the upper acute. Flowers loosely clustered, small,
dark pink. Calyx-tube £-f in. long, nearly cylindrical. Petals
narrow, speckled with very small whitish dots. In sandy fields
eastward, introduced from Europe; sometimes cultivated.

2. D. barbatus, L. SWEET WILLIAM. Perennial, often in large
clumps. Stems erect, branching above, smooth, 1-2 ft. tall. Leaves
lanceolate, 2—3 in. long, acute. Flowers crimson-pink, white or
variegated, in terminal clusters, bracts linear, as long as the calyx.
Common about old gardens ; from Europe.*

3. D. plumarius, L. COMMON PINK, GRASS PINK. Leaves grass-
like, with a whitish bloom. Petals white, pink, or variegated, with
the limb fringed. Flowers solitary, fragrant. Hardy perennials,
cultivated from Europe.

4. D. Caryophyllus, L. CARNATION, CLOVE PINK. Much like
the preceding species, but with larger fragrant flowers ; the broad
petals merely crenate. Hothouse perennials (some hardy varieties),
cultivated from Europe.

31. NYMPILSEACEJE. WATER-LILY FAMILY.

Perennial aquatic herbs. Leaves usually floating, often
shield-shaped. Flowers borne on naked scapes. Floral en-
velopes and stamens all hypogynous or else adnate to a fleshy
disk that encloses the carpels. Sepals 3-6. Petals 3-5 or
often very numerous. Stamens many. Carpels 3 or more,
free, in a single circle or united with the disk. Fruit a berry
or a group of separate carpels.

76 FOUNDATIONS OF BOTANY

I. NELUMBO, Toura.

Eootstock large and stout. Leaves round, shield-shaped,
often raised above the water. Flowers large, raised above
water at first, but often submerged after blooming. Sepals
and petals hypogynous, numerous, the inner sepals and outer
petals not distinguishable from each other. Stamens many,
hypogynous. Pistils several, 1-ovuled, borne in pits in the
flattish upper surface of a top-shaped receptacle, which, en-
larges greatly in fruit.

1. N. lutea, Pers. AMERICAN LOTUS. WATER CHINQUAPIN.

Rootstock often 3-4 in. in diameter, horizontal. Leaves 1^-2^ ft.
broad, prominently ribbed, with much bloom above, often downy
beneath. Petioles and peduncles stout. Flowers pale yellow, 5-9
in. broad. Sepals and petals falling quickly. Fruit top-shaped,
3-4 in. in diameter ; the seeds ^ in. in diameter. In ponds and
slow-running streams W., introduced from the Southwest.*

II. NYMPH^A, Toura.

Rootstock horizontal, creeping extensively. Leaves float-
ing, entire, shield-shaped or heart-shaped. Flowers showy.
Sepals 4, green without, white within. Petals many, white,
becoming smaller towards the center. Stamens many, the
outer with broad and the inner with linear filaments. Ovary
many-celled, stigmas shield-shaped and radiating. Fruit berry-
like, many-seeded.*

1. N. odorata, Ait. WHITE WATER-LILY. Rootstock large,
branched but little. Leaves floating, entire, the notch narrow, and
basal lobes acute, green and smooth above, purple and downy
beneath. Petioles and peduncles slender. Flowers white, very
fragrant, opening in the morning, 3-5 in. broad. Fruit globose,
seeds enclosed in a membranaceous sac. In ponds and still water.*

m. NUPHAR, Smith.

Rootstock horizontal, thick, cylindrical. Leaves heart-
shaped, floating or erect. Flowers yellow. Sepals 4-6,
green on the outside, obovate, concave. Petals many, hypogy-
nous, the inner ones becoming small and stamen-like. Sta-
mens many, hypogynous. Ovary cylindrical, many-celled,
stigma disk-shaped. Fruit ovoid.*

DICOTYLEDONOUS PLANTS 77

1. N. advena. YELLOW POND LILY, Cow LILY, SPATTERDOCK.
Leaves oval or orbicular, rather thick, often downy beneath. Flowers
bright yellow, 2-3 in. in diameter, depressed-globular. Sepals 6.
Petals thick and fleshy, truncate. Stamens in several rows, anthers
nearly as long as the filaments. In slow streams and still water.*

32. RANUNCULACEJE. BUTTERCUP FAMILY.

Herbs, rarely shrubs, usually with biting or bitter juice.
Leaves radical or alternate (in Clematis opposite ; stem-leaves
or involucre whorled in anemone) ; stipules none or adnate to
the petiole. Floral organs all distinct and unconnected.
Sepals 5 or more (rarely 2-4), falling early, often petal-like.
Petals none, or 5 or more (rarely 3). Stamens many. Carpels
many, 1-celled ; stigmas simple ; ovules 1 or more. Fruit
composed of 1-seeded akenes or many-seeded follicles. Seeds
small

Flowers irregular.

With a spur. Delphinium, VII.

With a hood. Aconitum, VIII.

Flowers regular.

1. Petals present (in c not very unlike the stamens).

(a) Petals very large and showy. Paeon ia, I.

(&) Petals small, tubular at the tip. Coptis, IV.

(c) Petals narrow, spatulate, on slender claws. Actsea, V.
(e?) Petals prolonged backward into spurs. Aquilegia, VI.
(e) Petals flat, with a little scale at the base, inside.

Ranunculus, XIII.

2. Petals none, or very small and stamen-like.

(a) Sepals yellow. Calfha, II.

(b) Sepals greenish or white, falling as the flower opens.

Thalictrum, XIV.

(d) Sepals 4. Plants climbing. Clematis, XII.

78 FOUNDATIONS OF BOTANY

(e) Sepals 5, white. Flowers axillary and terminal. Pods
2-several-seeded. Isopyrum, II I.

(/) Sepals white or colored. Plants not climbing. Akenes
more or less tailed with the styles in fruit.

Anemone, IX.

(g) Sepals 5-10, white. Flowers in an umbel. Roots
tuberous. Anemonella, XI.

I. P^EONIA, L.

Perennial ; from thick, fleshy roots ; stems shrubby or her-
baceous. Leaves much divided. Flowers terminal, large and
showy. Sepals 5, leaf-like and persistent. Petals 5 or more.
Pistils 3-5 ; ovaries surrounded by a disk.*

1. P. officinalis, L. GARDEN P^ONY. Herbaceous; flowering-
stems 1-2 ft. high. Leaves ample ; leaflets lance-ovate, cut or
incised, smooth. Flowers double, white or red. Follicles 2, erect,
many-seeded. Common in gardens.*

H. CALTHA, L.

Smooth perennials with large, roundish leaves. Sepals
petal-like, 5-9. Petals none. Pistils 5-10, each consisting
of a 1-celled ovary with a nearly sessile stigma. Fruit a
many-seeded follicle.

1. C. palustris. MARSH MARIGOLD, COWSLIPS, MEADOW BUTTER-
CUP (both the latter unsuitable names, but in common use). Stem
hollow, smooth, ascending ; leaves smooth, roundish and heart-
shaped, or kidney-shaped, with crenate, dentate, or nearly entire
margins; the broad oval sepals bright yellow. Swamps or wet
ground.

m. ISOPYRUM, L.

Small, smooth herbs. Leaves 2-3 times compound, in
threes j the leaflets 2-3-lobed. Flowers peduncled, white.
Sepals 5, petal-like, soon falling. Petals wanting (in our
species). Stamens 10-40. Pistils 3-6 or more.

1. I. biternatum, Torr. and Gr. A delicate, erect plant, with alter-
nate branches, looking much like Anemonella, with clustered steins
from perennial tuberous roots. Damp woods.

DICOTYLEDONOUS PLANTS 79

IV. COPTIS, Salisb.

Low, smooth perennials with 3-divided root-leaves. Flowers
small, white, on scapes. Sepals 5-7, petal-like, soon fall-
ing. Petals 5-7, small, club-shaped, tubular at the apex.
Stamens 15-25. Pistils 3-7, stalked. Pods thin and dry,
4-8-seeded.

1. C. trifolia, Salisb. GOLD THREAD. A pretty, delicate plant,
with slender, 1-flowered scapes, from long, bright-yellow, thread-like
rootstocks, which are bitter and somewhat medicinal. Leaves later
than the flowers, each of 3 wedge-shaped leaflets, which finally
become shining and evergreen. Damp, cold woods and bogs.

v. ACT;EA, L.

Perennial ; stem simple. Leaves 2-3, compound in threes.
Leaflets ovate, sharply cut or toothed. Flowers white, in a
short and thick terminal raceme. Sepals 4-5, soon decidu-
ous. Petals 4-10, small. Pistil single ; stigma 2-lobed.
Fruit a many-seeded berry.*

1. A. alba, Bigel. BANEBERRY. Stem erect, smooth or nearly so,
18-24 in. high. Leaves large and spreading ; leaflets thin. Racemes
very broad. Petals slender, truncate. Pedicels red, thickened in
fruiting; berries white. In rich woods, more common S.*

2. A. spicata, var. rubra, Ait. RED BANEBERRY. Stem about
2 ft. high. Raceme ovoid or hemispherical. Petals acute. Pedicels
slender. Berries usually red, sometimes white, ovoid. Common N".

VI. AQUILEGIA, Tourn.

Perennials with leaves twice or thrice palmately compound,
the divisions in threes.

Sepals 5, petal-like, all similar. Petals 5, all similar, each
consisting of an expanded portion, prolonged backward into
a hollow spur, the whole much longer than the calyx. Pistils
5, forming many-seeded pods.

1. A. canadensis, L. WILD COLUMBINE. Flowers scarlet with-
out, yellow within, nodding ; spurs rather long.

2. A. vulgaris, L. GARDEN COLUMBINE. Flowers often double
and white, blue, or purple. Spurs shorter and more hooked. Cul-
tivated from Europe, and sometimes become wild.

80 FOUNDATIONS OF BOTANY

VII. DELPHINIUM, Tourn.

Annual or perennial herbs ; stem erect, simple, or branched.
Leaves alternate, petioled, palmately divided. Flowers in ter-
minal racemes or panicles, showy. Sepals 5, colored, irregu-
lar, the upper one prolonged into a spur. Petals 4, unequal,
the two upper ones with long spurs which are enclosed in the
spur of the upper sepal, the other two short-stalked. Pistils
1-5 ; ovaries many-seeded.*

. 1. D. tricorne, Michx. DWARF LARKSPUR. Perennial. Stem
simple, from a tuberous root, usually low (^ to 1 ft. high), but some-
times 2 ft. high. Leaves deeply 5-parted, the divisions irregularly
3-5-cleft. Racemes few-flowered, loose. Flowers blue, sometimes
white. Pods diverging. Southward.

2. D. azureum, Michx. BLUE LARKSPUR. Perennial. Stem
usually simple, slender, downy, 1-2 ft. high. Leaves 2-3 in. wide,
3-5-parted, the divisions cleft into 3-5 narrow, toothed, or entire
lobes. Flowers in a strict, many-flowered, terminal raceme, showy,
blue or whitish. Spur ascending, curved ; lower petals bearded, 2-
cleft. Pods erect. On rich or rocky soil in open places. Northward.*

VHI. ACONITUM, L.

Erect, perennial herbs. Leaves alternate, palmately lobed
or cut. Flowers irregular, in panicles or racemes. Sepals 5,
the back one large, arched, and hooded, the front one the
narrowest. Petals 2-5, small, the 2 back ones clawed and
covered by the hood of the sepals ; 3 lateral ones small
or wanting. Follicles 3-5. Seeds many, wrinkled.

1. A. Napellus, L. MONKSHOOD. An erect, poisonous plant,
1-2 ft. high. Raceme simple and densely flowered. Flowers dark
blue. Cultivated from Europe.

IX. ANEMONE, Tourn.

Perennial herbs, usually with radical leaves, and 2 or 3
opposite or whorled stem-leaves, constituting an involucre
some distance below the flower or flower-cluster. Sepals few
or numerous, colored and petal-like. Petals usually wanting.
Akenes pointed, or with long, feathery tails.

1. A. patens, var. nuttalliana, Gray. PASQUE FLOWER. Low

plants, 1 in. to 1 ft. high, clothed with long, silky hairs. Leaves

DICOTYLEDONOUS PLANTS 81

divided in threes. Flower single, large, showy, pale-purplish, borne
on a peduncle developed before the leaves. Carpels many, with long,
hairy styles, which in fruit form tails 2 in. long. Prairies and
bluffs, N. W.

2. A. caroliniana, Walt. CAROLINA ANEMONE. Stem simple,
from a roundish tuber, slightly downy, 6-12 in. high, bearing a
single flower about 1 in. broad. Root-leaves 2-3, long-petioled, com-
pound in threes, the divisions cut or lobed ; stem-leaves sessile,
compound in threes, the divisions wedge-shaped. Sepals 12-20,
white; head of fruit becoming oblong; akenes woolly. In open
woods W.*

3. A. cylindrica. LONG-FRUITED ANEMONE. Plants about 2
ft. high, branching, with an involucre of long-petioled, divided and
cleft leaves, from within which spring several long, naked peduncles.
Flowers greenish-white. Sepals obtuse. Head of fruit cylindrical,
composed of very many densely woolly akenes. Dry woods and
prairies.

4. A. virginiana, L. Plant hairy, 2-3 ft. high. Peduncles 6-12
in. long, sometimes forking, the first ones naked, the later ones with
a little 2-leaved involucre at the middle. Leaves of the involucre 3,
each 3-parted, the divisions ovate-lanceolate, pointed. Sepals acute.
Head of fruit ovoid. Woods and meadows.

5. A. quinquefolia, L. WIND-FLOWER, WOOD ANEMONE. , Stem
simple, from a thread-like rootstock ; involucre of 3 leaves, each
petioled, and of 3 leaflets, which are cut, toothed, or parted. Pedun-
cle 1-flowered. Sepals 4-7, white, often tinged with purple outside.
Carpels 15 or 20. This species is very nearly related to, but now
regarded as distinct from, the European A. nemorosa.

X. HEP ATICA, Dill.

Involucre of 3 small, simple leaves, so close to the flower as
to look like a calyx. Leaves all radical, 3-lobed, heart-shaped,
thick, and evergreen, purplish-red beneath. Flowers single,
on rather slender hairy scapes.

1. H. triloba, Chaix. ROUND-LOBED HEPATICA. Lobes of the
leaves obtuse or rounded ; those of the involucre obtuse ; sepals
6-12, varying from blue to white.

2. H. acutiloba, DC. SHARP-LOBED HEPATICA. Closely similar
to the former, except for the acute lobes of the leaves and tips of
the involucre.

[Both species have many local names, such as Liverleaf , Liverwort,
Noble Liverwort, Spring Beauty.]

82 FOUNDATIONS OF BOTANY

XI. ANEMONELLA, Spach.

Small, perennial herbs. Leaves compound, smooth, those
from the root long-petioled, those of the stem sessile. Flowers
in a terminal umbel, slender-pediceled. Sepals petal-like.
Petals none. Pistils 4-15 ; stigmas sessile, truncate.*

1. A. thalictroides, Spach. RUE ANEMONE. Stem slender, 6-10 in.
high, from a cluster of tuberous roots. Radical leaves long-petioled,
twice compound in threes, leaflets oval, heart-shaped, 3-5-lobed.
Stem-leaves 2-3 compound in threes whorled, the long-stalked leaf-
lets veiny, forming an involucre of 6-9 apparently simple leaves.
Flowers 3-6 in an umbel, £-£ in. wide ; sepals 6-10, white. In rich
woods.*

XH. CLEMATIS.

Perennial herbs or slightly woody vines, usually climbing
by the leaf-stalks. Leaves opposite, simple, or compound.
Sepals 4, petal-like. Petals very small or wanting. Pistils
numerous,- tipped by the persistent styles which often become
long and plumose in fruit.*

1. C. crispa, L. MARSH CLEMATIS. Stem climbing, a little
woody below, slightly downy above, 3-5 ft. high. Leaves pinnately
compound; leaflets 5-7, varying from lanceolate to ovate, thin,
entire, or 3-5-lobed. Flowers showy, perfect, solitary, on long, axil-
lary peduncles. Sepals lanceolate, taper-pointed, thick, wavy on the
margins, twice the length of the stamens, light bluish-purple, 1-1^
in. in length. Tails of the ripened akenes 1 in. long, silky. Rich
woods and river banks S.*

2. C. viorna, L. LEATHER FLOWER. Stem climbing, nearly
smooth, 6-10 ft. long. Leaves usually pinnately compound, the
lowest pair often compound in threes and the upper pair simple.
Leaflets usually 5-7, oblong-ovate or oval, acute, firm, entire, or
lobed. Calyx bell-shaped, nodding ; sepals ovate, taper-pointed with
a short, recurved point, thick and leathery, reddish-purple, 1 in. long.
Tails of the akenes plumose, l£ in. long, brownish. On river banks
and rich soil.*

XIII. RANUNCULUS, Tourn.

Annual or perennial herbs. Leaves alternate, usually
deeply lobed or parted. Flowers axillary or in corymbs,
white or yellow. Sepals 3-5. Petals 3-5, flat, with a small

DICOTYLEDONOUS PLANTS 83

pit or scale inside at the narrowed base. Stamens usually
numerous. Pistils few or several in a head. Akenes flattened,
pointed.*

1. R. pusillus, Poir. Low SPEARWORT. Perennial. Stems sev-
eral, erect or ascending, branched, smooth, 6-15 in. high. Leaves
entire or slightly toothed, the lower round or cordate, long-petioled,
the upper lanceolate or elliptical, nearly or quite sessile. Flowers
very small, about £ in. wide, yellow. Petals 1-5, as long as the
sepals. Stamens 3-10. Akenes smooth, with a very short point.
On muddy banks.*

2. R. abortivus, L. SMALL-FLOWERED CROWFOOT. Perennial.
Stems smooth, branching, 12-18 in. high. Root-leaves round-cor-
date, crenate, petioled. Stem-leaves 3-5-parted, with wedge-shaped
or linear divisions, sessile. Flowers very small, pale yellow. Sepals
reflexed, longer than the petals. Akenes in a globose head, smooth,
without a beak. Common on wet ground and waste places.*

3. R. recurvatus, Poir. HOOKED CROWFOOT. Perennial. Stem
erect, hairy, 1-2 ft. high. Leaves all nearly alike, petioled, 3-5-lobed
with the lobes wedge-shaped, cut or toothed at the apex. Flowers
small, pale yellow. Petals minute, shorter than the reflexed sepals.
Akenes in a globular head, smooth, with a slender, recurved beak.
On low ground.*

4. R. pennsylvanicus, L. BRISTLY CROWFOOT. Perennial. Stems
rough-hairy, erect, 2-3 ft. high. Leaves compound in threes, on
long and very hairy petioles; leaflets long-stalked, 3-parted, the
divisions sharply lobed or toothed. Flowers small. Petals yellow,
shorter than the sepals. Akenes flat, smooth, in oblong heads, beak
broad and straight. On low ground.*

5. R. bulbosus, L. BULBOUS BUTTERCUP, EARLY BUTTERCUP.
Stem upright, from a solid bulb about as large as a filbert, about
1 ft. high, hairy. Root-leaves 3-divided, the divisions lobed and
cleft. Peduncles furrowed. Flowers large and showy (^ to 1 in. in
diameter). Sepals strongly reflexed. Petals roundish, wedge-shaped
at the base. Akenes with a very short beak. Introduced from
Europe. Common in grass fields in New England.

6. R. acris, L. TALL BUTTERCUP. Erect, hairy, 2-3 ft. high.
Leaves 3-7-parted, the divisions of the lower ones wedge-shaped,
deeply cut and lobed. Peduncles not furrowed. Sepals spreading,
downy. Petals obovate, a little smaller and paler yellow than in
No. 5. A common weed, introduced from Europe, in grass fields
and elsewhere, especially eastward.

84 FOUNDATIONS OF BOTANY

XIV. THALICTRUM, L.

Erect perennial herbs. Leaves compound, with stipules.
Flowers in panicles or racemes, often somewhat monoecious
or dioecious, wind-fertilized. Sepals 4-5, petal-like. Petals
none. Stamens many. Carpels few or many ; ovule 1. Fruit
a small head of akenes. [The following species are both
usually dioecious.]

1. T, dioicum, L. EARLY MEADOW RUE. Plant 1-2 ft. high,
smooth and pale or with a bloom. Leaves all petioled, most of them
thrice compound in threes ; leaflets thin and delicate, roundish, 3-7-
lobed. Flowers in slender panicles, purplish or greenish ; staminate
ones with slender, thread-like filaments, from which hang the con-
spicuous yellowish anthers. Rocky woods and hillsides.

2. T. polygamum, Muhl. TALL MEADOW RUE. Stems from
fibrous roots, tall and coarse, nearly or quite smooth, 4-8 ft. tall.
Leaves twice compound, those of the stem sessile, the others long-
petioled ; leaflets oval or oblong, often cordate, smooth or downy
beneath, quite variable in size on the same plant. Flowers small,
in large panicles. Sepals 4 or 5, white. Filaments club-shaped.
Akenes short-stalked. Thickets and meadows E.

33. BERBERIDACE^. BARBERRY FAMILY.

Herbs or shrubs. 'Leaves alternate, simple or compound,
usually without stipules. Sepals petal-like. Petals hypogy-
nous, distinct, their number some multiple of 2, 3, or 4, never
of 5. Stamens one opposite each petal, anthers opening by
2 uplifted lids. Pistil 1, 1-celled, ovules 2 or more. Fruit
a berry or capsule.

I. BERBERIS, L.

Spiny shrubs with yellow wood. Leaves spinous-toothed,
jointed on the very short petiole, often reduced to 3-7-cleft
spines. Flowers in racemes, solitary, or in pairs. Sepals
8—9, the outer minute. Petals 6, each with 2 nectar glands
at the base. Stamens 6. Ovules few. Berry 1-2-seeded ;
seeds bony-coated.

1. B. vulgaris, L. COMMON BARBERRY. A shrub 4-6 ft. high.
Leaves obovate, spinous-serrate ; those on the old shoots mere

DICOTYLEDONOUS PLANTS 85

spines. Flowers pale yellow, in drooping racemes. Stamens irrita-
ble, closing quickly toward the center of the flower when touched.
Berry £ in. long, nearly ellipsoidal in shape, scarlet or orange-scarlet,
very acid, eatable when cooked. Cultivated from Europe and intro-
duced in eastern New England and locally in the upper Mississippi
valley.

2. B. Thunbergii, DC. A low shrub. Leaves entire, turning
red and remaining so for a considerable time in autumn. Flowers
solitary or in pairs. Berries bright red, remaining on the branches
all winter. Cultivated from Japan.

II. CAULOPHYLLUM, Michx.

A perennial smooth herb, 1-2-J- ft. high. Leaf large, single,
sessile, thrice compound in threes, borne high up on the stem ;
there is also a large, very compound radical leaf. Flowers
racemed or panicled, yellowish-green. Sepals 6, with 3 bract-
lets. Petals 6, gland-like, somewhat curved inward at the
tip, much smaller than the sepals. Pistil 2-ovuled, the ovary
soon bursting open and leaving the 2 blue seeds to ripen naked.

1. C. thalictroides, Michx. BLUE COHOSH, PAPPOOSE ROOT.

Whole plant purplish and covered with a bloom when young.
Flowers appearing before the leaf is fully developed. Rich woods.

HI. PODOPHYLLUM, L.

Perennial. Stem simple, smooth, erect, 12-15 in. tall, bear-
ing 2 leaves with a large white flower between them. Sepals
6, falling off as the flower opens. Petals 6-9, obovate. Sta-
mens twice as many as the petals. Pistil 1, stigma large, flat,
sessile. Fruit berry-like, 1-celled, many-seeded.*

1. P. peltatum, L. MAY-APPLE. Rootstock rather large. Leaves
orbicular, shield-shaped, 5-9-lobed and toothed, smooth, 9-12 in.
wide. Flowers 1—2 in. wide, on a peduncle 1—2 in. long. Stamens
prominent, anthers opening longitudinally. Fruit 1^-2 in. long,
oval, fragrant, edible ; each seed surrounded by a pulpy covering.
In rich woods. The roots and leaves are used in medicine.*

34. MAGNOLIACEJE. MAGNOLIA FAMILY.

Trees or shrubs. Leaves alternate, not toothed or serrate.
Flowers solitary, large, and showy. Floral envelopes and

86 FOUNDATIONS OF BOTANY

stamens hypogynous. Calyx and corolla colored alike, the
parts of the perianth forming 3 or more circles of 3 parts
each. Stamens many. Carpels many, usually cohering over
the long receptacle and forming a sort of cone-shaped fruit,
which may be either fleshy or dry.

I. MAGNOLIA.

Aromatic trees or shrubs ; leaves alternate, often in clus-
ters at the ends of the branches, entire, usually thick and
leathery ; stipules large, quickly deciduous ; flowers termi-
nal, showy, perfect ; sepals 3, caducous ; petals 6-12, in 2-4
rows, concave; stamens numerous ; ovaries numerous, 1-celled,
2-seeded, the mature follicles opening at the beak, and the
fleshy seeds remaining for some time suspended by slender
threads.*

1. M. grandiflora, L. LARGE-FLOWERED MAGNOLIA. A large
tree with spreading branches and a rounded top ; bark nearly
smooth. Leaves very thick, evergreen, smooth and shining above,
rusty-downy beneath, entire, oval or oblong, 6-9 in. long. Flowers
white, very fragrant, 6-9 in. in diameter. Petals 9 or more, obovate,
concave. Fruit a rusty-downy cone 3-4 in. long, seeds bright scarlet.
Common on light soils in Arkansas and the Gulf States.*

2. M. Fraseri, Walt. LONG-LEAVED UMBRELLA TREE. A small
tree with a slender trunk and widely spreading branches. Leaves
clustered at the ends of the branches, deciduous, oblong or obovate,
contracted, cordate and eared at the base, smooth on both sides,
8-12 in. long ; petioles slender. Flowers white and fragrant, 6 in.
broad. Petals longer than the sepals, spatulate or oblong, obtuse at
the apex, narrowed at the base. Cone 3-4 in. long, pink at maturity.
In rich woods S.*

3. M. macrophylla, Michx. LARGE-LEAVED UMBRELLA TREE.
A small tree with gray bark. Leaves clustered at the ends of the
branches, oblong or obovate, obtuse at the apex, cordate at the base,
green and glabrous above, white and downy beneath, H-3 ft. long-
petioles stout. Flowers white with a purple center, fragrant, 8-12
in. wide ; petals oblong, obtuse, two or three times as long as the
sepals. Cone ovate, 4-6 in. long, bright red at maturity. Shady
woods on light soil S.*

4. M. virginiana, L. SWEET BAY. A small tree with light gray
bark. Leaves scattered on the branches, evergreen, thick and
leathery, oval or oblong, smooth, and green above, white and with

DICOTYLEDONOUS PLANTS 87

a bloom, downy beneath, 4-6 in. long. Flowers white, fragrant, 2-3
in. in diameter; petals 9, concave. Cone 1^-2 in. long, pink. Com-
mon in swamps and along streams, New York and southward (a
few in eastern Massachusetts). The leaves often used in flavoring
soups, etc.

II. LIRIODENDRON, L.

A large tree with rough, dark-colored bark. Leaves scat-
tered on the branches, deciduous, 3-lobed, truncate, stipuled,
petioled. Flowers perfect. Sepals 3, reflexed. Petals 6,
erect. Stamens numerous. Ovaries numerous, 2-ovuled,
cohering over each other on the elongated receptacle, never
opening, deciduous.1*

1. L. tulipifera, L. TULIP TREE. The largest tree in the family.
Leaves roundish in outline, mostly 3-lobed, the terminal lobe trun-
cate or broadly notched, usually heart-shaped at the base, smooth,
green above, lighter beneath. Petioles slender. Flowers terminal,
bell-shaped, greenish-yellow marked with orange. Petals obovate,
obtuse, about as long as the sepals. Mature cones ovate, acute,
2-3 in. long. Common on low ground, Pennsylvania and S. Often
called " white wood " or, incorrectly, " white poplar." Wood valua-
ble for making boxes and light furniture.*

35. CALYCANTHACE^E. CALYCANTHUS FAMILY.

Shrubs. Leaves opposite, entire, without stipules. Flowers
solitary, often sweet-scented. Sepals and petals numerous,
the outer sepals bract-like. Stamens many, short, the inner
ones usually sterile. Ovaries several, inserted on the inside
of an irregular, hollow, pear-shaped receptacle something like
a large rose-hip, forming 1-seeded akenes in fruit.

CALYCANTHUS, L.

Shrubs, 4-8 ft. tall; branches opposite. Leaves oval,
downy beneath, short-petioled 5 both leaves and bark aro-
matic. Sepals and petals many, in several rows, somewhat
fleshy, indistinguishable. Pistils several, inserted on the
inner side of the persistent calyx-tube. Mature fruit pear-
shaped, dry, enclosing the akenes.*

88 FOUNDATIONS OF BOTANY

1. C. floridus, L. SWEET-SCENTED SHRUB, STRAWBERRY BUSH,
SPICE BUSH, SHRUB. A widespreading bush, 4—8 ft. high ; twigs
downy. Leaves oval or oblong, acute or taper-pointed, rough
above, downy beneath, 2-3 in. long. Flowers 1 in. wide, brownish-
purple, very fragrant ; sepals united below to form a cup, on the
inside of which the other parts of the flower are inserted, cup leafy-
bracted on the outside. Banks of streams and rich hillsides S.,
often cultivated.*

36. ANONACEJE. PAWPAW FAMILY.

Trees or shrubs. Leaves alternate, entire ; pinuately veined.
Flowers perfect, hypogynous, axillary, solitary. Calyx of 3
sepals, corolla of 6 thickish petals in 2 rows. Stamens many,
filaments very short. Pistils several or many, becoming
fleshy or pulpy in fruit.

ASIMINA, Adans.

Shrubs or small trees. Leaves deciduous. Flowers nod-
ding. Sepals 3, ovate. Petals 6, the 3 outer ones larger
and spreading. Stamens very numerous, crowded on the
globular receptacle. Ovaries 3-15, sessile, 1-celled, several-
ovuled. Fruit a large, fleshy, oblong berry, seeds large,
horizontal.*

1. A. triloba, Dunal. PAWPAW. A small tree, 10-20 ft. high ;
bark nearly smooth, lead-colored. Leaves oblong-obovate, acute at
the apex, obtuse at the base, rusty-downy when young and becoming
smoother with age, 6-10 in. long. Flowers on branches of the
previous season, appearing before or with the leaves ; the short
peduncles and the sepals brown-downy. Petals purple, obovate, 3-4
times longer than the sepals. Fruit 3—5 in. long, edible when ripe.
Common on banks of streams, especially S. and S. W. The bark
is very tough and is often used in the place of rope.*

37. LAURACEJE. LAUREL FAMILY.

Aromatic plants, nearly always trees or shrubs. Leaves
alternate, simple, usually entire, and marked with translucent
dots. Calyx regular, hypogynous, of 4 or 6 colored sepals.

DICOTYLEDONOUS PLANTS 89

Stamens in 3 or 4 circles of 3 each, the anthers opening by
valves. Style single. Fruit a 1-seeded berry or stone-fruit.

I. SASSAFRAS, Nees.

A tree with rough, yellowish bark and a spreading top.
Leaves deciduous, entire or 2-3-lobed. Flowers dioecious, in-
volucrate, at the end of the twigs of the previous season.
Calyx 6-parted, persistent in the pistillate flowers. Stamens
9, in 3 rows. Pistillate flowers with 4-6 abortive stamens
and a single ovary. Fruit a stone-fruit.*

1. S. officinale, Nees. SASSAFRAS. A tree, usually small and
slender, but sometimes with a trunk 3 ft. in diameter and 125 ft.
high. Leaves oval, entire, mitten-shaped or 3-lobed, downy when
young but becoming smooth with age, dark green above, paler
below, petiolate. Racemes several in a cluster, peduncled ; flowers
yellow. Stamens about as long as the sepals. Fruit dark blue,
ovoid, on thickened, red pedicels. All parts of the tree aromatic ;
trees producing pistillate flowers rare. Common. The wood is
valuable for cabinet-making, and an aromatic oil is extracted from
the bark.*

H. LINDERA, Thunb.

Shrubs ; leaves deciduous, entire. Flowers in lateral,
sessile clusters, appearing before the leaves, dioecious or
somewhat monoecious. Involucre of 4 scales. Stamens 9 in
the staminate flowers, filaments slender. Pistillate flowers
with 12-15 abortive stamens and a single globose ovary with
a short style.*

1. L. Benzoin, Blume. SPICE BUSH. A shrub, 5-15 ft. high,
with smooth bark and slender twigs. Leaves oblong-obovate, acute
at the base, pale and downy beneath, becoming smooth when old ;
petioles short. Flowers about as long as the pedicels, yellow, very
fragrant. Ovary about as long as the style. Fruit an obovoid, red
stone-fruit about ^ in. long, on a slender pedicel. Banks of streams
and damp woods. Twigs and leaves quite aromatic.*

38. PAPAVERACEJE. POPPY FAMILY.

Annual or perennial herbs, often with milky juice. Leaves
sometimes all radical, stem-leaves usually alternate without

90 FOUNDATIONS OF BOTANY

stipules. Flowers perfect, regular or irregular. Sepals
usually 2, shed as the flower opens. Petals 4-12, falling
early. Stamens numerous or 6 (in 2 sets), 4, or 2. Carpels
2-16. Fruit a capsule.

I. ESCHSHOLTZIA, Cham.

Annual or perennial herbs. Leaves pale or bluish-green,
usually cut into very narrow divisions. Sepals united into a
pointed cap, which falls off in one piece as the flower opens.
Petals 4, orange or yellow. Stamens many, with long anthers.
Stigmas 2-6, spreading. Pods long and slender, grooved. Re-
ceptacle often surrounded by a rim on which the calyx rests.

1. E. californica, Cham. Annual or perennial, with rather suc-
culent leafy stems. Flowers large and showy, yellow or orange-
yellow. Receptacle top-shaped, with a broad rim. Cultivated from
California.

H. SANGUINARIA, Dill.

Perennial. Rootstock thick, horizontal, joints and scars
of previous growths persistent several years ; juice orange-
colored. Leaves on long petioles, kidney-shaped. Scape
1-flowered. Sepals 2, falling off as the flower opens. Petals
8-12. Ovary 1, stigmas 2 ; capsule oblong, seeds crested.*

1. S. canadensis, L. BLOODROOT. Leaves and scape with a
bloom ; leaves palmately 5-9-lobed, lobes rounded or toothed ; scapes
naked, nearly as long as the petioles. Flowers white, 1 in. or more
wide. Petals oblong or obovate, quickly deciduous. Capsule
1 -celled, 2-valved, the valves separating from the persistent placentae
at maturity. In rich, open woods.*

m. CHELIDONIUM, L.

Erect, branched, perennial herbs with yellow juice. Leaves
much divided. Flowers yellow. Sepals 2, falling as the
flower opens. Petals 4. Ovary 1-celled ; style dilated at the
top, with 2 adnate stigmas. Capsule linear.

1. C. majus, L. CELANDINE. Stem 1-2 ft. high, brittle, slightly
hairy, leafy. Leaves once or twice pinnate. Flowers small. A rather
common weed in yards and along fences. Introduced from Europe.

DICOTYLEDONOUS PLANTS 91

IV. PAPAVER.

Annual or perennial herbs with milky juice. Stem erect,
smooth, or rough-hairy, branching above. Leaves more or
less lobed or dissected. Flower-buds nodding, flowers showy.
Sepals commonly 2, falling off as the flower opens. Petals
4-6. Stamens many. Stigma disk-like, ovules many, borne
on many inwardly projecting placentae.*

1. P. somniferum, L. OPIUM POPPY. Annual; stem erect,
branched above, smooth and with a bloom, 2-3 ft. high. Leaves
oblong, irregularly lobed or cut, sessile, clasping. Flowers nearly
white, with a purple center, large and showy, on long peduncles.
Capsule globose, seeds minutely pitted. About old gardens and
waste places. Cultivated in southern Asia, where the juice of the
capsules is dried to make opium.*

2. P. dubium, L. CORN POPPY. Annual ; stem slender, branch-
ing, 1-2 ft. tall. Leaves pinnatifid, the lower petioled, the upper
sessile. Flowers large and showy, usually red; capsule long-
obovoid, smooth. In cultivated ground. Both the species named
are often cultivated in gardens and produce double flowers.*

3. P. orientate, L. ORIENTAL POPPY. A large, rough-hairy
perennial. Leaves large, deep green, almost pinnate. Flower very
large, deep red. Cultivated from the eastern Mediterranean region.

4. P. nudicaule, L. ICELAND POPPY. A delicate but rough-
hairy perennial plant. Leaves all radical, pale, pinnately cut.
Flowers yellow-orange or white, borne singly on rather slender,
hairy scapes. Cultivated from Europe.

V. DICENTRA, Borkh.

Smooth, delicate herbs with watery juice. Leaves com-
pound in threes and finely cut. Flowers racemed, nodding.
Sepals 2, small and scale-like. Petals 4, slightly united to
form a heart-shaped or 2-spurred corolla (Fig. 12), the inner
pair spoon-shaped, enclosing the stamens and pistil. Stamens
6 ; the filaments somewhat united into 2 sets, and the anthers
in 2 sets close to the stigma. Stigma 2-crested. Pod 10-20-
seeded.

1. D. Cucullaria, DC. DUTCHMAN'S BREECHES, BREECHES
FLOWER. A low, stemless perennial, with a delicate scape and a
cluster of root-leaves with linear divisions from a sort of bulb made

FOUNDATIONS OF BOTANY

of small, scaly grains. Flowers in a 4-10-flowered simple raceme, not
fragrant. Spurs of the corolla longer than the pedicels; corolla
mostly white with a yellowish tip. Rich woods, common.

2. D. canadensis, DC. SQUIRREL CORN, WILD HYACINTH. A
low, stemless perennial, with scape and leaves much as in No. 1, and
with small yellow tubers looking like grains of corn scattered along
the underground shoots. Corolla only heart-shaped at the base,
whitish or flesh-colored, very fragrant. Rich woods.

3. D. spectabilis, DC. BLEEDING HEART, EAR DROPS. Stems
branching, recurved. Leaves large, twice compound in threes, the
divisions rather broad, like those of the common peony. Racemes
long, drooping, many-flowered. Flowers large, heart-shaped, bright
pink. Cultivated from China.

VI. ADLUMIA, Raf.

A delicate climbing biennial. Leaves thrice-pinnate, cut-
lobed. Sepals 2, very small. Petals 4, all united into a corolla
which is slightly heart-shaped or 2-knobbed at the base, remain-
ing as a spongy covering over the small, few-seeded pod.

A B

FIG. 12. — Flower of Dicentra.

A, view of flower partly dissected ; p, the larger outer petals ; p', the spoon-
shaped inner petals ; £, floral diagram.

1. A. cirrhosa, Raf. MOUNTAIN FRINGE, ALLEGHANY VINE.

Climbing several feet high by the leaf-stalks. Flowers pinkish-
white. Rocky hillsides, often cultivated.

DICOTYLEDONOUS PLANTS 93

VII. CORYDALIS, Vent.

Leafy-stemmed Biennial herbs (the American species).
Leaves much divided, alternate or nearly opposite. Racemes
terminal or opposite the leaves. Sepals 2, small. Petals 4 ;
corolla with a single spur at the base, on the upper side.
Capsule many-seeded.

1. C. glauca, Pursh. PALE CORYDALIS. Plant erect, covered
with a bloom. Flowers pink-purple with yellow tips. Spur of the
corolla very short and rounded. Rocky woods.

2. C. aurea, Willd. GOLDEN CORYDALIS. A low, spreading plant,
finally ascending. Corolla bright yellow, 1-2 in. long; the spur
shorter than the pedicel, somewhat bent. Shaded, rocky banks.

39. CRUCIFERJE. MUSTARD FAMILY.

Herbs with pungent, watery juice and alternate leaves with-
out stipules. Sepals 4, often falling off early. Petals usually
4, arranged in the form of a cross. Stamens 6, the 2 outer
ones shorter than the 4 inner ones. Fruit generally a pod,
divided into two cells by a thin partition which stretches
across from one to the other of the two placentae. The
flowers throughout the family are so much alike that the gen-
era and species cannot usually be determined without examin-
ing the tolerably mature fruit.

Pods short and flattened, contrary to the partition, splitting open when ripe.
Pod roundish. Lepidium, I.

Pod triangular, inversely heart-shaped. Capsella, IX.

Pods globular or cylindrical, splitting open when ripe.

(a) Pods globular. Flowers white. Petals much longer

than the calyx. Cochlearia, II.

(5) Pods cylindrical; seeds ellipsoid. Flowers very small,

yellow. Sisymbrium, III.

94 FOUNDATIONS OF BOTANY

(e?) Pods cylindrical. Flowers white. Or pods ovoid or
ellipsoid. Flower yellowish. Aquatic plants, or
growing in wet soil. Nasturtium, VI.

Pods elongated, often jointed, tapering toward the tip, never splitting
open. Raphanus, V.

Pods flattened parallel to the partition, splitting open when ripe.

(a) Wild species leafy-stemmed ; growing in or near water.

Pods linear. Cardamiiie, VII.

(&) Wild species ; stems naked below, bearing only 2 or 3

leaves. Pods lanceolate. Dentaria, VIII.

or rocks. Pods linear; seeds usually winged or
margined. Arabia, X.

(d) Cultivated species. Pods round or roundish.

Lobularia, XI.

(e) Cultivated species, covered with a grayish down of

star-shaped hairs. Pods cylindrical.

Matthiola, XII.

I. LEPIDIUM, Tourn.

Annual ; stem erect, or sometimes diffuse. Leaves entire,
toothed, or pinnately divided. Flowers in a terminal raceme,
small, white. Petals short, sometimes wanting. Stamens 2,
4, or 6. Pod rounded or obcordate, flattened contrary to the
partition.*

1. L. virginicum, L. PEPPERGRASS, BIRDS' PEPPER, TONGUE-
GRASS. Stem erect, smooth, much branched, 1-2 ft. high. Lower
leaves obovate in outline, pinnately cut with dentate lobes ; upper
leaves lanceolate, dentate, slightly downy. Flowers on slender
pedicels, petals present, sometimes reduced in the later flowers.
Stamens 2. Pod round. A weed growing in waste places.*

DICOTYLEDONOUS PLANTS 95

II. COCHLEARIA, Tourn.

Perennial herbs. Leaves entire or pinnate. Flowers
small, white. Sepals short. Petals with short claws. Pods
globular or ellipsoid.

1. C. Armoracia, L. HORSE-RADISH. A coarse herb with large
leaves from stout, long, cylindrical rootstocks filled with a very
sharp, biting juice. Root-leaves long-petioled, linear-oblong, obtuse,
regularly scalloped ; stem-leaves sessile. Racemes in panicles.
Pods obovoid, on long, slender pedicels. Seeds seldom or never
ripening. Probably from Europe ; cultivated and often introduced
in damp ground.

HI. SISYMBRIUM, Tourn.

Annual or biennial herbs. Radical leaves spreading ; stem-
leaves alternate, often eared at the base. Flowers in loose
racemes, usually yellow, often bracted. Pods generally nar-
rowly linear, cylindrical or 4-6-angled. Seeds many, ellip-
soid, not margined.

1. S. canescens, Nutt. TANSY MUSTARD. Stem 1-2 ft. high.
Leaves twice pinnately cut, usually covered with grayish down.
Flowers very small, yellowish. Pods oblong, club-shaped, 4-angled,
borne on pedicels projecting almost horizontally from the stem, in
long racemes. Common westward.

2. S. officinale, Scop. HEDGE MUSTARD. Stems branching, stiff.
Leaves runcinate-toothed or lobed. Flowers very small, pale yel-
low. Pods somewhat 6-sided, awl-shaped, closely pressed against
the stem. An unsightly weed in waste ground, introduced from
Europe.

IV. BRASSICA, Tourn.

Branching herbs. Leaves often pinnately cut. Flowers
in racemes, rather large, yellow. Sepals spreading. Pods
nearly cylindrical, sometimes tipped with a beak which does
not open. Seeds globular.

1. B. arvensis, Boiss. CHARLOCK. Stem 1-2 ft. high; it and the
leaves rough-hairy. Upper leaves rhombic-toothed or no. Flowers
£-f in. across, somewhat corymbed, bright yellow. Pods knotty,
spreading, at least % of each consisting of a 2-edged, 1-seeded beak.
A showy, troublesome weed in grain fields, introduced from Europe.

96 FOUNDATIONS OF BOTANY

2. B. juncea, Coss. Similar to the preceding, but nearly or quite
smooth. Pedicels slender. Beak of the cylindric pod slender,
conical, not containing a seed. Recently introduced from Asia and
becoming very abundant eastward.

3. B. alba, Boiss. WHITE MUSTARD. Stem 2-5 ft. high, with
reflexed hairs. Upper leaves pinnately cut. Pods borne on spread-
ing pedicels, bristly, with a sword-shaped, 1-seeded beak occupying
more than half their length. Seeds pale. Cultivated from Europe
and introduced to some extent.

4. B. nigra, Koch. BLACK MUSTARD. Stem 3-6 ft. high, some-
what hairy. Lower leaves lyrate with the terminal lobe much the
longest, stem-leaves linear-lanceolate, entire or toothed, smooth.
Pods awl-shaped, 4-angled, smooth, lying against the stem. Seeds
brownish, more biting than in No. 2. Cultivated from Europe and
introduced.

V. RAPHANUS, Tourn.

Annual or biennial herbs. Boot-leaves lyrate. Flowers in
long racemes, white or yellow, purple-veined. Sepals erect.
Pods rather long, slender-beaked, not splitting open but some-
times breaking across into 1-seeded joints.

1. R. Raphanistrum, L. WILD RADISH, JOINTED CHARLOCK.
A stout, hairy annual 1—2 ft. high. Leaves cut into remote seg-
ments, which are coarsely toothed or serrate ; terminal segment
largest. Flowers yellow, turning whitish or purplish. Pods
necklace-shaped, with a long beak. A common weed eastward,
introduced from Europe.

VI. NASTURTIUM, R. Br.

Annual or biennial, mostly aquatic plants. Stems erect or
diffuse, often widely branching. Leaves simple, pinnately
lobed. Flowers small, white or yellow. Sepals spreading.
Stamens 1-6. Pod short and broad or nearly linear. Seeds
numerous in 2 rows in each cell.*

1. N. officinale, R. Br. WATERCRESS. Aquatic herbs. Stems
smooth, diffuse, rooting at the joints. Leaves with 3-9 rounded,
pinnate lobes, the terminal lobe much the largest. Racemes
elongating in fruit. Petals white, twice the length of the sepals.
Pods linear, £- ^ in. long, on slender, spreading pedicels. In ditches
and slow streams. Often used for salad.*

2. N. palustre, DC. YELLOW WATERCRESS. Annual or bien-
nial. Stem erect, branched, slightly downy. Leaves irregularly

DICOTYLEDONOUS PLANTS 97

lyrate, the lower petioled, the upper sessile. Flowers small. Petals
yellow. Pods linear, spreading, longer than the pedicels. In wet
places.*

VII. CARDAMINE, Tourn.

Annual or perennial. Rootstock often scaly or bulb-bear-
ing. Stem erect or ascending, usually smooth. Leaves
more or less divided. Flowers in terminal racemes, white or
purple. Petals rather large. Stamens 6. Fruit a linear
flattened pod. Seeds several, in a single row in each cell.*

1. C. rhomboidea, DC. BULBOUS CRESS. Perennial. Root tuber-
ous. Stem simple, erect, smooth, without runners, 9-18 in. tall.
Lower leaves long-petioled, ovate, orbicular or heart-shaped, often
angled or toothed, the upper short-petioled or sessile, lanceolate or
oblong, toothed or entire. Pedicels £-1 in. long. Petals white,
±-% in. long. Pod erect, linear-lanceolate, tipped by the persistent
style. Seeds round-oval. Cool, wet places.*

2. C. pennsylvanica, Muhl. BITTER CRESS. Annual. Stem slender,
erect, simple, or with a few slender branches, 6-15 in. tall. Leaves
mostly in a cluster at the base of the stem, pinnately divided, the
terminal lobe roundish, the lateral lobes narrower, somewhat hairy
above, stem-leaves nearly linear. Flowers small. Petals white,
longer than the sepals. Stamens 4. Pods linear, erect on erect
pedicels, about 1 in. long. Seeds oval. In wet places.*

Vffl. DENTARIA, Tourn.

Stems naked below, 2-3-leaved above, from a thickish,
more or less knotted or interrupted rootstock. Flowers
rather large, in early spring. Pod lance-linear, flattish. Seeds
in 1 row, wingless, seedstalks broad and flat.

1. D. diphylla, L. TWO-LEAVED TOOTH WORT, PEPPER ROOT,
CRINKLE ROOT. Rootstock long, often branched, toothed, eatable,
with a flavor like that of cress or radish. Stem-leaves 2, close
together, each composed of 3 ovate-diamond-shaped and toothed or
crenate leaflets ; the root-leaf like the stem-leaves. Flowers white.
Damp woods.

2. D. laciniata, Muhl. CROW'S FOOT. Rootstock short, necklace-
like. Stern-leaves 3-parted ; root-leaf often absent. Flowers white
or rose-color. Woods.

98 FOUNDATIONS OF BOTANY

IX. CAPSELLA, Medic.

Annual. Stem erect, downy, with branched hairs. Racemes
terminal, becoming elongated in fruit. Flowers small, white.
Pod obcordate or triangular, flattened contrary to the parti-
tion, shorter than the spreading pedicel.*

1. C. Bursa-pastoris, Moench. SHEPHERD'S PURSE. Root long and
straight. Stem branching above, downy below, smooth above.
Lower leaves forming a rosette at the base of the stem, irregularly
lobed or pinnately cut, stem-leaves lanceolate, clasping, toothed or
entire. Sepals downy, about ^ as long as the petals. Pod trian-
gular, notched, or cordate at the apex. Seeds several in each cell.
A common weed.*

X. ARABIS, L.

Annual or perennial herbs, smooth or with forked or star-
shaped hairs. Radical leaves spatulate ; stem-leaves sessile.
Flowers usually white. Petals entire, usually with claws.
Pods linear, flattened. Seeds often margined or winged.

1. A. hirsuta, Scop. A rough-hairy, erect, leafy-stemmed bien-
nial, 1-2 ft. high. Leaves simple ; stem-leaves oblong or lanceolate,
entire or toothed, somewhat clasping, often with an arrow-shaped
base. Flowers small, greenish-white, the petals somewhat longer
than the sepals. Pods and pedicels upright. Style almost wanting.
Seeds roundish, somewhat wing-margined. Rocks, N.

2. A. laevigata, Poir. A smooth, leafy-stemmed biennial 1-2 ft.
high, covered with a bloom. Stem-leaves lance-linear, clasping.
Flowers small and whitish, the petals hardly longer than the sepals.
Pods 2-3 in. long, flattened, spreading, and recurved. Seeds broadly
winged. Rocks.

3. A. canadensis, L. SICKLE POD. An upright, leafy-stemmed
biennial, 2-3 ft. high, simple or slightly branching above, some-
times slightly hairy at the base. Stem-leaves sessile, oblong-
lanceolate, pointed at both ends, downy, the lower ones toothed.
Flowers small, whitish, the petals twice as long as the sepals. Pods
scythe-shaped, much flattened, hanging from hairy pedicels. Seeds
broadly winged. Rocky hillsides.

XI. LOBULARIA, Desv. (ALYSSUM, L.)

Perennial, though usually growing as an annual. Stems
branching, diffuse; brandies slender. Leaves small, entire,

DICOTYLEDONOUS PLANTS 99

downy, with forked hairs. Flowers small, white, in numerous
terminal racemes. Petals obovate, entire, twice as long as
the sepals. Filaments enlarged below. Pod round, com-
pressed. Seeds 1 in each cell.*

1. L. maritima, Desv. SWEET ALYSSUM. Stem weak, diffuse,
ascending, minutely downy. Lower leaves narrowed into a petiole,
the upper sessile. Racemes erect, many-flowered. Flowers fra-
grant, pedicels ascending. Pod often pointed. Common in culti-
vation and often run wild.*

XH. MATTHIOLA, R. Br.

Herbaceous or shrubby oriental plants, covered with a down
composed of star-shaped hairs. Flowers in showy racemes
of many colors, ranging from white to crimson. Stigmas
large and spreading. Pods nearly cylindrical, except for a
prominent midrib on each valve.

1. M. incana, Br. COMMON STOCK, GILLYFLOWER. Biennial or
perennial, with somewhat woody stems. Cultivated in greenhouses
and gardens.

40. CAPP ARID ACE JE. CAPER FAMILY.

Herbs (when growing in cool temperate regions), with bit-
ter or nauseous juice. Leaves alternate, usually palmately
compound. Flowers often irregular, usually perfect. Sepals
4-8. Petals 4 or wanting. Stamens 6 or more. Ovary and
pod 1-celled, with 2 rows of ovules. Seeds kidney-shaped.

I. POLANISIA, Raf.

Ill-smelling annual plants covered with glandular or
clammy hairs. Sepals distinct, spreading. Petals with
claws, notched at the tip. Stamens 8-32, of various lengths.
Receptacle not lengthened. Pod linear or oblong, rather
large, many-seeded.

1. P. graveolens, Raf. A very strong-scented, leafy, branching
herb, 6-15 in. high. Leaves with 3 oblong leaflets. Flowers small,
pinkish and yellowish-white, in the axils of leafy bracts, in terminal
racemes. Stamens 8-12, not much longer than the petals. Pod
about 2 in. long, slightly stalked. Gravelly banks.

100 FOUNDATIONS OF BOTANY

H. CLEOME, L.

Mostly annual herbs ; stems branched. Leaves petioled,
simple, or with 3-7 entire or serrate leaflets. Flowers in
bracted racemes. Sepals 4, often persistent. Petals 4, often
long-clawed, nearly equal, entire. Stamens 6, filaments
thread-like, usually projecting much, but sometimes 1-3 much
shorter than the others, inserted on the short receptacle.
Ovary on a short stalk with a small gland at its base. Fruit
a slender capsule on an elongated stalk.*

1. C. integrifolia, Ton. and Gr. ROCKY MOUNTAIN BEE PLANT.

A smooth plant 2 ft. or more high. Leaves with 3 leaflets. Flowers
pink, showy, in leafy-bracted racemes. Pod oblong to linear, 1-2 in.
long. Cultivated as an ornamental plant and also for bees. Common
in a wild condition "W.

41. RESEDACE.3L. MIGNONETTE FAMILY.

Annual or perennial herbs, rarely shrubs. Leaves alter-
nate, simple or pinnately cut. Flowers racemed or spiked,
bracted. Calyx 4-7, parted, often irregular. Petals 4-7,
hypogynous, often unequal and cleft or notched. Stamens
usually many, borne on a large one-sided hypogynous disk.
Ovary of 2-6 carpels, which are more or less united into a
single 1-celled, many-seeded, several-lobed, or horned pistil,
which opens at the top before the seeds ripen.

RESEDA, Tourn.

Annual ; stems diffuse, widely branched. Leaves sessile,
entire or lobed, smooth. Flowers in close racemes or spikes.
Petals 4-7, toothed or cleft. Stamens 8-30, inserted at one
side of the flower. Capsule 3-6-lobed.*

1. R. odorata, L. MIGNONETTE. Stem widely diffuse, 6-12 in.
high, smooth. Leaves wedge-shaped, entire or 3-lobed. Flowers
small, greenish-yellow, very fragrant. Petals deeply 7-13-cleft.
Often cultivated. From Egypt.*

DICOTYLEDONOUS PLANTS 101

42. SARRACENIACE^). PITCHER-PLANT FAMILY.

Perennial, stemless, marsh, herbs. Leaves tubular or
trumpet-shaped. Flowers single, nodding, on a naked or
bracted scape. Sepals 4-5, colored, persistent. Petals 5,
deciduous, or sometimes wanting. Stamens numerous. Pistil
compound, 5-celled, many-ovuled ; style terminal, nearly as

broad as the flower, shield-shaped.*

SARRACENIA, Tourn.

Rootstock short, horizontal ; scape naked. Leaves trumpet-
shaped, with a wing extending nearly to the base and a broad
blade at the apex (see Part II, Ch. XXVI) ; tube hairy
within, with downward-pointing, stiff hairs. Calyx 3-bracted.
Petals obovate, 'drooping or incurved. Style umbrella-shaped,
5-angled ; stigmas at the hooked angles of the style on the
under surface. Capsule globose, rough. [The tubular leaves
usually contain more or less water and dead insects, the latter
having been attracted by a honey-like secretion near the
opening. For a full account of the structure and peculiar
action of the leaves, see Goodale's Physiological Botany,
pp. 347-353.]*

1. S. purpurea, L. SIDE-SADDLE FLOWER. Leaves ascending,
curved, broadly winged, purple-veined, 4-8 in. long; blade erect,
round-cordate, hairy on the inner side. Scapes 12-18 in. tall ; flower
deep purple, about 2 in. broad. Style yellowish. Mossy swamps.*

43. SAXIFRAGACE^E. SAXIFRAGE FAMILY.

Herbs or shrubs. Leaves alternate or opposite, generally
without stipules. Sepals 4 or 5, more or less coherent with
each other and adnate to the ovary. Petals as many as the
sepals and alternate with them. Stamens as many as the
petals and alternate with them, or 2-10 times as many.
Ovary usually of 2 carpels, united only at the base or more
or less throughout. Fruit generally a 1-2-celled capsule,
sometimes a berry. Seeds many, with endosperm.

102 FOUNDATIONS OF BOTANY

I. SAXIFRAGA, L.

Herbs with, simple or palmately cut leaves and generally
cymose or panicled flowers. Sepals 5, more or less united.
Petals 5, entire, inserted on the calyx-tube. Stamens 10.
Capsule consisting of 2 (sometimes more) ovaries, united at
the base, separate and diverging above.

1. S. virginiensis, Michx. EARLY SAXIFRAGE, MAYFLOWER.
Perennial. Stemless, with a cluster of spatulate, obovate, or wedge-
shaped root-leaves and a scape 3-9 in. high, which bears a dense
cluster of small white flowers, becoming at length a panicled cyme.
Petals white, oblong, much longer than the calyx. Rocks and dry
hillsides N.

2. S. pennsylvanica, L. SWAMP SAXIFRAGE. Perennial.
Leaves 4-8 in. long, oblong-lanceolate and tapering to the base,
slightly toothed. Scape 1-2 ft. high, bearing an oblong cluster of
small greenish flowers, at length diffusely panicled. Petals green-
ish-yellow (rarely crimson), linear-lanceolate, hardly longer than the
calyx-lobes. Boggy ground.

II. TIARELLA, L.

Perennial. Flowers white, in racemes. Calyx white,
5-parted, nearly free from the ovary. Corolla of 5 very nar-
row petals, with slender claws, alternating with the calyx-
lobes. Stamens 10, springing from the calyx-tube arid
extending outside the flower. Styles 2, long and slender.
Ovary 1-celled, 2-beaked. In fruit one of the carpels grows
to be much larger than the other, thus making up the main
bulk of the thin, dry pod, which has a few seeds attached
near the bottom.

1. T. cordifolia, L. FALSE MITRE-WORT. Stem 5-12 in. high,
usually leafless, sometimes with 1 or 2 leaves. Rootstock bearing
runners in summer. Leaves heart-shaped, sharply lobed, the lobes
with acute or mucronate teeth, somewhat hairy above, downy
beneath. Raceme short and simple. Rocky woods, especially N.

IH. MITELLA, Tourn.

Delicate perennial herbs. Flowers small, pretty, in a sim-
ple raceme or spike. Calyx 5-cleft, adnate to the base of the

DICOTYLEDONOUS PLANTS 103

ovary. Petals 5, cut-fringed, inserted on the throat of the
calyx-tube. Stamens 5 or 10, not projecting from the calyx-
tube. Styles 2, very short. Ovary and pod 2-beaked,
globular, 1-celled.

1. M. diphylla, L. TWO-LEAVED BISHOP'S CAP, FRINGE CUP,
FAIRY CUP. Stemless, with long-petioled, roundish-cordate root-
leaves, and a scape about 1 ft. high, bearing 2 opposite, nearly ses-
sile leaves. Flowers many, racemed, white. Woods.

IV. HEUCHERA, L.

Perennials with a tall scape and roundish, heart-shaped
radical leaves. Flowers rather small, greenish or purplish,
in a long panicle. Calyx 5-cleft, the tube below adnate to the
ovary. Petals 5, small, spatulate, inserted with the 5 sta-
mens on the margin of the calyx-tube. Capsule 1-celled,
2-beaked, splitting open between the beaks.

1. H. americana, L. COMMON ALUM ROOT. Scapes 2-4 ft. high,
rather slender, often several from the same root, hairy and glandu-
lar. Radical leaves large and long-petioled, abundant, somewhat
7-lobed. Flowers whitish with a tinge of purple, in a loose panicle.
Stamens projecting considerably outside the flower, their stamens
of a bright terra cotta color. The root is very astringent and is
somewhat used as a home remedy. Shaded banks, fence rows, and
thickets ; common W.

V. PHILADELPHUS, L.

Shrubs. Leaves simple, opposite, 3-5-ribbed, petioled,
without stipules. Flowers solitary or in cymes, large, white.
Calyx-tube top-shaped, adnate to the ovary, the limb 4-5-
parted, persistent. Petals 4-5, rounded or obovate. Stamens
20-40, shorter than the petals. Ovary 3-5-celled, many-
seeded ; styles 3-5, more or less united.*

1. P. grandiflorus, Willd. LARGE-FLOWERED SYRINGA. Shrub,
6-10 ft. high; branches downy. Leaves ovate or ovate-oblong,
taper-pointed, sharply serrate, downy, 3-ribbed. Flowers solitary or
2—3 together, white, 1^-2 in. broad, not fragrant. Calyx-lobes
ovate, taper-pointed, about twice as long as the tube. On low
ground, S., and cultivated.*

2. P. coronarius, L. GARDEN SYRINGA. Shrub, 8-10 ft. high.
Leaves oval or ovate, obtuse at the base, acute at the apex, remotely

104 FOUNDATIONS OF BOTANY

toothed, smooth above, downy beneath. Flowers in terminal
racemes, creamy white, 1-1^ in- wide, very fragrant. Calyx-lobes
ovate, acute, longer than the tube. Common in cultivation.*

VI. DEUTZIA, Thunb.

Shrubs with simple, opposite leaves, without stipules.
Flowers all perfect and alike, racemed or panicled, showy.
Calyx-lobes 5. Petals 5. Stamens 10, 5 long and 5 short ;
filaments flat and 3-pronged, the middle prong bearing an
anther. Styles 3-5, slender. Pod 3-5-celled.

1. D. gracilis, Sieb. and Zucc. About 2 ft. high, loosely spreading.
Leaves ovate-lanceolate, sharply serrate, smooth. Flowers white,
very numerous. Cultivated from Japan, often in greenhouses.

VH. RIBES, L.

Shrubs. Leaves palmately veined and lobed, sometimes
with stipules. Calyx-tube egg-shaped, adnate to the 1-celled
ovary, its 5 lobes usually colored like the petals. Petals 5,
small, generally inserted on the throat of the calyx-tube.
Stamens 5, inserted with the petals. Styles 2. Ovary
1-celled, with 2 placentse on its walls, becoming in fruit a
pulpy (usually eatable) berry.

1. R. rotundifolium, Michx. SMOOTH WILD GOOSEBERRY. Spines
few and short, prickles few or absent. Leaves roundish, lobed, with
the lobes crenate-dentate, often downy. Peduncles slender ; flowers
inconspicuous. Calyx-lobes reflexed. Styles and stamens projecting
decidedly from the calyx-tube. Berries smooth.

2. R. Cynosbati, L. PRICKLY WILD GOOSEBERRY. Spines in
pairs. Leaves long-petioled, downy, heart-shaped, cut-dentate. The
single style and the stamens not projecting from the calyx-tube.
Berries generally prickly, brownish-purple, pleasant-flavored.

3. R. rubrum, L. RED CURRANT. Stems more or less reclining.
Leaves somewhat heart-shaped, obtusely 3-5-lobed. Racemes droop-
ing. Limb of the calyx wheel-shaped. Berries acid, eatable, red
or light amber-colored. Cultivated from Europe, also a variety wild
in the northern United States.

4. R. aureum, Pursh. GOLDEN CURRANT, FLOWERING C., MIS-
SOURI C., CLOVE C. A much taller shrub than the common red
currant. Leaves 3-lobed, toothed. Racemes short and loose. Tube

DICOTYLEDONOUS PLANTS 105

of the yellow calyx much longer than its limb. Flowers very
fragrant. Fruit brownish-black, barely eatable.

44. PLATANACE^. SYCAMORE FAMILY.

Trees ; with simple, alternate, petioled leaves with stipules,
the bases of the petioles covering the buds. Flowers monoe-
cious, in axillary, long-peduncled, globose heads. Calyx and
corolla very inconspicuous, each consisting of 3-8 minute
scales, or wanting. Stamens as many as the sepals and
opposite them. Pistils several, inversely conical, hairy at
the base, styles long. Capsules 1-seeded.*

PLATANUS, L.

Characters of the family.

1. P. occidentalis, L. SYCAMORE, BUTTONWOOD. A large tree,
bark light-colored, smooth, peeling off in large, thin plates. Leaves
large, round heart-shaped, angularly lobed and toothed, densely
white-woolly when young, becoming smooth with age ; stipules
large, toothed. Fruit in a globular, drooping head, which remains
on the tree through the winter, dropping the seeds very slowly.
Common on river banks and in swampy woods.*

45. ROSACEJE. ROSE FAMILY.

Herbs, shrubs, or trees. Leaves alternate or rarely oppo-
site, simple or compound, with stipules. Calyx 5-lobed.
Petals 5, rarely wanting, inserted with the stamens on the
edge of a disk that lines the calyx-tube. Stamens many,
rarely 1 or few. Carpels 1 or more, distinct or coherent, free
or adnate to the calyx-tube. Fruit a pome, a stone-fruit or
group of stone-fruits, or 1-several akenes or follicles, rarely
a berry or capsule. The relation of the parts of the flower
to each other and to the receptacle is shown in Fig. 13.

106

FOUNDATIONS OF BOTANY

Ripe carpels not enclosed within the calyx-tube.

1. Fruit dry.

(a) Carpels 1-5, inflated. Physocarpus, I.

(b) Pods 5-8, not inflated. Spiraea, IT.

Waldsteinia, VIII.

(e?) Akenes many, on a dry receptacle. Styles not length-
ening. Potentilla, X,
(e) Akenes many, on a dry receptacle. Styles lengthening-
after flowering, forming tails to the akenes.

Geum., XI.

2. Fruit fleshy.

(a) Akenes several-many, becoming little stone-fruits.

Rubus, VII.

(b) Akenes many, dry on ripening, on a fleshy, eatable

receptacle. Fragaria, IX.

A B C .

FIG. 13. — Pistils in the Rose Family.
A, Prunus-type ; B, Potentilla-type ; C, Rosa-type, c, calyx, o, ovary.

Ripe carpels enclosed ivithin the calyx-tube.
1. Fruit a pome.

(a) Carpels more than 2-seeded ; seeds covered with a muci-
laginous pulp. Fruit 5-celled. Cydonia, III.

DICOTYLEDONOUS PLANTS 107

(6) Carpels 2-seeded (except in some cultivated varieties) ;

seeds without pulp. Fruit 5-celled. Pyrus, IV.

2. Fruit not evidently a pome or not at all so.

(a) Trees or shrubs. Fruit appearing like a stone-fruit, with
a stone usually of 2-5 bony 1-seeded carpels united.

Cratsegus, VI.

(6) Herbs. Fruit consisting of numerous very small akenes

collected on a fleshy, eatable receptacle. Fragaria, IX.

cherry). Prunus, XIII.

I. PHYSOCARPUS, Maxim.

Shrubs. Leaves simple, palmately veined and lobed, pet-
ioled. Flowers white, in terminal corymbs. Calyx spreading,
5-lobed. Petals 5. Stamens numerous. Pistils 1-5, short-
stalked, stigma terminal ; ovaries becoming inflated at matu-
rity, 2-4-seeded, splitting open.*

1. P. opulifolius, Maxim. NINEBARK. A spreading shrub 3-6 ft.
high, the old bark separating into thin strips. Leaves petioled,
broadly ovate or rounded, often heart-shaped, 3-lobed, the lobes doubly
crenate-serrate ; stipules deciduous. Corymbs terminal, peduncled,
nearly globose, downy, many-flowered. Pedicels, and calyx nearly
smooth. Follicles 3-5, much longer than the calyx, smooth and
shining, obliquely tipped by the persistent style. Banks of streams,
and often cultivated.*

H. SPIREA, L.

Shrubs with simple leaves. Flowers perfect, in terminal
or axillary racemes or panicles. Calyx 5-cleft, persistent.
Petals 5. Stamens numerous. Pistils usually f>, free from
the calyx and alternate with its lobes. Follicles not inflated,
2-several-seeded.*

1. S> salicifolia, L. WILLOW-LEAFED SPIREA. Shrubs 2-5 ft.
high, branches smooth ; leaves lanceolate to oblong-ovate, smooth
or nearly so, sharply serrate, base usually wedge-shaped, pale beneath ;
stipules deciduous ; flowers white or pink, panicle dense-flowered ;
follicles smooth. On low ground.*

108 FOUNDATIONS OF BOTANY

2. S. reevesiana, Card. BRIDAL WREATH. Shrubs 2-4 ft. tall ;
branches long, slender, and spreading ; leaves lanceolate, serrate,
sometimes 3-lobed or pinnatifid, with a bloom beneath ; flowers white
or pinkish, in axillary racemes or corymbs, often forming long
wreaths ; follicles smooth. Cultivated from Europe.

3. S. tomentosa, L. HARDHACK. Erect shrubs ; stems densely
downy, usually simple; leaves simple, ovate or oblong, serrate,
densely rusty downy below, smooth and dark green above ; flowers
small, pink or purple, in a close panicle ; follicles 5, densely downy,
several-seeded. On low ground S., and along fence-rows and in pas-
tures N., where it is a troublesome weed.*

III. CYDONIA.

Trees or shrubs. Leaves simple, toothed or lobed, stipules
deciduous. Flowers usually solitary, white or pink. Calyx-
tube urn-shaped, adnate to the ovary, 5-lobed, lobes acute,
spreading, persistent. Petals 5. Stamens numerous, inserted
with the petals on the calyx-tube. Styles 2-5, mostly 5,
united at the base. Ovary 5-celled, seeds many in each cell.
Fruit a pome, globose, usually depressed or hollowed at the*
extremities, flesh without hard grains.*

1. C. vulgaris, Pers. QUINCE. Shrub 6-12 ft. high. Leaves
oblong-ovate, acute at the apex, obtuse at the base, entire, downy
below. Flowers large, white or pink. Fruit ovoid, downy. Cul-
tivated.*

2. C. japonica, Pers. JAPAN QUINCE. A widely branching
shrub, 3-6 ft. high, branches with numerous straight spines. Leaves
ovate-lanceolate, acute at each end, smooth and shining, serrulate ;
stipules conspicuous, kidney-shaped. Flowers in nearly sessile axil-
lary clusters, bright scarlet. Fruit globose. Common in cultivation.*

IV. PYRUS, L.

Trees. Leaves simple, stipules small, deciduous. Flowers
in cymes, large, white or pink. Calyx urn-shaped, adnate to
the ovary, 5-cleft, its lobes acute. Petals rounded, short-
clawed. Stamens numerous, borne with the petals on the
calyx-tube. Styles 5, distinct or slightly united at the base.
Fruit a pome, with about 2 seeds in each carpel.*

1. P. communis, L. PEAR. A tree, often very large, head usually
pyramidal j branches often thorny. Leaves thick and leathery,

DICOTYLEDONOUS PLANTS 109

ovate or oval, acute, finely serrate or entire, downy when young,
becoming smooth with age ; petioles slender. Cymes few— several-
flowered, terminal, and at the ends of "fruit spurs" grown the
previous season. Flowers white. Styles not united. Fruit obovoid,
with hard gritty grains near the core. A European and Asiatic
tree common in cultivation.*

2. P. Malus. APPLE. A tree with a rounded top and dark-
colored bark. Leaves oval or ovate, obtuse or pointed, dentate or
nearly entire, rounded at the base, smooth above, downy beneath.
Cymes few— many-flowered. Flowers large, white or pink. Calyx
downy. Fruit depressed-globose to ovoid, hollowed at the base and
usually at the apex. Cultivated from Europe and often running
wild .in old pastures, etc., E.*

3. P. coronaria, L. AMERICAN CRAB APPLE. A small tree
with smooth bark. Leaves triangular or oval-lanceolate, acutish or
rounded or a little heart-shaped at the base, cut-serrate and often
somewhat 3-lobed, slender-petioled, soon smooth. Flowers large,
few in a cluster, pale rose-color, very sweet-scented. Fruit bright
green, turning yellowish, sometimes 1£ in. in diameter, flattened at
right angles to the pedicels, very fragrant. Glades, W. N. Y., West
and South.

4. P. angustifolia, Ait. NARROW-LEAVED CRAB APPLE. A small
tree with smooth, light gray bark. Leaves lanceolate or oblong,
serrate, downy when young, acute at the base, short-petioled.
Corymbs few-flowered. Flowers pink, fragrant, about 1 in. broad.
Styles smooth, distinct. Fruit nearly globose, about f in. in diame-
ter, very sour. In open woods, Penn., W. and S.*

5. P. arbutifolia, L. f. CHOKEBERRY, CHOKE PEAR, DOGBERRY.
A shrub 5-8 ft. high. Leaves oblong or oblanceolate, finely serrate,
downy beneath, short-petioled. Flowers in a downy compound
cyme, small, white or reddish. Fruit pear-shaped or nearly globular,
not larger than a currant, very dark purple, dry and puckery. There
is also a smooth-leaved variety with black fruit. Swamps and damp
thickets, especially N. E.

6. P. americana, DC. AMERICAN MOUNTAIN ASH. A tall shrub
or small tree. Leaves odd-pinnate. Leaflets oblong-lanceolate, taper-
pointed, sharply serrate, smooth, bright green. Flowers small, white,
in large, flat, compound cymes. Fruit bright scarlet, not larger
than currants. Common N. and often cultivated.

7. P. Aucuparia, Gaertn. EUROPEAN MOUNTAIN ASH OR ROWAN
TREE. Larger than No. 6. Leaflets paler, downy beneath. Fruit
larger, about £ in. in diameter. Cultivated from Europe.

110 FOUNDATIONS OF BOTANY

V. AMELANCHIER, Medic.

Shrubs or small trees with smooth gray bark. Leaves
simple, sharply serrate, petioled. Flowers white, in racemes.
Calyx-tube 5-cleft, adnate to the ovary. Petals oblong.
Styles 5, united below. Ovary 5-celled, 2 ovules in each cell,
often only 1 maturing. Fruit small, berry-like.*

1. A. canadensis, Torr. and Gr. SERVICE BERRY, JUNE BERRY,
SHAD BUSH, SUGAR PLUM, SUGAR PEAR, WILD PEAR. A small
tree, branches downy when young, soon becoming smooth. Leaves
ovate to elliptical, finely and sharply serrate, acute at the apex,
usually obtuse or cordate at the base. Racemes slender, many-
flowered, appearing before or with the leaves. Flowers showy.
Petals 4 or 5 times the length of the smooth sepals. Fruit globose,
dark red, edible. In rich woods ; extremely variable in height, and
in shape of leaves.*

VI. CRATJEGUS, L.

Shrubs or small, trees, mostly with numerous strong spines,
wood very hard. Leaves serrate, lobed or deeply incised,
petioled. Flowers white or pink, in terminal corymbs or
sometimes solitary. Calyx-tube urn-shaped, 5-cleft, the limb
persistent. Petals round. Stamens few or many. Styles
1-5, distinct ; ovules 1 in each cell. Fruit a small pome with
bony carpels.* [The species are hard to distinguish and are
not very perfectly denned. At present the genus is under-
going a careful revision by Professor C. S. Sargent.]

1. C. coccinea, L. SCARLET-FRUITED THORN, RED HAW. A tall
shrub or small tree, with smooth, reddish branches, but the young
shoots downy. Leaves thin, roundish-ovate, cut-lobed or sharply
toothed, slender-petioled. Flowers large, in a many-flowered corymb.
Fruit bright red, nearly globular or obovoid, ^ in. long.

Var. mollis, Torr. and Gr., has the young shoots densely covered
with down and fruit twice the length of the preceding, sweet and
^edible. Common in the Mississippi valley.

2. C. tomentosa, L. PEAR THORN. A small tree, the young-
shoots, peduncles, and calyx downy or soft-hairy. Leaves large,
thickish, ovate or ovate-oblong, downy beneath, doubly serrate or
cut-lobed. Flowers later than No. 1, sometimes 1 in. in diameter.
Fruit scarlet or orange, rather less than 1 in. long, edible.

3. C. Crus-Galli, L. COCKSPUR THORN. Small trees with spread-
ing branches ; spines usually numerous, long and stout, but some-

DICOTYLEDONOUS PLANTS 111

times few or wanting. Leaves thick, oval or obovate, shining above,
paler below, obtuse or acute, and sharply serrate at the apex, wedge-
shaped and entire at the base. Corymbs terminal, many-flowered,
smooth; flowers about £ in. wide; styles 1-3 ; fruit red, subglobose,
^ in. in diameter. Common in open woods.*

4. C. spathulata, Michx. SMALL-FRUITED HAW. A small tree,
young twigs densely downy ; spines 1-2 in. long ; leaves small,
spatulate, crenate at the rounded apex, entire and wedge-shaped
below, leathery, smooth ; stipules crescent-shaped ; corymbs com-
pound, many-flowered ; flowers small ; calyx-lobes very short ; styles
5 ; fruit red, about the size of a small pea. On river banks.*

5. C. flava, Ait. YELLOW HAW. A small tree with very numer-
ous spines ; leaves obovate, glandular-serrate at the rounded apex,
cuneate below, downy when young ; petiole short ; corymbs few-
flowered, slightly downy ; flowers ^-f in. wide ; calyx-lobes entire
or glandular-serrate ; styles 4-5 ; fruit pear-shaped, £ in. or more in
length, greenish-yellow. On sandy soil.*

vn. RUBUS, L.

Mostly prickly shrubs, producing runners. Leaves alter-
nate, simple or compound ; stipules adnate to the petiole.
Flowers in terminal and axillary clusters, rarely solitary,
white (in one American species [No. 1] purple rose-color).
Calyx free from the ovary, with a broad tube ; its lobes 5,
persistent. Petals 5. Stamens many. Carpels many, distinct,
on a convex receptacle. Fruit a cluster of little 1-seeded
stone-fruits on a dry or somewhat juicy receptacle.

A. RASPBERRIES.

Grains of the fruity when ripe, falling off from the receptacle and
leaving the latter with the calyx.

1. Rubus odoratus, L. FLOWERING RASPBERRY (often wrongly
called MULBERRY). Stems shrubby and rather stout, 3-5 ft. high,
not prickly, the young shoots, peduncles, and calyx covered with
sticky glandular hairs. Leaves large, simple, 3-5-lobed. Flowers
showy, rose-purple, 1-2 in. in diameter, on many-flowered pedun-
cles. Fruit flattish, eatable. Rather common E. and N. and often
cultivated.

2. R. triflorus, Richardson. DWARF RASPBERRY (also wrongly
known as MULBERRY). A slender trailing plant, almost entirely
herbaceous, not prickly but sometimes bristly. Leaves compound,

112 FOUNDATIONS OF BOTANY

usually of 3 but sometimes of 5 thin ovate-lanceolate, frequently
unsymmetrical leaflets, which are coarsely doubly serrate and often
cleft or lobed, with a shining upper surface. Flowers small, on 1-3-
flowered peduncles. Fruit of a few loosely cohering grains, eaten
by children. Common, especially N.t in hilly woods, often forming
a dense carpet in the partial shade of pines.

3. R. occidentalis, L. BLACK RASPBERRY. Stems long and
slender, often recurved and rooting at the tips, armed with weak,
hooked prickles. Leaves petioled, 3-5 ovate leaflets, coarsely ser-
rate, white-downy below. Flowers white, in compact terminal
corymbs. Pedicels erect or ascending. Fruit black, hemispherical,
separating easily from the receptacle. Common on borders of
woods Mo. and N., widely cultivated.*

4. R. strigosus, Michx. RED RASPBERRY. Stems widely branch-
ing, biennial, not rooting at the tips, armed with weak bristles and
with a few hooked prickles. Leaves petioled, of 3—5 ovate leaflets
which are sharply serrate and sometimes lobed, downy beneath.
Flowers in terminal and axillary racemes and panicles, pedicels
drooping. Fruit hemispherical or conical, red, separating easily
from the receptacle. Common on mountains i»nd burned clearings.
Iowa and N. and widely cultivated.*

B. BLACKBERRIES.

Grains of the ripe fruit falling from the calyx along with the soft,
eatable receptacle.

5. R. nigrobaccus, Bailey. HIGH BLACKBERRY. Stem shrubby,
erect or bending, 4-10 ft. high, glandular-downy above and with
stout, hooked prickles below. Leaves petioled, of 3—7 ovate leaflets
which are acute, irregularly serrate, smooth or soft-hairy. Flowers
in terminal, bracted panicles. Petals white, obovate, much longer
than the taper-pointed sepals. Fruit large, black, oblong. Common
in thickets.*

6. R. villosus, Ait. Low BLACKBERRY, DEWBERRY. Stems
shrubby, trailing widely, from 3-10 ft. long, somewhat prickly.
Leaflets usually 3, but sometimes 5 or 7, ovate, acute, sharply (and
doubly) cut-serrate, thin. Racemes upright on the short branches,
1-3-flowered. Fruit roundish, of fewer and larger grains than No. 5,
very sweet when fully ripe. Common N"., in stony or gravelly fields.

7. R. cuneifolius, Pursh. SAND BLACKBERRY. Stem shrubby,
erect or diffuse, 2-3 ft. high ; prickles straight or recurved. Leaves
petioled, 3-5-foliate ; leaflets obovate, serrate towards the apex,
wedge-shaped towards the base, rough above, white downy-woolly
beneath. Racemes mainly terminal, few-flowered. Petals white,

DICOTYLEDONOUS PLANTS 113

longer than the sepals. Fruit ovoid, black, smaller than the pre-
ceding. Common in old fields.*

8. R. hispidus, L. Stem trailing or prostrate, often several feet
in length, armed with small, straight, or recurved prickles, and
often thickly set with bristles. Leaves petioled, mostly of 3 leaflets ;
leaflets obovate, obtuse, rather coarsely serrate. Flowering branches
commonly erect, few-flowered, flowers white. Fruit black. Common
on dry, sandy soil.*

VIII. WALDSTEINIA, Willd.

Stemless perennial herbs. Leaves 3-5-lobed or divided.
Flowers several, rather small, yellow, on a bracted scape.
Calyx-tube top-shaped; the limb spreading, with sometimes
little bracts alternating with the lobes. Petals 5. Stamens
many. Style 2-6. Akenes few, on a dry receptacle.

1. W. fragarioides, Tratt. BARREN STRAWBERRY. A low herb
with much the appearance of a strawberry plant. Leaflets 3,
broadly wedge-shaped, crenate-dentate. Scapes many-flowered ; the
flowers rather pretty. Wooded hillsides.

IX. FRAGARIA, Tourn.

Perennial scape-bearing herbs, with runners. Leaves with
3 leaflets ; stipules adnate to the petiole. Flowers (of Ameri-
can species) white. Calyx free from the ovary, 5-parted,
5-bracted, persistent. Petals 5. Stamens many. Carpels
many, on a convex receptacle. Akenes of the ripe straw-
berry many, very small, more or less imbedded in the large,
sweet, pulpy receptacle.

1. F. virginiana, Mill. WILD STRAWBERRY. Leaflets thick,
oval to obovate, coarsely serrate, somewhat hairy. Scape usually
shorter than the petioles, few-flowered. Fruit ovoid, akenes imbedded
in deep pits. Common.*

2. F. vesca, L. EUROPEAN STRAWBERRY. Leaflets ovate or
broadly oval, dentate above, wedge-shaped below, slightly hairy.
Scape usually longer than the petioles. Fruit globular or oval,
akenes adherent to the nearly even surface of the receptacle. Com-
mon in cultivation. Many of the cultivated varieties of strawberry
are hybrids between the two described above. The American form
is less hairy than the European and is by some regarded as distinct.*

114 FOUNDATIONS OF BOTANY

X. POTENTILLA, L.

Perennial herbs, rarely shrubs. Leaves compound ; stipules
adnate to the petiole. Flowers white or yellow, rarely red ;
solitary or in cymes. Calyx free from the ovary, 5-cleft, with
5 little bracts alternating with its lobes. Petals 5. Stamens
many. Carpels usually many, on a dry convex or concave
receptacle ; styles falling off from the akenes as they mature.

1. P. arguta, Pursh. UPRIGHT CINQUEFOIL. An erect, stout
hairy plant, 1-4 ft. high. Root-leaves long-petioled, pinnate. Stem-
leaves few, each of 3-7 leaflets, the latter broadly ovate and cut-
toothed or serrate, downy underneath. Flowers large, in dense
terminal clusters ; the petals whitish or cream-cplor. Rocky hills.

2. P. canadensis, L. COMMON CINQUEFOIL. Stems slender, pro-
cumbent, silky-hairy, sending out long runners. Leaflets obovate
wedge-shaped, appearing like 5 from the divisions of the 2 lateral
ones. Peduncles 1-flowered in the axils of the leaves. Flowers
yellow. Common in dry pastures and a troublesome weed.

3. P. argentea, L. SILVERY CINQUEFOIL. Stems prostrate or
ascending and branching, woolly. Leaflets oblong, wedge-shaped,
those of the upper leaves very narrow, with a few large, deeply cut
teeth, smooth and green above, silvery beneath, with a dense coat of
white wool. Flowers small and somewhat clustered, yellow. Dry
fields and roadsides.

XL GEUM, L.

Erect perennial herbs. Radical leaves crowded, pinnate,
with a very large terminal leaflet. Flowers and fruit much
as in Potentilla, but the akenes tailed with the remains of the
styles.

1. G. album, Gmelin. WHITE AVENS. Stem erect, branching
above, smooth or finely downy, 18-24 in. high. Radical leaves pin-
nate, or the earliest simple and rounded, long-petioled, serrate or
dentate, terminal lobe larger than the lateral lobes; stem-leaves
short-petioled, 2-5-lobed or parted. Flowers on slender peduncles.
Petals white, not longer than the sepals. Styles jointed near the
middle, the lower portion persistent and hooked. Ovaries and recep-
tacle hairy, head of fruit globose. Rich woods.*

2. G. virginianum, L. Stem 2-3 ft. high, stout and bristly
hairy. Lower leaves and root-leaves pinnate, varying greatly; upper
leaves mostly of 3 leaflets or 3-parted. Petals white or pale yellow,

DICOTYLEDONOUS PLANTS 115

small, shorter than the calyx-lobes. Pleads of fruit large, on stout,
hairy peduncles ; the receptacle nearly or quite smooth. Borders of
woods and damp thickets.

3. G. rivale, L. WATER AVENS, PURPLE AVENS, CHOCOLATE
ROOT. Stem l£-2 ft. high, somewhat downy or hairy, simple or
nearly so. Root-leaves lyrate and somewhat pinnate, with the divi-
sions irregular ; stem-leaves few, of 3 leaflets or 3-lobed. Flowers
rather large. Petals purplish-yellow, as long as the brownish-purple
calyx -lobes. Styles long, purplish ; stigmas thread-like, feathered
with soft hairs, especially in fruit. Wet meadows.

XII. ROSA, Tourn.

Erect, running or climbing prickly shrubs. Leaves pinnate,
leaflets serrate, stipules adnate to the petiole. Calyx-tube
urn-shaped, with a rather narrow mouth. Petals (in single
roses) 5. Stamens many, inserted around the inside of the
mouth of the calyx-tube. Ovaries many, hairy, ripening
into bony akenes, enclosed in the rather fleshy and sometimes
eatable calyx-tube.

1. R. blanda, Ait. EARLY WILD ROSE. Steins 1-3 ft. high,
usually without prickles ; stipules broad. Flowers generally large,
corymbed or solitary ; sepals after flowering closing over the mouth
of the calyx-tube and persistent. Rocks and rocky shores.

2. R. Carolina, L. SWAMP ROSE. Stems 4-8 ft. high, with
stout and generally recurved prickles. Stipules long and narrow ;
leaflets commonly downy beneath, finely serrate. . Flowers several in
a corymb, bright rose-color. Sepals spreading and falling off after
flowering. Damp woods and borders of swamps.

3. R. lucida, Ehrh. DWARF WILD ROSE. Stems varying in
height from less than a foot to 6 ft., with stout, somewhat hooked
prickles. Stipules rather broad ; leaflets small, thickish and glossy
above, coarsely toothed toward the tip. Flowers corymbed, or soli-
tary, pale rose-color. Sepals spreading and falling off after flower-
ing. Moist ground and swamps.

4. R. humilis, Marsh. PASTURE ROSE. Stem erect, branched,
usually armed with stout stipular prickles and with bristles, but
sometimes nearly smooth, 1-3 ft. tall. Leaves mostly of 5 leaflets ;
stipules entire; leaflets oblong-lanceolate or oval, shining above,
pale beneath, sharply serrate. Flowers solitary or 2-3 together,
2-3 in. broad, pink. Peduncles and calyx glandular-downy. Calyx-
lobes leaf-like, spreading, finally deciduous. Styles distinct. Fruit
globose, bristly hairy. On dry soil ; our most common wild rose. S.*

116 FOUNDATIONS OF BOTANY

5. R. rubiginosa, L. SWEETBRIER. Stem erect or curving,
armed with stout recurved prickles. Leaves with 5-7 leaflets, the
latter broadly oval, coarsely serrate, glandular-bristly beneath,
aromatic. Flowers white or pink. Sepals widely spreading,
deciduous. Fruit obovate, slightly bristly. Common in cultiva-
tion and sometimes wild.*

XIH. PRUNUS, Tourn.

Trees or shrubs. Leaves simple, with stipules, which are
often small or fall off early. Calyx with a bell-shaped or
urn-shaped tube and 5-lobed spreading limb, falling off after,
flowering. Petals 5. Stamens 3-5 times as numerous, or
indefinite, inserted on the throat of the calyx-tube. Pistil 1,
long-styled, with 2 ovules, ripening into a single stone-fruit.

A. Stone oval, compressed; fruit smooth when ripe. Branches often
spiny. (Plums.)

1. P. americana, Marsh. WILD PLUM. A small tree, bark
thick and rough, branches spiny. Leaves ovate or obovate, acumi-
nate at the apex, rounded or cordate at the base, sharply serrate,
rather thick, downy beneath ; petioles glandular. Flowers in lat-
eral, sessile umbels, appearing with or before the leaves; pedicels
£-£ in. long, flowers £— f in. in diameter. Calyx downy within;
fruit globose, red or yellow, ^-1 in. in diameter. Common in
woods.*

2. P. angustifolia, Michx. CHICKASAW PLUM. A small tree
with spiny branches. Leaves lanceolate or oblong-lanceolate, acute
at the apex, usually obtuse at the base, finely and sharply serrate,
rather thin, smooth. Flowers in lateral, sessile umbels, pedicels
short. Calyx smooth. Fruit yellowish-red, subglobose, skin thin,
stone only slightly compressed. In old fields, S.*

B. Stone deeply furrowed and pitted; fruit downy when ripe.
Branches not spiny. (Peaches and almonds.')

3. P. persica, Sieb. and Zucc. PEACH. A tree with a rounded
top; bark nearly smooth. Leaves lanceolate, taper-pointed, finely
serrate, smooth on both sides ; petioles usually bearing 2 or 4
crescent-shaped or cup-shaped glands. Flowers pink, scaly-bra cted.
Fruit ovoid, with a seam along one side. Often escaped from culti-
vation.*

C. Stone more or less spherical ; fruit smooth when ripe. Branches
not spiny. (Cherries.)

DICOTYLEDONOUS PLANTS

117

4. P. virginiana, L. CHOKECHERRY. A shrub or small tree,
5-20 ft. high. Leaves thin, oval or obovate, pale, pointed, sharply
serrate. Flowers small, white, in short racemes. Fruit bright red,
turning at length to dark crimson, very puckery until fully ripe.
River banks and thickets.

5. P. serotina, Ehrh. WILD BLACK CHERRY. Often becoming a
large tree; bark on old trees rough, nearly black. Leaves rather
thick, oval to lanceolate-ovate, acute or taper-pointed at the apex,
finely serrate with calloused teeth, smooth above, downy on the veins
beneath. Racemes terminal, long and spreading. Flowers white.
Fruit globose, about \ in. in diameter, purplish-black. In rich
woods. Wood much used in cabinet-making.*

6. P. Cerasus, L. CHERRY. Often becoming a large tree.
Leaves oval or ovate, acute or taper-pointed at the apex, rounded at
the base, irregularly serrate-dentate, smooth on both sides, resinous
when young. Flowers in lateral umbels, white ; pedicels long and
slender. Fruit globose, red or black. This is the European species
from which most of our cultivated varieties have been developed.*

46. LEGUMINOS^. PULSE FAMILY.

Herbs, shrubs, or trees. Leaves alternate, usually com-
pound (either pinnately or palmately), with stipules, the leaf-
lets mostly entire. Calyx of 5 sepals, which are more or less
united, often somewhat irregular. Corolla, of 5 petals, often

FIG. 14. — I, Diagram of Flower of Sweet Pea, Lathyrus odoratus. II, Vertical
Section of Flower (magnified). Ill, Calyx (magnified).

Ill

FIG. 15. — I, Stamens and Pistil of Sweet Pea (magnified). II, Fruit.. Ill, Part of
Fruit, showing one seed.

118 FOUNDATIONS OF BOTANY

papilionaceous or somewhat regular, in No. XV much reduced.
Stamens diadelphous (Fig. 15), monadelphous, or distinct.
Ovary simple, free from the calyx. Fruit usually a 1-celled
pod (Fig. 15). Seeds one or several, without endosperm.

Flower regular, small. Stamens hypogynous. Leaves twice pinnate.

Petals not united to each other. Stamens 5 or 10. Pod
smooth. Desmanthus, I.

Corolla gamopetalous, 5-cleft. Stamens 8 or 10. Pod minutely
prickly or rough. Schrankia, II.

Trees. Flowers somewhat or not at all papilionaceous ; sometimes almost
regular. The upper petal inside the others in the bud. Stamens 10
or less, usually not united to each other, borne on the calyx.

Flowers imperfectly papilionaceous. Leaves simple.

Cercis, III.

Flowers not papilionaceous. Thornless. Gymnocladus, IV.

Flowers not papilionaceous. Thorny. Gleditschia, V.

Herbs or trees. Flowers decidedly papilionaceous. The upper petal
external in bud and enclosing the others. Stamens 10, not united to
each other.

Trees. Cladrastis, VI.

Herbs. Baptisia, VII.

Shrubs with a corolla of one petal only. Amorpha, XV.

Herbs, shrubs, or trees. Flowers decidedly papilionaceous. Stamens
monadelphous or diadelphous (in the latter case usually 9 and 1, a* in
Fig. 15).

DICOTYLEDONOUS PLANTS 119

1. Stamens with anthers of two forms. Leaves palmately com-

* pound.

Herbs. Leaves with many leaflets. Lupinus, VIII.

Trees. Laburnum, IX.

Low shrubs. Cytisus, X.

2. Anthers all alike except in No. 14.

Leaves usually with 3 leaflets. Leaflets with fine teeth,

except in No. 14.

(a) Pod coiled. Medicago, XI.

(&) Pod not coiled. Flowers in racemes. Melilotus, XII.

(d) Leaflets entire. Psoralea, XIY.

3. Leaves odd-pinnate, with more than 3 leaflets.

(e) Low woody shrubs. Amorpha, XV.
(/) Tall twining shrubs. Wistaria, XVI.
(g) Trees. Robinia, XVII.
(A) Herbs. Astragalus, XVIII.

4. Leaves pinnate, the midrib prolonged into a tendril.

(i) Leaflets usually many pairs. Style slender, bearded
only at the tip or all round the upper portion. Pod
2-several-seeded. Vicia, XIX.

(/) Leaflets few or several pairs. Style bearded along one
face only. Pod several-seeded. Lathyrus, XX.

(&) Leaflets 1-3 pairs. Style enlarged above, grooved on
the back. Pod several-seeded ; seeds large, globular
or nearly so. Pisum, XXI.

I. DESMANTHUS, Willd.

Shrubs or perennial herbs ; stems erect or diffuse, smooth.
Leaves abruptly twice-pinnate ; stipules small. Flowers in
heads or spikes, on axillary peduncles, the upper perfect, the
lower often staminate or neutral. Calyx 5-toothed. Corolla
of 5 distinct petals or 5-cleft. Stamens 5-10, distinct.
Ovary nearly sessile, flat, several-seeded.*

120 FOUNDATIONS OF BOTANY

1. D. brachylobus, Benth. DESMANTHUS. Stem erect or ascend-
ing, smooth, 1-4 ft. high. Pinnae 6-14 pairs, each with, a minute
gland at the base ; leaflets 20-30 pairs, small, linear. Heads glo-
bose. Stamens 5. Pods several, on a peduncle 2-3 in. long, curved,
flat, 2-valved, 3-6-seeded. Open, sandy fields.*

H. SCHRANKIA, Willd.

Perennial herbs ; stems reclining or prostrate, prickly, 2-5
ft. long. Leaves twice-pinnate ; stipules bristly. Flowers
perfect or somewhat monoecious, in axillary peduncled heads.
Calyx minute. Corolla tubular, 5-cleft. Stamens 8-10, dis-
tinct. Pod long, prickly, 1 -celled.*

1. S. uncinata, Willd. SENSITIVE BRIER, SENSITIVE ROSE,
SHAME VINE. Plant covered with hooked prickles. Leaflets ellip-
tical, with a conspicuous network of veins beneath ; leaves closing
gradually after being touched. Flowers rose-colored. Pods nearly
cylindrical, 2 in. long. Dry, sandy soil and rolling prairies, espe-
cially S. and W.

IH. CERCIS, L.

Trees. Leaves simple with stipules. Flowers in axillary
clusters, papilionaceous. Calyx bell-shaped, 5-toothed. Sta-
mens 10, distinct. Ovary short-stalked ; ovules several.
Fruit a flattened pod.

1. C. canadensis, L. REDBUD. A small tree, 10-20 ft. high, wood
hard but weak, bark smooth, dark-colored. Leaves broadly cordate,
abruptly acute, rather thick, very smooth above, often slightly
downy below. Flowers several in a cluster, appearing before the
leaves, pinkish-purple. Pod oblong, compressed, many-seeded. Com-
mon on rich soil, especially S.*

IV. GYMNOCLADUS, Lam.

A large, thornless tree, its twigs few and stout. Leaves
very large, twice pinnately compound, without stipules.
Flowers regular, whitish, dioecious or somewhat monoecious,
in racemes at the ends of the branches. Calyx-tube rather
long, its 5 lobes spreading. Petals oblong, all alike, inserted
with the stamens on the throat of the calyx. Stamens of
the fertile flowers usually not pollen-bearing. Pod hard, flat,

DICOTYLEDONOUS PLANTS 121

partly filled with a sweet substance, slow in opening. Seeds
several, flattish, over ^ in. in diameter, very hard and shining.

1. G. canadensis, Lam. KENTUCKY COFFEE TREE. Tree 50 ft.
or more in height, with rough gray bark. Leaves 2-3 ft. long, the
leaflets vertical. Pods sometimes nearly 1 ft. long. Rich soil and
river bottoms, especially S. and W.

V. GLEDITSCHIA, L.

Large trees ; bark dark-colored, nearly smooth. Leaves
usually pinnately twice compound ; leaflets serrate. Flowers
somewhat monoecious, in small spike-like racemes. Calyx
spreading, 3-5-cleft. Petals as many as the sepals and
inserted at the summit of the tube. Stamens 5-10, distinct,
inserted with the petals. Ovary nearly sessile, ovoid or
elongated. Fruit a 1 or many seeded, leathery pod.*

1. G. Triacanthos, L. HONEY LOCUST. A large tree, usually armed
with stout, branched thorns, which are sometimes a foot or more in
length. Leaves petioled ; leaflets short-stalked, lanceolate-oblong,
base inequilateral, smooth above, often downy below. Racemes soli-
tary or in small clusters, drooping. Flowers inconspicuous, greenish.
Pod linear-oblong, often 12-15 in. long by 1 in. wide, twisted, many-
seeded, smooth and shiny, pulpy within. In. rich woods. [The
thorns are plainly modified branches bearing dormant buds, and
often partially developed leaves. The early spring leaves are usually
only once compound, while those of later growth are almost invaria-
bly twice compound. Often a single leaf will show both forms of
compounding.]*

VI. CLADRASTIS, Raf.

A moderate-sized tree with smooth dark gray bark and
yellow wood. Leaves of 7-11 smooth oval or ovate leaflets.
Flowers creamy-white, in long, drooping panicles. Calyx
5-toothed. Standard large, nearly round, reflexed ; petals of
the keel and wings separate and straight. Stamens 10,
unconnected with each other. Pod borne on a short stalk
above the calyx. Seeds 4-6.

1. C. tinctoria, Raf. YELLOW WOOD. Tree 50 ft. or less in
height, much branched, with a round, spreading top. Hillsides, in
fertile soil, south central states. Also considerably planted as a
shade tree.

122 FOUNDATIONS OF BOTANY

VII. BAPTISIA, Vent.

Perennial herbs; stems erect, widely branched. Leaves
simple or palmate, of 3 leaflets. Flowers in racemes. Calyx
4-5-lobed, persistent, the upper lobe usually longer and
notched ; standard rounded, its sides reflexed, wings about
as long as the keel. Stamens 10, distinct. Pod stalked,
long-pointed by the remains of the style. Plants usually
becoming black in drying.*

1. B. tinctoria, R. Br. WILD INDIGO. Stem smooth, slender,
2-4 ft. high; branches slender. Leaves of 3 leaflets, on short
petioles, the upper nearly sessile ; stipules minute, quickly deciduous.
Leaflets obovate to oblauceolate, obtuse at the apex, wedge-shaped
at the base, entire. Racemes numerous, terminal. Flowers yellow,
£ in. long. Pod globose, ovoid, on a stalk about the length of the
calyx, point long and slender. Plant blackening in drying. Com-
mon on dry, sandy soil.*

2. B. leucophaea, Nutt. Low, hairy, and branching. Leaves
nearly sessile, leaflets oblanceolate or obovate-spatulate. Stipules tri-
angular-ovate, large, persistent ; bracts large and leaf-like. Racemes
long. Flowers large, yellowish-white. Pod ovoid, swollen. Prairies
and open woods, W. and S. .

3. B. leucantha, Torr. and Gr. Stout, smooth, and covered with
a bloom, 3 ft. or more high, with spreading branches. Petioles
short ; lanceolate stipules and bracts falling off early. Racemes
erect. Flowers large, white. Pods ellipsoidal, 2 in. long, borne on
a stalk twice as long as the calyx. Rich river bottoms and prairies.

4. B. alba, R. Br. WHITE WILD INDIGO. Stem smooth and
with a bloom, often purple, 2-3 ft. high ; branches slender, spreading.
Leaves petioled, with 3 leaflets; stipules minute, soon deciduous.
Flowers white, mostly in a single raceme which is 1-3 ft. long, with
occasionally lateral, few-flowered racemes. Pod linear-oblong, the
point very slender and soon deciduous. Plant unchanged in drying.
In damp soil.*

5. B. australis, R. Br. BLUE FALSE INDIGO. Stem smooth,
stout, 2-4 ft. high. Leaves of 3 leaflets, short-petioled ; stipules
lanceolate, persistent, longer than the petioles ; leaflets oblong,
wedge-shaped or narrowly obovate, entire. Flowers bright blue,
1 in. long, in terminal, erect, loosely flowered racemes ; stalk about
the length of the calyx. Pod oblong, with a slender, persistent
point. Banks of rivers ; often cultivated for ornament.*

DICOTYLEDONOUS PLANTS 123

Vin. LUPINUS, Tourn.

Biennial or perennial herbs. Leaves simple or palmately
compound. Flowers showy, in terminal racemes. Calyx
2-lipped, 5-toothed. Standard round, with the sides reflexed,
keel scythe-shaped. Stamens monadelphous, anthers alter-
nately oblong and roundish. Ovary sessile ; matured pod
oblong, several-seeded, often compressed between the seeds.1*

1. L. perennis, L. Perennial ; stem erect, downy, 12-18 in. high.
Leaves palmately 7-9 foliate ; leaflets obovate or oblanceolate, obtuse
and mucronate at the apex, slightly downy ; petiole slender ; stipules
small. Racemes terminal, slender, loosely many-flowered. Flowers
purple, blue, pink, or white. Pod oblong, densely downy, few-seeded.
Dry, sandy soil.*

IX. LABURNUM, Benth.

Trees or shrubs. Leaves of 3 leaflets, with very small
stipules or none. Flowers golden-yellow, in slender, drooping
racemes. Calyx 2-lipped, the upper lip 2-toothed, the lower
3-toothed. Standard ovate, upright, of the same length as
the straight wings. Stamens diadelphous (9 and 1). Ovary
and pod somewhat stalked above the calyx, several-seeded.

1. L. vulgare, Gris. LABURNUM, GOLDEN CHAIN. A small tree,
with smooth, greenish bark. Leaves with slender petioles ; leaflets
oblong-ovate, acute at the base, taper-pointed, downy beneath.
Flowers showy, in graceful racemes. Cultivated from Europe.

X. CYTISUS, L.

Shrubs, rarely spiny. Leaves of 1-3 leaflets or none ; stip-
ules very small. Calyx 2-lipped, the upper lip slightly
2-toothed, the lower 3-toothed. Keel straight or a little
curved, blunt, turned down after flowering. Stamens with
their filaments all united ; anthers every other one short and
attached by its center, the alternate ones long and fastened
by their bases. Style curved in, or, after the flower opens,
coiled up. Pod flat, long, many-seeded.

1. C. canariensis, Steud. A shrub with many rather stiff, erect,
slender branches. Leaves abundant, very small, covered with soft

124 FOUNDATIONS OF BOTANY

gray hairs ; leaflets 3, obovate. Flowers rather small, yellow, in
somewhat erect racemes. Cultivated in greenhouses. From the
Canary Islands.

XI. MEDICAGO, Tourn.

Annual or perennial herbs ; leaves petioled, of 3 toothed
leaflets. Flowers in terminal and axillary spikes or racemes.
Calyx 5-toothed, the teeth, short and slender. Standard
oblong, much longer than the wings or keel. Stamens 10,
diadelphous. Ovary sessile. Pod 1-several-seeded, coiled,
not splitting open, often spiny.*

1. M. sativa, L. ALFALFA. Perennial; stems erect, branching,
downy when young, becoming smooth with age, 2-3 ft. high.
Leaves short-petioled ; leaflets obovate, sharply dentate towards the
apex, obtuse or sometimes notched or mucronate ; stipules lanceolate,
entire. Flowers blue, small, in rather close spikes ; pods downy,
coiled, few-seeded. Introduced from Europe, and cultivated for hay
and pasture.*

2. M. lupulina, L. BLACK MEDICK, NONESUCH. An annual or
biennial, much branched, reclining herb, with stems from 6-20 in.
long. Leaves very short-petioled; leaflets obovate, acute, ^-f in.
long, toothed near the tip. Flowers small, yellow, in short spikes.
Pods very small, 1-seeded, kidney-shaped, black. Roadsides and
waste ground, introduced from Europe.

XH. MELILOTUS, Tourn.

Annual or biennial herbs. Leaves petioled, of 3 leaflets.
Flowers small, white or yellow, in c se axillary and terminal
racemes. Calyx 5-toothed, the teetn nearly equal. Standard
erect, wings and keel cohering. Stamens 10, diadelphous.
Pod longer than the calyx, 1-4-seeded.*

1. M. alba, Lam. MELILOTUS. Biennial; stem erect, branching,
smooth or the young branches slightly downy. Leaflets oblong or
oblanceolate, rounded or truncate at the apex, serrate ; stipules small.
Racemes long, slender, erect. Flowers white. Standard longer than
the wings and keel. Pod ovoid, wrinkled, drooping, mostly 1-seeded,
scarcely opening. Common as a weed and widely cultivated.*

2. M. officinalis, Willd. YELLOW SWEET CLOVER. A stout,
upright, branching herb, 2-4 ft. high, looking much like the preced-
ing species, but coarser. Flowers yellow. Waste ground and road-
sides. Introduced from Europe.

DICOTYLEDONOUS PLANTS 125

XIII. TRIFOLIUM, Tourn.

Annual, biennial, or perennial herbs. Stems more or less
spreading. Leaves petioled, of 3 toothed or serrate leaflets ;
stipules adnate to the petioles. Flowers white, yellow, or
red, in heads. Calyx 5-cleft, the teeth nearly equal and
subulate. Petals withering-persistent, keel shorter than the
wings. Stamens diadelphous. Pod smooth, 1-6-seeded,
scarcely opening.*

1. T. procumbens, L. Low HOP-CLOVER. Annual ; stem slender,
erect, or spreading, downy, 6-10 in. long. Leaves short-petioled ;
leaflets obovate or obcordate, finely dentate, the middle one distinctly
stalked ; stipules lanceovate. Flowers yellow, reflexed in fruit. Pod
1-seeded. Common on clay soil, in waste places.*

2. T. incarnatum, L. CRIMSON CLOVER. Annual ; stem erect,
somewhat branched, downy, 1-2 ft. high. Lower leaves long-, the
upper short-petioled; leaflets obovate or wedge-shaped, toothed at
the apex. Flowers bright crimson, sessile, in terminal heads which
finally become much elongated. Calyx silky, its lobes long and
plumose. Introduced and cultivated for fodder.

3. T. pratense, L. RED CLOVER. Biennial or short-lived peren-
nial ; stems spreading, branching, downy, 1-3 ft. long. Leaves long-
petioled ; stipules large ; leaflets oval to obovate, finely toothed, often
with a dark triangular spot near the center. Flowers red or purple,
in globose heads, erect in fruit. Calyx-teeth bristle-shaped, hairy.
Pod 1-3 seeded. Introduced and widely cultivated.*

4. T. carolinianum, Michx. CAROLINA CLOVER. Perennial;
stems spreading or ascending, much-branched, downy, 6-10 in. long.
Leaves short-petioled ; leaflets small, obovate or obcordate, slightly
toothed. Heads small, globose, on long peduncles. Flowers white,
tinged with purple, reflexed in fruit. Pod 4-seeded. Common in
waste places S.*

5. T. repens, L. WHITE CLOVER. Perennial; stems widely
branching at the base, prostrate and creeping, nearly smooth, 6-12
in. long. Leaves long-petioled ; leaflets oval, obovate or obcordate,
minutely toothed. Heads globose, long-peduncled. Flowers white,
reflexed in fruit. Pod 3-4-seeded. Introduced; common about
houses and in pastures.*

6. T. hybridum, L. ALSIKE CLOVER. Perennial, considerably
resembling No. 5, but the stems more upright and stouter. Leaflets
varying from broadly ovate to ovate-lanceolate, mucronate or
slightly notched, the margins fringed with hairs ; stipules prolonged
into bristle-like points. Flowers rose-color and white, very fragrant.
In fields and along roadsides. Introduced from Europe.

126 FOUNDATIONS OF BOTANY

XIV. PSORALEA, L.

Perennial herbs ; whole plant glandular-dotted. Leaves of
3-5 leaflets ; stipules cohering with the petioles. Flowers in
axillary or terminal spikes or racemes. Calyx 5-cleft, the
lobes nearly equal. Standard ovate or orbicular, keel
incurved, obtuse. Stamens monadelphous or diadelphous,
5 of the anthers often undeveloped. Ovary nearly sessile.
Pod included in the calyx, often wrinkled, remaining closed,
1-seeded.*

1. P. melilotoides, Michx. SAMSON'S SNAKEROOT. Stem erect,
slender, branching above, downy, 1-2 ft. high. Leaves of 3 leaflets ;
petioles shorter than the leaflets ; stipules awl-shaped ; leaflets
elliptical or oblong-lanceolate, sparingly glandular-dotted, the termi-
nal one stalked. Loosely flowered spikes axillary and terminal, on
peduncles much longer than the leaves. Flowers blue or purple,
about £ in. long. Pod compressed-globose, wrinkled transversely.
Dry soil.*

2. P. tenuiflora, Pursh. Upright, slender, bushy and branching,
2-4 ft. high, covered wheu young with a fine grayish down. Leaves
palmately compound, with 3-5 linear to obovate-oblong leaflets, cov-
ered with glandular dots. Flowers i-£ in. long, loosely racemed.
Pod rough with glands. Prairies, W.

3. P. esculenta, Pursh. POMME BLANCHE, TIPSIN, DAKOTA TUR-
NIP. Clothed with roughish hairs. Stem 5-15 in. high, erect and
stout. Root turnip-shaped, starchy, eatable. Leaves palmately
compound, with 5 lance-oblong leaflets. Flowers £ in. long, in a
dense ellipsoidal spike. Pod hairy, with a pointed tip. High
prairies or plains, especially N. W.

XV. AMORPHA, L.

Small shrubs, glandular-dotted. Leaves odd-pinnate. Flowers
purple, blue, or white, in slender spikes or racemes. Calyx
5-toothed, persistent. Standard obovate, concave, wings and
keel none. Stamens monadelphous, projecting much. Ovary
sessile. Pod curved, glandular-roughened, 1-2-seeded, never
opening.*

1. A. fruticosa, L. FALSE INDIGO. A shrub 6-15 ft. high, with
smooth, dark-brown bark. Leaves petioled ; leaflets 15-21, short-
stalked, oblong, obtuse or notched, sparingly punctate with clear
dots. Slender flowering spikes, panicled or solitary, 4-6 in. long.

DICOTYLEDONOUS PLANTS 127

Flowers blue or purple. Calyx-teeth short, nearly equal, downy.
Pod glandular. River banks.*

XVI. WISTARIA, Nutt.

Tall, twining shrubs. Leaves odd-pinnate. Racemes ter-
minal. Flowers large and showy. Calyx 2-lipped, the upper
lip 2-cleft, short, the lower longer and 3-cleft. Standard
large, round, with 2 calloused ridges at the base, wings
eared at the base, keel scythe-shaped. Pod long, stalked,
leathery, 2-valved, several-seeded.*

1. W. frutescens, Poir. WISTARIA. Stem climbing 30-40 ft.,
often 2-3 in. in diameter at the base ; branches and leaves downy
when young, becoming smoother with age. Leaves short-petioled ;
stipules minute ; leaflets 9—17, ovate-lanceolate, acute at the apex,
rounded at the base. Racemes large, densely flowered. Calyx
downy. Corolla lilac-purple, one wing with a short and one with a
long appendage at the base. Pod 2-3 in. long, 2-4-seeded. River
banks S. Often cultivated for ornament.*

2. W. chinensis, DC. CHINESE WISTARIA. Larger and faster
growing than No. 1. Racemes longer and more slender. Wing-
appendages equal. Seldom fruiting in this region. Cultivated from
China or Japan.

XVII. ROBINIA, L.

Trees or shrubs. Leaves odd-pinnate ; stipules often spiny.
Flowers showy, in axillary racemes. Calyx short, 5-toothed,
the two upper teeth shorter and partially united. Standard
large, orbicular, reflexed, keel obtuse. Stamens diadelphous.
Style bearded on one side. Pod compressed, several-seeded.*

1. R. Pseudacacia, L. BLACK LOCUST. A tree of medium size;
bark rough and nearly black; twigs and leaves smooth. Leaflets
9-15, ovate or oblong, obtuse and slightly mucronate at the apex;
stipules forming persistent spines. Racemes loose, pendulous, 3-5 in.
long. Flowers white, fragrant. Pod smooth, 4-8-seeded. Intro-
duced and quite common ; w^ood very durable when exposed to the
weather, and extensively used for posts.*

XVIII. ASTRAGALUS, Tourn.

Mostly perennial herbs. Leaves odd-pinnate. Flowers in
spikes or racemes. Calyx 5-toothed. Petals long, erect, with

128 FOUNDATIONS OF BOTANY

claws. Standard narrow. Stamens diadelphous (9 and 1).
Pod usually swollen, sometimes fleshy and eatable, several-
many-seeded.

1. A. caryocarpus, Ker. GROUND PLUM, BUFFALO APPLE. Covered
with pale, close-lying down. Leaflets narrow, oblong. Flowers violet-
purple, in a short, narrow raceme. Fruit looking like a small, green,
pointed plum, about f in. in diameter, eatable. N". W., and S. to
Texas.

2. A. mexicanus, A. DC. PRAIRIE APPLE. Smooth or with
some loose hairs. Corolla cream-color, with the tip bluish. Fruit
globular, not pointed, eatable. Prairies, Illinois and S. W.

3. A. canadensis, L. Erect, often tall (1-4 ft. high), more or less
downy. Leaflets oblong, 21-27. Flowers pale greenish, in long
spikes. Pod dry, 2-celled, sessile. River bottoms, prairies, and woods.

XIX. VICIA, Tourn.

Climbing or spreading herbs. Leaves odd-pinnate, usually
ending in a tendril. Leaflets many, entire or toothed at the
tip ; stipules half arrow-shaped. Flowers blue, purple, or yel-
low, in axillary racemes. Calyx-teeth nearly equal. Wings
adnate to the keel. Stamens diadelphous (9 and 1) ; fila-
ments thread-shaped, anthers all alike. Style bent, smooth or
downy all round or bearded below the stigma ; ovules usually
many. Pod flattened, 2-several-seeded. Seeds globular.

1. V. americana, Muhl. WILD VETCH, BUFFALO PEA. Peren-
nial. Smooth, 1-3 ft. high. Leaflets 10-14, elliptical or ovate-
oblong, obtuse. Peduncles shorter than the leaves, 4-8-flowered.
Flowers bluish-purple, f in. long. Common N. and W.

2. V. caroliniana, Walt. Perennial. Smooth or nearly so, 4-6 ft.
high. Leaflets 8-24, narrowly oblong, blunt. Peduncles loosely
flowered. Flowers smaller than in No. 1, whitish or tipped with pale
purple. River banks.

3. V. sativa, L. COMMON VETCH. Annual. Stem simple,
smooth or downy, reclining, 1-3 ft. long. Leaves short-petioled ;
leaflets 5-7 pairs, obovate-oblong to linear, obtuse, notched and
mucronate at the apex. Flowers in pairs, nearly sessile in the axils,
pale purple, £-1 in. long. Pod linear, several-seedecf. Introduced
from Europe and common in cultivation.*

DICOTYLEDONOUS PLANTS 129

XX. LATHYRUS, Tourn.

Like Vicia excepting that the leaflets are fewer and the
style is bearded on the side toward the standard.

1. L. venosus, Muhl. VEINY VETCH. Perennial. Stem stout,
prominently angled, climbing or reclining, 2-5 ft. long. Leaves
short-petioled ; stipules large, lanceolate ; leaflets 5-7 pairs, broadly
ovate-obtuse, mucronate. Peduncles nearly as long as the leaves,
many-flowered. Flowers purple, ^ in. long. Calyx-teeth very
unequal. Pod linear, veined, 4-6-seeded. Shady banks and moist
prairies.*

2. L. maritimus, Bigelow. BEACH PEA. Perennial. Stem stout,
1-2 ft. high. Stipules broadly ovate and heart or halberd shaped,
nearly as large as the 6-12 leaflets, of which the lower pair is the
largest ; tendrils pretty large. Flowers large, blue or purple. Sea-
shores and beaches of the Great Lakes.

3. L. palustris, L. WILD PEA. Stem frequently winged, slender,
and climbing by delicate tendrils at the ends of the leaves. Stipules
narrow and pointed ; leaflets 4-8, narrowly oblong to linear, acute.
Peduncles bearing 2-6 pretty large, drooping, blue, purple, and
white flowers. Damp thickets and borders of swamps.

4. L. odoratus, L. SWEET PEA. Annual. Stem roughish-
hairy, it and the petioles winged. Leaflets only one pair, oval or ob-
long. Flowers large, 2 or 3 on the long peduncles, sweet-scented,
white, rose-color, purple, or variegated. Cultivated from Europe.

XXI. PISUM, L.

Climbing or prostrate herbs. Style enlarged above, grooved
on the back, soft-hairy down on the inner edge. Leaflets
1-3 pairs. Mowers and fruit much like those of Lathyrus.

1. P. sativum, L. COMMON PEA. Annual. Smooth and covered
with a bloom. Leaflets usually 2 pairs ; tendrils branching ; stip-
ules large, ovate, rather heart-shaped at the base. Peduncle several-
flowered. Flowers white, bluish, reddish, or variegated. Pods large ;
seeds globular or somewhat flattened and wrinkled. There are
many varieties, differing greatly in size, of the plant and of the
fruit. Cultivated from Europe (?).

47. GERANIACE^. GERANIUM FAMILY.

Herbs or small shrubs. Leaves simple, usually with glan-
dular hairs which secrete an aromatic oil. Flowers perfect,

130 FOUNDATIONS OF BOTANY

axillary and solitary or clustered, regular or slightly irregular
hypogynous, tj^eir parts in fives. Stamens 5 or 10, monadel-
phous at the ba^e. Carpels 5, each 2-ovuled, splitting away
with their long stj^es when ripe from a central axis and thus
scattering the seeds.

I. GERANIUM, Tourn.

Herbs, rarely shrubs. Leaves with stipules, opposite or
alternate, usually cut or lobed. Flowers regular, on 1-2-
flowered axillary peduncles. Sepals and petals 5. Stamens
10, ripening in 2 sets. Ovary 5-lobed, 5-beaked ; stigmas 5.

1. G. maculatum, L. WILD CRANESBILL, WILD GERANIUM.
Perennial, with an erect, hairy stem, 12—18 in. high. Leaves about
5-parted, marked with pale blotches, the root-leaves long-petioled.
Flowers large (1 in. or more in diameter), light purple, somewhat
corymbed. Petals entire, twice as long as the calyx, the claw
bearded. Open woods and thickets ; common.

2. G. robertianum. HERB ROBERT. Annual or biennial. Stems
somewhat hairy, weak and spreading, reddish. Leaves of 5 leaflets,
the latter once or twice pinnately cut, long-petiolecL Flowers light
purple, about ^ in. in diameter, streaked with dark and light red.
Claws of petals smooth. Damp woods and ravines E.

H. PELARGONIUM, L'Her.

Perennial herbs or shrubs. Leaves with stipules, scented.
Flowers much as in the preceding genus, but one of the
sepals hollowed out below into a nectar-bearing tube extend-
ing down the pedicel. The 2 upper petals different in size or
shape from the other 3. Cultivated from the Cape of Good
Hope. [Most of the species are commonly, though not quite
correctly, called " geraniums." Only a few of the commonest
are here described.]

1. P. peltatum, Ait. IVY GERANIUM. Stems somewhat prostrate
and trailing. Leaves somewhat peltate, smooth or nearly so.
Flowers pink or white.

2. P. zonale, Willd. HORSESHOE GERANIUM. Stem erect,
widely branched, woody below. Leaves alternate, opposite or some-
times in 3's, round or kidney-shaped, palmately veined, crenate,

DICOTYLEDONOUS PLANTS 131

downy, usually with a dark zone near the middle. Flowers in a
long peduncled umbel, showy, red or white, often double. Number-
less varieties in cultivation.

3. P. graveolens, Ait. ROSE GERANIUM. Stem erect or ascend-
ing, densely downy, 1-3 ft. high. Leaves alternate, palmately lobed
or divided, the lobes often finely dissected, rolled under at the edges.
Flowers umbelled, small, light purple with darker veins ; whole
plant very fragrant. Common in cultivation.

4. P. odoratissimum, Ait. NUTMEG GERANIUM. Branches
crooked and straggling from a very short, moderately stout main
stem. Leaves small, roundish and scalloped, covered with velvety
down, very fragrant. Flowers white, inconspicuous, on short pedi-
cels, the petals hardly longer than the calyx.

48. OXALIDACE^. WOOD-SORREL FAMILY.

Herbs or woody plants. Leaves compound. Flowers in
fives, perfect, regular, hypogynous. Stamens 10, somewhat
monadelphous at the base. Ovary with several ovules in
each cell. Fruit a capsule.

OXALIS, L.

Acid herbs. Leaves radical or alternate, with or without
stipules, usually of 3 leaflets, which droop at night. Sepals
5. Petals 5. Stamens 10. Ovary 5-lobed, 5-celled ; styles 5.

1. 0. Acetosella, L. WOOD-SORREL. Stemless, from a creeping,
scaly rootstock. Leaves all radical, long-petioled, of 3 inversely
heart-shaped leaflets ; scape slender, 2-5 in. high, 1-flowered. Flowers
nearly 1 in. in diameter, white, veined with red or purple. Cold
woods N.

2. 0. violacea, L. VIOLET WOOD-SORREL. Perennial from a
bulbous root, stemless. Leaves long-petioled; leaflets inversely
heart-shaped, sometimes slightly downy, often with a dark zone
near the middle. Scapes usually longer than the petioles, umbel-
lately 4-10-flowered ; pedicels slender. Flowers violet-purple, nod-
ding. Petals obtuse, 2-3 times as long as the sepals ; scapes and
petioles 4-5 in. long. Common in rich woods.*

[The forms with small yellow flowers, hitherto referred to O. cor-
niculata, belong to several nearly related species too difficult for the
beginner.]

132 FOUNDATIONS OF BOTANY

49. TROP-^OLACE^). INDIAN CRESS FAMILY.

Smooth and tender herbaceous plants, with biting juice, often
climbing by the petioles of their simple leaves. Leaves alter-
nate, without stipules. Peduncles axillary, 1-fLowered. Sepals
3-5, the upper one with a long, distinct spur. Petals 1-5,
hypogynous, not always all alike. Stamens 6-10, perigynous,
distinct. Ovary 1, 3-cornered, made up of 3-5 1-ovuled
carpels; style 1 ; stigmas 3-5. Fruit not opening.

TROPJEOLUM, L.

Characteristics of the genus those of the family above
given, together with the following :

Petals usually 5, clawed, the 2 upper inserted at the mouth
of the spur and unlike the 3 lower ones. Stamens 8, ripen-
ing unequally, the filaments curved. Fruit 3-celled, 3-seeded.
Cultivated from S. A. for the very showy flowers and the
sharp-flavored fruits, which are often pickled.

1. T. majus, L. COMMON NASTURTIUM. Climbing by the petioles
6-8 ft. (there is also a low variety which does not climb). Leaves
roundish but more or less 6-angled, peltate, with the petiole attached
near the middle. Flowers varying from almost white to nearly black,
but commonly crimson, scarlet, or flame-color.

50. LINACEJE. FLAX FAMILY.

. Herbs, shrubs, or trees. Leaves usually alternate, simple,
entire, sometimes with stipules. Flowers variously clus-
tered. Sepals 5, distinct or coherent. Petals 5, hypogynous.
Stamens 5, monadelphous below. Pod 8-10-seeded, with
twice as many cells as there are styles.

LINUM, Tourn.

Herbs or small shrubs, with tough, fibrous bark. Leaves
sessile. Flowers in corymbs or panicles. Sepals 5, entire.
Petals 5, distinct or coherent below, falling in a few hours
after expanding.

DICOTYLEDONOUS PLANTS 133

1. L. virginianum, L. WILD FLAX. Stem rather slender, erect
and cylindrical ; branches cylindrical. Leaves small, varying from
oblong to lanceolate or spatulate, the lower often opposite. Flowers
small, yellow. Capsules flattened at right angles to the pedicels.
Dry woods and pastures.

2. L. usitatissimum, L. COMMON FLAX. Stem erect, with
corymbed branches at the top. Leaves narrowly lanceolate. Flowers
handsome, large, blue. Cultivated for the fiber. From Europe ;
introduced here to some extent.

51. RUTACE-ffi. RUE FAMILY.

Shrubs or trees. Leaves alternate, compound, without
stipules, marked with translucent dots. Flowers perfect or
variously imperfect. Sepals and petals 3-5 or none ; petals
hypogynous or perigynous when present. Stamens as many
or twice as many as the sepals, inserted on the glandular disk.
Pistils 2-5, often partially united. Fruit a capsule, a key-
fruit, or in the important genus Citrus (orange, lemon, lime,
etc., not here described) a leathery-skinned berry, the outer
part of the skin containing many spherical oil-cavities.*

I. XANTHOXYLUM, L.

Trees or shrubs ; bark, twigs, and petioles usually prickly ;
leaves odd-pinnate, marked with translucent dots. Flowers
in axillary or terminal cymes or umbels, monoecious or
dioecious. Sepals and petals 3-5 or none. Stamens 3-5,
hypogynous. Pistils 2-5, distinct. Carpels 2-valved, 1-2-
seeded. Seeds smooth and shining.*

1. X. americanum, Mill. NORTHERN PRICKLY ASH, TOOTHACHE-
TREE. A prickly shrub, 8-12 ft. high, with aromatic bark. Leaves
pinnately compound; leaflets ovate-oblong. Flowers small and
greenish, in axillary umbels, appearing before the leaves. Petals
4-5. Pistils 3-5, the styles slender. Pods rather globose, somewhat
more than i in. in diameter, roughish, borne on a short stalk above
the receptacle, with a strong scent of lemon and tasting at first
aromatic, then burning. Rocky woods, ravines, and river banks.

134 FOUNDATIONS OF BOTANY

H. PTELEA.

Shrubs with smooth and bitter bark. Leaves with 3 leaflets.
Flowers in terminal cymes, somewhat monoecious. Sepals
3-6, deciduous, much shorter than the petals. Stamens 4-5,
longer than the petals and alternate with them. Pistillate
flowers producing imperfect stamens. Ovary compressed.
2-celled. Fruit a 2-celled, 2-seeded, broadly winged key.*

1. P. trifoliata, L. HOP-TREE, WAFER ASH. A shrub 4-8 ft.
high. Leaves long-petioled ; leaflets oval or ovate, acute, obscurely
serrate, the lateral ones oblique. Cymes compound. Flowers
greenish. Stamens mostly 4, filaments bearded, key about 1 in. in
diameter ; wing notched, strongly netted-veined. Rocky banks ; often
cultivated.*

52. POLYGALACEJE. POLYGALA FAMILY.

Herbs or shrubs. Leaves alternate or nearly opposite,
without stipules, simple. Flowers irregular. Sepals unequal,
the 2 inner wing-shaped and petal-like. Petals 3-5, hypogy-
nous, the 2 lateral ones often united with the hooded lower
one into a tube, split open at the base behind. Stamens 8,
filaments united into a split sheath, which is usually adnate
to the petals ; anthers usually opening by pores. Ovary
2-celled, 2-ovuled. [A difficult family for the beginner.]

POLYGALA, Tourn.

Herbs or shrubs. Flowers racemed or spiked, some of them
often cleistogamous. Petals adnate below to the stamen-
sheath. Anthers opening by transverse pores.

1. P. paucifolia, Willd. FRINGED POLYGALA, BABIES' TOES,
MAY WINGS. A low perennial herb, with branches 3-4 in. high
from a slender, creeping rootstock. Lower leaves scattered, small
and scale-like, the upper ones with petioles, crowded near the tips of
the branches, ovate or nearly so. Flowers of two kinds, the cleis-
togamous whitish, fertile, borne underground along the rootstock, the
terminal flowers large and showy (nearly an inch long), rose-purple,
with a beautiful fringed crest. Woods, especially N. and E.

DICOTYLEDONOUS PLANTS

135

2. P. Senega, L. SENECA SNAKEROOT. A perennial herb, with
several erect stems arising from stout, hard, knotty rootstocks.
Leaves lanceolate, oblong or lance-ovate, sessile. Flowers all alike,
small, white, in solitary close spikes. Rocky woods.

53. EUPHORBIACEJE. SPURGE FAMILY.

Herbs, shrubs, or trees, usually with a milky, more or less
acrid and sometimes poisonous juice. Flowers mostly apeta-
lous, monoecious or dioecious (Fig. 16). Ovary usually 3-celled,
with 1 or 2 ovules in each cell ; stigmas as many as the

FIG. 16. — Euphorbia corollata.

A, flower-cluster with involucre, the whole appearing like a single flower ; £, a
single staminate flower ; C, immature fertile flower, as seen after the removal of
the sterile flowers ; i, involucre ; s, stigmas.

cells or twice as many. Fruit a 3-lobed capsule. Seeds con-
taining fleshy or oily endosperm (Part I, Fig. 2). Most of
the family are natives of hot regions, many of them of pecu-
liar aspect from their adaptation to life in dry climates.
[The family is too difficult for the beginner in botany to
determine many of its genera and species with certainty, but
a few are described below.]

136 FOUNDATIONS OF BOTANY

I. EUPHORBIA, L.

Herbs or shrubs, with milky juice, often poisonous.
Flowers monoecious, enclosed in a 4-5-lobed involucre, which
is often showy and resembles a calyx or corolla, usually bear-
ing large glands at its notches. Sterile flowers many, borne
inside the involucre at its base (Fig. 16, A), each consisting only
of a single stamen attached by a joint to a pedicel which
looks like a filament. Fertile flower standing alone at the
center of the involucre (Fig. 16, (7) (soon pushed out by the
growth of its pedicel), consisting only of a 3-lobed and
3-celled ovary, 3 2-cleft styles, and 6 stigmas. Pod 3-celled
and 3-seeded.

A. Cultivated shrubs.

1. E. splendens, Bojer. CROWN OF THORNS. An extremely
prickly shrub, with many erect, few-leaved branches. Leaves
obovate or obovate-spatulate, mucronate, entire, each with two very
sharp prickles (longer than the petiole) as stipules. Peduncles long,
sticky, each bearing 2-4 objects, which appear to be showy scarlet
flowers, but which are actually 2-bracted involucres containing the
true flowers. Involucral scales somewhat kidney-shaped, mucronate.
Flowering all the year round. Cultivated in greenhouses. From
Mauritius.

B. Herbs with rather showy white flower-clusters.

2. E. corollata, L. FLOWERING SPURGE. Perennial. Stem
erect, umbellately branched above, smooth or downy, 1-3 ft. high.
Leaves of the stem alternate, those of the branches usually opposite
or whorled, rather thick, oval to narrowly oblong, pale beneath,
usually slightly downy. Flowering branches repeatedly forked ;
involucres terminal and in the forks of the branches, peduncled;
glands 4-5, oblong, green ; appendages white and petal-like, showy.
Capsule erect, seed smooth or faintly pitted. Common in dry, open
woods.

C. Herbs: No. 3 a native species, No. 4 cultivated from Europe or
escaping from gardens. Flower-clusters in umbels not white. Involucre
4 or 5 lobed, each lobe with a gland.

3. E. dictyosperma, Fischer and Mayer. Annual. Stem slender,
8-18 in. high, erect. Stem-leaves oblong-spatulate to obovate, ser-
rate ; floral ones roundish-ovate, somewhat heart-shaped. Flower-
cluster a compound umbel, the rays once or twice 3-forked, then
2-forked. Seeds covered with a network. Prairies and roadsides.

DICOTYLEDONOUS PLANTS 137

4. E. Cyparissias, L. CYPRESS SPURGE, CYPRESS, GRAVEYARD

Moss. A perennial, in dense clusters 6-12 in. high from running
rootstocks. Leaves much crowded, all sessile, the stem-leaves linear,
floral ones broadly heart-shaped. Flower-cluster a simple, many-
rayed umbel. Glands crescent-shaped. Cemeteries, roadsides, etc.,
escaped from cultivation; also cultivated in old gardens. From
Europe.

II. JATROPHA, L.

Shrubs or herbs. Leaves alternate. Flowers monoecious,
staminate and pistillate intermixed in the cymes, apetalous.
Calyx large, white, 5-lobed, corolla-like. Stamens numerous,
usually monadelphous. Ovary usually 3-celled, 3-seeded ;
styles 3, united at the base, several-parted.1*

1. J. stimulosa, Michx. SPURGE NETTL^. Perennial herbs armed
with stinging hairs ; stems erect, branched, bright green with white
lines, 8-15 in. high. Leaves long-petioled, deeply palmately 3-5-
lobed, the lobes irregularly cut and toothed, often mottled. Sepals
white, spreading. Seeds oblong, smooth, mottled. In dry woods S.*

54. ANACARDIACEJE. SUMAC FAMILY.

Trees or shrubs, with resinous, acrid, or milky sap. Leaves
simple, of 3 leaflets or pinnately compound, alternate, with-
out stipules. Flowers perfect or imperfect, small. Calyx
3-5-parted, persistent. Petals 3-5 or wanting. Stamens as
many as the sepals or sometimes twice as many, inserted in
the base of the calyx, distinct. Ovary free, 1-celled, styles
1-3. Fruit a 1-seeded stone-fruit.*

RHUS, L.

Trees or shrubs. Leaves of 3 leaflets or odd-pinnate.
Flowers in spikes or panicles. Calyx mostly 5-parted.
Petals and stamens 5. Pistil 1, sessile ; styles 3, terminal.
Fruit small, smooth or downy.*

1. R. glabra, L. SUMAC. A shrub or small tree, sometimes
25-30 ft. high ; branches downy. Leaves odd-pinnate, main midrib
downy and wing-margined ; leaflets 9-21, ovate-lanceolate, acute at
the apex, inequilateral, entire or slightly toothed, smooth and green

138 FOUNDATIONS OF BOTANY

above, pale and downy beneath. Panicle often large and spreading ;
flowers somewhat monoecious. Fruit red, hairy, acid. Open woods.*

2. R. typhina, L. STAGHORN SUMAC. A small tree, 20-40 ft.
high; branches and petioles closely velvety-hairy. Leaves odd-pin-
nate, leaflets 17-27, lanceolate-oblong, taper-pointed at the apex,
very obtuse at the base, sharply serrate, smooth above, pale and
downy beneath. Flowers somewhat monoecious, in dense terminal
panicles. Fruit red, with crimson hairs. Dry hillsides N". and E.*

3. R. Toxicodendron, L. POISON VINE, POISON IVY, MERCURY,
BLACK MERCURY. Stem a woody vine climbing high by aerial
rootlets, or sometimes short and erect. Leaves petioled, of 3 leaflets,
downy; leaflets ovate or oval, taper-pointed, entire or somewhat
dentate, often angled or lobed. Flowers dioecious, in loose axillary
panicles. Fruit nearly white, smooth. Common in open woods and
along fences. Plant poisonous to the touch.*

4. R. venenata, L. POISON SUMAC, POISON DOGWOOD. A very
smooth shrub with gray bark, 6-18 ft. high. Leaves large and
glossy, with 7-13 obovate-oblong, entire leaflets. Flower-clusters
loosely-flowered, axillary panicles. Fruit smooth, greenish-yellow.
Swamps and wet openings in woods N. and E. Plant more poison-
ous than the preceding species,

55. AQUIFOLIACE^E. HOLLY FAMILY.

Trees or shrubs. Leaves simple, alternate, petioled ; stip-
ules small or wanting. Flowers small, greenish, clustered
or solitary in the axils, usually dioecious. Calyx 4-9-parted.
Petals 4-9, somewhat united at the base. Stamens inserted
in the tube of the corolla and alternate with its lobes. Ovary
free, 4-9-celled, with a single ovule in each cell. Fruit a
berry-like stone-fruit, 4-9-seeded.*

ILEX, L.

Small trees or shrubs. Leaves usually leathery, often per-
sistent and evergreen ; stipules minute. Flowers axillary,
4-9-parted, the fertile often solitary and the staminate clus-
tered. Fruit a stone-fruit with 4-9 nutlets.*

1. I. opaca, Ait. HOLLY. Trees with smooth, light-colored bark,
and hard, very white wood ; young twigs downy. Leaves leathery,
oval or ovate, margin prickly-toothed, dark green and shining

DICOTYLEDONOUS PLANTS 139

above, paler and sometimes slightly downy beneath. Peduncles
short, bracted. Flowers 4-parted, staminate flowers in small cymes,
the pistillate usually solitary. Fruit bright red. Damp, sandy soil
E. and S.*

2. I. decidua, Walt. DECIDUOUS HOLLY. Small trees; twigs
smooth. Leaves thin, obovate, obtuse or sometimes acute at the
apex, scalloped, smooth, deciduous. Flowers in sessile clusters,
4-6 parted. Fruits very numerous, bright red. On low ground S.*

3. I. verticillata, Gray. BLACK ALDER, WINTERBERRY. * A much-
branched shrub 6-8 ft. high. Leaves thin, oval or obovate, taper-
pointed, serrate, 1^-2 in. long. Flowers greenish-white, on very
short peduncles. Fruit bright red, 1, 2, or 3 in a leaf -axil, remain-
ing long after the leaves have fallen. Swampy ground and damp
woods and thickets.

56. CELASTRACEJE. STAFF-TREE FAMILY.

Trees or shrubs, sometimes climbing. Leaves simple, oppo-
site or alternate. Flowers small, in cymes. Calyx small,
4-5-lobed, persistent. Petals 4-6, short. Stamens 4-6,
alternate with the petals and inserted with them on a disk.
Ovary sessile, 3-5-celled ; style entire or 3-5-cleft ; ovules 2
in each cell. Seeds usually covered with an appendage (aril)
growing from the hilum.

I. CELASTRUS, L.

A woody, twining shrub. Leaves alternate. Flowers
dioecious or somewhat monoecious, small, greenish, clustered
at the ends of the branches. Pod 3-celled, 3-valved, looking
like an orange-colored berry, which on opening shows the
scarlet arils of the seeds.

1. C. scandens, L. WAX-WORK, CLIMBING BITTERSWEET.
Climbing 10-15 ft. Leaves ovate-oblong, 2-4 in. long, finely ser-
rate, taper-pointed. In thickets and along fences, also planted for
the showy scarlet seeds, which retain their color for many months.

H. EUONYMUS, Tourn.

Shrubs with 4-angled branches. Leaves opposite. Flowers
in axillary, peduncled cymes, purplish or greenish, small.

140 FOUNDATIONS OF BOTANY

Sepals and petals 4-5, spreading. Stamens as many as the
petals, short. Ovary 3-5-celled, with 2 ovules in each cell.
Seeds enclosed in a red, fleshy pulp.*

1. E. americanus, L. STRAWBERRY BUSH. A shrub 3-8 ft.
high. Leaves short-petioled, ovate to ovate-lanceolate, acute or
taper-pointed at the apex, finely serrulate, smooth or slightly hairy.
Peduncles axillary, slender, 1-3-nowered. Flowers greenish. Capsule
3-5-angled, warty. In low, shady woods.

2. E. atropurpureus, Jacq. WAHOO. A tree-like shrub 10-15 ft.
high. Leaves oval to ovate, taper-pointed, finely serrulate, minutely
downy petioles £-f in. long. Peduncles slender, 3-forked, several-
flowered. Flower purplish ; capsule deeply 3-5-lobed, smooth.
River banks.

57. STAPHYLEACE.35. BLADDER-NUT FAMILY.

Shrubs. Leaves pinnately compound, with stipules, and
the leaflets with little individual stipules (stipels). Flowers
regular and perfect. Calyx-lobes 5. Petals 5, inserted in or
around a saucer-shaped disk. Stamens 5, alternate with the
petals, perigynous. Ovary 2-3-celled, with the carpels more
or less distinct ; ovules several ; styles 2-3, cohering some-
what below. Fruit usually 1-few-seeded.

STAPHYLEA, L.

Calyx deeply 5-parted, the lobes appearing like separate
sepals, erect. Petals spatulate, borne on the rim of the thick
disk. Pod large, papery, 3-celled, finally opening at the top.
Seeds 1-4 in each cell, bony.

1. S. trifolia, L. AMERICAN BLADDER-NUT. A shrub 6-12 ft.
high, with smooth, slender, greenish striped, at length gray, branches.
Leaves long-petioled, with 3 ovate, taper-pointed, finely serrate leaf-
lets. Damp thickets.

58. ACERACE^). MAPLE FAMILY.

Trees or shrubs, with abundant, often sugary sap. Leaves
opposite, simple and palinately lobed, or pinnate, without

DICOTYLEDONOUS PLANTS 141

stipules. Flowers regular, mostly somewhat monoecious or
dioecious, in axillary and terminal cymes or racemes. Calyx
4-9-parted. Petals as many as the lobes of the calyx or
none. Stamens 4-12, hypogynous. Ovary 2-celled ; styles 2.
Fruit a double key.*

ACER, Tourn.
Characteristics of the genus as above given for the family.

1. A. saccharinum, L. (A. dasycarpum, Ehrh.). WHITE MAPLE,
RIVER MAPLE. A tall tree with the main branches slender and
rather erect. Leaves very deeply 5-lobed, with the notches rather
acute, silvery-white, and when young downy on the lower surface,
the divisions narrow, coarsely cut and toothed. Flowers greenish,
in umbel-like clusters, appearing long before the leaves. Petals
absent. Fruit woolly at first, then smooth, with diverging wings,
the whole 2-3 in. long. Common on river banks S. and W., also
planted for a shade-tree, but not safe, as the branches are easily
broken off by the wind.

2. A. rubrum, L. RED MAPLE. A small tree with red or purple
twigs. Leaves simple, broadly ovate, palmately 3-5-lobed or some-
times merely serrate or cut-toothed, taper-pointed at the apex,
rounded or heart-shaped at the base, smooth or downy, becoming
bright red in autumn. Flowers appearing before the leaves on erect,
clustered pedicels. Petals red or yellow, oblong or linear. Fruiting
pedicels elongated, and drooping. Key red, smooth, wings about an
inch long. Swamps and river banks E.*

3. A. saccharum, Marsh (A. saccharinum, Wang.). SUGAR MAPLE.
A large tree. Leaves simple, palmately lobed, truncate or heart-
shaped at the base, lobes sinuate-toothed and acuminate, pale and
slightly downy beneath. Flowers appearing with the leaves, on
clustered drooping pedicels. Calyx bell-shaped, fringed. Petals
none. Keys smooth, wings about 1-1^ in. long. In cold woods,
more abundant northward. The sap of this tree is the principal
source of maple sugar, and some forms of the tree produce the
curled maple and bird's-eye maple used in cabinet-making.*

4. A. Pseudo-Platanus, L. SYCAMORE MAPLE. Easily recognized
by its drooping clusters of rather large green flowers, which appear
with the leaves. Cultivated from Europe.

5. A. platanoides, L. NORWAY MAPLE. A large tree, with
milky sap, which exudes from broken shoots or leafstalks in the
spring. Cultivated from Europe ; a very desirable shade-tree.

6. A. Negundo, L. Box ELDER. A small tree. Leaves opposite,

142 FOUNDATIONS OF BOTANY

pinnately 3-5-foliate ; leaflets ovate, lobed, toothed or entire, downy
when young. Flowers dioecious, appearing from lateral buds before
or with the leaves ; the staminate on long and drooping pedicels,
the pistillate in drooping racemes. Keys smooth, l-l£ in. long.
River banks. Often cultivated as a quick-growing shade-tree.*

59. HIPPOCASTANACEJE. BUCKEYE FAMILY.

Trees or shrubs. Leaves opposite, long-petioled, palmately
compound. Flowers showy, somewhat monoecious, in termi-
nal panicles. Calyx 5-lobed, oblique. Petals 4-5, unequal.
Stamens 5-8, hypogynous. Pistil 1 ; ovary 3-celled, 2 ovules
in each cell; style slender. Fruit a 1-3-celled, leathery
capsule, 1-3-seeded. Seeds with a large scar.*

JESCULUS, L.

Characteristics of the genus as above given for the family.

1. M. Hippocastanum, L. HORSE-CHESTNUT. A round-topped
tree with frequently forking branches and stumpy twigs. Leaves
very large, with 7 straight-veined leaflets. Flowers large and showy.
Corolla open and spreading, of 5 white petals, spotted with purple
and yellow. Stamens with long, curved filaments. Fruit large, cov-
ered with stout, soft prickles when young. Cultivated from Asia.

2. JE. glabra, Willd. OHIO BUCKEYE. A large tree, not unlike
a horse-chestnut. Leaflets generally 5. Flowers small. Corolla of
4 upright, pale yellow petals. Stamens curved, about twice as long
as the petals. Fruit prickly at first. River banks.

3. M. flava, Ait. SWEET BUCKEYE. Varying in size from a
low shrub to a tall tree. Leaves with 5-7 leaflets. Flowers in a
short, dense panicle. Petals 4, in 2 unlike pairs, bending inward,
blades of the longer pair very small. Fruit not prickly. Woods
W. and S.

4. JE. Pavia, L. RED BUCKEYE. Shrubs ; stems erect, branched,
4-8 ft. high. Leaflets usually 5, lanceolate to narrowly oval, taper-
pointed at both ends, finely serrate, smooth or nearly so. Flowers
in dense, erect panicles, bright red. Stamens rather longer than
the petals. Fruit nearly smooth. Common in open woods.*

DICOTYLEDONOUS PLANTS 143

60. BALSAMINACEJE. BALSAM FAMILY.

Tender, fleshy-stemmed, annual herbs. Leaves simple, with-
out stipules. Flowers perfect, irregular. Sepals usually 3,
the largest one with a spur. Petals 3. Stamens 5, distinct
or nearly so. Ovary 5-celled, bursting when ripe into 5
valves.

IMPATIENS, L.

Characteristics of the genus those above given for the
family. Fruit a capsule (very fleshy in our species), which
when ripe bursts open with considerable force, throwing the
seeds about.

1. I. aurea, Muhl. (I. pallida, Nutt.). WILD BALSAM. LADY'S-
SLIPPER. Stem 3-5 ft. high, branching. Leaves oblong-ovate, 2-6
in. long, the lower often loiig-petioled, the upper nearly sessile.
Peduncles axillary, 1-3 in. long, slender, 2-5 flowered. Flowers
pale yellow, slightly dotted with brownish-red. Sac of the large
sepal broader than it is long, ending in a recurved spur about ^ in.
long. Damp, shaded ground, not very common.

2. I. biflora, Walt. (I. fulva, Nutt.). WILD BALSAM, LADY'S-
SLIPPER, JEWEL WEED, SNAP WEED, KICKING COLT. Stem 2-4 ft.
high, branching. Leaves rhombic-ovate, 1-4 in. long. Peduncles
about 1 in. long, generally 2-3-flowered. Flowers orange-color, with
many pretty, large, reddish-brown spots. Sac longer than it is broad,
ending in a recurved spur about ^ in. long. Damp, shaded ground,
commoner than No. 1 and usually blossoming earlier.

61. RHAMNACE-/E. BUCKTHORN FAMILY.

Trees or shrubs. Leaves simple, often 3-5-nerved ; stipules
small. Flowers small, sometimes imperfect, green or yellow.
Calyx 4-5-lobed. Petals 4, 5, or absent, inserted on a disk at
the throat of the calyx, very small, hooded, usually with
claws. Stamens 4-5, inserted with the petals and opposite
them, often enclosed by the petals ; filaments awl-shaped ;
anthers small, versatile. Ovary 3-celled, 3-ovuled.

144 FOUNDATIONS OF BOTANY

I. BERCHEMIA, Necker.

Shrubs ; stems twining or erect. Leaves alternate, promi-
nently pinnate-veined, stipules minute. Flowers in axillary
or terminal panicles, or rarely solitary. Calyx-tube hemi-
spherical, 5-lobed. Petals 5, sessile, concave, as long as the
calyx. Ovary 2-celled, half-inferior ; stigmas 2. Fruit an
oval, 2-seeded stone-fruit.*

1. B. volubilis, DC. SUPPLE-JACK, RATTAN-VINE. Woody, often
twining high ; older bark yellowish, twigs purple, wood very tough.
Leaves ovate or oval, acute or obtuse, cuspidate at the apex,
rounded at the base, wavy on the margins, green above, pale beneath.
Flowers in small panicles. Fruit purple. In moist woods and along
streams S.*

H. RHAMNUS, L.

Leaves alternate, deciduous. Flowers in small, axillary
cymes, often imperfect. Petals 4-5 or wanting. Stamens 4
or 5, very short. Stone-fruit, 2-4-seeded.

1. R. lanceolata, Pursh. A tall shrub. Leaves with short peti-
oles, taper-pointed or somewhat obtuse, very variable in size, smooth
or nearly so above, more or less downy beneath, finely serrate.
Flowers 2 or 3 together in the axils, greenish, about £ in. in diame-
ter, usually dioecious, appearing at the same time as the leaves.
Calyx 4-lobed. Petals 4. Stamens 4. Fruit black, about £ in. in
diameter. Hills and river banks.

2. R. caroliniana, Walt. CAROLINA BUCKTHORN. A small tree
with black bark and very hard wood ; twigs finely downy. Leaves
alternate, prominently veined, elliptical to broadly oval, entire or
obscurely serrate, smooth or sometimes downy below ; petioles slen-
der, downy. Flowers in axillary, peduncled umbels ; petals minute.
Fruit globose, £-£ in. in diameter, 3-seeded. Seeds smooth. On
river banks.*

m. CEANOTHUS, L.

Shrubs. Leaves alternate, petioled. Flowers perfect, in
terminal panicles or corymbs formed of little umbel-like clus-
ters. Calyx-tube top-shaped or hemispherical, with a 5-lobed
border. Petals 5, with hoods, on slender claws. Stamens 5,
filaments long and thread-like. Fruit dry, 3-lobed, splitting
when ripe into 3 carpels.

DICOTYLEDONOUS PLANTS 145

1. C. americanus, L. NEW JERSEY TEA, RED ROOT. Shrub,
with many branching stems, 1-3 ft. high, from a deep red root.
Leaves 1-3 in. long, ovate or nearly so, acute or taper-pointed at the
tip, obtuse or somewhat heart-shaped at the base, downy beneath,
serrate, 3-nerved. Flowers small, white.

62. VITACE^:. VINE FAMILY.

Shrubs, with the stem swollen at the insertion of the peti-
oles and climbing by tendrils borne opposite the leaves.
Leaves alternate, with stipules simple or compound. Flowers
small, greenish, generally in clusters, borne in similar posi-
tions to the tendrils, hypogynous or nearly so. Sepals, petals,
and stamens 4-5. Carpels 2, each 2-ovuled. Calyx very
small. Corolla deciduous, the petals often hooded. Stamens
opposite the petals. A disk inside the calyx bears nectar and
its lobes alternate with the stamens. Fruit a berry.

I. VITIS,Tourn.

Climbing woody vines ; stems with tumid joints, climbing
by tendrils opposite some of the leaves. Leaves simple,
palmately veined or lobed ; stipules small, soon deciduous.
Flowers mostly somewhat monoecious or dioecious. Petals
often united at the apex and not expanding. Stamens in-
serted between the lobes of the disk. Ovary usually 2-celled,
4-ovuled. Fruit juicy, 1-4-seeded.*

1. V. labrusca, L. Fox GRAPE. Stems climbing high, often
1 ft. or more in diameter ; bark shreddy, coming off in long strips,
young branches woolly. Leaves broadly heart-shaped, more or less
deeply 3-5-lobed, mucronate-dentate, very woolly when young,
becoming smooth above. Panicles of pistillate flowers compact, of
staminate flowers looser. Fruit about £ in. in diameter, dark pur-
ple or sometimes nearly white. In rich woods E., S., and SW. Many
of the cultivated varieties, Concord, Niagara, etc., have been devel-
oped from this species.*

2. V. aestivalis, Michx. SUMMER GRAPE. Stem climbing high ;
bark shreddy. Leaves broadly heart-shaped, 3-5-lobed, the lobes
dentate, notches rounded, white-woolly when young, often nearly
smooth when old ; tendrils or paniqles opposite 2 out of every 3

146 FOUNDATIONS OF BOTANY

leaves, panicles long and slender. Fruit dark blue, small, very acid.
In rich woods E. and S.*

3. V. cordifolia, Michx. FROST GRAPE, CHICKEN GRAPE.
Leaves rather smooth, thin, and shining, either not lobed or some-
what 3-lobed, heart-shaped, with the notch at the base deep and
acute, taper-pointed, with large, sharp teeth. Flower-clusters large
and loose. Grapes shining black, very sour, not ripening until after
frosts ; seeds 1 or 2, rather large. Moist thickets and banks of
streams S.

4. V. rotundifolia, Michx. MUSCADINE GRAPE. Stem climbing
high ; joints short ; bark not shreddy ; wood very hard, often pro-
ducing long, aerial roots. Leaves orbicular, heart-shaped at the
base, coarsely toothed, nearly or quite smooth. Panicle small.
Grapes few in a cluster, large. The original form of the Scupper-
nong grape S.*

II. AMPELOPSIS, Michx.

Woody vines, climbing by tendrils and rootlets. Leaves
palmately compound. Flowers in compound cymes, perfect
or somewhat monoecious. Petals 5, distinct, spreading ; disk
none. Stamens 5. Ovary 2-celled, 4-ovuled. Fruit a 1-4-
seeded berry, not edible.*

1. A. quinquefolia, Michx. VIRGINIA CREEPER. WOODBINE.

Stem usually climbing high, but sometimes short and prostrate,
often producing many adventitious aerial roots which assist the vine
in holding to a support ; tendrils usually terminating in flat, adhesive
disks. Leaves palmately compound, of 5 oval leaflets, coarsely and
unevenly toothed above, usually entire below, smooth or slightly
downy. Cymes large and spreading when mature ; pedicels red.
Berries small, dark blue. Common in rich woods.*

2. A. tricuspidata, Sieb. and Zucc. JAPANESE IVY, BOSTON IVY.
A freely branching, hardy climber. Tendrils numerous, branching
with closely adhesive disks. Leaves occasionally with 3 leaflets, but
usually with only one, which is jointed with the main petiole and
in autumn falls before the petiole ; leaflet 3-lobed or only scalloped,
roundish-ovate or heart-shaped, rather thick and shining. Culti-
vated from Japan.

63. TILLAGES. LINDEN FAMILY.

Trees or shrubs, rarely herbs. Leaves alternate, with
stipules. Flowers perfect in cymes, the latter usually in

DICOTYLEDONOUS PLANTS 147

corymbs or panicles. Sepals 5. Petals 5 or fewer or wanting.
Stamens many, inserted on a swollen disk. Ovary 2-10-celled,
with 1 or more ovules in each cell. Fruit 1-12-celled, dry or
berry-like.

TILIA, Tourn.

Trees with rough gray bark on the trunk ; bark of the twigs
smooth, lead-colored ; wood white and soft. Leaves cordate,
usually inequilateral. Cymes axillary or terminal, peduncles
adnate to a large, prominently veined leaf-like bract. Flowers
yellowish-white. Sepals 5. Petals 5. Stamens many, in 5
groups. Ovary 5-celled, with 2 ovules in each cell ; stigma
5-lobed. Capsule 1-celled, 1-2-seeded ; peduncle and bract
deciduous with the matured fruit, the bract forming a wing
by which the fruit is often carried to a considerable distance.*

1. T. pubescens, Ait. BASSWOOD. A tree of medium size ; leaves
ovate, acuminate at the apex, obtuse and oblique at the base,
mucronate-serrate, woolly on both sides or smooth above when old ;
flowers fragrant, floral bract 2-3 in. long, usually rounded at the
base. Fruit globose, about \ in. in diameter. In rich woods. Bees
gather large quantities of nectar from the flowers.*

2. T. americana* L. BASSWOOD, WHITEWOOD. A large tree,
sometimes 125 ft. high. Leaves larger than in No. 1 (2-5 in. wide),
often unsymmetrical, heart-shaped or truncate at the base, sharply
toothed. Floral bract often narrowed at the base. Fruit somewhat
ovoid, £ in. or more in diameter. Common in rich woods ; occurs
farther N. than No. 1.

3. T. europsea, L. EUROPEAN LINDEN. A good-sized tree.
Leaves roundish, obliquely heart-shaped, abruptly taper-pointed,
finely toothed. Flowers differing from Nos. 1 and 2 in the absence
of petal-like scales at the bases of the stamens. Cultivated from
Europe.

64. MALVACEAE. MALLOW FAMILY.

Herbs or shrubs, with simple, alternate, palmately-veined
leaves, with stipules. Flowers regular. Sepals 5, often
surrounded by an involucre at the base. Petals 5. Stamens
numerous, monadelphous. Pistils several, more or less dis-
tinct. Fruit a several-celled capsule or a collection of 1-seeded
carpels.

148 FOUNDATIONS OF BOTANY

I. MALVA, L.

Calyx 5-cleft, with a small, 3-leaved involucre. Petals
obcordate or truncate. Styles many, slender, with stigmas
running down the sides. Carpels many, 1-seeded, arranged
in a circle and separating from each other, but not opening
when ripe.

1. M. rotundifolia, L. COMMON MALLOW, CHEESES (from ap-
pearance of the unripe fruit). A common biennial or perennial
weed, with nearly prostrate stems. Leaves long-petioled, round-
kidriey-shaped, with crenate margins. Flowers small, whitish, on
long peduncles.

2. M. sylvestris, L. HIGH MALLOW. Biennial or perennial.
Stem erect, 2-3 ft. high. Leaves 5-7 lobed. Flowers purplish,
larger than those of the preceding species.

H. ABUTILON, Tourn.

Calyx 5:cleft, the tube often angled. Styles 5-20, with
knobbed stigmas. Carpels as many as the styles, arranged in
a circle, each l-celled, 3-6-seeded, and opening when ripe by
2 valves.

1. A. striatum, Dicks. TASSEL TREE, FLOWERING MAPLE. A

shrub 5-10 ft. high. Leaves maple-like. Flowers showy, solitary,
nodding on slender peduncles. Corolla not opening widely, orange,
striped with reddish-brown veins. Column of stamens projecting
beyond the corolla like a tassel. Cultivated in hothouses. From
Brazil.

65. HYPERICACE^. ST. JOHNSWORT FAMILY.

Herbs, shrubs, or trees. Leaves opposite, often covered
with translucent or dark dots, entire or with glandular teeth,
without stipules. Mowers usually in terminal cymes. Sepals
5, rarely 4. Petals as many as the sepals, hypogynous.
Stamens usually many, more or less grouped in bundles,
anthers versatile. Pod 1-celled, with 2-5 parietal placentse
and the same number of styles, or else 3-7-celled, splitting
along the partitions.

DICOTYLEDONOUS PLANTS 149

HYPERICUM, L.

Herbs, shrubs, or small trees. Leaves sessile, often dotted.
Flowers yellow, perfect.

1. H. perforatum, L. COMMON ST. JOHNSWORT. Perennial.
Stem erect, 1-3 ft. high, 2-ridged, much branched. Leaves linear or
oblong, obtuse, with translucent veins and dots. Cymes grouped in
corymbs, many-flowered. Flowers 1 in. in diameter. Sepals acute.
Petals much longer than the sepals, oblique at the tip and irregularly
fringed. A common weed in meadows and pastures E. and N.

2. H. nudicaule, Walt. ORANGE-GRASS, PINE-WEED. Low (4-9 in.
high), slender annual, with erect, angled or almost winged wiry stem
and branches. Leaves minute, awl-shaped scales. Corolla about
\ in. in diameter, usually closing by or before midday. Sandy
banks and roadsides.

66. VIOLACE^. VIOLET FAMILY.

Herbs, with simple, alternate leaves, with stipules. Calyx
of 5 persistent sepals. Corolla of 5 petals, somewhat irreg-
ular, one petal with a spur. Stamens 5, short, the filaments
often cohering around the pistil (Fig. 17). Style generally
club-shaped, with a one-sided stigma, with an opening leading
to its interior. Pod 1-celled, splitting into 3 valves, each
bearing a placenta. The seeds are often dispersed by the
splitting of the elastic valves (Fig. 17).

VIOLA, Tourn.

Sepals ear-like at the base. Petals somewhat irregular,
some of them bearded within, thus affording a foothold for
bees, the lowest one with a spur at the base. Stamens not
cohering very much, the two lowermost with spurs which
reach down into the spur of the lowest petal. Many species
bear inconspicuous apetalous flowers later than the showy
ordinary ones and produce most of their seed from these
closed, self-fertilized flowers. (See Part I, Ch. XXVIII.)

150 FOUNDATIONS OF BOTANY

§ 1. Stemless perennials.

1. V. pedata, L. BIRD-FOOT VIOLET, HORSESHOE VIOLET, SAND
VIOLET. Rootstock stout, upright, not scaly. Leaves all palmately
5-9-parted into linear or linear-lanceolate divisions. Flowers showy,
about 1 in. broad, pale violet to whitish ; petals not bearded.

2. V. palmata, L. COMMON BLUE VIOLET. Rootstock stout' and
scaly. Earlier leaves roundish heart-shaped or kidney-form and cre-
nate, with the sides rolled in at the base when young. The later
ones variously cleft or parted. Flowers dark or light blue, some-
times whitish; the lateral petals bearded.

Variety cucullata, Gray. COMMON BLUE VIOLET, HOOD-LEAF
VIOLET. Later leaves remaining nearly crenate, like the earlier
ones, in rich soil becoming very luxuriant.

3. V. sagittata, Ait. ARROW-LEAVED VIOLET, SPADE-LEAF VIO-
LET. Leaves very variable, ranging in shape from oblong-heart-

FIG. 17. — Viola tricolor.
A, stamens and pistil ; S, pistil with stamens removed ; C, pod split open.

shaped to triangular-halberd-shaped, very often with an arrow-
shaped base, the earlier ones on short, margined petioles, the later
frequently long-petioled. Flowers rather large, otherwise much as
in the preceding species. Variable and perhaps an aggregate of
several distinct species.

4. V. blanda, Willd. SWEET WHITE VIOLET. Rootstock long,
slender, and creeping. Leaves roundish heart-shaped or kidney-
shaped. Flowers rather small, whitish, sweet-scented, generally
beardless, with the lowermost petal exquisitely veined with dark
purple lines. In damp or marshy ground.

DICOTYLEDONOUS PLANTS 151

§ 2. Leafy-stemmed perennials.

5. V. pubescens, Ait. DOWNY YELLOW VIOLET. Soft, downy,
6-12 in. high. Leaves broadly heart-shaped, toothed, with large
stipules. Flowers yellow, with a short spur.

6. V. canadensis, L. CANADA VIOLET. Stems very leafy, smooth,
1 ft. or more high. Leaves heart-shaped, taper-pointed, serrate.
Flowers large and handsome ; petals white, or nearly so, inside, the
upper ones usually violet-tinged beneath, lateral petals bearded.

§ 3. Leafy-stemmed, from an annual, biennial, or occasionally short-
lived perennial root: stipules about as large as the leaves.

7. V. tricolor, L. PANSY, HEART'S-EASE.. Stem branching,
angular, hardly erect. Leaves variable, more or less ovate, crenate.
Flowers large (often more than 1 in. across), flattish, short-spurred,
exceedingly variable in color. Cultivated from Europe.

Variety arvensis. JOHNNY-JUMP-UP, LADY'S-DELIGHT. A small
flowered variety. Introduced in gardens and sometimes appearing
like a native plant.

67. PASSIFLORACEJE. PASSION-FLOWER FAMILY.

Shrubs or herbs, climbing by axillary tendrils. Leaves
alternate, simple, mostly 3-lobed. Flowers axillary, on jointed
peduncles, solitary or few together, perfect, regular, often
showy. Calyx-tube 4-5-lobed, persistent. Petals usually 5,
inserted on the throat of the calyx-tube, which is fringed
with a crown of 1-3 rows of long and slender filaments.
Stamens 5, their filaments united, and enclosing the stalk of
the ovary. Styles 1-5 ; ovary with 3-5 parietal placentae.
Seeds numerous, fruit fleshy.

PASSIFLORA.

Characters of the family.

1. P. incarnata, L. PASSION-FLOWER. Perennial. Stem often
20-30 ft. long, somewhat angled or striate, smooth below, downy
above. Leaves broadly heart-shaped, palmately 3-5-lobed, the lobes
acute, finely serrate, usually heart-shaped at the base ; petiole bearing

152 FOUNDATIONS OF BOTANY

2 oval glands near its summit. Flowers 2-3 in. wide, solitary;
peduncles 3-bracted, longer than the petioles; calyx-lobes with a
small horn-like appendage on the back near the apex, white within.
Petals and crown purple and white. Fruit yellow, about the size
and shape of a hen's egg, edible. Seeds with a pulpy aril. Com-
mon along fence-rows and embankments S.*

2. P. lutea, L. YELLOW PASSION-FLOWER. Perennial. Stem
slender, smooth, 6-10 ft. long. Leaves broadly heart-shaped, 3-lobed
at the summit, entire, often mucronate ; stipules small ; petioles
without glands. Peduncles longer than the leaves, usually in pairs.
Flowers greenish-yellow, £-f in. wide. Fruit purple, oval, \ in.
long. Woods and thickets S.*

68. BEGONIACEJE. BEGONIA FAMILY.

Chiefly perennial herbs or low shrubs, with fleshy or very
juicy stems. Leaves alternate, generally heart-shaped at the
base, often very un symmetrical; stipules deciduous. Flowers
monoecious, in cyrnes or other clusters, on axillary peduncles.
Stamens many (Fig. 18). Pistillate flowers with the floral
envelopes borne on the ovary ; ovary 3-angled or 3-winged
(Fig. 18), very many-seeded.

BEGONIA, L.

Flowers with the calyx and corolla of the same color,
staminate and pistillate ones both occurring in the same clus-
ter. Sepals usually 2. Petals 2 or in the fertile flowers 3 or
4, sometimes wanting. Stamens many in a cluster, with short
filaments. Styles of the fertile flowers 3, often with long,
twisted stigmas (Fig. 18, (7). The genus contains a great num-
ber of species and varieties, cultivated from tropical or sub-
tropical regions, of which only a few of the commonest are
here described.

1. B. Rex, Putz. Herb, stemless or nearly so, from a fleshy root-
stock. Leaves large, taper-pointed, very unequally heart-shaped, the
margin sinuous, often bristly fringed, upper surface wholly silvery or
mottled silvery and dark green, lower surface green or reddish or of
both colors. Flowers few, large (1^ to If in. in diameter), varying
from yellow to pinkish. Cultivated from the Himalayas ; many
varieties.

DICOTYLEDONOUS PLANTS

153

2. B. manicata, Cels. Herb, with a short and fleshy stem. Leaves
very unevenly heart-shaped, taper-pointed, the margins bristly
fringed and sometimes with very remote teeth, upper surface dark
green, lower surface and petioles partly covered with long fringed
scales, stipules larger and fringed. Flowers flesh-colored, handsome,
in a loose panicle borne on a long peduncle. Cultivated from Mexico.

3. B. coccinea, Hook. Tall, 3-10 ft. high, somewhat shrubby,
often with many erect, smooth stems from the same root. Leaves

CD B

FIG. 18. — Begonia Flowers.

A, staminate flower ; B, pistillate flower ; C, twisted stigmas, enlarged ; D,
cross-section of ovary ; o, ovary ; s, sepals ; p, petals.

broadly and unevenly lanceolate or ovate-lanceolate, half -heart-shaped
or broadly one-eared at the base, acute, nearly or quite entire, smooth,
dull green above, sometimes tinged with reddish below. Peduncles
several-many-flowered, reddish, slender, somewhat nodding. Flowers
showy, medium sized, scarlet. Fruit showy, scarlet, very broadly
winged. Cultivated from Peru. [Often called B. rubra.~\

4. B. incarnata, Link and Otto. Herbaceous or mainly so, rather
tall (2-4 ft.), stems clustered, slightly reclining, hairy when young,

154 FOUNDATIONS OF BOTANY

at length smoother. Leaves broadly and very unequally ovate-
lanceolate, tapering toward the tip but at the extremity somewhat
blunt, half-heart-shaped at the base, somewhat lobed and sinuate-
toothed, rough-hairy above and below and on the petioles, dark
green above with coppery streaks along the veins. Flowers on
short peduncles, few, of medium size, beautiful rose-pink in the bud,
becoming almost white, thickly covered outside with soft, moss-like
hairs. Cultivated from Mexico. [Often called B. metaUica.~\

5. B. semperflorens, Link and Otto. Stems smooth, herbaceous,
rather fleshy, branching near the ground and reclining. Leaves
obtuse or nearly so, broadly ovate, somewhat unevenly heart-shaped
or tapering at the base, irregularly serrate, or scalloped and wavy,
smooth, dark green, and very glossy above ; stipules rather large,
nearly ovate. Flowers in small, axillary clusters near the top of the
stem, whitish to crimson, about \\ in. in diameter. Ovary in fruit
very broadly winged. An easily grown but homely species. Culti-
vated from S. Brazil.

69. CACTACE^E. CACTUS FAMILY.

Plants usually with very fleshy and much thickened, often
globular or cylindrical stems (Fig. 49). Leaves usually
wanting. Flowers sessile, solitary, often very showy. Peri-
anth consisting of several rows of sepals and petals, adnate
below to the ovary. Stamens many, with slender filaments,
borne on the inside of the perianth-tube. Style 1 ; stigmas
numerous ; ovary 1-celled, many-ovuled. Fruit a many-
seeded berry.

I. OPUNTIA, Tourn.

Stem composed of a series of flattened joints, which are
usually leafless when full grown. Leaves very small, awl-
shaped, spirally arranged, appearing on the young joints, but
soon dropping off, with barbed bristles and sometimes spines
in their axils. Flowers yellow. Sepals and petals not much
united into a tube. Fruit often eatable.

1. 0. vulgaris, Mill. COMMON PRICKLY PEAR. Prostrate or
nearly so, pale green. Leaves about i in. long, rather scale-like ;
bristles many, with few or no spines. Flowers 2 in. or more in
diameter, with about 8 petals. Fruit about 1 in. long, crimson

DICOTYLEDONOUS PLANTS 155

when ripe, eatable. Dry rocks and sandy ground, from Massachu-
setts south along the coast.

2. 0. Rafinesquii, Engelm. Prostrate, green. Leaves £-£ in. long,
awl-shaped, spreading ; bristles often intermixed with a few small
spines and a larger one f-1 in. long. Flowers larger than in No. 1
and with 10-12 petals. Fruit about 1| in. long, much tapered at
the base. In poor soil.

3. 0. missouriensis, DC. Prostrate, light green. Leaves very
small, with bristles and 5-10 spines in their axils. Flowers 2-3 in.
in diameter. Fruit dry and spiny. Wisconsin, S. and W.

I
II. PHYLLOCACTUS.

Stems cylindrical when old, with long, flattened, fleshy but
leaf-like, sinuate or serrate branches. Flowers nearly or quite
regular, from the notches in the margins of the joints.

1. P. Ackermanni, L. Flowers very showy, bright red. Perianth-
tube shorter than the petals. Sepals scattered, small and bract-like.
Petals many, 2-3 in. long, widely spreading, somewhat channeled,
sharp-pointed. Cultivated from Mexico.

III. CEREUS, DC.

Stem more or less prismatic but strongly ridged, with bun-
dles of spines borne on the ridges, sometimes prostrate or
trailing, sometimes erect, columnar, and 50 or 60 ft. high.
Flowers usually showy, borne on the sides of the stem, gener-
ally with a rather long perianth-tube, which is covered outside
with scale-like sepals, usually with tufts of wool in their axils.
Petals many, mostly long and spreading.

1. C. speciocissimus, DC. Stems 2-3 ft. high, with 3-4 broad-
winged and sinuate ridges. Flowers open in the daytime and lasting
several days, red or crimson, very showy. Petals longer than the
tube, stamens white, drooping, very numerous. Commonly culti-
vated from Mexico.

2. C. grandiflorus, Mill. NIGHT-BLOOMING CEREUS. Stems long,
climbing by aerial roots, nearly cylindrical, but with 5 or more blunt
angles. Flowers very showy, opening only for one night, wilting
early in the morning, extremely fragrant. Sepals dull yellow. Petals
pearly white, spreading, 6-8 in. long. Cultivated from Mexico.

156 FOUNDATIONS OF BOTANY

70. (ENOTHERACE^. EVENING PRIMROSE FAMILY.

Herbs, rarely shrubs or trees. Leaves opposite or alternate,
without stipules. Flowers regular. Calyx-tube adnate to
the ovary, its margin 2-4-lobed. Petals 2-4, rarely wanting,
perigynous, quickly falling off. Stamens 1-8. Ovary usually
4-celled ; style thread-like ; stigma entire or 4-lobed ; ovules
1 or more in the inner angle of each cell. Fruit a capsule,
berry, or stone-fruit. Seeds 1 or more, smooth or hairy.

I. (ENOTHERA, L.

Herbs, rarely shrubby. Leaves alternate. Flowers large,
yellow, red, or purple. Calyx-tube 4-angled. Petals 4.
Stamens 8. Capsule usually 4-celled, many-seeded.

1. (E. fruticosa, L. SUNDROPS. Biennial or perennial. Stem
erect, often rather stout, 1-3 ft. high, downy or sometimes smooth.
Leaves lance-oblong, or in one variety linear or nearly so, usually
minutely toothed. Racemes often corymbed. Flowers open in
the daytime, showy, yellow, 1-2 in. in diameter. Pod nearly sessile,
ellipsoidal, with prominent ribs and strong wings. Dry soil, common.

2. (E. pumila, L. SMALL SUNDROPS. Much like the preceding,
but smaller. Leaves oblanceolate or oblong, entire. Flowers £-1 in.
in diameter. Pod club-shaped. In dry soil.

H. FUCHSIA, L.

Herbs, shrubs, or trees. Leaves opposite or 3 in a whorl.
Flowers showy. Calyx colored, tubular-funnel-shaped, the
tube extending much beyond the ovary, the margin 4-lobed.
Petals 4, borne in the throat of the calyx. Stamens 8, pro-
jecting outside the corolla. Capsule berry-like, ellipsoidal,
4-angled.

1. F. macrostemma, Ruiz and Pav. COMMON FUCHSIA, LADIES'
EARDROP. Smooth. Leaves slender-petioled, toothed. Flowers on
long, drooping peduncles from the axils of the leaves. Calyx-tube
oblong or a short cylinder, not as long as its spreading lobes. Petals
obovate and notched, wrapped spirally around the projecting fila-

DICOTYLEDONOUS PLANTS 157

ments and style. Found in many varieties, sometimes the calyx
white or nearly so and the petals dark or with dark calyx and light
petals. Cultivated from Chili.

m. CIRCJEA, Tourn.

Slender, erect herbs, with creeping rootstocks. Stem simple.
Leaves opposite, petioled. Flowers small, in terminal and
lateral racemes. Calyx-tube ovoid, the limb 2-parted, reflexed,
deciduous. Petals 2, inversely heart-shaped, inserted with the
2 stamens under a margin of a disk which is borne on the
pistil. Ovary 1-2-celled ; style thread-like ; stigma knobbed,
2-lobed ovules, 1 in each cell. Fruit ovoid, not splitting open,
covered with hooked bristles.

1. C. lutetiana, L. ENCHANTER'S NIGHTSHADE. Stem 1-2 ft.
high, glandular-downy. Leaves ovate, faintly toothed, long-petioled.
Flowers i in. in diameter, white or pink, on slender pedicels, jointed
at the base. Damp, shaded places ; very common.

71. ARALIACE^. GINSENG FAMILY.

Herbs, shrubs, or trees. Leaves alternate, simple or com-
pound ; stipules adnate to the petiole or wanting. Flowers
regular, in umbels or heads. Limb of the calyx borne on
top of the ovary, very short. Petals 5, very deciduous.
Stamens 5, filaments bent inward, anthers versatile. Ovary
2-celled or several-celled ; styles or stigmas as many as the
cells ; ovule 1 in each cell. Fruit a stone-fruit or berry.
[The English ivy, an important member of the family, flowers
too late for school study.]

ARALIA, Tourn.

Perennial plants with pungent or spicy roots, bark, and fruit.
Leaves once or more compound. Flowers more or less monoe-
cious, white or greenish, in umbels. Stone-fruit, berry-like.

1. A. hispida, Vent. BRISTLY SARSAPARILLA, WILD ELDER.
Stem 1-2 ft. high, rather shrubby below, with prickly bristles.
Leaves once or twice pinnate ; leaflets ovate, acute, cut-serrate and

158 FOUNDATIONS OF BOTANY

often lobed. Peduncle bearing several umbels of cream-colored
flowers, in a terminal corymb. Fruit blue-black. Dry fields and
pastures E.

2. A. nudicaulis, L. SARSAPARILLA. Perennial herb ; roots very
long, somewhat fleshy, aromatic; stem very short or none. Leaf
solitary, from a sheathing base, petioled, 6-12 in. long ; compound in
threes, each division 3-5-pinnate ; leaflets oval or ovate, taper-pointed,
finely and sharply serrate, smooth above, often downy below. Scape
nearly as long as the petiole, usually bearing 3 short, peduncled
umbels. Flowers greenish. Styles distinct. Fruit globose, black.
In rich woods.

72. UMBELLIFER^. PARSLEY FAMILY.

Herbs, usually with hollow, grooved stems. Flowers small,
generally in umbels. Calyx-tube adnate to the ovary ; limb
of the calyx either wanting or present only as a 5-toothed rim
or margin around the top of the ovary. Petals 5. Stamens 5,
inserted on the disk, which is borne by the ovary (Fig. 19).
Ovary 2-celled and 2-ovuled (Fig. 19), ripening into 2
akene-like carpels, which separate from each other. Each
carpel bears 5 longitudinal ribs, in the furrows between which
secondary ribs frequently occur. On a cross-section of the
fruit, oil-tubes are seen, traversing the interspaces between
the ribs, and near the surface of the fruit (Fig. 19). The
seeds contain a small embryo, enclosed in considerable endo-
sperm. [The family is a difficult one, since the flowers are
so much alike that the species are distinguished from each
other mainly by minute characteristics of the fruit.]

I. ERYNGIUM, Tourn.

Annual, biennial, or perennial herbs. Stems erect or creep-
ing. Leaves simple, mostly linear and spiny-toothed. Flowers
white or blue, in dense, bracted heads or spikes, flowers brac-
teolate. Calyx-teeth rigid, persistent. Petals erect, pointed.
Styles slender. Fruit top-shaped, scaly or granular, ribs want-
ing, oil-tubes usually 5, minute.*

DICOTYLEDONOUS PLANTS 159

1. E. yuccaefolium, Michx. BUTTON SNAKEROOT, RATTLESNAKE
MASTER. Perennial. Stem erect, branched above, striate, covered
with a bloom, 2-3 ft. high. Leaves linear, often 2 ft. or more in
length, rigid, covered with a bloom, parallel-veined, fringed with white
bristles. Bracts shorter than the heads, entire, bracteoles similar
but smaller. Flowers white. Fruit scaly. In damp soil.*

II. SANICULA, Tourn.

Slender, erect, perennial herbs. Eootstock short, stout,
creeping. Leaves palmately cut. Umbels small, somewhat
globular, irregularly compound ; bracts leafy ; bracteoles few ;

o- ' W A C TT B

FIG. 19. — Flower and Fruit of Umbelliferse.

A, flower of Fceniculum; JS, fruit of Heracleum ; (7, fruit of Heracleum, cross-sec-
tion ; o (in A), ovary ; d, disk ; s</, stigma ; s, stamens ; o (in J3, and C), oil-tubes ;
r, ribs. A, B, and C all enlarged.

flowers perfect or staminate, greenish, or yellowish. Calyx-
teeth as long as the small petals, sharp-pointed. Fruit ovoid,
covered with hooked prickles, ribless, each carpel with 5 oil-
tubes.

1. S. marylandica, L. SANICLE, BLACK SNAKEROOT. Stem rather
stout, 1^-4 ft. high. Leaves 3-7 -parted, the divisions irregularly
serrate or dentate and often cut. Petals greenish-white, very small.
Fruit with two slender, recurved styles at the apex. Rich woods.

III. ERIGENIA, Nutt.

A little smooth plant with a slender, unbranched stem, from
a deep, nearly globular tuber. Leaves 1 or 2, twice or thrice
compound in threes. Flowers few, small, in an imperfect
leafy-bracted umbel. Calyx-teeth wanting. Petals obovate

160 FOUNDATIONS OF BOTANY

or spatulate. Fruit smooth, roundish, notched at both ends,
the two carpels touching only at top and bottom, each with
5 slender ribs.

1. E. bulbosa, Nutt. HARBINGER OF SPRING, TURKEY PEA,
PEPPER-AND-SALT. Stem scape-like, with a leaf which forms an
involucre to the flower-cluster. Petals white, anthers brown-purple.
A pretty, though inconspicuous plant ; welcomed as one of the earliest
spring flowers S.

IV. OSMORRHIZA, Raf.

Perennials, springing from stout, aromatic roots. Leaves
compound in threes. Flowers white, in compound umbels.
Calyx-teeth wanting. Fruit linear or nearly so, tapering at
the base, with 5 equal bristly ribs, without oil-tubes.

1. 0. brevistylis, DC. HAIRY SWEET CICELY. Rather stout
and hairy, especially when young, 1^-3 ft. high. Lower leaves on
long petioles, large, twice compound in threes, the divisions ovate or
oval, cut-toothed, upper leaves nearly sessile, less compound. Umbels
with long peduncles and spreading rays. Style and its enlarged
base somewhat conical. Root nauseous. Rich woods.

2. 0. longistylis, DC. SMOOTH-LEAVED SWEET CICELY. Much
like No. 1 in general appearance. Smooth or nearly so. Style
rather thread-like. Root of a pleasant aromatic flavor (as is also
the fruit). Woods.

Caution. So many plants of this family have actively poisonous
roots and foliage that it is unsafe for any one but a botanist, who
can distinguish the poisonous species from the harmless ones, to
taste them.

V. CARUM, L.

Herbs, with slender, smooth stems. Leaves pinnately com-
pound, smooth. Umbels compound. Flowers white or yel-
lowish. Calyx-teeth minute. Fruit smooth, oblong or ovate,
with thread-like ribs ; oil-tube single in the intervals between
the ribs ; base of the styles thickened into a conical mass.

1. C. Carui, L. CARAWAY. Perennial. Leaves large, with the leaf-
lets cut into numerous thread-like divisions. Flowers white. Fruit
aromatic, used somewhat in this country and more in N". Europe for
flavoring cookies, bread, etc. Introduced from Europe.

DICOTYLEDONOUS PLANTS 161

VI. THASPIUM, Nutt.

Perennial herbs. Stem erect. Leaves 1-2, compound in
threes. Umbels compound, involucre and involucels usually
wanting. Flowers yellow or purple. Calyx-teeth small,
acute. Fruit ovoid or oblong, somewhat laterally compressed ;
carpels smooth, strongly ribbed, oil-tubes between the ribs.*

1. T. barbinode, Nutt. HAIRY MEADOW PARSNIP. Stem erect,
branching above, downy at the nodes, 2-7 ft. high. Leaves petioled,
slightly downy, leaflets mostly thin, ovate, toothed, incised or lobed
toward the apex, entire toward the base. Umbels long-peduncled,
few-rayed. Fruit oblong, lateral and central ribs strongly winged.
Along streams.*

VII. ZIZIA, Koch.

Smooth perennials. Leaves generally as in Thaspium.
Involucre wanting ; involucels of small bractlets. Umbels
compound. Flowers yellow. Calyx-teeth prominent. Fruit
more or less ovoid, smooth, with thread-like ribs, oil-tubes
large and solitary between the ribs and a little one in each
rib ; the central fruit of each umbellet sessile.

1. Z. aurea, Koch. MEADOW PARSNIP, GOLDEN ALEXANDERS.

Smooth, stem erect, 1-2 ft. high. Root-leaves mostly heart-shaped
and serrate, stem-leaves usually once compound in threes. Flowers
deep yellow. Fruit between globose and ovoid, about £ in. long, all
the ribs generally winged. Woods and thickets.

VIH. PASTINACA, L.

A tall, smooth biennial with a stout, grooved stem. Leaves
pinnate. Flowers yellow, in large umbels, with hardly any
involucre. Calyx-teeth wanting. Fruit oval, very flat, with
a thin wing, oil-tubes single, running the whole length.

1. P. sativa, L. COMMON PARSNIP. Cultivated from Europe
for its large, conical, sweet, and edible roots. Also introduced in
waste places.

IX. HERACLEUM, L.

A stout perennial, with the very large leaves compound in
threes. Umbels large, compound, with the involucels many-

162 FOUNDATIONS OF BOTANY

leaved. Petals white, inversely heart-shaped, the outer ones
usually 2-cleft and larger. Calyx with 5 small teeth. Fruit
tipped with a thick, conical enlargement of the style, with
three blunt ribs on the outer surface of each carpel and a
large oil-tube in each interval between the ribs. Seeds flat.

1. H. lanatum, Michx. Cow PARSNIP. Stem grooved and woolly,
4-8 ft. high. Leaflets petioled, broad, deeply and irregularly toothed.

X. DAUCUS, L

Annual or biennial, bristly-hairy herbs. Leaves pinnately
twice or more compound, the divisions slender. Umbels com-
pound, many-rayed. Flowers small, white. Calyx-teeth slen-
der or wanting. Petals notched, the point bent inward, often
unequal. Fruit ovoid or ellipsoid, with rows of spines.

1. D. Carota, L. COMMON CARROT. Erect, 1-3 ft. high, \vith a
conical, fleshy, orange-colored root. Lower and root-leaves 2-3
pinnate. Central flower of each umbel and sometimes of each
umbellet larger and very dark purple, with the corolla irregular.
Cultivated from Europe for the edible roots; also introduced in
pastures and meadows and along roadsides E.

73. CORN ACE JE. DOGWOOD FAMILY.

Shrubs or trees, rarely herbs. Leaves opposite or alter-
nate, without stipules. Flowers small, regular, variously
clustered. Calyx-tube adnate to the ovary ; limb of the calyx
very short. Petals 4-5, borne on the margin of a disk on top
of the ovary. Stamens 4-5, inserted with the petals. Ovary
1-4-celled, with one ovule in each cell; style 1. Fruit (in
our species) a 1-2-celled and 1-2-seeded stone-fruit.

I. CORNUS, Tourn.

Trees, shrubs, or herbs. Leaves usually opposite. Flowers
in forking cymes, or in umbels or heads, each with an invo-
lucre, white or yellow. Calyx-teeth 4. Petals 4. Stamens 4.
Ovary 2-celled. Stone-fruit, ovoidal or ellipsoidal, the stone
2-celled.

DICOTYLEDONOUS PLANTS 163

1. C. canadensis, L. DWARF CORNEL, BUNCH-BERRY, PUDDING-
BERRY. Stem herbaceous, excepting at the base, low (3—9 in.), and
imbranched. Rootstock rather woody, slender, and creeping. Leaves
in. what appears to be a whorl of 4 or 6 at the summit of the stem,
sessile, ovate, oval or nearly so, acute at each end, entire, smooth or
very slightly downy. Flower-stalk slender, j— 1^ in. long, with a
whorl of 4-6 large, white, petal-like bracts, forming an involucre
round the small head of greenish flowers ; the head with its invo-
lucre appearing to others than botanists like a single flower. Fruit
nearly spherical, scarlet, about £ in. in diameter, in a close cluster,
sweet and eatable, though rather insipid. Damp woods, especially N".

2. C. florida, L. FLOWERING DOGWOOD. Small trees ; bark
rough, black. Leaves opposite, petioled, ovate to ovate-lanceolate,
entire, green and shining above, paler and often downy beneath.
Flowers small, greenish, in heads which are subtended by 4 large,
white or pink, inversely heart-shaped bracts, thickened and greenish
at the notch. Fruit ovoid, bright red. In rich woods S. and E.*

3. C. circinata, L'Her. ROUND-LEAVED DOGWOOD. A shrub
3-10 ft. high, with green, warty twigs. Leaves petioled, roundish-
oval, contracted to an abrupt point, entire, usually rounded or trun-
cate at the base, pale and soft-downy beneath. Flowers in flat
cymes, l|-2£ in. in diameter. Fruit globose, light blue, ± in. or less
in diameter. Thickets often in rocky soil N. and along Alleghany
Mountains.

4. C. sericea, L. KINNIKINNIK. A shrub, 6-10 ft. high ; twigs
purple, downy when young. Leaves opposite, petioled, ovate or
oblong, taper-pointed, smooth above, silky-downy below. Flowers
white, in rather close cymes. Fruit blue, stone somewhat oblique.
In low woods.*

5. C. asperifolia, Michx. ROUGH-LEAVED DOGWOOD. A shrub
8-12 ft. high ; twigs slender, reddish-brown, often warty, densely
downy when young. Leaves opposite, short-petioled, lance-ovate
or oblong, acute or taper-pointed, with rough down above, downy-
woolly below. Cymes flat, spreading, the peduncle and branches
covered with rough down. Flowers white. Fruit white or pale
blue, stone depressed-globose. In dry woods.*

6. C. stolonifera, Michx. RED OSIER DOGWOOD. A shrub 3-15
ft. high, with smooth, reddish-purple bark on all the younger twigs,
spreading by suckers from the base and therefore the stems usually
clustered. Leaves on rather slender petioles, acute or taper-pointed,
rounded or tapered at the base, covered at least beneath by very fine,
closely appressed hairs. Fruit white or nearly so, globose, \ in. or
more in diameter. Common in wet ground, especially N".

7. C. alternifolia, L. ALTERNATE-LEAVED DOGWOOD. A shrub
or small tree; twigs greenish, striped. Leaves alternate, often

164 FOUNDATIONS OF BOTANY

clustered at the ends of the twigs, long-petioled, oval, acute at the
apex and often at the base, minutely toothed, pale and covered with
fine, appressed hairs beneath ; cymes loose and open. Flowers white.
Fruit deep blue. Banks of streams.*

II. NYSSA, L.

Trees or shrubs. Leaves alternate, petioled, entire or few-
toothed. Flowers somewhat monoacious or dioecious, the
staminate in many-flowered heads or cymes, the pistillate in
small clusters or solitary. Calyx-tube 5-toothed or truncate.
Petals minute or wanting. Stamens 5-10. Ovary 1-celled,
1-ovuled ; style long and recurved. Fruit a 1-seeded stone-
fruit.

1. N. sylvatica, Marsh. BLACK GUM. A tree with widely
spreading branches and dark, rough bark, wood light-colored, very
tough, base of trunk often enlarged. Leaves often clustered at the
ends of the twigs, oval or obovate, taper-pointed or obtuse at the
apex, entire, smooth and shining above, downy beneath, becoming
bright red in autumn. Staminate flowers in heads. Pistillate 3-10
in a long-peduncled cluster. Fruit ovoid, dark blue or nearly black,
% in. long, stone slightly ridged. In rich, wet soil S. and E.*

2. N. uniflora, Wang. TUPELO. A large tree, similar to the
preceding. Leaves long-petioled, oval or ovate, acute at each end,
entire or coarsely toothed, the lower sometimes heart-shaped, smooth
above, downy beneath, 4-8 in. long. Staminate flowers in heads.
Pistillate flowers on long peduncles, solitary. Fruit ovoid, dark blue,
stone sharply ridged. In swamps S. and E.*

74. PYROLACEJE. PYROLA FAMILY.

Perennial herbs, evergreen or else pale and without chlo-
rophyll. Petals usually free from each other and falling off
separately after flowering. Stamens hypogynous, the anthers
without appendages and opening by pores or by a transverse
slit. Fruit a capsule containing a great number of very small
seeds.

L CHIMAPHILA, Pursh.

Low plants, nearly herbaceous, with reclining stems, from
long, horizontal, underground shoots. Leaves opposite or

DICOTYLEDONOUS PLANTS 165

whorled, leathery, shining, evergreen, on short u petioles.
Flowers fragrant, white or purplish, on a corymb or umbel
which terminates the stem. Calyx 5-cleft or 5-parted, per-
sistent. Petals 5, concave, roundish, spreading. Stamens
10, the filaments enlarged and downy in the middle, the
anthers somewhat 4-celled, opening when mature by pores at
the outer end. Style top-shaped, nearly buried in the top of
the globular ovary. Capsule erect, 5-celled.

1. C. umbellata, Nutt. PRINCE'S PINE, PIPSISSEWA. Branches
leafy, 4—12 in. high. Leaves spatulate or wedge-oblanceolate, obtuse
or nearly so, sharply serrate, very green and glossy. Flowers sev-
eral, umbelled or somewhat corymbed, white or pinkish, the anthers
violet. Dry woods, especially under pine trees.

2. C. maculata, Pursh. SPOTTED WINTERGREEN. Much resem-
bles No. 1, but has only scattered teeth on the leaves, which are
mottled with white on the upper surface and are often broad or
rounded at the base. Dry woods.

H. PYROLA, Tourn.

Biennial or perennial, almost woody herbs ; rootstock slen-
der and creeping. Leaves mostly radical, with broad petioles,
evergreen. Flowers in racemes, nodding, on a bracted scape.
Sepals 5. Corolla usually globose, of 5 free or nearly free,
roundish petals. Stamens 10, in pairs opposite the petals,
hypogynous ; anthers as in Chimaphila. Capsule globose,
5-celled, splitting into 5 valves, the latter usually with downy
edges.

1. P. elliptica, Nutt. SHIN-LEAF. Scape 5-10 in. high. Leaf-
blades obovate-oval or elliptical, rather thin, dark green, faintly
scalloped, almost always longer than their margined petioles.
Flowers greenish-white, very fragrant. Rich, usually dry woods,
especially N.

2. P. rotundifolia, L. ROUND-LEAVED WINTERGREEN. Scape
6-20 in. high. Leaf-blades roundish or oval, leathery, shining above,
faintly scalloped, often rounded at the base or almost heart-shaped,
usually shorter than the slightly margined petioles. Flowers white,
very fragrant. Varies greatly. Usually in dry woods N.

166 FOUNDATIONS OF BOTANY

HI. MONOTROPA, L.

Leafless, simple, erect, white, brown, or red root-parasites
or saprophytes or fed by slender fungus-threads which cluster
on the roots. Stem scaly, the upper scales often passing into
bracts. Flowers solitary or in spikes or racemes. Sepals or
bracts 2-5, erect, deciduous. Petals 4 or 5, erect or spreading.
Stamens 8 or 10, hypogynous, the filaments awl-shaped, anthers
kidney-shaped. Ovary 4-5-celled ; style simple ; stigma disk-
like, with 4-5 rays.

1. M. uniflora, L. INDIAN PIPE. Stem smooth, fleshy, 4-6 in.
high. Bracts ovate or lanceolate. Flower single, tubular, f-1 in.
long, inodorous. Stamens a little shorter than the petals. Capsule
angled, ^-f in. long. Whole plant waxy-white, turning black in dry-
ing. In moist, shady woods N". and E.*

2. M. Hypopitys, L. PINE-SAP. Stems single or clustered, white
or reddish, 4-8 in. high. Bracts ovate-lanceolate. Flowers several,
in a scaly raceme, fragrant, |—f in. long. Capsule oval, £ in. long.
In dry, shady woods, especially under oaks or pines.*

75. ERICACE^. HEATH FAMILY.

Usually shrubs or slightly shrubby plants. Leaves simple,
generally alternate. Corolla commonly regular, 4-5-cleft,
sometimes polypetalous. Stamens hypogynous, distinct, as
many or twice as many as the petals, the anthers mostly
opening by a hole at the end. Ovary usually with as many
cells as there are corolla-lobes j style 1. Seeds small, with
endosperm.

Shrubs or small trees. Calyx free from the ovary. Corolla hypogynous,
usually gamopetalous.

Shrubs or small trees, with showy flowers. Anthers not held
down in pockets in the corolla. Rhododendron, I.

Shrubs, with showy flowers. Anthers at first held in pocket-
like depressions in the corolla. Kalmia, II.

DICOTYLEDONOUS PLANTS 167

Shrubs, with small, mostly white, urn-shaped flowers.

Andromeda, III.
A prostrate plant, hardly at all shrubby. Leaves rather large,

often l£ in. wide, and veiny. Epigaea, IV.

A trailing plant with small (about £ in. wide), thick, evergreen

leaves. Arctostaphylos, V.

Shrubs. Calyx-tube adnate to the ovary, on which the gamopetalous
corolla and the stamens are borne. Fruit a true berry or resembling
one.

Fruit a berry-like stone-fruit, with 10 nutlets which resemble

seeds. Gaylussacia, VI.

Fruit a berry with many small seeds. Vaccinium, VII.

I. RHODODENDRON, L.

Shrubs, often much, branched. Leaves alternate, thin,
deciduous. Flowers very showy, in terminal umbels, from
scaly buds, which became well developed the previous season.
Calyx very small, 5-parted. Corolla bell-shaped, the tube
long and slender, the limb spreading and somewhat one-sided.
Stamens 5 or 10, declined ; anthers awnless. Style long and
slender, declined ; stigma knobbed. Capsule oblong or linear,
5-celled, many-seeded ; seeds very small, scale-like.

1. R. nudiflorum, Torr. WILD HONEYSUCKLE, ELECTION PINK.
A branching shrub, 4-6 ft. high ; twigs smooth or with a few coarse
hairs. Leaves obovate or oblong, ciliate-serrate, downy, becoming-
smooth above ; petioles short. Flowers appearing with or before
the leaves, pink or white, sometimes yellowish, fragrant, 1-2 in.
wide, tube downy but not glandular. Capsule erect, linear-oblong,
|-| in. long. Swamps and banks of streams; flowers extremely
variable in size and color.*

2. R. viscosum, Torr. SWAMP HONEYSUCKLE, SWAMP PINK.
A shrub, 4-6 ft. high; branches hairy. Leaves obovate, leathery,
mucronate at the apex, mostly smooth above, downy on the veins
beneath ; petioles very short. Flowers appearing later than the
leaves, white, fragrant, 1^-2 in. long; tube long, glandular-viscid;
capsule erect, ^-| in. long, bristly. In swamps.*

168 FOUNDATIONS OF BOTANY

II. KALMIA, L.

Erect and branching shrubs. Leaves alternate, opposite
or in threes, entire, leathery, evergreen. Flowers showy, in
corymbs or 1-3 in the axils. Calyx 5-parted. Corolla flat-
bell-shaped or wheel-shaped, 5-lobed. Stamens 10, the anthers
placed in pouches in the corolla, filaments straightening elas-
tically at maturity and so bringing the anthers in contact with
any large insect-visitor. Style long and slender. Capsule
globose, 5-celled, many-seeded.

1. K. angustifolia, L. SHEEP LAUREL. A shrub, 1-3 ft. high,
with smooth, nearly erect branches. Leaves petioled, opposite or in
threes, oblong, obtuse at both ends, dark green above, paler beneath.
Corymbs lateral, glandular. Flowers purple or crimson, |— ^ in
broad ; pedicels slender, recurved in fruit. Calyx downy, persistent.
Style persistent ; capsule depressed-globose. On hillsides ; abundant
northward.*

2. K. latifolia, L. CALICO BUSH, MOUNTAIN LAUREL. A shrub,
4-10 ft. high. Branches stout, smooth. Leaves mostly alternate,
petioled, elliptical or oval, acute at each end, smooth and green on
both sides. Corymbs terminal, compound. Flowers white to rose-
color, showy, 1 in. broad. Calyx and corolla glandular; pedicels long,
slender, sticky-glandular, erect in fruit ; calyx and style persistent.
Shady banks on rocky or sandy soil.*

IE. ANDROMEDA, L.

A small shrub, with scaly buds. Leaves alternate.
Flowers in nearly terminal umbels, white or pink. Sepals 4.
Corolla hypogynous, globose, with a 5-cleft, reflexed limb.
Stamens 10, hypogynous, not projecting beyond the corolla;
filaments bearded. Ovary 5-celled; style simple; stigma
obtuse or enlarged. Capsule somewhat globose, 5-valved.
Seeds small, smooth and hard.

1. A. polifolia, L.. WILD ROSEMARY. Stems long, rooting at
the base, with somewhat erect, twiggy, smooth branches, 6-18 in.
high. Leaves elliptical-lanceolate, smooth and shining, thick and
evergreen. Flowers small, purplish. Wet bogs, common N".

2. A. Mariana, L. STAGGER-BUSH. Usually smooth, 2-4 ft. high.
Leaves moderately thin and deciduous, oblong or oval, 1-3 in. long.
Flowers rather small, white or pinkish, nodding, in racemes on the

DICOTYLEDONOUS PLANTS 169

naked shoots of the preceding year. Low grounds. Foliage said to
be poisonous to young browsing animals.

IV. EPIGJEA, L.

Prostrate or trailing shrubs. Steins rusty-downy, 6-12 in.
long. Leaves alternate, leathery, evergreen. Flowers in
bracted, terminal close racemes or clusters. Calyx 5-parted,
persistent. Corolla salver-shaped, 5-lobed. Stamens 10, about
the length of the corolla-tube. Ovary 5-lobed ; style columnar ;
stigma 5-lobed. Fruit a globose, hairy, 5-celled, many-seeded
capsule.*

1. E. repens, L. GROUND LAUREL, TRAILING ARBUTUS, MAY-
FLOWER. Stems creeping, the young twigs ascending. Leaves oval
or somewhat heart-shaped, entire, netted-veined, smooth above,
rough-hairy beneath ; petioles short, rough-hairy. Racemes shorter
than the leaves. Flowers white to bright pink, £ in. broad, very
fragrant. In dry woods, often covering considerable areas.*

V. ARCTOSTAPHYLOS, Adans.

Shrubs. Leaves alternate, evergreen. Flowers pinkish or
nearly white, in terminal, bracted racemes. Calyx 4-5-parted,
persistent. Corolla 4-5-lobed, the lobes recurved. Ovary
5-10-celled, each cell containing 1 ovule. Fruit a berry-like
stone-fruit, with 5-10 nutlets.

1. A. Uva-ursi, Spreng. BEARBERRY. In trailing clumps, the
branches 1-2 ft. high. Leaves evergreen, finely woolly, obovate or
spatulate, entire, very leathery. Racemes few-flowered, very short.
Corolla urn-shaped, the teeth hairy within. Berry red, ^ in. in
diameter. Rocks and dry hilltops, especially N.

VI. GAYLUSSACIA, HBK.

Low, branching shrubs, mostly resinous-dotted. Leaves
serrate or entire. Flowers small, white or pink, in lateral,
bracted racemes, nodding ; pedicels usually 2-bracteolate.
Calyx-tube short, obconic, the lobes persistent. Corolla
ovoid to bell-shaped, 5-lobed, the lobes erect or recurved.
Stamens equal, usually included ; anthers awnless. Fruit a
10-seeded, berry-like stone-fruit.*

170 FOUNDATIONS OF BOTANY

1. G. frondosa, Torr. and Gray. TANGLEBERRY. An erect shrub,
1-3 ft. high ; branches spreading, slender, gray, slightly downy.
Leaves entire, oblong or obovate, obtuse, thin, smooth and green
above, paler, downy, and with resinous dots beneath ; petioles short.
Racemes few-flowered. Corolla small, greenish-pink, short-bell-
shaped; bracts small, oblong, shorter than the pedicels. Berry
depressed-globose, dark blue, with bloom, sweet, about ^ in. in
diameter. On low ground.*

2. G. resinosa, Torr. and Gray. HUCKLEBERRY. A much-
branched, stiff shrub, 1-3 ft. high, slightly downy when young.
Leaves oval or oblong, rarely obovate, obtuse or nearly so, entire,
covered when young with little resinous particles. Flowers in short,
one-sided racemes. Corolla at first conical-ovoid, becoming after-
ward nearly cylindrical, pink or reddish. Fruit (in the typical
form) black, with no bloom, sweet, the seed-like nutlets rather large.
Woods and pastures in sandy soil.

VII. VACCINIUM, L.

Shrubs or small trees. Leaves entire or serrulate, often
leathery and evergreen. Mowers terminal or lateral, clus-
tered or solitary, nodding. Pedicels 2-bracteolate. Calyx-
tube globose or hemispherical, 4-5-lobed, persistent. Corolla
urn-shaped, cylindrical or bell-shaped, 4-5-lobed. Stamens
twice as many as the lobes of the corolla, anthers awned or
awnless. Ovary 4-5-celled, each cell partially divided by a
partition, which makes the ovary appear 8-10-celled ; style
slender ; stigma simple. Fruit a many-seeded berry.*

1. V. corymbosum, L. HIGH-BUSH BLUEBERRY. An erect shrub,
6-12 ft. high ; branches stiff, young twigs minutely warty. Leaves
deciduous, oval to ovate-lanceolate, acute, margins bristly, serrulate,
smooth or downy, short-petioled. Racemes numerous, appearing
with or before the leaves. Bracts oval or oblong, deciduous.
Flowers white or pink. Corolla almost as long as the pedicel,
cylindrical. Berry globose, blue or black, flavor slightly acid, pleas-
ant. Common in woods and thickets, whole plant extremely variable.*

2. V. pennsylvanicum, Lam. DWARF BLUEBERRY, Low BLUE-
BERRY. Low (usually 6-12 in. high, sometimes 2 ft. high) and
smooth, with warty, green branches. Leaves oblong or oblong-
lanceolate, sharply serrate, with little bristle-pointed teeth, both
sides smooth and shining except for down occasionally on the mid-
rib and veins below, pointed at both ends. Flowers few in a clus-
ter, longer than their minute pedicels. Corolla oblong, bell-shaped,

DICOTYLEDONOUS PLANTS 171

a little narrowed at the throat, white or pinkish. Berry blue, with
much bloom, ripening earlier than the other eatable species, sweeter
than No. 1, but not so high-flavored. In dry or sandy soil, espe-
cially N.

3. V. stamineum, L. DEERBERRY, SQUAW HUCKLEBERRY. An
erect shrub, 3—10 ft. high ; branches widely spreading, twigs smooth
or minutely downy. Leaves deciduous, oval or oblong, acute or
taper-pointed at the apex, obtuse or slightly heart-shaped at the
base, firm, smooth, and green above, pale and slightly downy
beneath, petioled. Racemes with leaf-like bracts. Flowers numer-
ous, drooping, on jointed, slender pedicels. Corolla bell-shaped,
purplish-green, 2-awned anthers and style projecting. Berry glo-
bose or pear-shaped, inedible. Dry woods.*

4. V. arboreum, Marsh. FARKLEBERRY. Tree-like, sometimes
30 ft. high ; bark gray ; twigs slender, smooth or downy. Leaves
deciduous, ovate or oval, mucronate, entire or glandular-dentate,
leathery, green above, often slightly downy beneath. Racemes with
leaf-like bracts; pedicels slender, drooping. Corolla campanulate,
white. Anthers included ; style projecting. Berry globose, black,
mealy, ripening in winter. Common in dry, open woods.*

5. V. macrocarpon, Ait. CRANBERRY. Stems creeping, thread-
like, 1-3 ft. or more in length, the branches not quite erect, some-
times 8 in. high. Leaves usually oval or oblong, obtuse, thickish,
evergreen, the younger ones with the margins somewhat rolled
under. Flowers nodding. Petals strongly reflexed, deep rose-red
inside at the base, pale pinkish or almost white at the tips. Sta-
mens with the filaments hardly £ as long as the anthers. Fruit red
or reddish-purple, ellipsoidal or nearly globose, very acid, much
valued for sauce, pies, and jellies. Common in peat-bogs and wet
meadows N.

76. PRIMULACE^. PRIMROSE FAMILY.

Herbs, with simple leaves, often most or all of them radi-
cal. Flowers perfect and regular, generally gamopetalous.
Stamens commonly 5, inserted on the corolla, opposite its
lobes. Pistil consisting of a single stigma and style and a
(generally free) 1-celled ovary, with a free central placenta.

I. DODECATHEON, L.

A smooth, perennial herb, with a cluster of oblong or spatu-
late root-leaves, fibrous roots, and an unbranched scape,

172 FOUNDATIONS OF BOTANY

leafless except for an involucre of small bracts at the summit,
with a large umbel of showy, nodding flowers. Calyx deeply
5-cleft, with reflexed, lanceolate divisions. Tube of the
corolla very short, the divisions of the 5-parted limb strongly
reflexed. Filaments short, somewhat united at the base ;
anthers long, acute, and combining to form a conspicuous cone.

1. D. meadia, L. SHOOTING STAR, INDIAN CHIEF. Corolla
varying from rose-color to white. In rich woods in most of the
Middle and Southern States. Often cultivated.

II. PRIMULA, L.

Low, perennial herbs, with much-veined root-leaves ; scapes,
each bearing an umbel of flowers, which are often showy.
Calyx tubular, decidedly angled, 5-cleft. Corolla more or less
salver-shaped, with the tube widened above .the insertion of
the stamens ; the 5 lobes of the limb often notched or cleft.
Stamens 5, not protruding outside the corolla-tube. Capsule
egg-shaped, splitting at the top into 5 valves, each of which
may divide in halves.

1. P. grandiflora, Lam. TRUE PRIMROSE. Leaves spatulate or
obovate-oblong. Flowers rising on separate slender pedicels from
the leaf-axils. Corolla originally pale yellow, but varying to white,
red, and many intermediate shades, with a broad, flat limb. Culti-
vated from Europe.

2. P. sinensis, Sabine. CHINESE PRIMROSE. A rather coarse,
downy plant. Leaves round-heart-shaped, more or less lobed and
cut, long-petioled. Flowers large, in umbels, usually rose-color or
white. Calyx large, inflated and conical. Cultivated as a house
plant.

III. TRIENTALIS, L.

Low, smooth, perennial herbs, with slender, erect, un-
branched stems. Leaves lanceolate, ovate, or oblong, mostly
in a whorl at the summit of the stem. Flowers one or few,
terminal, on slender peduncles, small, white or pink. Sepals
narrow and spreading. Corolla wheel-shaped, with usually
7 taper-pointed segments. Ovary globose ; style thread-like.
Capsule globose, many-seeded.

DICOTYLEDONOUS PLANTS 173

1. T. americana, Pursh. STAR-FLOWER, CHICKWEED WINTER-
GREEN. Spreading by long and slender rootstocks, branches erect,
stem-like, 3-9 in. high. Leaves very thin, pale green, pointed at both
ends. Flowers white. Capsules white, marked off into polygonal
sections, each corresponding to 1 seed. Cold woods, common N.

IV. STEIRONEMA, Raf.

Perennial herbs. Leaves opposite or whorled, simple,
entire. Flowers yellow, axillary or racemose, on slender
peduncles. Calyx-tube 5-parted, persistent. Corolla 5-parted,
wheel-shaped, tube very short or none, the lobes denticulate
at the apex, and in the bud each one enclosing a stamen.
Stamens 5, distinct or slightly united at the base, sterile rudi-
ments often alternating with them. Ovary globose ; style
slender. Fruit a globose, 5-valved, few or many-seeded
capsule.*

1. S. ciliatum, Raf. FRINGED LOOSESTRIFE. Stems erect, slen-
der, simple, or branched, 1-3 ft. high. Leaves opposite, ovate to
ovate-lanceolate, acute at the apex, rounded at the base, margins and
petioles hairy-fringed; flowers solitary on axillary peduncles, f-1 in.
broad ; petals broadly ovate or roundish, denticulate ; calyx shorter
than the capsule. Woods arid thickets.*

V. LYSIMACHIA, Tourn.

Perennials, with opposite or whorled entire leaves, which
are often dotted. Calyx 5-6-parted. Corolla wheel-shaped,
with its divisions commonly nearly separate. Stamens gen-
erally somewhat monadelphous at the base.

1. L. quadrifolia, L. FOUR-LEAVED LOOSESTRIFE. Stem erect and
simple, 1-2 ft. high, hairy. Leaves whorled, most frequently in
fours, broadly lanceolate. Flowers small, axillary, and solitary, on
long and slender peduncles. Damp or sandy soil.

2. L. stricta, L. BULB-BEARING LOOSESTRIFE. Stems 1-2 ft.
high, finally branching, frequently producing bulblets in the leaf-
axils after flowering. Leaves abundant, generally opposite, narrowly
lanceolate. Flowers small, pediceled, in a long, terminal raceme.
Low or swampy ground.

174 FOUNDATIONS OF BOTANY

VI. ANAGALLIS, Tourn.

Annual or perennial herbs ; stems erect or diffuse. Leaves
opposite or whorled. Flowers axillary, peduncled. Calyx-
tube 5-parted, persistent. Corolla wheel-shaped, 5-parted,
longer than the calyx. Stamens 5, inserted on the base of
the corolla ; filaments bearded. Ovary globose ; style slen-
der ; stigma knobbed. Fruit a many-seeded capsule, the top
coming off like a lid.*

1. A. arvensis, L. POOR MAN'S WEATHER-GLASS, PIMPERNEL.
Annual; stem spreading, widely branched, 4-angled, smooth, 4-12 in.
long. Leaves opposite, sessile, ovate, black-dotted beneath. Flowers
on peduncles longer than the leaves, nodding in fruit, corolla fringed
with glandular hairs, longer than the acute calyx-lobes, bright red,
opening in sunshine. Capsule globose, tipped by the persistent
style. Introduced, and common in fields and gardens.*

77. EBENACEJE. EBONY FAMILY.

Trees or shrubs. Leaves alternate, entire, pinnately veined,
without stipules. Flowers often dioecious. Calyx free from
the ovary, persistent. Stamens 2-4 times as many as the
divisions of the corolla. Ovary 3-12-celled ; ovules 1 or 2 in
each cell. Fruit a berry. Mostly tropical plants.

I. DIOSPYROS, L.

Flowers dioecious or somewhat monoecious, the staminate
ones in cymes, the pistillate ones axillary and solitary.^ Calyx
4-6-lobed. Corolla 4-6-lobed. Stamens in the staminate
flowers usually 16, in the pistillate ones 8, imperfect. Fruit
large, with the persistent calyx attached to its base, 4-8-seeded.

1. D. virginiana, L. PERSIMMON. Trees, with rough, black bark
and very hard wood. Leaves oval or ovate-oblong, acute or acuminate
at the apex, rounded or slightly cordate at the base, entire and dark
green, smooth above, pale and often downy beneath, short-peti-
oled, deciduous; flowers yellowish-white, the parts mostly in 4's ;
fruit globose, edible when ripe, very astringent when green ; seeds
large, compressed, often wanting. Fruit ripening late in the fall.
Common, in old fields and along roadsides S. and S.W.*

DICOTYLEDONOUS PLANTS 175

78. OLEACE^. OLIVE FAMILY.

Shrubs or trees. Leaves opposite, simple or odd-pinnate,
without stipules. Flowers in forking cymes, small, white or
greenish, perfect or imperfect. Calyx free from the ovary,
4-lobed or wanting. Corolla hypogynous, regular, 4-parted or
of 4 separate petals, sometimes wanting. Stamens 2, borne
on the petals or hypogynous. Ovary 2-celled. Fruit 1-2-
celled, each cell 1 -seeded, rarely 2-seeded.

I. FRAXINUS, Tourn.

Deciduous trees. Flowers dioecious. Petals wanting (in
our species). Stamens 2, hypogynous. Fruit a 1-2-celled
key, each cell 1-seeded.

1. F. americana, L. WHITE ASH. A large tree; bark rough,
gray ; wood hard, strong, elastic ; twigs and petioles smooth. Leaflets
usually 7, ovate to ovate-lanceolate, taper-pointed at the apex, rounded
or obtuse at the base, entire or slightly serrate, smooth above, often
downy beneath, short-stalked. Flowers mostly dioecious. Calyx of
the pistillate flowers persistent. Key l|—2 in. long, winged only
at the apex ; wing spatulate or oblanceolate. In rich woods and
swamps.*

2. F. pubescens, Lam. RED ASH. A small tree; bark rough,
dark gray ; twigs and petioles densely velvety-downy. Leaflets 5-9,
oblong-ovate to ovate-lanceolate, taper-pointed at the apex, narrowed
into a short stalk at the base, finely serrate, smooth above, velvety-
downy beneath. Calyx of the pistillate flowers persistent. Key 1|-
2 in. long, the wing somewhat extended along the sides, oblanceolate
or spatulate, often notched. Swarnps and moist soil.*

3. F. platycarpa, Michx. WATER ASH. A small tree ; wood
soft, light and weak ; twigs smooth or downy. Leaflets 5-7, ovate
or elliptical, acute at the apex, acute or obtuse at the base, entire or
slightly serrate, smooth or slightly downy, stalked. Flowers dioe-
cious. Calyx persistent. Key often 3-angled or 3-winged, wings
running nearly to the base, oblong or oval, pinnately veined. In
swamps and wet soil.*

4. F. quadrangulata, Michx. BLUE ASH. A large tree, with wood
heavy, but not as tough as No. 1 ; the most vigorous twigs usually
square. Leaflets 7-9, with short stalks, somewhat ovate or lanceolate,
acute, sharply serrate. Fruit winged to the base, of nearly the same
width throughout, narrowly oblong. Rich woods, especially W.

176 FOUNDATIONS OF BOTANY

II. FORSYTHIA, Vahl.

Shrubs. Leaves opposite or in threes, appearing later than
the flowers, serrate. Calyx very short, deciduous. Corolla
yellow, bell-shaped, its lobes long and slender. Stamens
inserted on the base of the corolla-tube. Pod 2-celled, many-
seeded.

1. F. viridissima, Lindl. A hardy shrub, with branches erect or
nearly so. Leaves all simple, lance-oblong. Calyx-lobes half as long
as the tube of the corolla. Lobes of the corolla spreading, narrow-
oblong, style equal in length to the tube of the corolla. Cultivated
from Asia.

2. F. suspensa, Vahl. A hardy shrub, with drooping branches.
Leaves broadly ovate, often some of them with 3 leaflets, the lateral
leaflets small. Lobes of the corolla longer, broader, and more spread-
ing than in No. 1. Style shorter than the tube of the corolla. Culti-
vated from Asia, less common than No. 1, often trained over porches
and arbors.

HI. SYRINGA, L.

Tall shrubs, forking frequently, from the failure of the
terminal buds on most branches. Leaves simple, entire.
Flowers in close, compound panicles. Calyx 4-toothed.
Corolla salver-shaped, the tube long, the limb 4-lobed. Pod
dry, flattened at right angles to the partition, 4-seeded.

1. S. vulgaris, L. COMMON LILAC. A strong-growing, hardy bush.
Leaves ovate, somewhat heart-shaped. Flowers sweet-scented, in
very close, large clusters, lilac or white. Corolla-lobes concave.
Very commonly cultivated from Eastern Europe.

2. S. persica, L. PERSIAN LILAC. A more slender and less
branched shrub than No. 1. Leaves lance-ovate, somewhat nar-
rowed or tapering at the base. Flowers in rather loose clusters, not
very sweet-scented, pale lilac or white. Corolla-lobes ovate, some-
what bent inward. Pods linear. Cultivated from Western Asia,
less common than No. 1.

IV. CHIONANTHUS, L.

Shrubs or small trees. Leaves simple, opposite, entire,
petioled, deciduous. Flowers in panicles borne on wood of
the previous season. Calyx small, 4-cleft, persistent. Corolla

DICOTYLEDONOUS PLANTS 177

wheel-shaped, 4-parted, the lobes long and linear. Stamens
2-4, included, inserted on the base of the corolla. Style
short ; stigma 2-lobed. Fruit a 1-seeded stone-fruit.*

1. C. virginica, L. FRINGE-TREE. A small tree, with smooth, light
gray bark and spreading branches. Leaves oval to oblong, acute or
obtuse at each end, smooth or slightly downy. Panicles large and
loose, leafy-bracted, appearing with the leaves. Flowers on slender,
drooping pedicels. Petals 1 in. or more in length. Fruit ovoid, pur-
ple, J~f in. long. Along streams, usually on light soil.*

V. LIGUSTRUM, Tourn.

Shrnbs. Leaves simple, opposite, entire, deciduous or some-
times persistent. * Flowers in terminal panicles or similar
clusters, white, small. Calyx minutely 4-toothed or truncate.
Corolla funnel-form, 4-lobed. Stamens 2, short, inserted in the
tube of the corolla. Ovary free, 2-celled, 2 ovules in each
cell, style short. Fruit a 1-4-seeded, globose berry.*

1. L. vulgare, L. PRIVET. A branching shrub, 4-10 ft. high;
branches long and slender. Leaves somewhat leathery, lanceolate to
obovate, short-petioled, tardily deciduous. Panicles dense, minutely
downy. Flowers £ in. wide, fragrant. Stamens included. Berries
black. Introduced from Europe and used largely for hedges.*

79. GENTIAN ACE^. GENTIAN FAMILY.

Annual or perennial herbs. Leaves entire, usually oppo-
site, sometimes alternate, without stipules. Flowers regular,
solitary or in cymes. Calyx free from the ovary, 4-8-toothed
or lobed. Corolla hypogynous, wheel-, bell-, or funnel-shaped,
4-8-lobed. Stamens 4—8, inserted on the corolla-tube ; fila-
ments thread-shaped; anthers facing inwards. Ovary 1-2-
celled ; ovules many, on 2 opposite placentas. Capsule 1-celled
or partially 2-celled, 2-valved, many-seeded.

I. OBOLARIA, L.

A low, smooth, purplish-green perennial. Flowers axillary
and terminal, Calyx of 2 distinct, spatulate, bract-like sepals.

178 FOUNDATIONS OF BOTANY

Corolla tubular-bell-shaped, 4-lobed. Stamens short, inserted
at the notches of the corolla. Style short ; stigma 2-lipped.
Capsule ovoid, more or less 2-4-celled ; seeds very minute
and numerous.

1. 0. virginica, L. PENNYWORT. Stem 3-8 in. high, often several
from the same root. Leaves somewhat fleshy, wedge-obovate or
somewhat diamond-shaped, often truncate, sessile. Flowers oppo-
site or terminal in threes, nearly sessile. Corolla pale purple or
nearly white. Rich woodlands, among dead leaves.

H. MENYANTHES, Tourn.

Perennial, scape-bearing marsh herbs. Rootstock creeping.
Leaves of 3 leaflets. Flowers racemed. Calyx 5-parted.
Corolla fleshy, funnel-shaped, the limb 5-parted. Stamens 5,
inserted on the corolla-tube. Disk of 5 hypogynous glands.
Ovary 1-celled ; style thread-shaped ; stigma 2-lobed. Capsule
globose, many-seeded.

1. M. trifoliata, L. BUCK-BEAN, MARSH TREFOIL. Rootstocks
stout and matted. Leaflets obtuse, entire. Flowers f in. in diam-
eter, white or pinkish. Bogs, especially IS".

80. APOCYNACE^. DOGBANE FAMILY.

Trees, shrubs, or herbs, with milky juice, often climbing.
Leaves usually opposite, rarely whoiied; entire, nearly or
quite without stipules. Flowers regular, solitary, or in cymes.
Calyx 4-5-cleft. Corolla hypogynous, funnel-, salver-, or bell-
shaped, sometimes with scales in the throat. Stamens, 4-5,
borne on the corolla-tube or throat; filaments very short;
anthers somewhat attached to the stigma. Ovary of 2 car-
pels, free or somewhat united ; style short ; stigma entire
or 2-cleft. Fruit of 2 many-seeded pods (in the genera here
described).

I. AMSONIA, Walt.

Perennial herbs ; stem erect, branched. Leaves alternate.
Flowers in terminal panicles. Calyx small, 5-parted. Corolla

DICOTYLEDONOUS PLANTS 179

small, pale blue, funnel or salver form, downy within. Sta-
mens inserted above the middle of the tube, included. Ovary
of 2 carpels, united at the top by the slender style; stigrna
globose, surrounded by a cup-shaped appendage. Fruit 2
slender, erect, many-seeded follicles ; seeds without tufts of
hairs.*

1. A. tabernsemontana, Walt. AMSONIA. Stem smooth and gla-
brous, branched above, 2-3 ft. high. Leaves lanceolate, entire,
acuminate at the apex, acute at the base, smooth above, with a
bloom or slightly downy beneath, short-petioled. Flowers numer-
ous, on bracted pedicels. Corolla-tube slender, smooth or sometimes
downy above, the lobes narrow, as long as the tube. Follicles
slender, spreading, 4-6 in. long; seeds downy. Swamps and wet
ground S.*

II. VINCA, L.

Perennial herbs or small, slender shrubs ; juice not percep-
tibly milky. Leaves evergreen. Flowers solitary, white,
blue, or purple. Calyx 5-parted, lobes taper-pointed, glandu-
lar inside at the base. Corolla salver-shaped, thickened at
the throat, 5-lobed. Stamens 5, inserted on the upper or
middle part of the corolla-tube. Ovary of 2 carpels. Pods
2, slender, cylindrical, many-seeded.

1. V. minor, L. PERIWINKLE. Stem slender, trailing, often root-
ing at the nodes, 1-3 ft. long. Leaves ovate, acute at the apex,
short-petioled, bright green. Flowers axillary, solitary, 1 in. wide.
Calyx with linear lobes nearly as long as the inflated tube of the
blue corolla. Matured pods slender, slightly divergent. Introduced
from Europe and common in gardens.*

m. APOCYNUM, Tourn.

Perennial herbs ; stems with very tough bark, branched
above. Leaves opposite, entire. Flowers in terminal and
axillary bracted cymes. Calyx small, 5-parted, lobes acute.
Corolla bell-shaped, 5-lobed, with a small, scale-like append-
age at the base of each lobe. Stamens 5, distinct, inserted
on the base of the corolla-tube. Ovaries 2, distinct, united
by the styles ; stigma obtuse, 2-lobed. Pods long, slender,
many-seeded ; seeds with a tuft of hairs.*

180 FOUNDATIONS 0$ BOTANY

1. A. cannabinum, L. INDIAN HEMP. Stem erect, smooth, with
numerous erect or ascending branches. Leaves oval to oblong,
miicronate at the apex, rounded at the base, downy beneath, short-
petioled. Cymes terminal, compact, shorter than the leaves. Flowers
are on short, bracted pedicels, greenish-white, about | in. broad.
Calyx-lobes lanceolate, nearly as long as the tube of the corolla.
Corolla-lobes erect. Pods very slender, tapering, 3-4 in. long.
Along fences and in thickets.*

2. A. androsaemifolium, L. DOGBANE. Plant 2-3 ft. high,
usually smooth, purplish, the branches spreading and forking.
Leaves 2-3 in. long, acute, mucronate, petioles about £ in. long.
Cymes mostly terminal, few-flowered. Calyx-teeth lance-ovate,
about half as long as the corolla-tube. Corolla pale red or whitish,
its lobes recurved. Pods stouter than in No. 1. Roadsides and
clearings, common.

IV. NERIUM, L.

Shrubs. Leaves mostly whorled in threes. Flowers in termi-
nal cymes. Calyx small, lobes acute. Corolla salver-form,
the throat of the tube crowned with cleft or cut-fringed
scales. Stamens 5, short, included ; anthers tipped with a
hairy bristle. Ovary of 2 carpels ; style short. Pods erect,
seeds with a tuft of hairs.*

1. N. Oleander, L. OLEANDER. Stem erect, diffusely branched
from below, 4-10 ft. high. Leaves narrowly elliptical, acute at each
end, thick and leathery, short-petioled. Flowers showy, in large
clusters, red or white, often double ; scales of the crown 3-4-pointed
unequal teeth ; pods spindle-shaped, 3-4 in. long. Introduced from
Palestine, common in cultivation.*

81. ASCLEPIADACEJE. MILKWEED FAMILY.

Shrubs or herbs, often twining ; juice usually milky.
Leaves generally opposite or whorled, entire, without stipules.
Flowers regular. Calyx 5-parted. Corolla 5-parted. Sta-
mens 5 ; the filaments usually cohering around the styles,
often with hood-like appendages, each with an incurved horn
borne on the stamen-tube and forming a crown around the
stigma (Fig. 20, A) ; anthers pressing against the lobes of the
stigma ; the pollen clinging together in tough, waxy or fine-

DICOTYLEDONOUS PLANTS 181

grained masses. Ovary free from the calyx-tube, of 2 carpels,
more or less united below but unconnected above ; styles 2 ;
stigmas 5-angled ; ovules several-many. Fruit consisting of
1 or 2 pods. The flowers are very highly specialized for
pollination by insects (see below, under Asclepias).

I. ASCLEPIAS, L.

Perennial herbs. Flowers in simple (usually many-flow-
ered) umbels. Calyx small, 5-parted, its lobes reflexed.
Corolla deeply 5-parted, with reflexed lobes ; crown of hoods
and horns conspicuous (Fig. 20, A, B). Stamens with their
filaments united into a tube around the pistil and anthers
adnate to the stigma (Fig. 20, D, E) ; anther-cells 2, each cell
containing an elongated, pear-shaped, tough mass of pollen, a
mass from one anther always paired with one from the adjoin-
ing anther and each two together suspended from one of the
5 split glands on the angles of the stigma (Fig. 20, D, E).
Ovaries 2 ; styles very short. Pods 2 or sometimes 1 and the
other undeveloped. Seeds flat, each with a tuft of long, silky
hairs. The flowers are pollinated by insects, which get their
feet entangled in the clefts of the glands (Fig. 20, g) and
then carry off the pollen-masses. (See Mtiller, The Fertiliza-
tion of Flowers, pp. 396-399 inclusive.)

1. A. purpurascens, L. PURPLE MILKWEED. Stem 1-3 ft. high,
somewhat branched above. Leaves 4-6 in. long, elliptical or nearly
so, the upper ones taper-pointed, slightly velvety beneath, short-
petioled. Umbels terminal. Flowers % in. long, dark purple ; pedi-
cels shorter than the peduncle ; horn broadly scythe-shaped, with
the point bent sharply inward. Dry soil.

2. A. Cornuti, Decaisne. COMMON MILKWEED. Stem stout,
3-4 ft. high, finely downy. Leaves 4-8 in. long, oblong or nearly
so, downy beneath. Umbels terminal or nearly so. Flowers vary-
ing from purple or greenish-purple to whitish, numerous, with a
strong, sweet, but sickening odor. Hoods with a tooth on each side
of the stout horn. Common in rich soil.

3. A. phytolaccoides, Pursh. POKE-LEAVED MILKWEED. Stem
rather slender, 3-5 ft. high. Leaves 6-9 in. long, ovate or oval-
lanceolate, taper-pointed, short-petioled. Umbels several, mostly
lateral; pedicels slender and drooping. Lobes of the corolla

182

FOUNDATIONS OF BOTANY

greenish ; hoods white, with 2 teeth ; horns with an awl-shaped
point extending far out of the hoods. Damp thickets N. and E.

4. A. variegata, L. WHITE MILKWEED. Stem stout, leafless
and smooth below, leafy and downy in lines above. Leaves oppo-
site, the middle ones sometimes in fours, petioled, ovate to obovate,

FIG. 20. — Flower of Asclepias Cornuti.

A, entire flower ; B, vertical section ; C, diagram ; D, details of pollen-masses
and glands, ca, calyx ; c, corolla ; hd, hood ; hn, horn ; a, anther ; s, stig-
ma ; o, ovary ; g, gland ; p, pollen-mass. (All considerably enlarged.)

cuspidate, smooth on both sides, pale beneath, edges slightly crenate.
Umbels 1-5, compact, downy, 1-2 in. long ; pedicels erect, as long
as the peduncles. Corolla white, often purple at the base ; hoods
roundish, spreading, a little longer than the thick, awl-pointed,
incurved horn. Dry, open woods E. and S.*

5. A. quadrifolia, L. FOUR-LEAVED MILKWEED. Stem slender,
1^-2 ft. or more high, usually leafless below. Leaves in 1 or 2

DICOTYLEDONOUS PLANTS 183

whorls of 4 each, near the middle of the stem, and a pair or two
opposite, thin, slender-petioled, 2-4 in. long, ovate-lanceolate, taper-
pointed. Umbels usually 2, sometimes 1, with slender pedicels.
Corolla-lobes very pale pink or whitish ; hoods white ; horn short,
stout, and bent inward. Dry woods and fence-rows.

II. HOYA, R. Br.

Shrubby, more or less climbing, smooth, tropical plants.
Leaves fleshy. Calyx 5-cleft, corolla 5-lobed, wheel-shaped,
its divisions thick and with a waxy look. Crown of 5 spread-
ing segments. Pollen-masses fastened by the bases.

1. H. carnosa, R. Br. WAX PLANT. Stems long and slender,
rooting and trailing. Leaves oval or nearly so, thick, dark green.
Flowers in close umbels, pink or whitish, the corolla-lobes covered
on the upper surface with minute projections. Cultivated from
India as a house plant and in conservatories.

82. CONVOLVULACE^. MORNING-GLORY FAMILY.

Usually twining herbs or shrubs, often with milky juice.
Leaves alternate (wanting in Cuscuta), without stipules.
Flowers variously clustered, rarely solitary, often large and
showy. Sepals 5. Corolla hypogynous, regular, tubular, bell-
shaped or funnel-shaped ; its limb more or less 5-lobed or
angled. Stamens 5, inserted on the corolla-tube. Ovary
usually 2-4-celled ; style slender, 2-4-cleft ; ovules 1 or 2 in
each cell. Capsule 1-4-celled, 2-4-valved or bursting open
across the base.

I. CALYSTEGIA, R. Br.

Twining, trailing, or nearly erect perennials. Leaves heart-
shaped or arrow-shaped. Flowers peduncled, axillary and
solitary. Calyx enclosed in 2 large, leaf-like, usually heart-
shaped bracts ; sepals equal. Corolla bell-funnel-shaped, its
border nearly or quite entire ; style 1 ; stigmas 2. Pod 1-celled
or partially 2-celled, 4-seeded.

1. C. sepium, R. Br. CREEPERS, RUTLAND BEAUTY. Stem
twining or sometimes extensively trailing. Leaves heart-arrow-

184 FOUNDATIONS OF BOTANY

shaped or somewhat halberd-shaped, the lobes at the base trun-
cate. Flowers numerous and showy, white or tinged with rose-color.
Thickets and banks of streams, often cultivated.

2. C. spithamaea, Pursh. Downy, stem 6-12 in. high, erect or
reclining. Leaves oblong, sometimes heart-shaped or eared at the
base. Flowers white. In sandy soil.

II. CONVOLVULUS, L.

Herbs or shrubs, with stems twining or nearly erect. Calyx
not bracted. Corolla broadly funnel-form or bell-shaped.
Stamens not projecting from the corolla. Style 1 ; stigmas 2,
thread-like ; ovary and pod 2-celled, 4-seeded.

1. C. arvensis, L. BINDWEED. A perennial, prostrate or climb-
ing herb, with many stems, from a long, slender rootstock. Leaves
very variable, more or less arrow-shaped, 1-3 in. long. Peduncles
mostly 1-flowered ; flowers white or pinkish, about f in. long. A
weed in fields E. ; introduced from Europe.

HI. QUAMOCLIT, Tourn.

Twining annual herbs. Sepals 5, mostly mucronate or
bristle-pointed. Corolla tubular, with a narrow, spreading
border. Stamens projecting. Style 1 ; stigma knobbed,
2-lobed. Pod 4-celled, the cells 1-seeded.

1. Q. vulgaris, Choisy. CYPRESS VINE. Stem slender, smooth,
twining high. • Leaves dark green, pinnately cut, the divisions lin-
ear, smooth. Peduncles slender, as long as the leaves, 1-5-flowered ;
pedicels thickened upward. Sepals ovate or oblong, mucronate.
Corolla bright scarlet, or sometimes yellowish-white, salver-form, the
tube 1-1 ^ in. long, the limb flat and spreading, £-| in. wide. Cap-
sule ovoid, twice the length of the sepals. Common in gardens.*

IV. IMPOMCEA, L.

Annuals or perennials ; steins often twining. Flowers
showy. Calyx not bracted at the base, of 5 sepals. Corolla
bell-shaped or funnel-shaped, twisted in the bud. Stamens
not projecting from the corolla. Style slender ; stigma
knobbed, 2-lobed. Fruit a 2-3-celled capsule. [/. purpurea,
the common morning-glory, blossoms too late for school study.
/. Batatas, the sweet potato, seldom flowers.]

DICOTYLEDONOUS PLANTS 185

1. I. hederacea, Jacq. WILD MORNING-GLORY. Stems hairy,
twining. Leaves heart-shaped, 3-lobed. Peduncles 1-3-flowered.
Calyx very hairy below. Corolla showy, bluish-purple or white,
Pod usually 3-celled, with .2 seeds in each cell. A weed in fields
and about dwellings ; introduced from tropical America.

2. I. pandurata, Meyer. WILD POTATO VINE. Perennial, from
a very large, tuberous root ; stem trailing or twining, smooth or
slightly downy, 5-10 ft. long. Leaves broadly heart-shaped, with
the apex slender and obtuse, sometimes fiddle-shaped or 3-lobed ;
petioles slender. Peduncles longer than the petioles, 1-5-flowered.
Sepals oblong, obtuse, smooth, mucronate, the 2 outer ones shorter.
Corolla white with a purple throat, 2—3 in. wide, lobes pointed.
Capsule globose, 2-3-seeded, the seeds woolly 011 the angles. On
dry or damp, sandy soil, along fences, railroad embankments, etc.,
common S. and W.*

83. POLEMONIACEJE. PHLOX FAMILY.

Annual or perennial herbs, rarely shrubs. Leaves alter-
nate or the lower opposite, without stipules. Flowers in ter-
minal, forking cymes. Calyx free from the ovary, 5-lobed.
Corolla regular or nearly so, 5-parted. Stamens 5, inserted
on the corolla-tube, usually unequal. Ovary 3-celled ; style
simple ; stigmas 3, linear ; capsule 3-celled, the cells 1-many-
seeded.

I. PHLOX, L.

Perennial or rarely annual herbs ; stems erect or diffuse.
Leaves opposite, or the upper alternate, entire, without stip-
ules. Flowers showy, white or purple, in terminal cymes
or panicles. Calyx cylindrical or funnel-form, 5-cleft, the
lobes acute. Corolla salver-form, the tube long and slender,
the limb 5-parted, the lobes spreading, entire or obcordate.
Stamens included, unequal. Ovary 3-celled, style slender.
Capsule ovoid, 3-celled, 1— few-seeded ; seeds wingless or
narrow-winged.*

1. P. paniculata, L. GARDEN PHLOX. Perennial ; stems in
clumps, stout, erect, simple or branched above, 2-4 ft. high. Leaves
ovate-lanceolate to oblong, taper-pointed at the apex, rounded or
cordate at the base, thin, smooth, veins prominent beneath. Cymes
numerous and compact, forming a pyramidal panicle ; pedicels short.

186 FOUNDATIONS OF BOTANY

Calyx-teeth long, bristle-pointed. Corolla purple to white, lobes
round-obovate, shorter than the tube. Capsule longer than the
calyx-tube. In rich woods ; often cultivated.*

2. P. maculata, L. WILD SWEET WILLIAM. Stem erect, smooth
or nearly so, rather slender, purple-spotted, 1-2 ft. high. Lower
leaves lanceolate, the upper ones broader, taper-pointed, roundish
or heart-shaped at the base. Panicle many-flowered, narrow, ellip-
soidal. Calyx-teeth lanceolate, hardly acute. Flowers purple, occa-
sionally white. Damp woods and fields.

3. P. pilosa, L. DOWNY PHLOX. Perennial; stem erect, slen-
der, simple or branched, 1-2 ft. high. Leaves linear-lanceolate to
linear, distant, spreading, long, taper-pointed, sessile ; stern and
leaves downy. Cymes corymbose, loose. Flowers short-pediceled.
Calyx glandular-viscid, the teeth shorter than the tube of the purple
corolla, bristle-pointed. Corolla-tube downy, lobes obovate. Capsule
twice the length of the calyx-tube. In dry, open woods.*

4. P. divaricata, L. WILD BLUE PHLOX. Perennial; stems
erect or ascending from a decumbent base, sticky-downy, 1 ft. high.
Leaves distant, lanceolate to oblong, acute at the apex, rounded at
the base, sessile, downy. Cymes corymbed, loosely flowered. Calyx-
teeth awl-shaped, longer than the tube. Corolla bluish-purple, |~|
in. long, lobes notched at the apex, as long as the tube. Capsule
oval, shorter than the calyx-teeth. In moist, open woods.*

5. P. Drummondii, Hook. DRUMMOND'S PHLOX. Annual; stem
erect or ascending, slender, weak, branching, glandular-downy, 6-12
in. high. Leaves mostly alternate, lanceolate to oblong, downy, the
upper clasping by a heart-shaped base. Corymbs loose. Flowers
rather long-pediceled. Calyx-tube short, the teeth lanceolate, bristle-
pointed, soon recurved. Corolla purple to crimson or white, orifice
of the tube usually with a white or yellowish star-like ring, lobes
rounded at the apex. Ovary 3-seeded, angles of the seeds winged.
Introduced from Texas and common everywhere in gardens.*

6. P. subulata, L. GROUND PINK, Moss PINK, FLOWERING Moss.
Stems perennial, prostrate, 8-18 in. long, with many short, somewhat
upright branches, 2-4 in. high. Leaves linear-awl-shaped, stiff,
about \ in. long, crowded, with clusters of smaller ones in their
axils. Flower-clusters 3-6-flowered. Corolla pink-purple, with a
darker center, or sometimes white. Forms dense mats on rocky or
sandy hillsides. S. and W. and often cultivated.

II. POLEMONIUM, L.

Perennial herbs. Leaves alternate, pinnate. Flowers cor-
ymbed. Calyx bell-shaped, 5-lobed. Corolla wheel-shaped,
the limb with 5 obovate lobes. Stamens borne on the throat of

DICOTYLEDONOUS PLANTS 187

the corolla, the filaments enlarged and hairy below. Capsule
ovoid, 3-celled, many-seeded.

1. P. reptans, L. JACOB'S LADDER, BLUE VALERIAN, BLUE-
BELL. Stems smooth, branched, and leaning over, 6-12 in. high.
Leaflets usually 7 or 9, about an inch long. Corolla blue, about
3 times as long as the calyx. Capsule 3-seeded, borne on a short
stalk in the persistent calyx. Damp, open woods, sometimes culti-
vated.

84. HYDROPHYLLACEJE. WATERLEAF FAMILY.

Herbs, usually hairy. Leaves commonly alternate and
alternate-lobed. Flowers with their parts in fives, in appear-
ance not unlike those of the following family, in one-sided
cymes, which are coiled up at first. Calyx free from the
ovary, usually with appendages at the notches. Corolla often
with scales or nectar-bearing folds inside. Stamens borne by
the corolla-tube. Style 2-cleft, or styles 2. Ovary entire and
usually 1-celled. Fruit a capsule, 2-valved, 4-many-seeded.

I. HYDROPHYLLUM, Tourn.

Coarse perennials. Leaves large, petioled. Flowers white
or pale blue, inconspicuous. Calyx 5-parted, sometimes ap-
pendaged at the notches. Corolla bell-shaped, 5-cleft, with
5 double, nectar-bearing folds inside. Stamens projecting, the
filaments bearded. Style projecting; ovary covered with
bristly hairs, the placentae very broad and fleshy, enclosing
the ovules. Capsule globular, 1-4-seeded.

1. H. macrophyllum, Nutt. A coarse, rough-hairy plant, about
1 ft. high, from scaly-toothed rootstocks. Leaves oblong, pinnate and
pinnately cut, the divisions mucronate, obtuse, coarsely toothed.
Flower-cluster dense, globular, long-peduncled. Flowers about £ in.
long. Calyx little or not at all appendaged, its lobes broad at the
base, but with slender, tapering points. Corolla white. Rich, rocky
woods W. and S.

2. H. virginicum, L. Nearly smooth, 1-2 ft. high, stem often fork-
ing at the base. Leaves of the stem mostly near the top, pinnately
cut into 5-7 divisions ; lobes oval-lanceolate, deeply serrate, the lowest

188 FOUNDATIONS OF BOTANY

ones distinct ; petioles of the radical and lower leaves 4-8 in. long.
Flower-clusters on peduncles longer than the petioles of the upper
leaves, from the axils of which or opposite which they arise. Flowers
about \ in. long. Calyx not appendaged, its lobes narrowly linear,
bristly-margined. Corolla whitish, with purplish veins. Moist
woods.

3. H. appendiculatum, Michx. Hairy, 1-1^ ft. high. Stem-leaves
palmately 5-lobed, the lobes acute, toothed, lowest ones pinnately
divided. Flower-cluster rather loose. Calyx appendaged at the
notches. Corolla blue. Stamens projecting from the corolla little
or not at all. Moist woods.

H. PHACELIA, L.

Herbs, mostly annual. Leaves alternate, sometimes simple,
but in most species lobed or divided. Flowers in one-sided
clusters, often showy. Calyx 5-parted, without appendages.
Corolla with 5 spreading lobes. Ovary 1-celled, with narrow
placentae.

1. P. tanacetifolia, Benth. A tall, hairy annual. Leaves pin-
nately cut. Spikes long, densely flowered. Flowers showy, blue.
Stamens projecting. Capsule 4-seeded. Cultivated from California.

2. P. Whitlavia, Gray. WHITLAVIA. A rather coarse, sticky
annual. Leaves broad, ovate, coarsely toothed, petioled. Flower-
clusters a loose raceme. Flowers showy, about 1 in. long, blue or
sometimes white. Corolla bell-shaped. Stamens and style project-
ing. Capsule many-seeded. Cultivated from California.

3. P. Menziesii, Torr. EUTOCA. A much-branched, somewhat
rough or rough-hairy plant, 3-12 in. high. Leaves linear, or lanceo-
late, entire or nearly so. Flowers showy, violet or white, loosely
panicled. Capsule many-seeded. Cultivated from California.

85. BORR AGIN ACE JE. BORAGE FAMILY.

Mostly herbs, with steins and foliage roughened with stiff
hairs. Leaves alternate and entire, not aromatic. Flowers
generally in a coiled inflorescence. Calyx 5-parted. Corolla
hypogynous, generally 5-lobed and regular. Stamens 5,
inserted on .the corolla-tube. Style 1; ovary commonly
4-lobed, ripening into 4 l-seedM nutlets,

DICOTYLEDONOUS PLANTS 189

I. HELIOTROPIUM, Tourn.

Herbs or low shrubs. Leaves petioled. Flowers white,
blue, or lilac, in one-sided, curved spikes. Calyx 5-parted.
Corolla salver-shaped, the throat open. Anthers almost ses-
sile. Style short ; stigma conical or knobbed. Fruit sepa-
rating into 2 or 4 nutlets.

1. H. peruvianum, L. COMMON HELIOTROPE. Somewhat shrubby,
much branched. Leaves lance-ovate or somewhat oblong, veined
and much wrinkled, short-petioled. Flowers numerous, in a cluster
of terminal spikes, bluish-purple or lavender, very sweet-scented, the
odor not unlike that of vanilla. Cultivated from Peru.

II. CYNOGLOSSUM, Tourn.

Coarse, rough-hairy or silky biennials. Flowers small,
bluish-purple or white, in forked and usually bractless cymes.
Calyx 5-parted. Corolla funnel-shaped, the mouth closed by
prominent scales, its lobes obtuse. Stamens not projecting.
Styles stiff, persistent. Nutlets 4, covered with hooked or
barbed bristles, attached to a thickened, conical receptacle.

1. C. officinale, L. HOUND'S-TONGUE, SHEEP-LICE, DOG-BUR,
STICK-TIGHTS. Stem 1-2 ft. high, soft-downy, panicled above.
Root-leaves 8-10 in. long, long-petioled, oblong or oblong-lanceo-
late; stem-leaves sessile, linear-oblong or lanceolate, rounded or
heart-shaped at the base. Corolla £ in. in diameter, reddish-purple.
Nutlets % in- l°ng> with a thickened border. Whole plant with a
strong smell like that of mice. A troublesome weed, along roadsides
and in pastures, introduced from Europe.

2. C. virginicum, L. WILD COMFREY. Perennial. Stem stout,
simple, erect, leafless above, 2-3 ft. high. Leaves oval or oblong,
the upper clasping by a heart-shaped base. Racemes bractless.
Flowers pale blue, on" short pedicels, which are recurved in fruit.
Nutlets not margined, separating and falling away at maturity. On
dry soil.

III. ECHINOSPERMUM, Lehm.

Annual or biennial herbs, grayish, with rough hairs.
Flowers small, blue or whitish, racemed or spiked. Corolla
salver-shaped, its throat closed with 5 concave scales. Nutlets

190 FOUNDATIONS OF BOTANY

more or less covered with prickles, which are barbed at the
tip, attached by their sides to the base of the style.

1. E. virginicum, Lehm. BEGGAR'S LICE. A coarse biennial,
2-4 ft. high, the stem much branched above. Root-leaves roundish-
ovate or heart-shaped, on slender petioles ; stem-leaves 3-4 in. long,
pointed at both ends. Racemes 1-3 in. long, terminating the slender,
spreading branches. Flowers small, bluish-white. Fruit forming a
troublesome bur. Fence-rows and thickets.

IV. MERTENSIA, Roth.

Perennial herbs. Leaves generally pale, smooth, and entire.
Calyx short, deeply 5-cleft or 5-parted. Corolla somewhat
trumpet-shaped or funnel-shaped, often with 5 small folds or
ridges in the throat, between the points of insertion of the
stamens. Style long and slender. Nutlets smooth, or at
length becoming wrinkled.

' 1. M. virginica, DC. LUNGWORT, BLUEBELLS. Smooth, nearly
erect, 1-11 ft. high. Root-leaves large, obovate, or nearly so, and
petioled; stem-leaves smaller, sessile. Flowers clustered. Corolla
nearly trumpet-shaped, varying with age from lilac to blue (or occa-
sionally white). Stamens with slender filaments projecting beyond
the corolla-tube. Damp, open woods and banks of streams, some-
times cultivated.

V. MYOSOTIS, Dill.

Low, annual, biennial, or perennial herbs ; stems branching,
erect or diffuse. Leaves alternate, entire. Flowers small,
blue, pink, or white, in elongated, bractless racemes. Calyx
5-cleft, the lobes erect or spreading in fruit. Corolla salver-
forni, 5-lobed, the tube as long as the calyx, the throat with
5 small appendages. Stamens 5, inserted in the tube of the
corolla, included. Ovary 4-parted; style slender. Nutlets
smooth or downy, elliptical, compressed.*

1. M. palustris, Withering. FORGET-ME-NOT. Perennial, from
slender rootstocks. Stems slender, downy, rooting at the nodes,
6-15 in. long ; leaves oblong to oblong-lanceolate, obtuse, narrowed
to the sessile base, appressed-downy. Racemes many-flowered ; pedi-
cels becoming elongated in fruit. Lobes of the calyx shorter than
the tube, spreading in fruit. Corolla blue with a yellow eye ; nut-
lets angled, smooth. Common in gardens and often naturalized.*

DICOTYLEDONOUS PLANTS 191

2. M. laxa, Lehm. SMALL FORGET-ME-NOT. Annual or peren-
nial ; whole plant downy ; stem slender, weak, decumbent and root-
ing at the base, 1-2 ft. long. Lower leaves spatulate, the upper
lanceolate. Racemes loosely flowered, becoming elongated in fruit.
Pedicels spreading. Calyx rough-hairy, the lobes as long as the
tube. Corolla pale blue, with a yellow eye. Nutlets -convex on all
sides. On low ground and in brooks and ponds.*

VI. LITHOSPERMUM, Tourn.

Herbs, with stout, usually reddish roots. Flowers appear-
ing axillary and solitary or else in leafy-bracted spikes.
Corolla funnel-shaped or salver-shaped, with or without folds
or appendages at the mouth of the tube ; the limb 5-cleft, its
divisions rounded. Stamens included in the corolla-tube, the
anthers nearly sessile. Nutlets either smooth or wrinkled,
generally very hard and bony.

1. L. arvense, L. CORN GROMWELL. A rough weed, about 1 ft.
high. Leaves narrowly lanceolate. Flowers inconspicuous, whitish
in the upper leaf axils. Corolla hardly extending beyond the calyx,
without appendages in the throat. Nutlets rough or wrinkled and
dull. Sandy banks and roadsides ; introduced from Europe.

2. L. hirtum, Lehm. HAIRY PUCCOON. Rough-hairy, perennial,
1-2 ft. high. Corolla deep orange-yellow, with appendages in the
throat and clad with wool within at the bottom ; flowers handsome,
peduncled, in a crowded cluster. Dry, open pine woods, in sandy soil.

3. L. canescens, Lehm. PUCCOON, INDIAN PAINT. Perennial.
Clothed with soft hairs, 8-12 in. high. Flowers axillary and sessile.
Corolla appendaged, not woolly within, showy, orange-yellow. Banks
and open woods.

VII. ECHIUM, Tourn.

Herbs or sometimes shrubs, usually stout, coarse, and hairy.
Leaves entire. • Flowers white, reddish-purple or blue, in
spiked or panicled racemes. Calyx 5-parted. Corolla-tube
cylindrical . or funnel-shaped; the throat dilated; the limb
with 5 unequal lobes. Filaments unequal, adnate to the
corolla below, projecting from the corolla. Style thread-like,
stigma 2-lobed. Nutlets 4, ovoid or top-shaped, wrinkled.

1. E. vulgare, L. BLUE THISTLE, BLUE WEED, BLUE DEVILS,

Stems 1-3 ft. high, more or less erect, leafy, covered with stinging

192 FOUNDATIONS OF BOTANY

hairs. Root-leaves lanceolate or oblong, petioled, 4-8 in. long;
stem-leaves sessile, acute, rounded at the base. Flowers showy,
reddish-purple in the bud, changing to bright blue. A very trouble-
some weed, especially in fallow fields. Introduced from Europe.

86. VERBENACE^. VERBENA FAMILY.

Herbs, shrubs, or trees. Leaves opposite or whorled, with-
out stipules. Flowers irregular, in bracted cymes. Calyx
free from the ovary, cleft or toothed. Corolla free from the
ovary, tubular, usually more or less 2-lipped. Stamens usually
4, 2 long and 2 short, inserted on the corolla-tube. Ovary
usually 2-4-celled (in Phryma, 1-celled), with the style spring-
ing from its summit.

I. VERBENA, Tourn.

Annual or perennial herbs. Leaves simple, opposite, ser-
rate or pinnately lobed. Flowers in terminal spikes which
become much elongated in fruit. Calyx tubular, 5-ribbed,
5-toothed. Corolla salver-form, or funnel-form, the tube often
curved, bearded in the throat, limb spreading, 5-lobed, often
somewhat 2-lipped. Stamens 4, 2 long and 2 short, rarely
only 2, included. Ovary 2-4-celled, 2-4-ovuled ; style slen-
der, 2-lobed. Fruit 2-4 smooth or roughened, 1-seeded nut-
lets. [Several of the commonest species are tall, coarse herbs
which blossom too late for school study.]*

1. V. offlcinalis, L. EUROPEAN VERVAIN. Annual ; stem erect,
slender, nearly or quite smooth, branching, 1-3 ft. high. Leaves
ovate to obovate in outline, pinnately lobed or divided, narrowed
and entire toward the base, downy beneath ; petioles margined.
Spikes several, very slender; flowers small, purple, bracts shorter
than the calyx. In fields and waste places; introduced from
Europe.*

2. V. angustifolia, Michx. NARROW-LEAVED VERVAIN. Peren-
nial, rough-hairy ; stem simple, or branched below, from a creeping
base, 1-2 ft. high. Leaves lanceolate to spatulate, obtuse and toothed
at the apex, tapering to a sessile base. Spike peduncled, slender,
close-flowered ; bracts about the length of the calyx. Corolla purple,
tube slightly curved, £ in. long. In dry, open woods.*

DICOTYLEDONOUS PLANTS 193

3. V. Aubletia, L. VERBENA. A slender-stemmed, somewhat
reclining annual, 1 ft. or less in height. Leaves ovate or nearly so,
wedge-shaped at the base, lobed and toothed or 3-cleft. Flowers
showy, reddish-purple or lilac (seldom white), in a peduncled spike.
Calyx-teeth as long as or longer than the bracts. Corolla very
slightly bearded in the throat. In dry prairie soil and open woods,
also cultivated. [Other somewhat similar cultivated species are
from Brazil.]

H. CALLICARPA, L.

Shrubs. Leaves simple, petioled, opposite or whorled, glan-
dular-dotted. Flowers in axillary cymes. Calyx 4-toothed or
entire. Corolla funnel-form, 4-clef t, regular ; stamens 4, equal,
proj ecting. Ovary 4-ovuled ; style slender ; stigma knobbed.
Fruit a 1-4-seeded berry.*

1. C. americana, L. FRENCH MULBERRY, MEXICAN MULBERRY.

Shrubs, with star-shaped, glandular or scurfy down, widely branched,
3-8 ft. high. Leaves ovate to oblong, acute at each end, crenate-
serrate, rough above, downy beneath, glandular-dotted ; petioles slen-
der. Cymes many-flowered, the peduncle as long as the petiole,
pedicels short. Calyx cup-shaped, the teeth short. Corolla double
the length of the calyx, blue. Fruit violet-purple, very conspicuous
in autumn. Common in fields and thickets S.*

87. LABIATJE. MINT FAMILY.

Mostly herbs, with square stems and opposite, more or
less aromatic leaves, without stipules. Flowers generally
in cyme-like axillary clusters, which are often grouped into
terminal spikes or racemes. Calyx tubular, usually 2-lipped,
persistent. Corolla usually 2-lipped (Fig. 148). Stamens 4
(2 long and 2 short) or only 2. Ovary free, with 4 deep lobes,
which surround the base of the style. Fruit consisting of 4
nutlets, ripening inside the base of the calyx.

Stamens 4. A-

(a) 'Calyx 2-lipped. *

Lips entire. Scutellaria, I.

Lips toothed and cleft. Plants not aromatic.

Brunella, IV.

194 FOUNDATIONS OF BOTANY

Lips toothed and cleft. Plants aromatic. Leaves
extremely small. Thymus, IX.

(b) Calyx not 2-lipped, or not much so.

Calyx tubular, 5-10-toothed. Stamens not projecting
from tube of corolla. Marrubium, II.

Calyx tubular, with 5 equal teeth. Stamens under
upper lip of corolla. Nepeta, III.

Calyx tubular, bell-shaped, with 5 awl-shaped teeth.
Stamens not turned down after maturing.

Lamiurn, V.

Calyx top-shaped, with spreading spiny teeth.

Leonurus, VI.

Calyx as in No. 5. Stamens turned down after ma-
turing. Stachys, VII.

Stamens' 2. . Salvia, VIII.

I. SCUTELLARIA, L.

Mostly slender herbs, not aromatic. Flowers solitary or in
pairs, axillary or in terminal spikes or racemes. Calyx bell-
shaped, 2-lipped, the upper part swollen into a helmet-shaped
pouch ; mouth of the calyx closed after flowering. Corolla-
tube long, naked inside. Stamens 4, the anthers meeting in
pairs, hairy-fringed. Style with a very short upper lobe.
[The species here described are not the commonest ones, but
most of the others grow in damp soil and bloom later.]

1. S. serrata, Andrews. SKULLCAP. Stem not much branched,
1-3 ft. high. Stem-leaves serrate, taper-pointed at both ends, ovate
or nearly so. Racemes single, loose. Calyx rather hairy. Corolla
1 in. long, the lips of equal length. Woods.

2. S. pilosa, Michx. HAIRY SKULLCAP. Stem more or less hairy,
not much if at all branched, 1-3 ft. high. Leaves a few distant
pairs, diamond-ovate, oblong-ovate, or roundish-ovate, scalloped,
obtuse, the lower heart-shaped or nearly truncate at the base, with
long petioles. Racemes short, few-flowered. Corolla £ in. long,

DICOTYLEDONOUS PLANTS 195

tube whitish, lips blue, the lower one rather shorter. Open wood-
lands and dry soil.

3. S. integrifolia, L. LARGE-FLOWERED SKULLCAP. Stem cov-
ered with fine, grayish down, usually unbranched, 1-2 ft. high.
Leaves lance-oblong or nearly linear, mostly entire, obtuse, with very
short petioles. Corolla 1 in. long, tube pale, lips large and spread-
ing, blue. Dry ground.

II. MARRUBIUM, Tourn.

Perennial, downy, or woolly herbs. Whorls of flowers axil-
lary ; flowers small; bracts leaf -like. Calyx tubular, 5-10-
toothed, teeth somewhat spiny. Corolla short ; upper lip
erect, lower spreading, 3-cleft, the middle lobe broadest.
Stamens 4, not projecting. Lobes of the stigma short and
blunt.

1. M. vulgare, L. HOREHOUND. Stems somewhat reclining,
stout, branching, leafy, 1-1£ ft. high. Leaves broadly ovate, heart-
shaped or wedge-shaped at the base, scalloped, leathery and wrinkled.
Whorls of flowers dense. Calyx-teeth hooked at the tip. Corolla £
in. long, white. Cultivated from Europe as an herb (used in prepa-
ration of horehound candy) and somewhat naturalized.

m. NEPETA, L.

Erect or prostrate herbs. Whorls of flowers axillary or ter-
minal; flowers blue or white. Calyx tubular, 15-ribbed,
5-toothed. Corolla-tube slender below, dilated at the throat,
naked ; upper lip notched or 2-cleft ; lower lip 3-cleft, middle
lobe large. Stamens 4, ascending under the upper lip, the
upper pair longer. Lobes of the stigma awl-shaped.

1. N. Cataria, L. CATNIP. Stem grayish, downy, 2-3 ft. high,
branched, very leafy. Leaves large, ovate-heart-shaped, deeply scal-
loped, serrate, white and downy beneath. Corolla about £ in. long,
whitish with purple dots. Introduced from Europe ; a common
weed about dooryards.

2. N. Glechoma, Benth. GROUND IVY, GILL-OVER-T HE-GROUND,
CREEPING CHARLEY, CROW-VICTUALVS, ROBIN-RUNAWAY. Creep-
ing. Leaves roundish, kidney-shaped, and crenate. Corolla bluish-
purple, three times as long as the calyx. Introduced from Europe,
common in damp places about houses and gardens.

196 FOUNDATIONS OF BOTANY

IV. BRUNELLA, Tourn.

Perennials, with stems simple or nearly so, and sessile,
3-flowered flower-clusters in the axils of kidney-shaped
bracts, the whole forming a spike or head. Calyx tubular-
bell-shaped, somewhat 10-ribbed, upper lip broad, 3-toothed,
the teeth short, lower lip with 2 longer teeth. Upper lip of
the corolla upright, arched, and entire, the lower spreading,
reflexed, fringed, and 3-cleft. Stamens 4, reaching up under
the upper lip, with the tips of the filaments 2-toothed, only
one tooth anther-bearing.

1. B. vulgaris, L. SELF-HEAL, HEAL-ALL, CARPENTER-WEED.
Leaves with petioles, ovate-oblong, either entire or toothed, often
somewhat hairy. Corolla usually blue or bluish, somewhat longer
than the brown-purple calyx. Open woods and fields everywhere.

V. LAMIUM, L.

Annual or perennial hairy herbs. Calyx tubular-bell-
shaped, 5-veined, with 5 awl-pointed teeth of nearly equal
length. Corolla with dilated throat, upper lip arched, middle
lobe of the lower lip notched, the lateral lobes small, close to
the throat of the corolla. Stamens 4, rising beneath the
upper lip.

1. L. amplexicaule, L. HEN-BIT, DEAD NETTLE. An annual or
biennial weed. Leaves roundish, deeply scalloped, the lower ones
petioled, the upper sessile and clasping. Corolla sometimes f in.
long, downy, rose-colored or purplish. Introduced from Europe ;
not uncommon about gardens and dooryards.

2. L. purpureum, L. Stem 6-18 in. high, silky-hairy or nearly
smooth, reclining below, branched from the base. Leaves long-peti-
oled, obtuse, heart-shaped, scalloped. Whorls of flowers mostly
terminal, crowded. Corolla £-| in. long, purple (rarely white).
Introduced from Europe.

VI. LEONURUS, L.

Erect herbs. Leaves lobed. Whorls of flowers axillary,
densely flowered, scattered j bractlets awl-shaped ; flowers
small, pink or white. Calyx 5-nerved, top-shaped, with 5
rather spiny, spreading teeth. Corolla with upper lip erect

DICOTYLEDONOUS PLANTS 197

and entire, lower 3-cleft. Stamens 4 ; anthers joined in pairs.
Nutlets with. 3 projecting angles, their sides channeled.

1. L. cardiaca, L. MOTHERWORT. Stem 2-4 ft. high, prominently
angled, stiff, stout, upright, very leafy. Leaves palmately lobed or
cleft ; radical ones long-petioled ; lower stem-leaves many-cleft, the
upper ones 3-cleft, prominently nerved, the divisions acute. Corolla
£ in. long, pale rose-color, the upper lip and outside of the tube
densely soft-bearded. Common about dooryards and fence-rows.
Introduced from Europe.

VII. STACHYS, Tourn.

Herbs, rarely shrubs. Leaves scalloped or serrate. Whorls
of flowers 2 or more flowered, usually in terminal racemes.
Calyx nearly bell-shaped, 5-toothed. Corolla-tube cylindrical,
usually with a ring of hairs inside, not dilated at the throat ;
upper lip erect or spreading; lower spreading, 3-lobed, the
middle lobe largest. Stamens 4, the 2 lower longest.

1. S. palustris, L. Perennial; stem erect, 4-angled, 2-3 ft. high,
hairy, especially on the angles, with projecting or reflexed hairs,
leafy. Stem-leaves short-petioled or sessile, ovate-lanceolate or
oblong-lanceolate, scalloped-serrate, coarsely or finely downy, round-
ish at the base, rather obtuse at the tip. Calyx bristly, the lance-
awl-shaped teeth rather spiny. Upper lip of the corolla downy. In
wet soil, especially N.

2. S. aspera, Michx. Taller than No. 1 ; angles of the stem covered
with stiff reflexed bristles, but the sides often smooth. Leaves ser-
rate, nearly all with distinct petioles. Calyx usually smooth. Corolla
smooth throughout. Damp thickets and along streams.

Vm. SALVIA, L.

Annual, biennial, or perennial herbs, or sometimes shrubby.
Flowers in spikes, racemes, or panicles, usually showy. Calyx
tubular or bell shaped, not bearded in the throat, 2-lipped,
the upper lip entire or 3-toothed, the lower 2-cleft. Corolla
2-lipped, the upper lip entire or notched, the lower spread-
ing, 3-lobed, with the middle lobe longer. Stamens 2, short,
anthers 2-celled, the upper cell fertile, the lower imperfect.
Style 2-cleft. Nutlets smooth.*

198 FOUNDATIONS OF BOTANY

1. S. lyrata, L. LYRE-LEAVED SALVIA, Biennial or perennial;
stem erect, sparingly branched above, rough-hairy, 1-2 ft. high.
Leaves mostly basal, spreading, lyrate-pinnatifid, usually purple,
stem-leaves small, sessile or short-petioled. Racemes many-flowered,
whorls about 6-flowered. Calyx-teeth short on the upper lip, long
and awl-shaped on the lower. Corolla blue or purple, the tube
about 1 in. long, dilated upward. On dry soil.*

2. S. officinalis, L. GARDEN SAGE. Stem shrubby, slender, much
branched below, 1 ft. high. Leaves grayish-green, lance-oblong, cre-
nate, wrinkled. Flowers in terminal spikes, whorls several-flowered.
Corolla blue, upper lip strongly arched, about equaling the lower.
Introduced from Europe and a common garden herb.*

IX. THYMUS, L.

Small, much-branched shrubs, very aromatic. Leaves small,
entire, margins often rolled under. Whorls of flowers few-
flowered, in loose or close spikes ; bracts very small ; flowers
usually purple. Calyx ovoid, 2-lipped, upper lip 3-toothed,
lower 2-cleft, woolly in the throat. Corolla slightly 2-lipped.
Stamens 4, usually projecting from the flower, straight, lower
pair longer.

1. T. Serpyllum, L. CREEPING THYME. Smooth or hairy, stem
prostrate, the flowering branches somewhat ascending. Leaves ^— \
in. long, flat, ovate or obovate-lanceolate, obtuse. Flowers crowded
in spikes at the end of the branches. Corolla rose-purple, 3— f in.
long. Becoming introduced from Europe.

2. T. vulgaris, L. GARDEN THYME. More erect than No. 1.
Leaves somewhat curled under at the edges. Flower-clusters shorter
and not all terminal. Corolla pale purple. Cultivated from Europe
as an herb.

88. SOLANACE^. NIGHTSHADE FAMILY.

Mostly tropical herbs or shrubs (rarely trees). Leaves
usually alternate, without stipules. Flowers regular, borne
on bractless pedicels at or above the leaf axils, or in cymes.
Calyx free from the ovary, 5-cleft, usually persistent. Corolla
hypogynous, wheel-shaped, bell-shaped, or salver-shaped, 5-
lobed. Stamens 5, short, inserted on the corolla-tube. Ovary
2-celled or imperfectly 4-celled ; style simple ; stigma simple
or lobed. Fruit a many-seeded capsule or berry.

DICOTYLEDONOUS PLANTS 199

I. LYCIUM, L.

Shrubs or woody vines, often spiny. Leaves entire, alter-
nate, often fascicled. Flowers solitary or clustered, terminal
or axillary. Calyx persistent, 4-5-lobed or toothed, not en-
larged in fruit. Corolla funnel-form or bell-shaped, the limb
4-5-lobed, the lobes obtuse. Stamens 4-5, projecting. Ovary
2-celled ; style single ; stigma obtuse. Fruit a many-seeded
berry.1*

1. L. vulgare, Dunal. MATRIMONY VINE. Stem slender, branch-
ing, twining or trailing, 6-15 ft. long; branches angled, spiny.
Leaves elliptical, smooth, entire, sessile, or short-petioled. Flowers
solitary or few in the axils ; peduncles long and slender. Corolla
spreading, greenish-purple, ^-£ in. wide. Berry oval, orange-red.
Introduced from Africa, and often planted for covering trellises.*

II. SOLANUM, Toura.

Herbs or shrubs ; stems often prickly, sometimes climbing.
Leaves alternate, often nearly or quite opposite. Flowers
clustered, the peduncles often opposite or above the axils.
Calyx spreading, 5-toothed or 5-cleft, persistent. Corolla
wheel-shaped, 5-lobed. Stamens 5, projecting, the filaments
very short, the anthers long and meeting about the style.
Ovary 2-celled ; style slender. Fruit a many-seeded, juicy
berry.*

1. S. Dulcamara, L. BITTERSWEET. Perennial. Stems rather
shrubby, long, and climbing. Leaves heart-shaped, or some of them
with irregular lobes, or ear-like leaflets at the base. Flowers blue
or purple, somewhat cymose. Berries showy, of many shades of
orange and red in the same cluster, according to their maturity.

2. S. nigrum, L. NIGHTSHADE. Annual; stem smooth, or
downy with simple hairs, erect, diffusely branched ; branches wing-
angled, 1-3 ft. high. Leaves ovate, irregularly toothed or entire,
somewhat inequilateral, petioled. Flowers in lateral, peduncled um-
bels, small, white, drooping. Calyx-lobes obtuse; corolla £-£ in.
wide; filaments downy; berries globose, smooth, black when ripe.
Common in cultivated fields and waste places.*

3. S. carolinense, L. HORSE NETTLE. Perennial; stem erect,
branched, downy with star-shaped hairs, armed with straight, yellow
prickles, 1-3 ft. high. Leaves ovate-oblong, deeply toothed or lobed,

200 FOUNDATIONS OF BOTANY

acute at the apex, abruptly contracted to the short petiole, prickly
on the veins. Racemes lateral, few-flowered ; pedicels recurved in
fruit. Calyx-lobes taper-pointed. Corolla deeply angular-lobed,
blue or white ; berry globose, smooth, yellow. A common weed.*

4. S. rostratum, Dunal. SAND BUR, BUFFALO BUR. Annual;
the whole plant beset with yellow prickles ; stem erect, diff usely
branched, 1-2 ft. high. Leaves broadly oval or ovate in outline,
deeply pinnately lobed or parted, petioled, downy, with star-shaped
hairs. Racemes few-flowered ; pedicels erect in fruit. Calyx very
prickly, becoming enlarged and enclosing the fruit. Corolla bright
yellow, 5-angled, about 1 in. broad. Introduced from the West,
and becoming a troublesome weed in some places.*

5. S. tuberosum, L. IRISH POTATO. Annual; stem diffusely
branched, downy, underground branches numerous and tuber-bearing.
Leaves irregularly pinnatifid and divided. Flowers in cymose clus-
ters, white or purple, with prominent yellow anthers ; pedicels
jointed. Corolla 5-angled, |-1 in. broad. Fruit a globose, greenish-
yellow, many-seeded berry, about £ in. in diameter. Cultivated from
Chili*

HI. LYCOPERSICUM, Tourn.

Annual ; stem diffusely branched. Leaves pinnately divided.
Flowers in raceme-like clusters on peduncles opposite the
leaves. Calyx 5-many-parted, persistent. Corolla wheel-
shaped, 5-6-parted. Stamens 5-6, inserted in the short tube
of the corolla, filaments short, anthers elongated. Ovary
2-several-celled, style and stigma simple. Fruit a many-
seeded berry.*

1. L. esculentum, Mill. TOMATO. Stem diffusely branched, at
length leaning over, furrowed and angled below, sticky-hairy, 3-5
ft. long. Leaves irregularly lobed and pinnatifid, petioled. Calyx-
lobes linear, about as long as the yellow corolla. Fruit (in the wild
state) globose or ovoid, red or yellow, £- £ in. in diameter, but greatly
enlarged in cultivation. Common in cultivation from tropical
America.*

IV. DATURA, L.

Annual or perennial, strong-scented herbs ; stems tall and
branching. Leaves petioled, entire or lobed. Flowers large, soli-
tary in the forks of the branches. Calyx tubular, 5-toothed
or lobed, the upper part deciduous and the lower persistent.
Corolla funnel-form, 5-angled. Stamens 5, inserted in the

DICOTYLEDONOUS PLANTS 201

corolla-tube. Ovary 2-celled or imperfectly 4-celled ; style
filiform ; stigma 2-lobed. Fruit a spiny, 4-valved, many-seeded
capsule.*

1. D. Stramonium, L. JIMSON-WEED. Annual ; stem smooth,
green, stout, forking above, 1—4 ft. high. Leaves ovate to oblong-
ovate, acute at the apex, narrowed at the base, sinuate-toothed,
petioled. Calyx 5-angled. Corolla white, about 4 in. long. Capsule
ovoid, erect, 2 in. long. A common weed ; poisonous. Introduced
from Asia.*

2. D. Tatula, L. Taller, with a purple stem. Flowers rather
later than No. 1 ; corolla violet-tinged.

V. PETUNIA, Juss.

Herbs ; leaves alternate and entire. Divisions of the calyx
oblong-spatulate. Corolla showy, spreading funnel-shaped,
not perfectly regular. Stamens 5, somewhat unequal in
length, inserted in the middle of the corolla-tube and not
projecting beyond it. Capsule 2-celled, containing many very
small seeds.

1. P. violacea, Lindl. COMMON PETUNIA. Stems rather weak
and reclining. Leaves covered with clammy down. Corolla vary-
ing from pale pink to bright purplish-red, often variegated, with
a broad, inflated tube, which is hardly twice as long as the calyx.
Cultivated annual from South America.

2. P. nyctaginiflora, Juss. WHITE PETUNIA. Leaves somewhat
petioled. Tube of corolla long and slender. Flowers white. Culti-
vated from South America. This and the preceding species much
mixed by hybridization.

89. SCROPHULARIACEJE. FIGWORT FAMILY.

Mostly herbs, with irregular flowers. Calyx free from the
ovary and persistent. Corolla 2-lipped or otherwise more or
less irregular. Stamens usually 2 long and 2 short, or only
2 in all, inserted on the corolla-tube, often 1 or 3 of them
imperfectly developed. Pistil consisting of a 2-celled and
usually many-ovuled ovary, with a single style and an entire
or 2-lobed stigma.

202 FOUNDATIONS OF BOTANY

Corolla wheel-shaped, stamens 5. Verbascum, I.

Corolla wheel-shaped or salver-shaped, nearly regular, stamens 2.

Veronica, VI.

Corolla 2-lipped, the mouth closed by a palate, tubular below, a

spur at the base. Linaria, II.

Corolla 2-lipped, the mouth closed by a palate, tubular below, a

short, broad pouch at the base. Antirrhinum, III.

Corolla decidedly 2-lipped.

Stamens with anthers 2. Gratiola, V.

Stamens 4, with a fifth antherless filament. Pentstemon, IV.
Stamens 4, the anther-cells unequal. Castilleia, VII.

Stamens 4, the anther-cells equal. Pedicularis, VIII.

I. VERBASCUM, L.

Biennial ; stem tall, erect. Leaves alternate. Flowers in
spikes, racemes or panicles. Calyx deeply 5-cleft. Corolla
wheel-shaped, 5-lobed, the lobes nearly equal. Stamens 5,
unequal, declined, some or all of the filaments bearded.
Style flattened at the apex. Fruit a globose capsule ; seeds
roughened.*

1. V. Blattaria, L. MOTH MULLEIN. Stem erect, slender, sim-
ple or sparingly branched, smooth below, downy above, 2-4 ft. high.
Leaves oblong to lanceolate, acute at the apex, obtuse or truncate at
the base, dentate to pinnately lobed, the lower petioled, the upper
sessile and clasping. Raceme long and loose, glandular-downy,
pedicels bracted. Corolla white or yellow, marked with brown on
the back, about 1 in. wide. Filaments all bearded with purple
hairs. Capsule longer than the calyx. Common in fields and waste
places ; introduced from EuTope.*

n. LINARIA, Tourn.

Herbs, rarely shrubby. Lower leaves opposite, whorled or
alternate. Flowers in bracted racemes or spikes or axillary
and solitary. Calyx 5-parted. Corolla 2-lipped, the tube
spurred. Stamens 4, with sometimes a rudiment of a fifth.
Stigma notched or 2-lobed. Capsule ovoid or globose ; cells
nearly equal.

DICOTYLEDONOUS PLANTS 203

1. L. vulgaris, Miller. BUTTER-AND-EGGS, JACOB'S LADDER,
WILD FLAX. A perennial, erect, smooth herb, with a bloom, stem
1-2 ft. high. Leaves linear or lanceolate, 1-3 in. long, often
whorled. Racemes densely flowered. Sepals shorter than the spur.
Corolla yellow, f-1 in. long ; spur parallel to and as long as the
tube ; throat closed by a palate-like fold. Common in dry fields and
pastures and along roadsides ; introduced from Europe.

2. L. canadensis, Dumont. TOAD-FLAX. Biennial ; flowering
stems erect, slender, rarely branched, smooth, 1-2 ft. high, sterile
stems prostrate, with opposite or whorled leaves, 2-6 in. long.
Leaves linear, entire, sessile. Racemes erect, slender ; pedicels
erect, as long as the calyx. Corolla small, blue and white, the spur
thread-like, curved, longer than the pedicels. Capsule 2-valved, the
valves 3-toothed. On dry or cultivated ground E.

III. ANTIRRHINUM, Tourn.

Annual or perennial herbs. Leaves entire, rarely lobed,
the lower ones opposite, the upper alternate. Flowers axillary
and solitary or racemed and bracted. Calyx 5-parted.
Corolla 2-lipped. The tube with a sac, the broad bearded
palate closing the throat. Stamens 4» Stigma with 2 short
lobes. Capsule 2-celled, the upper cell opening by 1 pore,
the lower by 2.

1. A. majus, L. SNAPDRAGON. Perennial; stem erect, smooth
below, glandular-downy above, 1-2 ft. high. Leaves linear to
oblong-lanceolate, entire, smooth, sometimes fleshy, sessile or short-
petioled. Flowers in a terminal raceme ; pedicels short, stout,
erect in fruit. Corolla 1^-2 in. long, of many colors. Capsule
oblique, the persistent base of the style bent forward. Common in
gardens, cultivated from Europe, and often escaped.*

IV. PENTSTEMON, Mitchell.

Perennials, the stems branching from the base, unbranched
above. Leaves opposite. Flowers usually showy in a termi-
nal panicle. Calyx of 5 nearly distinct sepals. Corolla
tubular, the tube wide above and narrowed below ; 2-lipped.
Stamens 4, 2 long and 2 short, with a fifth antherless filament
as long as the others, its upper half bearded. Capsule ovoid,
acute.

1. P. pubescens, Solander. Stem somewhat sticky-downy, 1-2
ft. high. Leaves varying from oblong to lanceolate, 2-4 in, long,

204 FOUNDATIONS OF BOTANY

usually with small teeth. Flower-cluster narrow. Corolla dingy
violet, purplish, or whitish, the tube not much widened above, its
throat nearly closed by a hairy palate. Sterile filament much
bearded. Dry hillsides or stony ground.

2. P. laevigatus, Solander. Stem usually smooth except the
flower-cluster, 2-4 ft. high. Leaves shining, those of the stem
ovate-lanceolate or broadly lanceolate, 2-5 in. long, with a somewhat
heart-shaped clasping base. Flower-cluster broader than in Xo. 1.
Corolla white or oftener purplish, suddenly widened above, the throat
not closed. Sterile filament slightly bearded toward the top. In
rich soil.

3. P. barbatus, Nutt. Stems slender and rod-like, 3-4 ft. high.
Leaves lanceolate, entire. Flower-cluster long and loosely flowered.
Flowers showy, drooping. Corolla-tube slender, scarlet, somewhat
bearded in the throat. Sterile filament beardless. Cultivated from
Mexico.

V. GRATIOLA, L.

Low herbs growing in wet or damp ground. Leaves oppo-
site, sessile. Flowers axillary and solitary, peduncled. Calyx
5-parted. usually with 2 braetlets at the base. Corolla some-
what 2-lipped. Perfect stamens 2. Stigma enlarged or
2-lipped. Pod 4-valved, many-seeded.

1. G. virginiana, L. Stem cylindrical, 4-10 in. long, branching
from the base. Leaves f-H in. long, varying from lance-oblong to
spatulate. Corolla pale yellow, tinged with red. Common in muddy
soil, along brooksides, etc.

VT» VERONICA, Tourn.

Herbs or shrubs. Lower leaves or all the leaves opposite.
rarely whorled. Flowers in axillary or terminal racemes.
rarely solitary. Calyx usually 4-parted. Corolla wheel-
shaped or somewhat bell-shaped; limb usually 4-cleft, spread-
ing, the side lobes commonly narrower. Stamens 2, inserted
on the corolla-tube at the sides of the upper lobe, projecting.
Stigma somewhat knobbed. Capsule generally flattened, often
notched at the apex, 2-celled, few-m any-seeded.

1. V. americana, Schweinitz. BROOKLIME. A perennial smooth
herb, somewhat prostrate below, but the upper parts of the stem
erect, 8-15 in. high. Leaves 1-2 in. long, lance-ovate or oblong,

DICOTYLEDONOUS PLANTS 205

serrate, short-petioled. Racemes 2-4 in. long, axillary and opposite.
Corolla wheel-shaped, blue. Capsule swollen, roundish. Muddy
soil about springs and brooks.

2. V. officinalis, L. COMMON SPEEDWELL, GYPSY WEED.
Perennial. Roughish-downy, with the prostrate stems spreading
and rooting. Leaves wedge-oblong or nearly so, obtuse, serrate,
somewhat petioled. Racemes dense, of many pale bluish flowers.
Capsule rather large, inversely heart-shaped arid somewhat trian-
gular. Dry hillsides, open woods and fields.

3. V. serpyllifolia, L. THYME-LEAVED SPEEDWELL. Perennial.
Smooth or nearly so ; branching and creeping below, but with nearly
simple ascending shoots, 2-4 in. high. Leaves slightly crenate, the
lowest ones petioled and roundish, those farther up ovate or oblong,
the uppermost ones mere bracts. Raceme loosely flowered. Corolla
nearly white or pale blue, beautifully striped with darker lines ; cap-
sule inversely heart-shaped, its width greater than its length. Damp
grassy ground ; a common weed in lawns.

4. V. peregrina, L. PURSLANE SPEEDWELL. A homely, rather
fleshy, somewhat erect-branched annual weed, 4-9 in. high. Lowest
leaves petioled, oblong, somewhat toothed, those above them sessile,
the uppermost ones broadly linear and entire. Flowers solitary,
inconspicuous, whitish, barely pediceled, appearing to spring from
the axils of the small floral leaves. Corolla shorter than the calyx.
Roundish, barely notched, many-seeded. Common in damp ground,
in fields and gardens.

VII. CASTILLEIA, Mutis.

Herbs parasitic on the roots of other plants. Leaves alter-
nate ; the floral ones usually colored at the tip and more showy
than the flowers. Flowers yellow or purplish in terminal
leafy spikes. Calyx tubular, flattened, 2-4-cleft. Corolla-tube
included within the calyx; upper lip of the corolla very long,
linear, arched, and enclosing the stamens, 2 of which are long
and 2 short. Ovary many-ovuled.

1. C. coccinea, Sprengel. SCARLET PAINTED CUP, PAINT-BRUSH,
INDIAN PINK, PRAIRIE FIRE, WICKAKEE. A hairy, simple-stemmed
herb. Annual or biennial. Root-leaves clustered obovate or oblong.
Stem-leaves cut ; floral leaves 3-5 cleft and bright scarlet (occasion-
ally yellow) toward the tips, as though dipped in a scarlet dye. Calyx
nearly as long as th# pale yellow corolla, 2-cleft. The spikes are
often very broad, making this one of the most conspicuous of our
native flowers. Damp, sandy ground, or on bluffs near streams;
sometimes in marshes.

206 FOUNDATIONS OF BOTANY

VIII. PEDICULARIS, Tourn.

Perennial herbs, with the lower leaves pinnately cut and
the floral ones reduced to bracts. Flowers spiked. Corolla
markedly 2-lipped; the upper lip much flattened laterally and
arched, the lower lip spreading, 3-lobed. Stamens 4, beneath
the upper lip. Capsule 2-celled, tipped with an abrupt point,
several-seeded.

1. P. canadensis, L. COMMON LOUSEWORT. Hairy, with clus-
tered simple stems, 1 ft. high or less. Leaves petioled, the lower-
most ones pinnately parted, the others somewhat pinnately cut ; spike
short, closely flowered and leafy-bracted ; calyx split down the front ;
corolla greenish-yellow and purplish, with its upper lip hood-like,
curved under, and with 2 awl-like teeth near the end ; capsule flat,
broadly sword-shaped. Knolls and openings among thickets.

90. BIGNONIACE^E. BIGNONIA FAMILY.

Trees or shrubs, often twining or climbing, rarely herbs.
Leaves usually opposite, without stipules. Flowers showy,
irregular. Corolla tubular, with a widened throat and a
5-lobed limb. Stamens usually 2 long and 2 short, or only 2.
Ovary free from the calyx, 2-celled or rarely 1-celled, with
many ovules. Fruit a capsule ; seeds large, winged.

I. BIGNONIA, Tourn.

Woody vines. Leaves opposite, compound, usually ten-
dril-bearing. Flowers large, in axillary clusters. Calyx
cup-shaped, truncate, or undulate-toothed. Corolla spreading-
tubular, somewhat 2-lipped, the lobes rounded. Stamens 4,
2 long and 2 short. Capsule linear, flattened parallel with
the partition, the two valves separating from the partition at
maturity. Seeds flat, broadly winged.*

1. B. capreolata, L. CROSS-VINE. Stem climbing high, a trans-
verse section of the older stems showing a conspicuous cross formed
by the 4 medullary rays; branches smooth. Leaves evergreen,
petioled ; leaflets 2, ovate, taper-pointed with a blunt apex, heart-
shaped at the base, entire, stalked, upper leaflets transformed into

DICOTYLEDONOUS PLANTS 207

branching tendrils. Flowers numerous, short-peduncled. Corolla
2 in. long, reddish-brown without, yellow within. Capsule 6 in.
long, flat, the valves with a prominent central nerve. Seeds broadly
winged on the sides, short-winged on the ends. Common in woods S.*

H. TECOMA, Juss.

Woody vines, climbing by aerial rootlets. Leaves com-
pound, odd-pinnate. Flowers large, in terminal clusters.
Calyx bell-shaped, unequally 5-toothed. Corolla funnel-form,
enlarged above the calyx, 5-lobed, slightly 2-lipped. Stamens
4, 2 long and 2 short. Capsule slender, spindle-shaped,
slightly compressed contrary to the partition, 2-valved, dehis-
cent. Seeds winged.*

1. T. radicans, Juss. TRUMPET FLOWER, TRUMPET CREEPER.
Stems climbing high by numerous rootlets, bark shreddy. Leaves
deciduous, petioled; leaflets 9-11, ovate to ovate-lanceolate, serrate,
short-stalked, smooth or slightly downy. Flowers in short, terminal
racemes or corymbs. Calyx tubular, f in. long. Corolla 2-3 in. long,
scarlet without, yellow within, the lobes spreading. Capsule 5-6
in. long, curved, often persistent through the winter. Seeds broadly
winged. On borders of fields and in woods S. ; often cultivated.*

III. CATALPA, Scop., Walt.

Small trees. Leaves large, opposite, simple, petioled, decid-
uous. Flowers large and showy, in terminal panicles. Calyx
irregularly 2-lipped. Corolla tubular-bell-shaped, oblique,
5-lobed, 2-lipped. Fertile stamens 2, sterile stamens 3, short.
Fruit a linear, 2-valved, many-seeded capsule. Seeds winged.*

1. C. bignonioides, Walt. CATALPA. A small tree with thin,
rough, gray bark and light, soft, but exceedingly durable wood.
Leaves long-petioled, heart-shaped, entire or palmately 3-lobed, taper-
pointed at the apex, palmately veined, downy. Branches of the
panicle in threes ; flowers large, 1-1 £ in. long, white, variegated
with yellow and purple. Corolla lobes undulate or crisped. Capsule
very slender, 1 ft. or more in length, pendulous. Seeds with long,
fringed wings. On margins of rivers and swamps S., often
cultivated.*

2. C.' speciosa, Warder. CATALPA. A tall tree with very durable
wood. Leaves large, heart-shaped, taper-pointed. Corolla about
2 in. long, almost white, but slightly spotted ; tube inversely conical ;

208 FOUNDATIONS OF BOTANY

limb somewhat oblique, its lower lobe notched. Pod rather stout.
Rich, damp woods, especially S. W. ; often cultivated.

91. OROBANCHACE.2E. BROOM-RAPE FAMILY.

Leafless brownish root-parasites. Kootstock often tuberous,
naked or scaly. Stem usually stout, solitary, scaly. Flowers
spiked or racemed. Sepals 4-5, free from the ovary. Corolla
hypogynous, irregular, the tube curved ; the limb 2-lipped.
Stamens 4, 2 long and 2 short, inserted on the corolla-tube ;
anthers 2-celled, the cells spurred at the base. Ovary 1-celled,
of 2 carpels, style simple, stigma 2-lobed ; ovules many. Cap-
sule 1-celled, 2-valved, few-many-seeded ; seeds very small.

I. CONOPHOLIS, Wallroth.

Stems often clustered, stout, covered with scales which
overlap, the uppermost ones each with, an axillary flower,
thus forming a spike. Calyx irregularly 4-5 cleft, split down
the lower side. Corolla swollen below, decidedly 2-lipped, the
upper lip arched. Stamens projecting.

1. C. americana, Wallroth. SQUAW-ROOT, CANCER-ROOT. Stems
3-6 in. high, yellowish or yellowish-brown. Flowers numerous, in-
conspicuous. Corolla dirty white or pale brown. In oak woods,
not very common.

II. APHYLLON, Mitchell.

Brownish or whitish plants with naked scapes borne on
scaly, mostly underground stems. Calyx regular, 5-cleft.
Corolla 5-lobed, slightly irregular. Stamens not projecting
from the corolla-tube.

1. Aphyllon uniflorum, Gray. ONE-FLOWERED CANCER-ROOT.

Slightly covered with clammy down. Stems very short-branched,
each with 1-3 1-flowered scapes 3-5 in. high. Calyx-lobes lance-
awl-shaped, half as long as the corolla. Corolla yellowish-white,
veiny, purple-tinged, palate with 2 yellow bearded ridges. Damp
woods.

2. A. fasciculatum, Gray. Stem scaly, upright, 3-4 in. high above
ground and generally longer than the numerous 1-flowered pedun-
cles. Calyx-lobes short, triangular. Parasitic on wild species of
Artemisia, etc., in sandy and loamy soil N. W. and W.

DICOTYLEDONOUS PLANTS 209

92. LENTIBULARIACE^:. BLADDEKWORT FAMILY.

Scape-bearing herbs, chiefly aquatic or living in marshes.
Leaves are often thread-like and floating, without stipules.
Flowers irregular. Calyx free from the ovary, persistent.
Corolla hypogynous, 2-lipped, the tube short, spurred at the
base. Stamens 2, opposite the lateral sepals, hypogynous or
inserted on the corolla-tube. Ovary free, 1-celled ; style
short, thick, stigma 2-lipped, ovules many. Capsule 2-valved
or bursting irregularly, many-seeded.

UTRICULARIA, L.

Aquatic or terrestrial herbs, often floating and propagated
by buds which break loose from the plant and sink to the
bottom of the pond or stream during the winter. Leaves of
the aquatic species floating, thread-like, furnished with little
bladders in which animalcules are caught. Flowers often
rather showy, solitary, spiked or racemed. Corolla with its
throat nearly closed by the palate. Capsule globose, bursting
irregularly.

1. U. cornuta, Michx. HORNED BLADDERWORT. Stemless. Leaves
linear and entire or none ; air bladders few or none. Scape erect,
stout, 2-5-flowered, 8-12 in. high. Flowers yellow, fragrant, f in.
wide. Pedicel as long as the calyx. Lips of the corolla obovate,
unequal, the lower longer, abruptly pointed, the sides reflexed, as
long as the horn-shaped, curved spur, throat bearded. Seeds minutely
pitted. In swamps and muddy places.*

2. U. subulata, L. SMALL BLADDERWORT. Scape thread-like,
2-6 in. high. Leaves few and awl-shaped or none ; air bladders few
or none. Racemes zigzag, 1-6-flowered ; pedicels much longer than
the calyx. Corolla yellow, £ in. wide, the lower lip 3-lobed, longer
than the appressed, conical, green-pointed spur. Wet, sandy soil.*

3. U. inflata, Walt. SWOLLEN BLADDERWORT. Perennial ; stem
very slender, floating. Leaves finely dissected, the lower ones scat-
tered, the upper ones whorled; the petioles dilated upward and
inflated, air bladders very numerous. Scape stout, 6-12 in. high,
3-10-flowered. Corolla yellow, about f in. wide, upper lip ovate,
slightly lobed, lower lip 3-lobed, twice the length of the curved,
emarginate spur. Fruit nodding. In ponds and still water.*

210 FOUNDATIONS OF BOTANY

4. U. vulgaris, L. GREATER BLADDERWORT. Stems submerged,
leafy, 1-3 ft. long. Leaves spreading, pinnately cut into very many
thread-like segments which bear many bladders. Scapes 6-12 in.
long, 5-12-flowered, pedicels bent down after flowering. Corolla ^-|
in. long, yellow, upper lip broad and short, palate prominent; spur
conical, pressed close to the under lip. Ponds and slowly flowing
streams.

93. ACANTHACEJE. ACANTHUS FAMILY.

Herbs or shrubs. Leaves opposite or whorled, without
stipules. Flowers irregular, usually with large bracts. Calyx
of 4 or 5 unequal segments which considerably overlap each
other. Corolla 4-5-parted and usually more or less 2-lipped.
Stamens usually 2 long and 2 short, sometimes only 2. Ovary
free from the calyx. Fruit usually a capsule. Seeds not
winged. A large family, mostly tropical, with only a few
insignificant wild species in the northern United States.

I. RUELLIA, Plumier.

Perennial herbs; stems * swollen at the joints and often
between them, somewhat 4-angled. Leaves sessile or short-
petioled, mostly entire. Flowers axillary, solitary or clustered,
showy, white, blue, or purple. Calyx 2-bracted, 5-parted, the
divisions linear and awl-shaped. Corolla-tube slender, often
much elongated, the limb spreading, nearly equally 5-lobed.
Stamens 4, 2 long and 2 short, included or slightly projecting.
Style slender. Capsule slender, narrowed below, 4-12-seeded.*

1. R. strepens, L. SMOOTH RUELLIA. Stem erect, slender,
usually simple, smooth or hairy, 1-3 ft. high. Leaves ovate to
oblong, acute at the apex, narrowed below into a short petiole.
Flowers solitary or in small clusters, sessile or short-peduncle d.
Calyx-lobes shorter than the tube of the corolla, downy or fringed.
Corolla blue, the tube l£-2 in. long, the limb 1-1 £ in. wide. Cap-
sule usually longer than the calyx, smooth, 8-12-seeded. The later
flowers often without a corolla. On rich, dry soil.*

2. R. ciliosa, Pursh. HAIRY RUELLIA. Stem erect, rather stout,
often few-branched above, covered with white hairs, 4-30 in. high.
Leaves oblong to ovate, acute or obtuse at the apex, narrowed and

DICOTYLEDONOUS PLANTS 211

mostly sessile at the base, hairy-fringed. Flowers pale blue, solitary
or 2-3 together. Calyx-lobes bristle-shaped, half the length of the
corolla-tube. Tube of the corolla 2 in. long. Capsule shorter than
the calyx, smooth, 8— 12-seeded. A very variable species, the flowers
often without a corolla. In dry woods and fields S.*

II. DIANTHERA, Gronov.

Perennial herbs ; stem smooth. Leaves opposite, entire or
toothed. Flowers axillary, solitary or clustered, irregular.
Calyx 5-parted. Corolla 2-lipped, upper lip erect, concave,
entire or notched, the lower prominently veined, spreading,
3-lobed. Stamens 2, inserted in the throat of the corolla.
Ovary 2-celled, 4-ovuled, style simple, acute. Capsule flat-
tened, narrowed below into a little stalk.1*

1. D. americana, L. WATER WILLOW. Stem erect, slender, 2-3
ft. high. Leaves lanceolate to linear-lanceolate, taper-pointed at the
apex, narrowed below to the sessile or short-petioled base. Flowers
bracted, in short spikes, on peduncles as long as the leaves. Corolla
pale blue or purple, the tube as long as the lips, lower lip wrinkled.
Capsule about the length of the calyx. In water S.*

94. PLANTAGINACEJE. PLANTAIN FAMILY.

Annual or perennial scape-bearing herbs. Leaves usually
all radical, with parallel ribs. Flowers small, green, usually
spiked, regular and perfect (Fig. 21). Sepals 4, persistent.
Corolla hypogynous, salver-shaped, thin and dry ; lobes 4,
spreading. Stamens 4, usually inserted on the corolla-tube,
filaments thread-like, anthers large and versatile. Ovary free,
usually 2-4-celled ; style thread-like. Fruit a 1-4-celled,
1 or more seeded membranous capsule, which splits open
transversely, the top coming off like a lid.

PL ANT AGO, L.

Characteristics of the genus as given above for the family.

1. P. major, L. PLANTAIN. Perennial, from a very short root-
stock. Leaves ovate to oval, strongly 5-9-ribbed, acute or obtuse at

212

FOUNDATIONS OF BOTANY

the apex, rounded at the base into a long, concave petiole, entire or
toothed, smooth or slightly downy. Scape taller than the leaves,
downy, spike densely flowered ; bracts short, ovate. Flowers per-
fect. Stamens 4, projecting. Capsule ovoid, about twice the length
of the calyx. Common in dooryards.*

2. P. lanceolata, L. RIBGRASS. Biennial or perennial ; soft-
hairy or nearly smooth. Leaves numerous, lanceolate to elliptical,
acute, long-petioled, strongly 3-5-ribbed, entire
or toothed. Scapes much longer than the leaves,
striate-angled, 1-2 ft. high, spike short and dense.
Bracts and sepals ovate. Corolla smooth. Cap-
sule longer than the calyx, 2-seeded. Introduced;
common in meadows.*

3. P. aristata, Michx. LARGE-BRACTED PLAN-
TAIN. Annual. Leaves broadly linear, entire
or sparingly and finely toothed, narrowed below
into a margined petiole, smooth or
silky-downy. Scape longer than the
leaves, 6-10 in. high, spike dense.
Bracts linear, £-1 in. long. Stamens
4 ; capsule 2-seeded, longer than the
calyx. Common on dry soil.*

4. P. heterophylla, Nutt. MANY-
SEEDED PLANTAIN. Annual.
Leaves linear, fleshy, entire, or with
a few spreading teeth, smooth or
slightly downy. Scapes slender, 3-6
in. high, spike very slender, many-
flowered, the lower flowers often
scattered. Bracts ovate, longer than
the sepals. Stamens 2. Capsule
twice the length of the calyx, many-seeded. Common in cultivated
ground, especially S.*

FIG. 21. — Flowers of Plantain

(Plantago), enlarged.
A, earlier stage, pistil mature, sta-
mens not yet appearing outside
the corolla. B, later stage, pistil
withered, stamens mature.

95. RUBIACE^E. MADDER FAMILY.

Herbs, shrubs, or trees. Leaves opposite and entire, with
stipules between them, or appearing whorled since the stipules
resemble the leaves. Flowers always perfect, frequently
dimorphous (as in Houstonia, Mitchella, and Bouvardia).
Calyx-tube adnate to the ovary; limb 3-6-toothed. Corolla
regular, inserted on the calyx-tube, as many-lobed as the
calyx. Stamens equal in number to the divisions of the
corolla. Ovary 2 or more celled. A very large and important

DICOTYLEDONOUS PLANTS 213

family, of which many of the important species, for instance,
the coffee shrub and the cinchona tree, are natives of warm or
tropical climates.

I. HOUSTONIA, L.

Annual, biennial, or perennial herbs ; stems erect or diffuse.
Leaves entire, stipules often only a line connecting the bases
of opposite leaves. Flowers small, solitary, or clustered.
Calyx 4-toothed, persistent. Corolla wheel-shaped to funnel-
form, 4-lobed. Stamens 4. Ovary 2-celled, style slender,
stigmas 2. Fruit a 2-celled, few-many-seeded capsule, open-
ing at the apex, free from the calyx.*

1. H. coerulea, L. BLUETS, INNOCENCE, QUAKER LADIES, EYE-
BRIGHT. Perennial, from very slender rootstocks ; stems tufted,
erect, smooth, forking, 3-6 in. high. Leaves sessile, often hairy-
fringed, the lower spatulate, the upper lanceolate. Flowers solitary,
on slender axillary peduncles. Calyx small. Corolla salver-form,
blue or white, yellow in the throat, smooth, of two forms, the stamens
projecting and the style short in one form, while in the other the
stamens are short and the style projecting. Capsule laterally com-
pressed, 2-lobed, shorter than the calyx. Common on open ground.*

2. H. patens, Ell. SMALL BLUETS. Annual. Stem erect, branched
at the base, forking above, smooth, 2-4 in. high. Lower leaves oval
to ovate, petioled, the upper narrower and sessile. Flowers solitary,
on slender, axillary peduncles, blue or white. Calyx small. Lobes
of the corolla about as long as the tube ; stamens and style project-
ing or included. Capsule compressed, as long as the calyx. Com-
mon on dry, open ground.*

3. H. purpurea, L. LARGE BLUETS. Perennial ; stem stout, erect,
simple or branched, smooth or downy, 4-angled, 6-12 in. high.
Leaves ovate to ovate-lanceolate, sessile or short-petioled, 3-5-nerved,
often hairy-fringed on the margins. Flowers in terminal cymes,
purple to nearly white. Corolla funnel-form, the tube longer than
the limb, hairy within. Stamens and style projecting or included.
Capsule compressed-globose, much shorter than the calyx. In dry,
open woods.*

Var. longifolia, Gray. LONG-LEAVED BLUETS. Perennial. Stem
erect, branched, smooth, 4-angled, 8-12 in. high. Leaves sessile,
the lower- oblanceolate or spatulate, the upper linear, 1-nerved.
Corymbs terminal, few-flowered. Corolla light purple to white, the
lobes much shorter than the tube. Capsule compressed-globose,
nearly as long as the calyx. In dry, open woods.*

214 FOUNDATIONS OF BOTANY

II. BOUVARDIA, Salisb.

Smooth perennials. Leaves lanceolate, thickish. Calyx
4-lobed, the divisions slender. Corolla with a long and nar-
row or rather trumpet-shaped tube and spreading 4-lobed limb.
Anthers 4, inserted in the throat of the corolla, almost sessile.
Stigmas 2, flat. Capsule globular, 2-celled, many-seeded.
Flowers dimorphous.

1. B. triphylla, Salisb. THREE-LEAVED BOUVARDIA. Somewhat
shrubby. Leaves nearly smooth, ovate or oblong-ovate, the lower
ones in threes, the upper ones sometimes in pairs. Corolla scarlet
and slightly downy outside.

2. B. leiantha, Benth. DOWNY-LEAVED BOUVARDIA. Leaves
rather downy. Corolla deep scarlet, smooth outside.

Both species cultivated from Mexico ; in greenhouses.

HI. MITCHELLA, L.

A pretty trailing evergreen herb. Leaves roundish-ovate,
petioled. Flowers fragrant, white or pinkish, dimorphous,
growing in pairs, joined by their ovaries. Calyx -4-toothed.
Corolla funnel-shaped, with the lobes bearded within. Sta-
mens 4, short. Style 1, stigmas 4, slender. Fruit double,
composed of the united ovaries, really a stone-fruit containing
8 seed-like bony nutlets, ripening into tasteless scarlet berries
which cling to the plant through the winter.

1. M. repens, L. PARTRIDGE BERRY, SQUAW VINE, TWO-EYE
BERRY. Common in dry woods, especially under evergreen conif-
erous trees.

IV. GALIUM, L.

Annual or perennial herbs ; steins slender, 4-angled. Leaves
appearing whorled. Flowers small, in axillary or terminal
cymes or panicles, perfect or rarely dioecious. Calyx-tube
short, the teeth minute or wanting. Corolla wheel-shaped,
3-4-lobed. Stamens 3-4, short. Ovary 2-celled, styles 2,
short, united below. Fruit 2, united, sometimes fleshy,
1-seeded carpels which do not split open.*

1. G. Aparine, L. GOOSEGRASS. Annual; stem weak, decum-
bent, sharply 4-angled and with backward pointing prickly hairs,

DICOTYLEDONOUS PLANTS 215

widely branched, 2-4 ft. long. Leaves 6-8 in a whorl, oblanceolate,
prickly-hairy on the margins and midrib. Peduncles axillary,
longer than the leaves, 1-3-flowered ; flowers white. Fruiting pedi-
cels erect ; fruit dry, covered with hooked bristles. In waste
places.*

2. G. circsezans, Michx. WILD LICORICE. Perennial; stems
several, erect, smooth or downy, 12-18 in. high. Leaves 4 in a
whorl, oval to ovate, obtuse at the apex, strongly 3-nerved, downy.
Cymes long-peduncled, repeatedly branched. Flowers nearly sessile,
greenish-purple; pedicels at length recurved. Fruit with hooked
bristles. In dry, open woods S. Easily recognized by the sweet,
licorice-like taste of the leaves.*

3. G. hispidulum, Michx. BEDSTRAW. Perennial, from yellow
roots; stems diffusely branched, smooth or slightly roughened,
downy at the joints, erect or decumbent, 1-2 ft. long. Leaves 4 in
a whorl, narrowly oval, acute, rough on the margins and mid- vein.
Peduncles 1-3-flowered ; flowers white. Pedicels becoming reflexed ;
fruit a bluish-black, roughened berry. On dry, sandy soil.*

4. G. triflorum, Michx. Perennial ; steins reclining or prostrate,
angles rough-bristly. Leaves mostly in sixes, lance-oblong, mucro-
nate. Flowers usually in threes, on slender peduncles. Woodlands,
especially N".

96. CAPRIFOLIACE^. HONEYSUCKLE FAMILY.

Mostly shrubs. Leaves opposite, without true stipules.
Flowers often irregular. Calyx-tube adnate to the ovary.
Corolla tubular or wheel-shaped. Stamens usually as many
as the corolla-lobes and inserted on the corolla-tube. Fruit a
berry, stone-fruit, or capsule.

I. SAMBUCUS, Tourn.

Shrubs with odd-pinnate leaves. Calyx-limb minute or
wanting. Flowers very many, small, white, in compound
cymes. Corolla with a small, somewhat urn-shaped tube and
a flattish, spreading, 5-cleft limb. Stamens 5. Stigmas 3,
sessile. Fruit a globular, pulpy stone-fruit, 3-seeded, appear-
ing like a berry.

1. S. canadensis, L. COMMON ELDER. Stems 5-10 ft. high,
with a thin cylinder of wood surrounding abundant white pith.

216 FOUNDATIONS OF BOTANY

Leaflets 5-11, oblong, taper-pointed, smooth. Cymes flat and often
very large. Fruit purplish-black, insipid or almost nauseous, but
somewhat used in cookery.

2. S. racemosa, L. RED-BERRIED ELDER. More woody, with
brown pith. Leaflets fewer, downy beneath, especially when young.
Cymes panicled and somewhat pyramidal. Fruit scarlet.

H. VIBURNUM, L.

Shrubs or small trees. Leaves simple, entire, dentate or
lobed, with or without stipules. Flowers small, white, in
terminal cymes, the outer flowers of the cyme sometimes
greatly enlarged and sterile. Calyx-tube very small, 5-toothed.
Corolla wheel-shaped or bell-shaped, 5-lobed. Stamens 5, in-
serted in the tube of the corolla. Ovary 1-3-celled, 1-3-
ovuled, but only 1 ovule maturing ; style short, 3-lobed. Fruit
a 1-seeded stone-fruit.*

Flowers around the margin of the cyme without stamens or pistils,
large and showy.

1. V. lantanoides, Michx. . HOBBLE-BUSH, WITCH-HOBBLE. A
shrub about 5 ft. high, with the branches reclining and often root-
ing and forming loops (whence the popular names). Leaves very
large, roundish, abruptly taper-pointed, serrate, with a rusty down
on the petioles and veinlets. Cymes very broad and showy. Fruit
red, not eatable.

2. V. Opulus, L. CRANBERRY TREE, HIGH-BUSH CRANBERRY.
A handsome, upright shrub. Leaves 3-5-ribbed and 3-lobed. Fruit
bright red, juicy, very acid, and used as a substitute for cranberries.
Common N. The form known as " Snowball " with all the flowers
showy and sterile is cultivated from Europe.

Flowers all small and perfect.

3. V. acerifolium, L. MAPLE-LEAVED ARROWWOOD. A slender
shrub 3-6 ft. high. Leaves broadly ovate to heart-shaped, palmately
veined and 3-lobed, serrate or nearly entire, petioled, downy, becom-
ing smooth above. Cymes peduncled, about 7-rayed, 2-3 in. wide ;
sterile flowers none. Fruit oval, black, stone flat, 2-ridged on the
edges. In dry, open woods.*

DICOTYLEDONOUS PLANTS 217

4. V. dentatum, L. ARROWWOOD. A shrub 8-15 ft. high.
Leaves broadly ovate to oval, acute at the apex, rounded or heart-
shaped at the base, coarsely dentate, smooth above, hairy in the
axils of the veins beneath, short-petioled. Cymes long-peduncled,
7-rayed, 2-3 in. wide ; sterile flowers none. Calyx smooth. Fruit
globose, dark blue, stone compressed, grooved on one side. In rich,
damp soil.*

5. V. nudum, L. WITHE-ROD. A shrub 8—12 ft. high. Leaves
ovate to lanceolate, entire or slightly toothed, acute at both ends,
thick, smooth above, the veins prominent beneath ; petiole short.
Cymes short-peduncled, 5-rayed ; sterile flowers none. Fruit ovoid,
blue. Common in swamps.*

6. V. prunifolium, L. BLACK HAW. A small tree, 15-20 ft.
high. Leaves oval to ovate, acute or obtuse at each end, finely and
sharply serrate, smooth and shining above, often slightly downy
beneath ; petioles dilated and rusty-downy. Cymes sessile, large,
4-5-rayed; sterile flowers none. Fruit oval, bluish-black, eatable.
In rich, moist woods.*

HI. SYMPHORICARPOS, Dill.

Shrubs. Leaves short-petioled, deciduous. Flowers in
axillary clusters. Calyx-tube globose, 4-5-toothed. Corolla
bell-shaped, 4-5-lobed, sometimes knobbed at the base, smooth
or hairy within. Stamens 4-5. Ovary 4-celled, 2 of the
cells with a single fertile ovule in each, the other cells with
several abortive ovules ; style slender, stigma knobbed or
2-lobed. Fruit a 4-celled, 2-seeded berry.*

1. S. racemosus, Michx. SNOWBERRY. An ornamental shrub,
2-3 ft. high. Flowers in loose terminal racemes, which are often
leafy. Corolla bell-shaped, much bearded inside, pinkish-white.
Stamens and style not projecting. Berries rather large, snow-white,
remaining long on the branches. Rocky banks, often cultivated.

IV. LINNJEA, Gronov.

A very small, slender, creeping evergreen shrub ; branches
inclined, ending in a slender, erect, 2-flowered peduncle.
Leaves opposite, without stipules. Flowers nodding, on slen-
der pedicels, with 2 bractlets. Calyx-tube ovoid ; limb 5-lobed.
Corolla nearly bell-shaped, 5-lobed. Stamens 4, inserted near
the base of the corolla, 2 of them longer than the other 2.

218 FOUNDATIONS OF BOTANY

Ovary 3-celled; style thread-like, stigma knobbed; ovules
many in 1 cell, solitary in the 2 others. Fruit nearly globose,
1-seeded.

1. L. borealis, L. TWIN-FLOWER. A beautiful, delicate plant.
Corolla pale pink, very fragrant. Moist woods, in moss, and cold
bogs N.

V. TRIOSTEUM, L.

Coarse, hairy, perennial herbs. Leaves large, those of each
pair somewhat joined at the base, so that the stem appears to
rise through them. Calyx-tube ovoid ; divisions of the limb
leaf-like, lance-linear, persistent. Corolla knobbed at the base,
nearly equally 5-lobed. Ovary usually 3-celled, ripening into
a stone-fruit with 3 nutlets.

1. T. perfoliatum, L. TINKER-WEED, WILD COFFEE, FEVER-
WORT, HORSE-GENTIAN. Stem unbranched, soft-hairy, 2-4 ft. high.
Leaves spatulate-ovate, abruptly narrowed at the base, 4-7 in. long
and 2-4 in. wide, bordered with a fringe of hairs. Flowers dark
brownish-purple. Corolla about \ in. long, sticky-downy. Fruit
ellipsoidal, orange-colored when ripe. Common along fence-rows
and in rocky woods.

VI. LONICERA, L.

Shrubs or woody vines. Leaves simple, usually entire,
those of a pair often appearing as if joined together at the
base, so that the stem seems to rise through them. Calyx-
tube ovoid, 5-toothed. Corolla tubular to bell-shaped, often
knobbed at the base or 2-lipped. Stamens 5. Ovary 2-3-
celled, ovules several in each cell; style slender, stigma
knobbed. Fruit a 1-3-celled, 1-few-seeded berry.*

Stems twining.

1. L. Sullivantii, Gray. YELLOW HONEYSUCKLE. Stem some-
what twining. Leaves oval to obovate, obtuse, entire, green above,
with a bloom beneath, the lower short-petioled, the upper sessile or
joined at the base. Flowers in crowded, terminal whorls, bright
yellow, fragrant. Corolla-tube slender, 1-1 1 in. long, bilabiate,
4-lobed, pubescent within. Stamens and style projecting. On river
banks and hillsides ; often cultivated.*

DICOTYLEDONOUS PLANTS 219

2. L. sempervirens, L. CORAL HONEYSUCKLE, TRUMPET HONEY-
SUCKLE. Stem twining high. Leaves evergreen (in the South),
oval to oblong, obtuse, entire, smooth above, pale and often downy
beneath, the lower petioled, the upper pair nearly semi-orbicular and
joined at the base. Flowering spikes terminal, bearing several
whorls. Corolla about 2 in. long, slender, smooth, the limb short,
nearly equally 5-lobed, scarlet without, bright yellow within. Sta-
mens slightly projecting ; fruit red. On low ground ; often culti-
vated.*

3. L. japonica, Thunb. JAPAN HONEYSUCKLE. Stem twining
high; young branches downy. Leaves ovate to oblong, entire,
smooth above, pale and downy beneath, all short-petioled ; peduncles
axillary, 2-bracted, 2-flowered ; flowers white or pink, fading to yel-
low, 2-lipped, the lips nearly as long as the downy tube. Stamens
and style projecting. Fruit black. Introduced from Japan ; com-
mon in cultivation.*

4. L. Caprifolium, L. EUROPEAN HONEYSUCKLE. A moder-
ately high-climbing shrub. Leaves smooth and deciduous, several
of the upper pairs united at their bases to form a flattish disk or
somewhat cup-shaped leaf. Flowers in a single terminal whorl, very
sweet-scented. Corolla whitish, red, or yellow, 2-lipped, with the
lips recurved. Cultivated from Europe.

More or less upright bushes, not climbing.

5. L. tatarica, L. TARTARIAN HONEYSUCKLE. A branching-
shrub, 5-8 ft. high. Leaves oval or ovate, heart-shaped, shining.
Flowers many, showy, rose-colored. Fruit consisting of 2 red
berries ; somewhat united below at maturity. Cultivated from
Asia.

6. L. ciliata, Muhl. EARLY FLY HONEYSUCKLE. A straggling
bush, 3-5 ft. high. Leaves ovate or oval, slightly heart-shaped, thin,
at first downy beneath. Flowers straw-yellow, on short, slender
peduncles. Corolla-lobes nearly equal ; tube pouched at the base.
Fruit, 2 separate red berries.

VH. DIERVILLA, Tourn.

Low, upright shrubs. Leaves taper-pointed, serrate. Flowers
in loose terminal or axillary clusters or cymes. Calyx with
a limb of 5 linear divisions. Corolla funnel-shaped, almost
regularly 5-lobed. Stamens 5. Ovary slender, 2-celled? ripen-
ing into a 2-valved, many-seeded pod.

220 FOUNDATIONS OF BOTANY

1. D. trifida, Moench. COMMON BUSH HONEYSUCKLE. Bushy,
1-4 ft. high. Leaves ovate or oblong-ovate, petioled. Peduncles
1-3-flowered. Pods tapering to a slender point. Rocks, espe-
cially X.

2. D. japonica, Thunb. WEIGELA. A stout, branching shrub,
3-6 ft. high. Leaves broadly oval, acute at the apex, rounded at
the base, coarsely serrate, rough above, downy beneath, short-peti-
oled. Flowers spreading, funnel-form, rose-color, 1-1 i in. long.
Calyx-lobes deciduous. Corolla downy without, the lobes spreading.
Capsule oblong or spindle-shaped. Seeds with netted wings. Intro-
duced from Japan ; common in cultivation.*

97. VALERIAN ACEJE. VALERIAN FAMILY.

Herbs, rarely shrubs. Leaves opposite, without stipules.
Flowers small, usually irregular, in forking cymes. Calyx-
tube adnate to the ovary. Corolla funnel-shaped, the base
often with a sac or spur. Stamens 1-3 or 5, inserted at the
base of the corolla-tube ; filaments slender, anthers versatile.
Ovary cells 3, two of them not ovule-bearing, the third with a
single ovule hanging from the top ; style thread-like, stigma
blunt or 2-3-lobed. Fruit small, not splitting open.

I. VALERIAN A, L.

Perennial, rarely annual, herbs. Root-leaves crowded ;
stem-leaves opposite or whorled, entire or pinnately cut.
Flowers in corymbed, headed, or panicled cymes. Limb of
the calyx consisting of several plumy bristles. Lobes of
the corolla 5 or rarely 3-4, unequal. Stamens 3. Stigma
knobbed. Fruit flattened, ribbed, 1-celled, 1-seeded.

1. V. edulis, Nutt. An upright, straight-stemmed plant, 1-4 ft.
high. Leaves all thickish and closely fringed with short hairs;
root-leaves linear-spatulate or lanceolate-spatulate, entire ; stem-leaves
pinnately parted, the 3-7 divisions long and narrow. Flowers almost
dioecious, in a long, interrupted panicle. Corolla whitish. Root long
and stout, eaten by Indians. Low ground and wet prairies, especially
N. W.

2. V. officinalis, L. GARDEN VALERIAN. Plant smooth or hairy
below, strong-smelling. Rootstock short. Leaves all pinnate ; root-

DICOTYLEDONOUS PLANTS 221

leaves long-petioled, soon withering; stem-leaves 2-5 in. long,
sessile, the leaflets lanceolate, entire or serrate. Corolla pale
pink. Rootstocks strong-scented, used in medicine. Cultivated
from Europe.

H. VALERIANELLA, Tourn.

Annual herbs; stem forking regularly. Leaves opposite,
entire or dentate. Flowers in crowded, terminal, bracted
cymes. Calyx-limb toothed or wanting. Corolla white or
purplish, funnel-form, 5-lobed. Stamens 3. Style 3-lobed.
Fruit 3-celled, 1-seeded.*

1. V. olitoria, Poll. LAMB LETTUCE. Stem erect, smooth, or
downy at the nodes, many times forked, 9-12 in. high. Basal leaves
tufted, spatulate to obovate, entire, the upper lanceolate, dentate,
sessile. Cymes short-peduncled, bracts linear. Flowers pale blue.
Fruit compressed, oblique. On rich soil in waste places.*

2. V. radiata, Dufr. CORN SALAD. Stem erect, smooth above,
downy below, 2-4 times forked, 8-12 in. high. Lower leaves spatu-
late, entire, the upper lanceolate, clasping at the base, dentate.
Cymes compact ; bracts lanceolate. Flowers white. Fruit ovoid,
downy, furrowed. On damp soil.*

98. CUCURBIT ACE JE. GOURD FAMILY.

Somewhat succulent, tendril-bearing, prostrate or climbing,
herbaceous plants. Leaves alternate, with stipules. Flowers
dioecious or monoecious, often gamopetalous. Calyx-tube ad-
nate to the ovary ; calyx-limb (if present) 5-lobed. Corolla
usually 5-lobed and with its tube more or less united with the
calyx-tube. Stamens perigynous or borne upon the corolla,
the anthers usually joined in long, serpentine ridges. Ovary
3-celled ; stigmas 2 or 3. Fruit generally a pepo (like the
melon, squash, and pumpkin), but sometimes dry. Seeds
commonly large and flat. A large family, mostly of tropical
plants, many with eatable fruit, but some species poisonous.

222 FOUNDATIONS OF BOTANY

I. CUCURBITA, L.

Annual or perennial herbs ; stem trailing or climbing, 2-20
ft. long. Leaves angular-lobed ; tendrils branching. Flowers
monoecious, solitary or in small clusters. Calyx 5-toothed, the
limb deciduous. Corolla bell-shaped, 5-lobed. Staminate flowers
with 3 stamens and no pistil ; pistillate flowers with 1 pistil
and 3 imperfect stamens. Style short; stigmas 3-5, each
2-lobed. Fruit 1-celled, with numerous seeds on the 3 parietal
placentae.*

1. C. Melopepo, L. SUMMER SQUASH. Stem rough-hairy, angled,
2-5 ft. long. Leaves broadly heart-shaped, angularly 3-5-lobed,
rough. Flowers yellow, short-peduncled. Fruit roundish, longitudi-
nally compressed, the margin smooth, wavy, or tubercular. Common
in cultivation.*

2. C. verrucosa, L. CROOKNECK SQUASH. Stem rough-hairy,
angled and striate, 5-10 ft. long. Leaves cordate, deeply 5-lobed,
very rough, long-petioled. Flowers light yellow, long-peduncled.
Fruit clavate, the base often slender and curved, smooth or tubercu-
late, very variable. Common in cultivation.*

II. CUCUMIS, L.

Annual herbs; stems trailing, usually shorter and more
slender than in the preceding genus. Tendrils riot forked.
Leaves varying from entire or nearly so to deeply cut. Sterile
flowers in clusters, fertile ones solitary in the leaf-axils.
Corolla of 5 acute petals, which are but little joined at the
base. Stamens not evidently united. Style short ; stigmas 3,
each 2-lobed. Fruit rather long. Seeds not large, lance-
oblong, not margined.

1. C. sativus, L. CUCUMBER. Leaves somewhat lobed, the
middle lobe largest. Fruit more or less covered when young with
rather brittle, blackish prickles, which fall off as it ripens. Culti-
vated from S. Asia. [Other varieties of the genus Cucumis are the
muskmelon, cantaloupe, and nutmeg melon. Other commonly
cultivated genera are Citrullus, the watermelon, and Lagenaria, the
bottle-gourd. Two wild genera, Echinocyslis, the wild cucumber,
and Sicyos, the star cucumber, which blossom through the summer
and autumn, are common in the Northern States and the Middle
West.]

DICOTYLEDONOUS PLANTS 223

99. CAMPANULACEJE. CAMPANULA FAMILY.

Herbs, with, milky juice. Leaves alternate, without stipules.
Flowers regular, not clustered. Calyx 5-lobed, adnate to the
ovary. Corolla regular, bell-shaped, 5-lobed. Stamens 5,
usually free from the corolla and not coherent. -Style 1,
usually hairy above ; stigmas 2 or more. Fruit a capsule,
2 or more celled, many -seeded.

I. CAMPANULA, Tourn.

Annual, biennial, or perennial herbs. Flowers solitary,
racemed or spiked, regular, blue or white. Calyx 5-lobed
or parted. Corolla wheel-shaped to bell-shaped, 5-lobed.
Stamens 5, free from the corolla, distinct, filaments dilated
at the base. Ovary 3-5-celled, many-ovuled ; style 3-parted.
Capsule short, bearing the persistent calyx-lobes at its apex,
many -seeded, splitting open on the sides.*

1. C. rotundifolia, L. HAREBELL. A slender, smooth, branching
perennial, 5-12 in. high. Root-leaves broadly ovate-heart-shaped,
generally somewhat crenate, soon withering. Stem-leaves varying
from linear to narrowly lanceolate, entire. Pedicels slender, flowers
solitary or somewhat racemed, the buds erect but the fully opened
flower drooping. Calyx-teeth erect, awl-shaped. Corolla bell-shaped,
£-1 in. long, its lobes short and recurved. Rocky hillsides, espe-
cially N.

2. C. aparinoides, Pursh. MARSH BELL-FLOWER. Stem angular,
unbranched, slender, weak and leaning on the grass among which it
usually grows, the angles clothed with minute, backward-pointing
prickles. Leaves lance-linear, nearly entire. Flowers terminal,
about £ in. long, white. Corolla bell-shaped. Wet meadows, in tall
grass.

II. SPECULARIA, Heister.

Annual; stems slender, angled. Leaves entire or toothed.
Flowers axillary, regular, solitary or in small clusters, sessile,
bracted. Calyx-tube slender, 3-5-parted. Corolla wheel-
shaped, 5-lobed. Stamens with the filaments flattened and
shorter than the anthers. Ovary 3-celled, many-ovuled ;
stigmas 3. Fruit a prismatic, 3-celled, many-seeded capsule.*

224

FOUNDATIONS OF BOTANY

1. S. perfoliata, A. DC. SPECULARIA. Stem erect, simple or
branched from the base, angles roughened, 10-20 in. high. Leaves
ovate to lanceolate, acute at the apex, sessile, crenate or entire, the
upper bract-like. Flowers solitary or in pairs. Corolla blue, often
wanting. Capsule cylindrical, smaller above. In waste places.*

100. COMPOSITJE. COMPOSITE FAMILY.

Flowers in a dense head, on a common receptacle, sur-
rounded by an involucre composed of many bracts (Fig. 22),

Fio. 22. — Flower-cluster of Bachelor's Button (Centaurea Cyanus).

DICOTYLKDONors PLANTS

225

with usually 5 stamens inserted on the corolla, the anthers
united into a tube which surrounds the style (Fig. 23, V).
Cal\\ with its tube adnate to the ovary, the limb sometimes
wanting, when present taking the form of scales, bristles, etc.,
known as i><r/>/>//s (Fig. 24, IT, III). Corolla either strap-
shaped (Fig. 25, r) or tubular (Fig. 23, V), in the former case

FIG. 23. — Bachelor's Button.

I, vertical section of the receptacle ; II, style and forked stigma (magnified) ;
III, corolla, united anthers and stigma (magnified) ; IV, pistil (magnified);
pap, pappus ; ak, akene ; V, tubular flower cut vertically (magnified), showing
anther-tube, traversed by the style ; /, lobe of corolla.

often 5-toothed, in the latter usually 5-lobed. Style 2-cleft
above. 'Fruit an akene, often provided with means of trans-
portation (Part II, Ch. XXIX). The largest family of
flowering plants and among the most specialized for insect
pollination. The genera of the northern United States are
divided into two suborders: I. TUBULIFLOR^, corolla of the
perfect flowers tubular and 5-lobed ; II. LIGULIFLOB^E, corollas
all strap-shaped and flowers all perfect,

226

FOUNDATIONS OF BOTANY

pap

anth-

FIG. 24. — Bachelor's Button.

I, a tubular flower (magnified) ; anth, the united anthers ; II, fruit (magnified) ;
III, fruit, vertical section (magnified); IV, a neutral ray-flower;1 V, ring
of anthers.

FIG. 25. — Flower-cluster of Yarrow (Achillea Millefolium), enlarged.

A, head seen from above ; J5, longitudinal section ; re, receptacle ; ch, chaff
i, involucre ; r, ray-flowers ; d, disk-flowers ; c, corolla ; s, stigma.

1 This is not precisely homologous with the ray-flowers of Helianthus and most
rayed Compositse, but is an enlarged and conspicuous tubular flower.

DICOTYLEDONOUS PLANTS 227

I. TUBULIFLORJE.

Corollas some or all of them tubular.
Rays white, pink, or purplish.

Rays many ; akenes flat ; pappus wanting ; low herbs. Bellis, I.

Rays many ; akenes cylindrical or winged, grooved ; pappus

wanting ; tall herbs or shrubby. Chrysanthemum, VIII.

Rays many ; akenes flat ; pappus of an outer row of minute

scales and an inner row of delicate bristles. Erigeron, II.

Rays many ; akenes cylindrical or ribbed ; pappus wanting ;

strong-scented branching herbs. Anthemis, VI.

Rays few. Achillea, VIT.

Rays yellow.

Disk purplish-brown. Rudbeckia, IV.

Disk yellow.

Involucre of 2 rows of bracts, the outer rather leaf-like.

Coreopsis, III.
Involucre of reflexed scales ; pappus of 5-8 scales.

Helenium, V.
Involucre of erect scales ; pappus of abundant soft hairs.

Senecio, IX.

Rays none, but the marginal flowers sterile and their tubular
corollas partly flattened like rays (Fig. 24). Centaurea, X.

Rays none and marginal flowers like the others ; scales of the
involucre overlapping in many rows, prickly-pointed.

Cirsium, XI.

Corollas all strap-shaped.

Corollas blue (rarely pinkish); akenes not beaked.

Cichorium, XIII.
Corollas blue ; akenes beaked. Lactuca, XVIII.

1 The characters in this key are not necessarily true of all species in the genera
referred to, but only of those described below.

228 FOUNDATIONS OF BOTANY

Corollas yellow.

Akenes truncate ; pappus double, of chaff and bristles.

Krigia, XII.

Akenes columnar ; pappus of tawny, rough bristles ; stem

scape-like. Hieracium, XIV.

Akenes spindle-shaped, not beaked; pappus of plumed

bristles. . Leontodon, XV.

Akenes ovoid to spindle-shaped, long-beaked ; pappus white,

soft, and abundant. Taraxacum, XVI.

Akenes nearly as in XVI ; pappus tawny.

Pyrrhopappus, XVII.

Akenes flattened, beaked ; pappus soft, white, the hairs soon
falling off separately ; leafy-stemmed herbs.

Lactuca, XVIII.

Akenes flattened, not beaked ; pappus abundant, soft, white ;
leafy-stemmed, spiny-leaved herbs. Sonchus, XIX.

I. BELLIS, L.

Small herbs. Leaves usually all radical, petioled. Heads
solitary, disk yellow, ray-flowers white or pink ; involucre
bell-shaped, bracts in 1 or 2 rows, green ; receptacle conical.
Ray-flowers many, in a single row, pistillate. Disk-flowers
tubular, perfect, 4-5-toothed ; forks of the style short, thick,
tipped by roughened cones. Fruit flattened, obovate ; pappus
wanting.

1. B. integrifolia, Michx. AMERICAN DAISY. A branching annual
or biennial herb, 4-12 in. high. Upper leaves lanceolate or oblong,
the lower ones obovate-spatulate. Heads borne on slender peduncles;
rays violet-purple. Prairies, especially S.W.

2. B. perennis, L. ENGLISH DAISY, SCOTCH DAISY. A stem-
less perennial. Leaves obovate-spatulate, smooth or hairy. Heads
f-1 in. in diameter, very pretty, the rays delicate. Cultivated
from Europe.

II. ERIGERON, L.

Herbs. Leaves usually sessile. Heads many-flowered, flat
or nearly hemispherical, the rays numerous, narrow, pistillate.
Scales of the involucre narrow and overlapping but little.

DICOTYLEDONOUS PLANTS 229

Akenes flattish, crowned with a single row of hair-like bristles,
or sometimes with shorter bristles or scales outside these.
Disk yellow, rays white, pinkish, or purple.

1. E. annuus, Pers. COMMON FLEABANE. Annual or biennial.
Stem grooved and stout, branching, 2-5 ft. high, with scattered
hairs ; lowest leaves petioled, ovate, coarsely toothed, those higher up
the stem successively narrower, sessile ; heads in a large loose
corymb ; rays short, white or purplish. Fields and waste ground.

2. E. strigosus, Muhl. DAISY FLEABANE. Annual or biennial.
Considerably reserribling the preceding species, but with entire
leaves, smaller and less branched stem, smaller heads, and longer
rays. Fields and pastures.

3. E. bellidifolius, Muhl. ROBIN'S PLANTAIN. Perennial. Soft-
hairy ; stems sometimes throwing out offsets from the base ; simple,
erect, 1-2 ft. high; root-leaves, obovate-obtuse, somewhat serrate;
stem-leaves few, lance-oblong, acute, clasping ; heads rather large,
1—9, on long peduncles, with 50-60 long, rather broad, bluish-purple
or reddish-purple rays. Thickets and moist banks.

4. E. philadelphicus, L. Perennial. Rather hairy ; stems slender,
about 2 ft. high ; root-leaves spatulate and toothed ; stem-leaves
usually entire and strongly clasping, sometimes with a heart-shaped
or eared base ; heads several, small, long-petioled ; rays exceedingly
numerous, thread-like, reddish-purple or flesh-color. In damp soil.

in. COREOPSIS, L.

Annual or perennial herbs. Leaves opposite or the upper
alternate, entire or pinnately divided. Heads radiate, solitary
or corymbed, many -flowered ; bracts in 2 rows of about 8 each,
the inner membranaceous and appressed, the outer narrower
and spreading ; receptacle chaffy. Ray-flowers neutral ; disk-
flowers tubular, perfect. Akenes compressed, oval to oblong,
often winged. Pappus of 2 scales or bristles, or wanting.*

1. C. tinctoria, Nutt. GARDEN COREOPSIS. Annual. Stem erect,
smooth, branched, 2-3 ft. high. Leaves 2—3 times pinnately divided,
the divisions linear, lower leaves petioled, the upper often sessile and
entire. Heads 1-1 1 in. wide, on slender peduncles ; inner bracts
brown with scarious margins, outer bracts very short. Ray-flowers
about 8, yellow with a brown base, 3-lobed at the apex. Akenes
linear. Pappus minute or none. Common in gardens.*

2. C. lanceolata, L. TICKSEED. Perennial; stem slender, erect
or ascending, smooth or slightly downy below, simple, 9-15 in. high.
Leaves opposite, the lower spatulate to elliptical, sometimes lobed,

230 FOUNDATIONS OF BOTANY

on long, hairy-fringed petioles, the upper lanceolate, sessile. Heads
few, on long peduncles ; bracts ovate-lanceolate, the outer narrower.
Ray-flowers 6-10, rays 3-5-lobed, bright yellow. Akenes oval,
broadly winged, warty. Pappus of 2 teeth. On rich, dry soil S.
and E.*

3. C. auriculata, L. RUNNING TICKSEED. Perennial; stem ascend-
ing or decumbent, weak, smooth, nearly simple, 6-15 in. long.
Leaves ovate to oval, entire or with 2-4 small and rounded lobes at
the base, downy, long-petioled. Heads 1-1^ in. wide, few or single ;
outer bracts narrower than the inner. Rays 6-10, mostly 4-toothed
at the apex ; chaff as long as the flowers. Akenes oblong, the wings
narrow and thickened. Pappus of 2 minute teeth. In rich woods.*

IV. RUDBECKIA, L.

Perennial 'or biennial. Leaves alternate, entire or lobed.
Heads radiate, long-peduncled, many-flowered; bracts imbri-
cated in 2-3 series, spreading ; receptacle convex or long-coni-
cal, with concave, chaffy scales. Ray -flowers yellow, neutral ;
disk-flowers purple to brown, perfect. Akenes smooth,
4-angled, truncate. Pappus a few short teeth or wanting.1*

1. R. hirta, L. CONE-FLOWER. Annual or biennial ; stem erect,
rough-hairy, simple or branched, 2-3 ft. high. Leaves lanceolate to
oblong, thick, obscurely serrate, rough-hairy, 3-ribbed, the lower
petioled, the upper sessile. Heads few, long-peduncled ; bracts
rough-hairy, spreading. Ray-flowers 10-20, orange-yellow; disk-
flowers purplish brown. Chaff acute, hairy at the apex. Pappus
none. On dry, open ground.

V. HELENIUM, L.

Annual or perennial. Leaves alternate, forming wings on
the stem. Heads radiate, peduncled, many -flowered ; bracts
in 2 series, the outer linear and spreading, the inner few and
scale-like ; receptacle naked, convex or oblong. Ray-flowers
pistillate and fertile, or neutral, the rays wedge-shaped, 3-5-
lobed ; disk-flowers perfect, tubular, 4-5-lobed. Akenes top-
shaped, hairy, ribbed. Pappus of 4-5 entire, toothed or awned
scales.*

1. H. nudiflorum, Nutt. SNEEZEWEED. Perennial; stem slender,
erect, downy, branched above, 1-2 ft. high. Leaves lanceolate,
entire or slightly toothed, the lower petioled, the upper sessile.

DICOTYLEDONOUS PLANTS 231

Heads numerous. Ray-flowers 10-15, neutral, yellow or yellow and
brown ; disk-flowers purple. Akenes hairy on the ribs ; pappus of
ovate, minutely toothed, awned scales. Common on river banks S.*

VI. ANTHEMIS, L.

Aromatic or ill-scented herbs. Leaves finely pinnately
divided. Heads many-flowered, with ray-flowers. Kays pis-
tillate or neutral. Involucre of many small, dry, close-pressed
scales. Akenes nearly cylindrical, generally ribbed; barely
crowned or naked at the summit.

1. A. Cotula, DC. MAYWEED, DOG-FENNEL. Leaves irregularly
cut into very many narrow segments. Heads small, produced all
summer. Disk yellow. Rays rather short, white, neutral. A low,
offensive-smelling annual weed, by roadsides and in barnyards.

VH. ACHILLEA, L.

Perennial ; leaves alternate, pinnately divided. Heads with
ray -flowers in a terminal corymb ; involucral bracts imbricated
in several series, the outer shorter ; receptacle chaffy. Ray-
flowers white or pink, pistillate and fertile ; disk-flowers per-
fect, tubular, 5-lobed. Akenes oblong, compressed, slightly
margined. Pappus none.*

1. A. Millefolium, L. YARROW. Stems often clustered, erect
from a creeping rootstock, simple, downy or woolly, 1-2 ft. high.
Leaves lanceolate or oblong, the segments finely cut and divided,
smooth or downy, the lower petioled, the upper sessile. Heads
small, numerous, in flat-topped corymbs ; bracts downy. Ray-flowers
4-5, white or pink, rays 3-lobed at the apex. Common in old fields.*

VHI. CHRYSANTHEMUM, Tourn.

Perennials, with toothed, pinnately cut or divided leaves.
Heads nearly as in the Anthemis, except that the ray-flowers
are pistillate.

1. C. Leucanthemum, L. OXEYE DAISY, WHITEWEED, BULL'S-
EYE, SHERIFF PINK. Stem erect, unbranched or nearly so, 1-2 ft.
high; root-leaves oblong-spatulate, petioled, deeply and irregularly
toothed ; stem-leaves sessile and clasping, toothed and cut, the upper-
most ones shading off into bracts. Heads terminal and solitary,

232 FOUNDATIONS OF BOTANY

large and showy, with a yellow disk and many white rays. A trouble-
some but handsome perennial weed. Introduced from Europe,
chiefly E.

2. C. frutescens, L. MARGUERITE. Erect, branching, perennial,
woody below, smooth, and with a pale bloom. Divisions of the
leaves linear, with the uppermost leaves often merely 3-cleft bracts.
Heads long-peduncled, showy, with a yellow disk and large, spread-
ing white rays. Cultivated in greenhouses ; from the Canary Islands.

IX. SENECIO, Tourn.

Annual or perennial ; stems often hollow. Leaves alternate,
entire or pinnately divided. Heads with or without rays, in
terminal corymbs ; bracts mostly in a single row, often with a
few shorter ones at the base ; receptacle naked or pitted. Eay-
flowers yellow or orange, pistillate and fertile when present ;
disk-flowers tubular, perfect. Akenes cylindrical or com-
pressed, not beaked or winged, 5-10-ribbed, downy. Pappus
of numerous, slender, white hairs.*

1. S. tomentosus, Michx. WOOLLY RAGWEED. Perennial ; woolly
throughout ; stem stout, erect, mostly simple, 2-3 ft. high. Lower
leaves ovate to oblong, crenate or entire, obtuse, long-petioled ; stem-
leaves few, elliptical to oblanceolate, serrate or toothed, acute, sessile.
Heads radiate, f in. wide, on slender peduncles; bracts narrow,
becoming smooth. Ray-flowers 12-15, yellow. Akenes hairy. On
damp soil.*

2. S. aureus, L. GOLDEN RAGWEED. Perennial ; stems often
tufted, erect, slender, woolly when young, branched above, 18-30 in.
high. Lower leaves broadly ovate, obtuse at the apex, heart-shaped
at the base, crenate, long-petioled ; stem-leaves lanceolate and often
pinnatifid, the upper small and sessile. Heads radiate, corymbed,
on slender peduncles; ray-flowers 8-12, bright yellow. Akenes
smooth. On wet soil ; very variable.*

3. S. lobatus, Pers. BUTTERWEED. Annual ; stem erect, ridged,
hollow, often woolly when young, and becoming smooth with age,
branched above, 1-3 ft. high. Leaves lyrate-pinnatifid, thin, the
lower petioled, the upper sessile. Heads radiate in a terminal
corymb ; bracts linear, acute. Ray-flowers about 12, yellow.
Akenes slightly rough-hairy on the angles. Pappus rough, longer
than the involucre. Common on low ground.*

DICOTYLEDONOUS PLANTS 233

X. CENTAUREA, L.

Herbs. Leaves entire or cut, often spiny-toothed. Heads
single ; involucre ovoid or globose (Fig. 22) ; bracts closely
overlapping, entire, dry and membranaceous. Corollas all
tubular, oblique or 2-lipped, inflated above ; the outer ones
usually larger and neutral, the inner flowers perfect ; lobes 5,
slender. Akenes flattened. Pappus hairs short, slender, rough.

1. C. Cyanus, L. BACHELOR'S BUTTON. Stem erect, slender,
grooved, 1-2 ft. high, somewhat branched. Leaves acute, sessile,
narrow, entire or few-lobed. Peduncles covered with cottony wool.
Heads £-1 in. in diameter, cobwebby. Ray-like flowers few, large,
bright blue or pink ; those of the disk smaller. Cultivated from
Europe and escaped from gardens.

XI. CIRSIUM, Tourn.

Biennial or perennial; stem erect, simple or branched.
Leaves alternate, prickly, often forming wings on the stem.
Heads discoid, terminal and solitary or corymbed, many-flow-
ered; bracts overlapping in many series, the outer shorter,
usually spine-pointed ; receptacle bristly. Corollas purplish
or nearly white, the tube slender, deeply 5-cleft. Akenes
oblong, 4-angled, smooth or ribbed. Pappus of numerous
simple or plumose bristles.*

1. C. altissimum, Spreng. TALL THISTLE. Perennial or bien-
nial ; stem stout, very leafy, downy or woolly, branched 4-10 ft.
high ; leaves rough-downy above, hoary beneath, fringed with fine
prickles, not forming wings on the stem, the lower petioled and
often pinnately cut, the upper sessile and entire. Heads ovoid, 1 in.
in diameter ; bracts viscid, webby when young, all except the inner
ones tipped with weak and spreading bristles. Flowers light purple.
Common in fields, woods, and waste places.*

2. C. horridulum, Michx. YELLOW THISTLE. Biennial or peren-
nial ; stem erect, stout, woolly when young, becoming smooth, often
purple, branched 1-3 ft. high. Leaves pinnately cut, with very
spiny teeth, mostly sessile and clasping, smooth and green on both
sides. Heads large, surrounded by a whorl of linear-oblong, comb-
like leaves ; involucral bracts linear, ciliate, not spine-tipped. Flowers
purple or yellowish. On sandy soil E. and S.*

234 FOUNDATIONS OF BOTANY

II. LIGULIFLORJE.
XH. KRIGIA, Schreber.

Small, annual or perennial herb. Leaves mostly radical,
toothed or lyrate. Heads several-many-flowered; scales of
the involucre about 2-rowed, thin. Akenes short, truncate.
Pappus in 2 rows, the outer one of thin, blunt, chaffy scales,
the inner one of slender bristles. Corollas yellow.

1. K. virginica, Willd. Annual ; scapes usually 2-5 from one
root, slender. Leaves mostly lyrate, smooth and with a bloom, the
earlier ones rounded or spatulate. Scales of the involucre linear-
lanceolate, nearly equal, spreading. Akenes top-shaped, reddish-
brown, crowned with 5 wedge-obovate scales and 5 rough white
bristles.

2. K. Dandelion, Nutt. Perennial, from slender tuber-bearing
roots. Scapes leafless, 6-18 in. high. Leaves entire or nearly so,
varying from spatulate-oblong to linear-lanceolate. Akenes more
slender than in No. 1. Pappus consisting of 10-15 small, oblong,
chaffy scales and 15-20 bristles. In moist ground, especially S.

3. K. amplexicaulis, Nutt. Stem 12-18 in. high, often 2-3 from
the same root, mostly 2-forked or 3-forked at the summit. Root-
leaves 3-6 in. long, lanceolate, entire, toothed or rarely pinnately
cut, clasping at the base ; stem-leaves 1-3. Akenes and pappus
about as in No. 2. Moist banks.

XIII. CICHORIUM, L.

Perennial herbs with spreading branches ; juice milky.
Leaves radical and alternate, toothed or pinnately cut. Heads
axillary ; involucre cylindrical, bracts in 2 rows, the inner
row erect, coherent at the base, the outer shorter ; receptacle
flattish. Corollas blue, pale pink, or yellow. Upper part of
the style and its slender arms hairy. Akenes crowded on the
hardened receptacle, firmly covered by the stiff involucre,
obovoid or top-shaped, not beaked. Pappus 1 or 2 rows of
short scales.

1. C. Intybus, L. CHICORY, BLUE DANDELION, BLUE SAILORS.
Root very long, stout, and fleshy. Stem 1-3 ft. high, angled and
grooved ; branches straight and stiff. Root-leaves and lower stem-
leaves runcinate ; upper stem-leaves oblong or lanceolate, clasping,

DICOTYLEDONOUS PLANTS 235

those of the branches reduced to bracts. Flowers very showy,
usually bright blue, rarely pinkish-white. Introduced from Europe ;
a troublesome weed in grass-lands and common in waste places,
particularly in New England.

XIV. HIERACIUM, L.

Perennial herbs, often covered with glandular or star-shaped
hairs ; juice milky. Leaves alternate. Heads solitary, or in
corymbs or panicles ; bracts of the involucre many, overlap-
ping, unequal ; receptacle flattish, naked, pitted. Corollas
yellow, rarely orange; arms of the style slender and upper
part of the style hairy. Akenes angled or grooved, not beaked.
Pappus hairs in a single row, simple, stiff, tawny, or brownish,
brittle.

1. H. venosum, L. RATTLESNAKE WEED. Stem scape-like,
usually leafless or nearly so, smooth, 1-2 ft. high. Root-leaves 2-5
in. long, obovate or ovate-oblong, generally purple-veined. Heads
rather large, yellow, in a loose panicled corymb. Dry hills and
roadsides, and in pine woods E.

XV. LEONTODON, L.

Perennial, scape-bearing herbs; juice milky. Leaves all
radical, toothed or pinnatifid, often runcinate. Heads on
simple or branched scapes, yellow; bracts of the involucre
many, in several rows, the anther smaller ; receptacle flat,
naked. Arms of the style linear, obtuse, hairy. Akenes cylin-
drical, grooved, transversely wrinkled ; beak short ; pappus
hairs stiff, in 1 or 2 rows.

1. L. autumnalis, L. Scape usually branching, 5-15 in. high,
bracted ; peduncles enlarged above. Rootstock truncate. Heads
l£-l in. or more in diameter ; involucre top-shaped or bell-shaped.
Pappus of a single row of tawny hairs. Fields and roadsides,
especially N. E. Introduced from Europe.

XVI. TARAXACUM, Haller.

Stemless, perennial or biennial herbs. Leaves in a flattish
tuft, pinnately cut or runcinate (Fig. 38). Head many-
flowered, large, solitary, yellow, borne on a hollow scape, which

236 FOUNDATIONS OF BOTANY

is short at first but lengthens after flowering. Involucre com-
posed of a single row of long, erect, inner scales and a set of
much shorter ones outside and at the base of the former ones.
Akenes cylindrical or spindle-shaped, with 4-5 rough ribs, the
apex tapering into a bristle-like beak which bears a short,
broadly conical tuft of soft white hairs.

1. T. officinale, Weber. DANDELION. Outer involucre reflexed ;
inner involucre closing over the head, after the flowers are withered,
and remaining shut for some days, then opening and allowing the
akenes to form a globular head. Root stout, bitter, medicinal.
Young leaves eaten as a pot-herb ("greens") in spring — the plant
often cultivated for the leaves by market-gardeners.

XVII. PYRRHOPAPPUS, DC.

Annual or biennial ; stem erect, leafy below, nearly naked
above, smooth. Leaves oblong, toothed or pinnatifid. Heads
large, long-peduncled ; involucre cylindrical or spreading, the
inner row of bracts erect, united at the base, the outer rows
shorter and spreading; receptacle naked. Flowers yellow;
rays truncate, 5-toothed at the apex. Akenes oblong, 5-ribbed,
narrowed above into a long and slender beak ; pappus soft,
tawny, with a short, soft-hairy ring at the base.*

1. P. carolinianus, DC. FALSE DANDELION. Annual or bien-
nial ; stem glabrous, furrowed, branched above, 2-3 ft. high. Lower
leaves lanceolate to oblong, entire, toothed or pinnatifid, narrowed
into a margined petiole, the upper sessile, bract-like, entire. Heads
few, long-peduncled, peduncles and involucre sometimes finely
downy; inner bracts calloused at the apex, the outer awl-shaped
and spreading. Akenes much shorter than the thread-like beak.
Common in fields.*

XVIII. LACTUCA, Tourn.

Annual, biennial, or perennial ; stems leafy. Leaves entire
to pinnately cut. Heads panicled; involucre cylindrical,
bracts unequal, overlapping in 2 or more rows, the outer
shorter ; receptacle naked. Flowers blue, yellow, or white ;
rays truncate, 5-toothed at the apex. Akenes compressed,
ribbed, the apex contracted into a slender beak, which is
enlarged into a disk bearing the soft, hairy, white or tawny
pappus,*

DICOTYLEDONOUS PLANTS 237

1. L. canadensis, L. WILD LETTUCE. Biennial ; stem erect,
smooth, hollow, branched above, 3-10 ft. high. Leaves lanceolate
to spatulate, pale beneath, the lower petioled and pinnately cut, the
upper sessile, clasping, and nearly entire. Heads numerous, about
20-flowered. Flowers yellow ; akenes oval, flat, 1-ribbed on each
side, minutely roughened, about as long as the beak. Pappus
white. In waste places.*

2. L. acuminata, Gray. BLUE LETTUCE. Stem very leafy,
smooth, paniculately branched above, 3—6 ft. high. Leaves ovate to
lanceolate, taper-pointed, often hairy beneath, the lower on winged
petioles and often sinuate-lobed, the upper sessile. Heads racemed,
on divergent and bracted peduncles. Flowers blue. Akenes slightly
compressed, beak very short. Pappus white. In waste places.*

XIX. SONCHUS, L.

Annual or perennial. Leaves mostly toothed or pinnately
cut, prickly margined. Heads in corymbs or panicles ; bracts
in several series, the outer shorter ; receptacle naked. Flowers
yellow, rays truncate, 5-toothed at the apex. Akenes oval to
oblong, compressed, ribbed, truncate at the apex. Pappus of
numerous soft white hairs.*

1. S. oleraceus, L. Sow THISTLE. Annual; stem erect, branched,
smooth, 2-6 ft. high. Leaves spiny-toothed, the lower long-petioled,
very irregularly cut or pinnatifid, the upper clasping by an eared
base. Involucre downy when young. Akenes channeled and trans-
versely wrinkled. In waste places on very rich soil.*

2. S. asper, Vill. SPINY Sow THISTLE. Annual; stem erect,
smooth, branched but little, 2-6 ft. high. Leaves undivided, spatu-
late to oblanceolate, fringed with spiny teeth, the lower narrowed
into a petiole, the upper clasping by an eared base, the ears rounded.
Heads numerous ; involucre glabrous. Akenes flattened, margined,
3-nerved on each side, smooth. In waste places.*

GLOSSARY

OF TECHNICAL TERMS USED ONLY IN THE FLORA

Abortive, imperfectly developed.

Appressed, lying flat throughout its
length, used of such parts as
bracts.

Awl-shaped, narrow and tapering
to a point.

Awned, having a bristle-like ap-
pendage.

Awnless, not awned.

Capitate, (1) having a round head

like the stigma of a primrose ;

(2) growing in heads.
Carpellary, relating to a carpel.
Chaff, small membranous scales,

such as are found on disks of

Composite.
Clasping, partly surrounding the

stem, said of the bases of leaves.
Claw, the narrowed base of a petal.
Cleft, cut halfway down.
Coated (bulbs), those with scales

which completely cover them, as

in the onion.
Cone, the fruit of pines, etc., with

ovule-bearing scales.
Connate, united, said of opposite

leaves which appear as if grown

together at their bases.
Cordate, heart-shaped.
Corm, a bulb-like, fleshy stem or

base of a stem.

Crown, an inner appendage to a
petal or to the throat of the co-
rolla.

Deciduous, falling as petals do after
blossoming, or as leaves of most
trees except evergreens do.

Declined, directed obliquely.

Decumbent, reclining, but with the
summit somewhat erect.

Dehiscent, splitting into definite
parts.

Diffuse, spreading widely or loosely.

Disk, (1) an outgrowth of the re-
ceptacle within the calyx or
within the corolla and stamens ;
(2) the central part of the head
(all but the rays) in Composite.

Dissected, deeply divided or cut
into many segments.

Drupe, a stone-fruit such as a peach
or a plum.

Equitant, leaves astride of those
within them, thus appearing in a
cross-section like the diagram,

Even-pinnate, abruptly pinnate,*, e. ,
with no leaflet at the end.

Fascicle, a close cluster or bundle
of flowers, leaves, stems, or roots.

240

FOUNDATIONS OF BOTANY

Fertile, capable of producing fruit ;

fertile flowers, those which have

pistils.

Filiform, thread-shaped.
Fleshy, succulent, thick and full of

sap.
Funiculus, the little stalk which

connects a seed or ovule with the

placenta.

Gland, (1) a structure which secretes
something, as the knobs on the
hairs of sundew ; (2) any knob
or swelling.

Herbaceous, with no stem above-
ground which lives through the
winter, not woody or shrubby.

Indefinite, too many to be easily
counted.

Indehiscent, not splitting open reg-
ularly.

Involucrate, provided with an in-
volucre.

Keel, the two anterior and united
petals of a papilionaceous corolla.

Key, a winged fruit like that of the
ash or maple.

Limb, the border or spreading part
of a gamopetalous calyx or co-
rolla.

Lobed, having divisions, especially
rounded ones.

Nerved, having simple or un-
branched veins or slender ribs.

Ob, in composition, signifies in-
versely, as obcordate, inversely
heart-shaped.

Odd-pinnate, pinnate with a single
leaflet at the end of the midrib.

Palate, a projection in the throat
of a corolla.

Papilionaceous, butterfly - shaped,
like the corolla of the sweet pea.

Papillose, covered with papillae or
minute projections, like the
human tongue.

Pappus, tufts of hair or other ob-
jects, representing the limb of the
calyx in Composttce.

Perfoliate, with the stem appar-
ently growing up through a leaf,
as in some honeysuckles.

Persistent, not deciduous.

Pinnatifid, pinnately cleft.

Pistillate, having pistils but not
stamens.

Pubescent, clothed with soft hair,
downy.

Punctate, marked with dots, de-
pressions, or translucent glands.

Kadical, arising from the root or a
very short stem at its summit, as
the leaves of the dandelion.

Reflexed, bent or turned abruptly
downward or backward.

Root-parasite, a plant parasitic on
the roots of another.

Sagittate, arrow-shaped.

Scape, a leafless flower-stalk aris-
ing from the ground, as in the
dandelion and cyclamen.

Scarious, thin, dry, and membra-
nous, not green.

Sessile, without a stalk.

Simple (stem), unbranched.

GLOSSARY

241

Spadix, a spike with a fleshy axis,
like that of the Indian turnip or
the "caJla."

Spathe, a large bract which encloses
a flower-cluster, often a spadix.

Staminate, having stamens only.

Standard, the posterior petal of a
papilionaceous corolla.

Sterile, (1) barren, as a flower with-
out a pistil or an antherless sta-
men ; (2) staminate or male, said
of flowers.

Striate, marked with fine longitudi-
nal parallel lines.

Sub- (in composition), somewhat, as
subglobose.

Subtend, to extend beneath, as a
bract in the axil of which a
flower is borne.

Succulent, fleshy or juicy.

Three-ranked, with three vertical
rows on a stem or axis.

Throat, the top of the tubular part

of a gamopetalous corolla.
Truncate, appearing as if cut

squarely off, as the leaves of the

tulip-tree.
Tubercled, covered with warty

growths.
Tubercular, having tubercles, or

like a tubercle.
Two-ranked, with three vertical

rows on a stem or axis.

Utricle, a small bladdery ovary-
wall.

Versatile, turning freely on its sup-
port, as an anther on its filament.

Whorled, arranged hi a circle
around an axis, as the leaves of
some lilies.

Wings, the side-petals of a papilio-
naceous flower.

IlffDEX

Abies, 17.
Abutilon, 148.
Acanthacese, 210.
Acanthus Family, 210.
Acer, 141.
Aceracese, 140, 141.
Achillea, 281.
Aconitum, 80.
Acorus, 25.
Actsea, 79.
Adder' s-tongue, 36.
Adlumia, 92.
^Esculus, 142.
Agrostemma, 73.
Aizoaceae, 69.
Alder, 55, 139.
Alfalfa, 124.
Alisma, 21.
Alismacese, 21.
Alleghany Vine, 92.
Allium, 34.
Alnus, 54, 55.
Aluni Root, 103.
Alyssum, 98, 99.
Amaryllidacese, 42.
Amaryllis Family, 42.
Amelanchier, 110.
American Aspen, 47.
Amianthium, 32, 33.
Amorpha, 126.
Ampelopsis, 146.
Amsonia, 178, 179.
Anagallis, 174.
Anarcardiaceae, 137.

Andromeda, 168.
Anemone, 80, 81.
Anemone, Rue, 82.
Anemonella, 82.
Angiosperms, 20.
Anonaceae, 88.
Anthemis, 231.
Antirrhinum, 203.
Apetalous Division, 6.
Apkyllon, 208.
Apocynacese, 178.
Apocynum, 179, 180.
Apple, 109.
Aquifoliacese, 138.
Aquilegia, 79.
Arabis, 98.
Aracese, 23.
Aralia, 157, 158.
Araliaceae, 157.
Arbor Vitse, 18.
Arbutus, Trailing, 169.
Arctostaphylos, 169.
Arissema, 24, 25.
Aristolochia, 65.
Aristolochiaceae, 64, 65.
Arrowhead, 22.
Arrowwood, 216, 217.
Arum Family, 23.
Asarum, 65.

Asclepiadacese, 180, 181.
Asclepias, 181, 182.
Ash, 134, 175.
Ash, Mountain, 109.
Asimina, 88.

243

244

FOUNDATIONS OF BOTANY

Asparagus, 38.
Asp, Quaking, 47.
Aspen, American, 47.
Astragalus, 127, 128.
Atamasco Lily, 43.
Avens, 114, 115.

Babies' Toes, 134.
Bachelor's Button, 233.
Bald Cypress, 18.
Balsam, 143.
Balsam Family, 143.
Balsam Fir, 17.
Balsaminacese, 143.
Bamboo-vine, 42.
Baneberry, 79.
Baptisia, 122.
Barberry, 84.
Barberry Family, 84.
Barren Strawberry, 113.
Basswood, 147.
Bastard Toad-flax, 64.
Bay berry, 49.
Bayberry Family, 49.
Beaked Hazelnut, 53.
Bearberry, 169.
Bedstraw, 215.
Beech, 56.
Beech Family, 55.
Beggar's Lice, 190.
Begonia, 152, 153, 154.
Begoniacese, 152.
Begonia Family, 152.
Bell Flower, 223.
Bell Flower Family, 223.
Bellis, 228.
Bellwort, 33.
Benjamin, 41.
Berberidacese, 84.
Berberis, 84, 85.
Berchemia, 144.

Betula, 53, 54.
Betulacese, 61.
Bignonia, 206.
Bignoniacese, 206.
Bignonia Family, 206.
Bindweed, 184.
Birch, 53, 54.
Birch Family, 61.
Bird's Pepper, 94.
Bishop's Cap, 103.
Bitter Cress, 97.
Bittersweet, 139, 199.
Black Alder, 139.
Blackberry, 112.
Black Gum, 164.
Black Haw, 217.
Black Walnut, 50.
Bladder-nut, 140.
Bladder-nut Family, 140.
Bladderwort, 209, 210.
Bladderwort Family, 209.
Bleeding Heart, 92.
Bloodroot, 90.
Blue Beech, 52.
Bluebell, 187.
Bluebells, 190.
Blueberry, 170.
Blue Cohosh, 85.
Blue Dandelion, 234.
Blue Devils, 191.
Blue Flag, 45.
Blue Sailors, 234.
Blue Thistle, 191.
Bluets, 213.
Blue Valerian, 187.
Blueweed, 191.
Borage Family, 188.
Borraginaceae, 188.
Boston Ivy, 146.
Bouvardia, 214.
Box Elder, 141.

INDEX

245

Brassica, 95, 96.
Breeches Flower, 91.
Bridal Wreath, 108.
Brooklime, 204.
Broom-rape Family, 208.
Broussonetia, 62.
Brunella, 196.
Buck-bean, 178.
Buckeye, 142.
Buckeye Family, 142.
Buckthorn, 144.
Buckthorn Family, 143.
Buckwheat, 67.
Buckwheat Family, 66.
Buffalo Apple, 128.
Buffalo Pea, 128.
Bull Nut, 51.
Bull's-eye, 231.
Bulrush, 24.
Bunch-berry, 163.
Bur, Buffalo, 200.
Bur, Sand, 200.
Butter and Eggs, 203.
Buttercup, 83.
Buttercup Family, 77, li
Butternut, 50.
Butterweed, 232.
Button Snakeroot, 159.
Buttonwood, 105.

Cactacese, 154.
Cactus Family, 154.
Calamus, 25.
Calico Bush, 168.
Callicarpa, 193.
Caltha, 78.
Calycanthacese, 87.
Calycanthus, 87, 88.
Calycanthus Family, 87.
Calystegia, 183, 184.
Camassia, 36, 37.

Campanula, 223.
Campanulacese, 223.
Campanula Family, 223.
Cancer Root, 208.
Cannabis, 62.
Cantaloupe, 222.
Caper Family, 99.
Capparidacese, 99.
Caprifoliacese, 215.
Capsella, 98.
Caraway, 160.
Cardamine, 97.
Carnation, 75.
Carpenter-weed, 196.
Carpet-weed, 70.
Carpinus, 51, 52.
Carrion Flower, 41.
Carrot, 162.
Carum, 160.
. Carya, 50, 51.

Caryophyllaceae, 71, 72.
Castanea, 56.
Castilleia, 205.
Catalpa, 207.
Cat-brier, 42.
Catchfly, 74.
Catnip, 195.
Cat-tail, 20.
Cat-tail Family, 20.
Caulophyllum, 86.
Ceanothus, 144, 145.
Cedar, 18, 19.
Celandine, 90.
Celastraceae, 139.
Celastrus, 139.
Celtis, 60.
Centaurea, 233.
Cerastium, 72.
Cercis, 120.
Cereus, 155.
Chamselirium, 32.

246

FOUNDATIONS OF BOTANY

Charlock, 95, 96.
Cheeses, 148.
Chelidonium, 90.
Chenopodiaceae, 68.
Chenopodium, 68, 69.
Cherry, 117.
Chestnut, 56.
Chickweed, 72.
Chickweed Wintergreen, 173.
Chicory, 234.
Chimaphila, 164, 165.
Chinese Sacred Lily, 43.
Chinquapin, 56.
Chinquapin, Water, 76.
Chionanthus, 176, 177.
Chocolate Root, 115.
Chokeberry, 109.
Chokecherry, 117.
Chokepear, 109.
Chrysanthemum, 231, 232.
Cichorium, 234.
Cinquefoil, 114.
Circsea, 157.
Cirsium, 233.
Citrullus, 222.
Citrus, 133.
Cladrastis, 121.
Claytonia, 70.
Clematis, 82.
Cleome, 100.
Clove Pink, 75.
Clover, 124, 125.
Cochlearia, 95.
Coffee Tree, 121.
Cohosh, 85.
Columbine, 79.
Comandra, 64.
Comfrey, 189.
Commelina, 27.
Commelinacese, 26.
Composites, 224-228.

Composite Family, 224-228.
Cone-flower, 230.
Coniferae, 13.
Conopholis, 208.
Convallaria, 40.
Convolvulacese, 183.
Convolvulus, 184.
Convolvulus Family, 183.
Coptis, 79.
Coreopsis, 229, 230.
Cornaceae, 162,
Corn Cockle, 73.
Cornel, 163.
Corn Gromwell, 191.
Corn Salad, 221.
Cornus, 162, 163.
Corydalis, 93.
Corylus, 52, 53.
Cotton wood, 48.
Cow Lily, 77.
Cow Parsnip, 162.
Cowslip, 78.
Crab Apple, 109.
Cranberry, 171.
Cranberry Tree, 216.
Cranesbill, 130.
Cratsegus, 110, 111.
Creepers, 183.
Creeping Charley, 195.
Cress, 97.
Crinkle Root, 97.
Crocus, 45.
Cross-vine, 206.
Crowfoot, 83.
Crowfoot Family, 77, 78.
Crown Imperial, 35.
Crown of Thorns, 136.
Crow's Foot, 97.
Crow-victuals, 195.
Cruciferse, 93, 94.
Cucumber, 222.

INDEX

247

Cucumis, 222.
Cucurbita, 222.
Cucurbitacese, 221.
Currant, 104.
Cuscuta, 183.
Cydouia, 108.
Cynoglossum, 189.
Cyperaceae, 23.
Cypress, 18, 137.
Cypress Vine, 184.
Cypripediura, 46.
Cytisus, 123.

Daffodil, 43.
Daffy, 43.
Daisy, 228, 231.
Dakota Turnip, 126.
Dandelion, 236.
Datura, 200, 201.
Daucus, 162.
Dayflower, Virginia, 27.
Day-lily, 34.
Dead Nettle, 196.
Deerberry, 171.
Delphinium, 80.
Dentaria, 97.
Deptford Pink, 75.
Desmanthus, 119, 120.
Deutzia, 104.
Devil's Bit, 32.
Dewberry, 112.
Dianthera, 211.
Dianthus, 75.
Dicentra, 91, 92.
Dicotyledonous Plants, 47.
Diervilla, 219, 220.
Diospyros, 174.
Dock, 66, 67.
Dodecatheon, 171, 172.
Dogbane, 180.
Dogbane Family, 178.

Dogberry, 109.
Dog-brier, 42.
Dog-bur, 189.
Dog-fennel, 231.
Dog's-tooth Violet, 36.
Dogwood, 163.
Dogwood Family, 162.
Dogwood, Poison, 138.
Dragon Eoot, 25.
Dutchman's Breeches, 91.
Dutchman's Pipe, 65.
Dutchman's Pipe Family, 64, 65.

Ear Drops, 92.
Easter-flower, 43.
Ebenacese, 174.
Ebony Family, 174.
Echinocystis, 222.
Echinospermum, 189, 190.
Echium, 191.
Elder, 215, 216.
Elder, Wild, 157.
Elm, 60.
Elm Family, 59.
Enchanter's Nightshade, 157.
English Ivy, 157.
English Walnut, 50.
Epigaea, 169.
Ericaceae, 166, 167.
Erigenia, 159, 160.
Erigeron, 228, 229.
Eryngium, 158, 159.
Erythronium, 36.
Eschscholtzia, 90.
Euonymus, 139, 140.
Euphorbia, 136, 137.
Euphorbiaceae, 135.
Eutoca, 188.

Evening Primrose Family, 156.
Eyebright, 213.

248

FOUNDATIONS OF BOTANY

Fagacese, 55.
Fagus, 55, 56.
Fairycup, 103.
False Buckwheat, 67.
False Dandelion, 236.
False Indigo, 126.
False Mitre-wort, 102.
False Spikenard, 38.
Farkleberry, 171.
Feverwort, 218.
Field Garlic, 34.
Figwort Family, 201, 202.
Fir, 17.
Fire Pink, 74.
Flag, 45, 46.
Flax, 133.
Flax Family, 132.
Fleabane, 229.
Fleur-de-lis, 45, 46.
Flowering Maple, 148.
Flowering Moss, 186.
Fly Poison, 33.
Forget-me-not, 190, 191.
Forsytkia, 176.
Fragaria, 113.
Fraxinus, 175.
French Mulberry, 193.
Fringe Cap, 103.
Fringe Tree, 177.
Fritillaria, 35.
Fuchsia, 156.

Galium, 214, 215.
Garden Columbine, 79.
Garden Sage, 198.
Garget Root, 69.
Garlic, 34.

Gaylussacia, 169, 170.
Gentianacese, 177.
Gentian Family, 177.
Geraniacese, 129, 130.

Geranium, 130, 131.
Geranium Family, 129, 130.
Geum, 114, 115.
Gill-over-the-ground, 195.
Gillyflower, 99.
Ginseng Family, 157.
Gleditschia, 121.
Golden Alexanders, 161.
Golden Chain, 123.
Gold Thread, 79.
Gooseberry, 104.
Goosefoot, 69.
Goosefoot Family, 68.
Goose Grass, 214.
Gourd Family, 221.
Graminese, 23.
Grape, 145, 146.
Grape Family, 145.
Grass Family, 23.
Grass Pink, 75.
Gratiola, 204.
Graveyard Moss, 137.
Green-brier, 42.
Green Dragon, 25.
Gromwell, Corn, 191.
Ground Ivy, 195.
Ground Pink, 186.
Ground Plum, 128.
Guinea-hen Flower, 35.
Gum, Black, 164.
Gymnocladus, 120, 121.
Gymnosperms, 13.
Gypsy Weed, 205.

Hackberry, 60.
Hackmatack, 18.
Harbinger of Spring, 160.
Hardback, 108.
Harebell, 223.
Haw, 110, ,111, 217.
Hazelnut, 52, 53.

INDEX

249

Heal-all, 196.
Heart's-ease, 151.
Heath Family, 166, 167.
Hedge Mustard, 95.
Helenium, 230.
Heliotrope, 189.
Heliotropium, 189.
Hellebore, White, 32.
Hemerocallis, 33, 34.
Hemlock, 17.
Hemp, 62,
Hen-bit, 196.
Hepatica, 81.
Heracleum, 161, 162.
Herb Robert, 130.
Heuchera, 103.
Hickory, 51.
Hieracium, 235.
High-bush Cranberry, 216.
Hippocastanacese, 142.
Hobble-bush, 216.
Holly, 138, 139.
Holly Family, 138.
Honey Locust,. 121.
Honeysuckle, 167, 218-220.
Honeysuckle Family, 215.
Hop Clover, 125.
Hop-tree, 134.
Horehound, 195.
Hornbeam, 52.
Horse-brier, 42.
Horse-chestnut, 142.
Horse-gentian, 218.
Horse Nettle, 199.
Horse-radish, 95.
Hound's-tongue, 189.
Houstonia, 213.
Hoy a, 183.

Huckleberry, 170, 171.
Hyacinth, 37.
Hyacinthus, 37.

Hydrophyllacese, 187.
Hydrophyllum, 187, 188.
Hypericacese, 148.
Hypericum, 149.
Hypoxis, 43.

Ice Plant, 69.
Ice-plant Family, 69.
Ilex, 138, 139.
Impatiens, 143.
Indian Chief, 172.
Indian Cress Family, 132.
Indian Hemp, 180.
Indian Paint, 191.
Indian Pink, 205.
Indian Pipe, 166.
Indian Poke, 32.
Indian Turnip, 25.
Indigo, 122.
Indigo, False, 126.
Innocence, 213.
Ipomoea, 184, 185.
Iridacese, 45.
Iris, 45, 46.
Iris Family, 45.
Irish Potato, 200.
Iron Wood, 52.
Isopyrum, 78.
Ivy, 138.

Jack-in-the-pulpit, 25.
Jacob's Ladder, 39, 187, 203.
Japanese Ivy, 146.
Jatropha, 137.
Jerusalem Oak, 69.
Jewel Weed, 143.
Jimson Weed, 201.
Johnny-jump-up, 151.
Jointed Charlock, 96.
Juglandacese, 49, 50.
Juglans, 50.

250

FOUNDATIONS OF BOTANY

Juncacese, 29.
Juneberry, 110.
Juniper, 19.
Juniperus, 19.

Kalmia, 168.
Kicking Colt, 143.
King Nut, 51.
Kinnikinnik, 163.
Knawel, 73.
Knot-grass, 67.
Krigia, 234.

Labiatse, 193, 194.
Laburnum, 123.
Lactuca, 236, 237.
Ladies' Eardrop, 156.
Lady's-delight, 151.
Lady's-slipper, 46, 143.
Lady's Tresses, 46.
Lagenaria, 222.
Lamb Lettuce, 221.
Lamium, 196.
Larch, 18.
Larix, 17, 18.
Larkspur, 80.
Lathyrus, 129.
Lauracese, 88, 89.
Laurel, 168, 169.
Laurel Family, 88, 89.
Leather Flower, 82.
LeguminossB, 117-119.
Lemon, 133.
Lentibulariacese, 209.
Leontodon, 235.
Leonurus, 196, 197.
Lepidium, 94.
Lettuce, 237.
Lever-wood, 52.
Liguliflorse, 234.
Ligustrum, 177.

Lilac, 176.
Liliacese, 29.
Lilium, 35.
Lily, 34, 35.
Lily Family, 29.
Lily-of-the-valley, 40.
Lime, 133.
Linacese, 132.
Linaria, 202, 203.
Linden, 147.

Linden Family, 146, 147.
Lindera, 89.
Linnsea, 217, 218.
Linum, 132, 133.
Liriodendron, 87.
Lithospermum, 191.
Live Oak, 58.
Liver-berry, 39.
Liverleaf, 81.
Liverwort, 81.
Lobularia, 98, 99.
Locust, 121, 127.
London Pride, 74.
Lonicera, 218, 219.
Loosestrife, 173.
Loranthacese, 63.
Lotus, 76.
Lousewort, 206.
Lungwort, 190.
Lupinus, 123.
Lychnis, 74.
Lycium, 199.
Lycopersicum, 200.
Lysimachia, 173.

Madura, 61, 62.
Madder Family, 212, 213.
Magnolia, 86.
Magnoliacese, 85, 86.
Magnolia Family, 85, 86.
Maianthemum, 39.

INDEX

251

Mallow, 148.
Mallow Family, 147, 148.
Malva, 148.
Malvaceee, 147, 148.
Maple, 141.

Maple Family, 140, 141.
Marguerite, 232.
Marigold, Marsh, 78.
Marrubium, 195.
Marsh Bell-flower, 223.
Marsh Marigold, 78.
Marsh Trefoil, 178.
Matrimony Vine, 199.
Matthiola, 99.
May-apple, 85.
Mayflower, 102, 169.
Mayweed, 231.
May Wings, 134.
Meadow Buttercup, 78.
Meadow Garlic, 34,
Meadow Lily, 35.
Meadow Parsnip, 161.
Meadow Rue, 84.
Medicago, 124.
Medick, 124.
Melilotus, 124.
Melon, 221.
Menyanthes, 178.
Mercury, 138.
Mertensia, 190.
Mignonette, 100.
Mignonette Family, 100.
Milkweed, 181, 182.
Milkweed Family, 180, 18
Mint Family, 193, 194.
Mistletoe, 64.
Mistletoe Family, 63.
Mitchella, 214.
Mitella, 102.
Mitre-wort, 102.
Mollugo, 70.

Monkshood, 80.
Monocotyledonous Plants, 20.
Monotropa, 166.
Moracese, 61.
Morning-glory, 184, 185.
Morning-glory Family, 183.
Morus, 61.
Moss Pink, 186.
Motherwort, 197.
Mountain Ash, 109.
Mountain Fringe, 92.
Mouse-ear Chickweed, 72.
Mulberry, 61, 62, 111.
Mulberry Family, 61.
Mulberry, French, 193.
Mulberry, Mexican, 193.
Mullein, Moth, 202.
Mullein Pink, 74.
Muskmelon, 222.
Mustard, 95, 96.
Mustard Family, 93, 94.
Myosotis, 190, 191.
Myrica, 49.
Myricacese, 49.

Narcissus, 43.
Nasturtium, 96, 132.
Nelumbo, 76.
Nepeta, 195.
Nerium, 180.
Nettle, 63.

Nettle Family, 62, 63.
New Jersey Tea, 145.
Nightshade, 199.
Nightshade Family, 198.
Ninebark, 107.
Noble Liverwort, 81.
None-so-pretty, 74.
Nonesuch, 124.
Nuphar, 76, 77.
Nutmeg Melon, 222.

252

FOUNDATIONS OF BOTANY

Nymphaea, 76.
Nymphseaceae, 75.
Nyssa, 164.

Oak, 57, 58, 59.
Oakesia, 33.
Obolaria, 177, 178.
(Enothera, 156.
(Enotheracese, 156.
Oleacese, 175.
Oleander, 180.
Olive Family, 176.
Onion, 34.
Opuntia, 154, 155.
Orange, 133.
Orange Grass, 149.
Orange, Osage, 62.
Orchidaceae, 46.
Orchis Family, 46.
Ornithogalum, 37.
Orobanchaceae, 208.
Osage Orange, 62.
Osmorrhiza, 160.
Ostrya, 52.
Oxalidaceae, 131.
Oxalis, 131.

Paeonia, 78.
Paeony, 78.
Paint-brush, 205.
Painted Cup, 205.
Pansy, 151.
Papaver, 91.
Papaveraceae, 89, 90.
Paper Mulberry, 62.
Pappoose Root, 85.
Parsley Family, 158.
Parsnip, 161.
Partridge Berry, 214.
Pasque Flower, 80.
Passiflora, 151, 152.

Passifloraceae, 151.
Passion-flower, 151, 152.
Passion-flower Family, 151.
Pastinaca, 161.
Pawpaw, 88.
Pawpaw Family, 88.
Pea, 129.

Pea Family, 117-119.
Peach, 116.
Pear, 108.
Pecan, 50.
Pedicularis, 206.
Pelargonium, 130, 131.
Pennywort, 178.
Pentstemon, 203, 204.
Peony, 78.

Pepper-and-salt, 160.
Peppergrass, 94.
Pepper Root, 97.
Periwinkle, 179.
Persimmon, 174.
Petunia, 201.
Phacelia, 188.
Philadelphus, 103.
Phlox, 185, 186.
Phlox Family, 185.
Phoradendron, 63, 64.
Phyllocactus, 155.
Physocarpus, 107.
Phytolacca, 69.
Phytolaccaceae, 69.
Picea, 16.

Pickerel Weed, 28, 29.
Pickerel-weed Family, 28.
Pignut, 51.
Pimpernel, 174.
Pine, 14, 15, 16.
Pine Family, 13.
Pine-sap, 166.
Pine-weed, 149.
Pink, 74, 75, 167.

INDEX

253

Pink Family, 71, 72.

Pinus, 14.

Pipe Vine, 65.

Pipsissewa, 165.

Pisum, 129.

Pitcher-plant Family, 101.

Plantaginacese, 211.

Plantago, 211, 212.

Plantain, 211, 212.

Plantain Family, 211.

Plantain, Water, 21.

Platanacese, 105.

Platanus, 105.

Plum, 116.

Podophyllum, 85. •

Poet's Narcissus, 43.

Poison Ivy, 138.

Poison Vine, 138.

Pokeberry, 69.

Pokeberry Family, 69.

Poke, Indian, 32.

Poke weed, 69.

Pokeweed Family, 69.

Polanisia, 99.

Polemoniacese, 185.

Polemonium, 186, 187.

Polygala, 134, 135.

Polygalacese, 134.

Polygala Family, 134.

Polygonacese, 66.

Polygonatum, 39, 40.

Polygonum, 67. •

Pomme Blanche, 126.

Pontederia, 28.

Pontederiacese, 28.

Poor Man's Weather-glass, 174.

Poplar, 47.

Poplar, White, 87.

Poppy, 91.

Poppy Family, 89, 90.

Populus, 47, 48.

Portulaca, 71.
Portulacacese, 70.
Portulaca Family, 70.
Potato, 200.
Potentilla, 114.
Prairie Apple, 128.
Prairie Fire, 205.
Prickly Ash, 133.
Prickly Pear, 154.
Primrose, 172.
Primrose Family, 171.
Primula, 172.
Primulacese, 171.
Prince's Pine, 165.
Privet, 177.
Primus, 116, 117.
Psoralea, 126.
Ptelea, 134.
Puccoon, 191.
Pudding-berry, 163.
Pulse Family, 117-119.
Purslane, 71.
Purslane Family, 70.
Pyrola, 165.
Pyrolacese, 164.
Pyrola Family, 164.
Pyrrhopappus, 236.
Pyrus, 108, 109.

Quaker Ladies, 213.
Quaking Asp, 47.
Quamoclit, 184.
Quercus, 56-59.
Quince, 108.

Radish, Wild, 96.
Ragweed, 232.
Ranunculaceae, 77, 78.
Ranunculus, 82, 83.
Raphanus, 96.
Raspberry, 111, 112.

254

FOUNDATIONS OF BOTANY

Rattan-vine, 144.

Rattlebox, 74.

Rattlesnake Master, 159.

Rattlesnake Weed, 235.

Redbud, 120.

Red Cedar, 19.

Red Root, 145.

Reseda, 100.

Resedaceae, 100.

Rhamnaceae, 143.

Rhamnus, 144.

Rhododendron, 167.

Rhus, 137, 138.

Ribes, 104.

Ribgrass, 212.

Robinia, 127.

Robin-runaway, 195.

Robin's Plantain, 229.

Rocky Mountain Bee Plant, 100.

Rosa, 115, 116.

Rosacese, 105-107.

Rose, 115.

Rose Family, 105-107.

Rosemary, 168.

Rowan Tree, 109.

Rubiaceae, 212, 213.

Rubus, 111-113.

Rudbeckia, 230.

Rue Anemone, 82.

Rue Family, 133.

Ruellia, 210.

Rumex, 66, 67.

Rush Family, 29.

Rutaceae, 133.

Rutland Beauty, 183.

Sage, 198.
Sagittaria, 21, 22.
Salicacese, 47.
Salix, 48.
Salsify,

Salvia, 197, 198.
Sambucus, 215, 216.
Sandalwood Family, 64.
Sand Bur, 200.
Sanguinaria, 90.
Sanicle, 159.
Sanicula, 159.
Santalacese, 64.
Sarracenia, 101.
Sarraceniaceae, 101.
Sarsaparilla, 157, 158.
Sassafras, 89.
Savin, 19.
Saxifraga, 102.
Saxifragaceae, 101.
Saxifrage, 102.
Saxifrage Family, 101.
Schrankia, 120.
Scilla, 36.
Scleranthus, 73.
Scrophulariaceae, 201, 202.
Scutellaria, 194, 195.
Sedge Family, 23.
Self-heal, 196.
Senecio, 232.
Sensitive Brier, 120.
Sensitive Rose, 120.
Service Berry, 110.
Shad Bush, 110.
Shame Vine, 120.
Sheep-lice, 189.
Sheep Sorrel, 66.
Shellbark, 51.
Shepherd's Purse, 98.
Sheriff Pink, 231.
Shin-leaf, 165.
Shooting Star, 172.
Shrub, 88.
Sickle Pod, 98.
Sicyos, 222.
Side-saddle Flower, 101.

INDEX

255

Silene, 73, 74.
Sisymbrium, 95.
Sisyrinchium, 46.
Skullcap, 194, 195.
Skunk Cabbage, 25.
Smilacese, 31.
Smilacina, 38.
Srnilax, 41, 42.
Suakeroot, 135.
Snakeroot, Black, 159.
Snakeroot, Samson's, 126.
Snapdragon, 203.
Snappers, 74.
Snapweed, 143.
Sneezeweed, 230.
Snowball, 216.
Snowberry, 217.
Solanacese, 198.
Solanum, 199, 200.
Solomon's Seal, 39, 40.
Sonchus, 237.
Sorrel, Sheep, 66.
Spanish Dagger, 38.
Spatter-dock, 77.
Spearwort, 83.
Specularia, 223, 224.
Speedwell, 205.
Spice Bush, 88, 89.
Spiderwort, 27.
Spiderwort Family, 26.
Spikenard, False, 38.
Spinach, 68.
Spinacia, 68.
Spiranthes, 46.
Spirea, 107, 108.
Spring Beauty, 70, 81.
Spruce, 16, 17.
Spurge, 136, 137.
Spurge Family, 135.
Spurge Nettle, 137.
Squash, 222.

Squawroot, 41, 208.
Squaw Vine, 214.
Squill, 36.
Squirrel Corn, 92.
Stachys, 197.
Staff-tree Family, 139.
Stagger-bush, 168.
Staphylea, 140.
Staphyleacese, 140.
Star-flower, 173.
Star-grass, 43.
Star of Bethlehem, 37.
Steironema, 173.
Stellaria, 72.
Stick-tights, 189.
Stitchwort, 72.
St. Johnswort, 149.
St. Johnswort Family, 148.
Stock, 99.
Strawberry, 113.
Strawberry Bush, 88, 140.
Straw Lilies, 33.
Streptopus, 39.
Sugar Pear, 110.
Sugar Plum, 110.
Sumach, 137, 138.
Sumach Family, 137.
Sun drops, 156.
Supple Jack, 144.
Sweet Alyssum, 99.
Sweet Bay, 86.
Sweetbrier, 116.
Sweet Cicely, 160.
Sweet Clover, 124.
Sweet Fern, 49.
Sweet Flag, 25.
Sweet Potato, 184.
Sweet-scented Shrub, 88.
Sweet William, 75.
Sycamore, 105.
Sycamore Family, 105.

256

FOUNDATIONS OF BOTANY

Symphoricarpus, 217.
Symplocarpus, 25.
Syringa, 103, 176.

Tamarack, 18.
Tangleberry, 170.
Tansy Mustard, 95.
Taraxacum, 235, 236.
Tassel Tree, 148.
Taxodium, 18.
Tecoma, 207.
Thalictrum, 84.
Thaspium, 161.
Thistle, 233, 237.
Thorn, 110.
Thuya, 18, 19.
Thyme, 198.
Thymus, 198.
Tiarella, 102.
Tickseed, 229, 230.
Tilia, 147.
Tiliacese, 146, 147.
Tinker-weed, 218.
Tipsin, 126.
Toad-flax, 64.
Toad-flax, Wild, 203.
Tomato, 200.
Tongue-grass, 94.
Toothache-tree, 133.
Toothwort, 97.
Tradescantia, 27.
Trailing Arbutus, 169.
Trefoil, Marsh, 178.
Trientalis, 172, 173.
Trifolium, 125.
Trillium, 40, 41.
Triosteum, 218.
Tropaeolacese, 132.
Tropseolum, 132.
Tropseoluin Family, 132.
Trumpet Creeper, 207.

Trumpet Flower, 207.
Tsuga, 17.

Tubuliflorae, 227, 228.
Tulip, 36.
Tulipa, 36.
Tulip Tree, 87.
Tupelo, 164.
Turkey Pea, 160.
Twin-flower, 218.
Two-eye Berry, 214.
Typha, 20.
Typhacese, 20.

Ulmaceae, 59.
Ulinus, 59, 60.
Umbelliferse, 158.
Umbrella Tree, 86.
Unicorn-root, 32.
Urtica, 63.
Urticaceae, 62, 63.
Utricularia, 209, 210.
Uvularia, 33.

Vaccinium, 170, 171.
Valerian, 220.
Valeriana, 220.
Valerianacese, 220.
Valerianella, 221.
Valerian Family, 220.
Veratrum, 32.
Verbascum, 202.
Verbena, 192, 193.
Verbenacese, 192.
Verbena Family, 192.
Veronica, 204, 205.
Vervain, 192.
Vetch, 128, 129.
Viburnum, 216, 217.
Vicia, 128.
Vinca, 179.
Vine Family, 145.

INDEX

257

Viola, 149, 150, 151.
Violaceee, 149.
Violet, 150, 151.
Violet Family, 149.
Virginia Creeper, 146.
Virginia Dayflower, 27.
Vitacese,' 145.
Vitis, 145, 146.

Wafer Ash, 134.
Wahoo, 140.
Wait-a-bit, 42.
Wake-robin, 40, 41.
Waldsteinia, 113.
Walnut, 50.

Walnut Family, 49, 50.
Wandering Jew, 28.
Water Chinquapin, 76.
Watercress, 96.
Waterleaf Family, 187.
Water-lily, 76.
Water-lily Family, 75.
Water Plantain, 21.
Water-plantain Family, 21.
Water Willow, 211.
Waxberry, 49.
Wax Plant, 183.
Wax-work, 139.
Weigela, 220.
White Hellebore, 32.
White Poplar, 87.
White Water-lily, 76.
Whiteweed, 231.
Whitewood, 87, 147.
Whitlavia, 188.
Wickakee, 205.

Wild Coffee, 218.

Wild Flax, 203.

Wild Ginger, 65.

Wild Hyacinth, 37, 92.

Wild Licorice, 215.

Wild Lily-of-the-valley, 39.

Wild Oats, 33.

Wild Pear, 110.

Wild Pink, 74.

Wild Potato Vine, 185.

Wild Raddish, 96.

Wild Sweet William, 186.

Willow, 48.

Willow Family, 47.

Wind-flower, 81.

Winterberry, 139.

Wintergreen, 165, 173.

Wistaria, 127.

Witch-hobble, 216.

Withe-rod, 217.

Woodbine, 146.

Wood-sorrel, 131.

Wood-sorrel Family, 131.

Yarrow, 231.
Yellow Flag, 46.
Yellow Pond Lily, 77.
Yellow Sweet Clover, 124.
Yellowwood, 121.
Yucca, 37, 38.

Xanthoxyluin, 133.

Zebrina, 28.
Zephyranthes, 42, 43.
Zizia, 161.

BIOUOGY LIBRARY

SEP 14 1932

MAR 2 1935

J ft 1935

MAR 1 5 1941
MAR 2 9 1949

LD 21-

U.C. BERKELEY LIBRARIES

BIOLOGY
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UNIVERSITY OF CALIFORNIA LIBRARY

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