THE LIBRARY
OF
THE UNIVERSITY
OF CALIFORNIA
LOS ANGELES
THE LIVING PLANT FROM SEED TO FRUIT
BLOOD-LIPPED ONCID (Oncidiuu,
The One-ids are a large group of Orchids, natives of tropical America and the West Indies. They all grow upon trees
(epiphytes) and exhibit great variety ot form and colour. The species figured is a native of New Grenada. The leaves
are thick and leathery, and the flowers home on erect spikes
POPULAR BOTANY
THE LIVING PLANT FROM SEED TO FRUIT
BY
A. E. KNIGHT
AND
EDWARD STEP, F.LS
VOLUME II
WITH
721 BEAUTIFUL ILLUSTRATIONS
AND
18 COLORED PLATES
NEW YORK
HENRY HOLT AND COMPANY
PRINTED IN GREAT BRITAIN
VOL. II.
CONTENTS.
QK
50
v.o.
CHAPTER
X. THE LEAF IN KELATION TO ITS ENVIRONMENT (continued) .
PAGE
289
XI. FLORAL FORMS AND THEIR EELATIONS TO INSECTS 312
XII. THE WELCOME OF THE FLOWERS 358
XIII. SOME PLANT MARRIAGES AND THE GUESTS THAT ASSIST AT THE FUNCTION . 422
XIV. THE PROMISE OF THE PLANT THAT is TO BE . . . . . . . 464
XV. HIDDEN MARRIAGES ............ 500
GLOSSARY OF TERMS 574
INDEX ... ........ 577
COLOURED PLATES.
Blood-lipped Oncid (Oncidium hcematochilum) Frontispiece
Facing page
Peach (Prunus pcrsica) ............ 289
321
353
385
417
449
481
, 513
Garlic (Allium acuminatum)
Close-headed Befaria (Befaria coarctata)
Variegated Oncid (Oncidium variegatum)
Blue Vanda (Vanda ccerulea) .
Cervantes' Odontoglot (Odontoglossum cervantesii)
Speckled Odontoglot (Odontoglossum ncevium)
Toothed Ceanothus (Ceanothus dentatus)
ILLUSTRATIONS IN THE TEXT.
PAGE
Alder . . . .514
p
Barberry ....
AGE
405
Alocasia spectabilis .
443
Bedeguar Gall, Flowering
Antheridium, An
505
Branch of a Rose sur-
Antherozoids
506
rounded by a
304
Anthers and their Dehiscence
354
Beech, Hairy Galls on.
305
Apple . . . 357,
473
Begonia, Abnormal Flower of
324
Aralia nudicaulis, Flower-
— Section of
332
buds of ...
386
Bellflower, Nettle-leaved
425
Arbor-vita?, Cone of Chinese
489
Birth wort .
374
Archegonium, An
505
Bleeding Heart .
320
Arum, Giant
317
Brefeldia maxima
570
Asclepias cornuti, Pollinia of
408
Burweed .
486
Ash
368
Buttercup .
321
Aspen ....
448
— Apocarpous fruits .
334
Aspidistra . - .
376
442
— from below .
— Rosaceous Corolla of
321
312
PAGE
Buttercups, Section showing
receptacle to which the
carpels are attached . 322
Cabbage, Skunk . . 387
Cactus, A Prickly Pear . 300
Calla, ilarsh . .361, 441
Campion, White. . 340, 446
Candytuft, Evergreen . 486
Carrot . . . .332
Catasetum tridentatum 408, 409
Caterpillar-plant . . 481
Chestnut, Horse . . 479
— Section of (JIale Flower). 366
- Sweet . . 367, 462
Chrysanthemum, Annual . 352
Clavaria, Crested . . 538
I PAGE
Clematis caorulea, Flower of 328-
— Garden . . .335-
Climbing Cobasa, Section of
flower in first stage of
development ; and fruit 373^
Sectionof flower in third
stage of development . 373!
Clubs, Fairy
. 549
Cluster-cups
546
— Hawthorn
550
Coco-nut, Double
488
Columbine .
348
Comfrey .
407
Convolvulus, Seaside
345
Corallina officinalis
553
Corncockle
474, 496
2054333
Illustrations in the Text, Vol. II.
PAGE
mar PAGF
PAGE
Cotton-grass . . .453
Horn of Plenty . . .548 Oak, Bristle-gUls on . . 302
Sallow . . . .369
Cowslip . . . .315
Horse Chestnut . . 360, 479 — Cherry-galls on . . 301
Samphire . . . .493
Cranesbill, Meadow . . 374
Horsetail . . . . 512 — Spangle-galls on . . 301
Saxifrage . . . ,394
— Blood-Red . . .494
— Field . * . 514, 515 — Turkey . . . .495
— Mossy . . . .383
Great . . . 519 i Oar-weed . . . .291
Seaweed, A Red . . 553
Crocus . . . .334
Hydrangea . . .351 Oat 316
— Ash -leaved . . .559
— Indian . . . .380
Inflorescences, Definite . 327 Odontoglossum alexandwe , 412
— Forked . 563
Lip of flower showing
— Indefinite . . . 331 i Oncid, Tiger-striped . . 384
Sensitive Plant . . . ->92
fringes and streaks of
Iris 477 Orange, Myrtle-leaved . 490
Snapdragon, A portion of the
colour— honey-guides . 382
Jania rubens . . . 557 j Orchis, Bird's-nest . . 437
stigma and style . 326
Hairs of a portion of
Jericho, Rose of . . 485 ' — Butterfly . . .426
— Section through pistil o* 322
two of the fringes of the
Job's Tears . . . 492 . — Dwarf . . . .432
Snowdrop . . . 359
tip highly magnified . 382
Kalmia latifolia, Flower of . 406
— Goodyer's . . .431
Sorrel, Common . . 458
Cuckoo-flower . . .393
Lady's Tresses . . .419
— Green-man . . . 433
Sparassis, The . . . 539
Cuckoo-pint . . .313
Lapageria, Section of. . 444
— Green-winged . . 436
Spear Plume-thistle . . 299
Cucumber, Squirting . . 469
Larkspur . . 390, 481, 496
— Fragrant . . .435
Spleenwort, Maidenhair . 500
Cyclamen . . . .360
— Garden . . . .339
— Musk . . . .440
Stamens of (a) Litsaea ; (6)
Cyperus, False . . .459
Leocarpus fragilis . .573
— Purple .... 434
Pyrola; (c) Garcinia . 356
Dandelion . . 467, 492
Leptodermis lanceolata . 498
— Pyramidal . . .438
Star, Earth . . . 537
— Floret of . . .329
Lichen, A . . . .527
— Spotted . 427, 429, 430
Stinging Hair of Stinging
Dead-nettle, White . . 346
— Sections through . . 528
Ovaries, Uniovular . . 465
Nettle . . .296
Dewberry . . . .471
Lily, African . . .395
Oxlip . . . .376
Stinging Nettle . . .303
Dog Lichen . . .533
Liverwort . . 522, 526
Pseony, Follicles of . . 481
Stock . . . .482
Dragon's-mouth, Mountain . 391
Loosestrife, Creeping . .312
Pansy Flower, Section of . 392
Stonewort . . . .552
Dry Rot .... 542
— Purple . . . 363, 377
Papilionaceous corolla . 348
Stork's-bill, Hemlock . 423, 424
Earth-Nut . . .484
— — Illustrating the tri-
Pasque-flower, Section of . 396
Strawberry . . . 472
Ergot . . . .541
morphism of the
Passion-flower, Blue . . 422
Sycamore .... 496
Fern, Cup -shaped Indusinm
flowers . . .378
Pea, Campylotropous Ovule
Tangle, Sugar . . . 554
of Filmy . . .506
Lousewort, Marsh . . 365
of . . .466
Teasel . . . .297
— Hard .... 501
Lucerne . 482
— Common . . . 330
Telegraph -plant . . . 293
— Male . . 502, 503
Lupin .... 482
— Flower of ... 402
Thorn-apple . . . 476
^- Prickly Buckler . . 507
— Leaves of ... 289
Pea Flower, Section of . 402
Toadflax, Ivy-leaved . . 483
— Sea . . . 511
Magnolia . . . .379
— Gall, Spiked . . 308
— Yellow . . . .349
— Spores Germinating . 504
Mallow, Common . . 494
Peacock's-tail . . .560
Toadstool, The Solitary . 536
Fig . . . . .388
Marigold, Marsh. . . 362
Petty Spurge, Inflorescence Of 396
Touch-me-not Balsam Ex-
Figwort . . . .350
Meadow-saffron . . .477
Pillwort . 509, 510, 512, 513
pelling its Seeds . . 470
Flamingo Plant . . .399
Meadowsweet, American . 32?,
Pimpernel . . . .478
Tremella mesenterica . . 544
Flowers, ^Estivation of . 329
Medlar . . . 473, 475
Pine, Austrian . . 451, 499
Trichia varia . . .569
Forget-me-not . . . 385
Megarrhiza calif ornica, Spiny
— Scots . . 449, 450
Trigonia villosa . . .498
Foxglove . . 343
Fruit of 466
Piiifc SIR
Fuchsia .... 310
Milk-thistle . . . 489, — Mossy . . - .344
Urchin Crowfoot . . 490
Fungus, Bird's-nest _ . 546
Mitrula phalloides . . . 545 Pistils . . . .355
Valerian, Great . . 341
— Candle-snuff . . . 547
Monkshood . . .336 Plantain, Large . - .457
Vallisneria spiralis . .413
— Jew's-ear . . .540
Moonwort .... 508 — Lamb's-ear . . . 381
— Flowers of . . . 414
Ginger, Wild . . .403
Morel .... 543 Plants, Lime-secreting . 556
Violet, Sweet , . . 358
Goatsbeard . . 319, 364
Morning Glory . . . 373 i Plumbago . . . .360
Water-dock, Great . . 455
Gourd . . . .489
Moss, A Scale . . .524 Plume, The Crimson . . 557
Water-lily, White . . 464
Grape Vine . . 344, 463
Great Panicled Sedge,
— Beard . . . . 529 Plum, Section through a . 488
Wheat .... 492
Pollen-grains of . .454
Gum-Arabic Tree . 485
— Hair . . . 520,523 American Plum-tree . 487
Willow-herb, Great . . 372
Gymnosporangium clavariio-
— Lesser Alpine Club . 517 , Pollen-grain Magnified . 454
Winter Cherry . . .341
forme . . . .551
Hairs from the Leaves of
— Marsh Club . . . 516 j — of Evening Primrose . 400
— Screw . . . . 521 1 — Passion Flower . . 400
Wistaria, Abnormal Flower of 324
" Witches Broom " on Scots
Various Plants (ilagni-
Mosses, Two . . . 525 — Pumpkin . . . 400
Pine . . . .309
fied) . . . . 295
Mould, Brown . . . 534 — Scot's Pine . . . 400
Wood Anemone , .417
Hard Heads . . . 371
Mucilago spongiosa . . 568
Polysiphonia . . .558
— Rush, Field . . . 418
Hazel . . . 456, 491
Mulberry .... 473
Poplar . 496
— Sage .... 460
— Flowers . . . 416
Mullein, Black . . .291 Potato-blight . . .532
— Sorrel . . . . 290
Heath, Hispid . . .350
Heather or Ling . . 447
Myosotis Flowers. . . 370 Primrose. Bird's-eye . . 389
Myxomycete, Development j Primula obconiea . . 307
— — Expelling its Seeds . 468
• Seed of , . 469
Helleborine, Broad-leaved . 421
of a . . . . 571 Prothallium, A . . . 504
— Spurge .... 397
Henbane . . . 338, 353
Nail-galls . . . . 306 Pternan'ira cordata . . 338
Wrack, Bladder 562, 564, 565
Henbit .... 370
Herb-paris. . . .314
Holly . . . .398
— Hedgehog Variety of . 296
Halymenia ligulata . . 561
Honesty . . . 340,485
Hop Hornbeam . . . 497
Nasturtium . . 337. 494 Puft-balls, A Cluster of . 535
— with spurred calyx . 337 j Purse, Shepherd's . . 37o
Nectar Glands . . .393 Quillwort . . . .513
Nectaries . . . .390 Ramalina scopulorum . . 531
Needle Whin . . .428 Rampion . . . ,347
Nettle, Flower of . . 414 ! Rose, Dog- and Field- .' 333
Nut, Brazil . . .480 Sage, Flower of . .404
— Saw-Edged . . .555
Wych Elm . . . 493
Yarrow . . . .445
Yew . . . 497, 498
Yoke-thread . , .566
Yucca, Flower of . . 410
Moth . 410
Horehound, Black . .493
Hornbeam . . . 46i
Oak • • • . . 452 St. John's Wort, Largc-
— Apple . . . .3111 flowered . . .325
Gathering Pollen . 410
— Plant . . . 411, 439
The Peach is belies
The
PEACH fpr
n Eii rope from very ancient days,
"amily as the Plums and Sloe.
CHAPTER X
THE LEAF IX RELATION TO ITS ENVIRONMENT— (Continued}
THOSE who have never studied under the microscope the singular forms
of the covering hairs of leaves, have pleasures offered to them for
many a winter evening. Possibly a glance at the illustrations which ac-
company this part of our text will help to kindle interest in the subject.
Pig. 3606 represents some simple hairs of a species of Brassica : i some
fwked hairs of the Whitlow Grass (Draba verna) ; and h a stellate hair of
the pretty Alpine Madwort (Alyssum spinosum). In these three specimens
the hairs are unicellular, but multicellular hairs are met with in a large
number of plants. When
the cells grow together in a
line, like the beads of a
necklace, the hairs are said
to be moniliform. Of this
kind are the epidermal hairs
of the Marvel of Peru (Mira-
bilisjalapa, fig. 360j) and of
the Virginian Spiderwort
{Tradescantia virr/inica, k).
When the cells spring from
a common point, as in the
Cretan Horehound (Marru-
bium creticum, «), the hairs FlG- 352.— LEAVES OF LUPIN.
are said to be tufted. The flrst shows thtejy°10
Branched hairs, which need
no describing, are found in several plants. They give the downy (tomen-
tose) appearance to the leaves of Nicandra anomala, a Peruvian plant of
medicinal value (/), and to the decurrent leaves of the Great Mullein (IV-
bascum thapsus). In a few plants of succulent habit, like the South African
Eocheas, excessive evaporation is prevented by the development of special
flinty cells on the epidermis of the thick fleshy leaves (g). They are many
times larger than the ordinary epidermal cells, and their walls are largely
composed of silica. A covering of this kind is simply the salvation of its
possessor in time of drought. Not that fleshy leaves are ill-adapted to
II— 1 289
of the leaflets clurinsr the day ; at night
iown close to the stalk.
290
HUTCHINSON'S POPULAR BOTANY
FIG. 353. — WOOD-SORREL (Oxalis).
During the day the leaflets spread out from the leaf-stalk ;
FIG. 354. — WOOD-SORREL.
—at night, and dining rain, they fold down close to the
leaf-stalk.
dry climates ; the reverse is the
case, the transpiring surface of such
leaves being much smaller than if
the}' were flattened out into thin
and spreading forms. Yet even
the smaller surface needs to be
protected, and this it is which
gives its value to the flinty armour.
The vertical position which
many leaves assume is likewise a
means of checking excessive trans-
piration. One has met with the
expression, '• the shad&wless forests
of Australia," and the phrase is not
inappropriate, for the leaves of
many Eucalyptus-trees and Acacias
(the chief timber trees in Aus-
tralian woods) do not assume a
horizontal position like the leaves
of most European forest-trees, but
are placed vertically on edge ; and
thus the shadows which they cast
at midday are reduced to a mere
line. This, as we need scarcely
add, is due to the fact that the
rays of light fall upon the up-
turned edges of the leaves and not
upon the broad surfaces of the
blades.* The latter, indeed, escape
altogether the meridian sun, though
they get the full benefit of his less
scorching rays at the beginning
and close of the day.
The interesting Compass-plant
(Silphium laciniatum) should not
be forgotten when speaking of the
position assumed by leaves in refer-
ence to transpiration. Longfellow's
Evangdine contains a graceful de-
scription of the plant (though he
confuses flower and leaf), which
* This is also a protection from the in-
jurious effect on the chlorophyll corpuscles
of the intense sunlight.
FIG. 355. — BLACK MULLEIN (Verbascum nigrum).
The leaves are downy with a dense growth of stellate hairs. The yellow flowers are closely packed in long
racemes which are a foot and a half long. EUHOPR, SIBERIA.
291
292
HUTCHINSON'S POPULAR BOTANY
FIG. 356. — SENSITIVE PLANT (Mimosa pudica).
Day position of leaf and leaflets.
specimens of this plant not only assume an
almost vertical position, but by a singular
twisting of their blades, bring themselves
into a position which has earned it the name
of Compass-plant. The lobes of each pinnate-
parted leaf, extending like fingers on either
side of the midrib, are said to point due north
and south ; but some observers who have
watched the plant in its native habitat have
thrown considerable doubt upon the state-
ment, as they have found the leaves point-
ing in all directions.
The leaves of the Marram (Psamma aren-
aria) exhibit a special structure in view of
this same purpose — the prevention of ex-
cessive loss of water. The plant in ques-
tion is the Common Matweed of our sand-
hills, whose spreading fibrous roots are so
useful in binding together the shifting
sands on the coasts of Norfolk and Holland,
and in many other places. It has been noted
that " on wet days the leaves open longi-
tudinally, so that their inner surface is freely
exposed to the air, and the stomata which
are situated there may not have their func-
is widely distributed
over the North Ameri-
can prairies :
Look at this delicate plant
that lifts its head from
the meadow,
See how its leaves all point
to the north, as true as
the magnet ;
It is the Compass-flower,
that the finger of God
has suspended
Here on its fragile stalk, to
direct the traveller's
journey
Over the sea-like, pathless,
limitless waste of the
desert.
The leaves of young
FIG. 357. — SENSITIVE PLANT.
At night, or when touched, the leaf hangs
down, and the leatlcts fold closely together.
THE LEAF IN RELATION TO ITS ENVIRONMENT 293
tions restricted : in dry
weather, on the con-
trary, the leaves are
rolled up so that the
leaf almost forms a tube,
the outer surface of
which is hard and quite
impervious to water."
The mechanism by which
this is effected is to be
found in certain cells,
which form longitudinal
rows at the base of the
furrows on the under
surface of the leaves,
and which are very sensi-
tive to moisture. In
damp weather the cells
increase in turgid ity by
absorption of water, and
the leaf opens.
In concluding these
observations on the
dangers to plants from
excessive heat, and the
means provided by
Nature to counteract
those dangers, one is
naturally led to the op-
posite side of the sub-
ject, and the question
arises, If too much heat
be injurious to a plant,
may not, under contrary circumstances, too great loss of heat be injurious
too ? Moreover, if the all-wise Mother has devised means for protecting
growing plants from the one evil, may she not also have devised means
for protecting them from the other?
To both questions an affirmative answer may be given. Loss of heat
has no less to be provided against than excessive transpiration — the damp
and chilly nights must be taken into account quite as carefully as the dry
and sunny days ; for growth goes on in the plant more rapidly in some cases
by night than by day, and if it were systematically deprived of heat during
the hours of darkness, it would soon languish and die. Now the means
which Nature has devised for protecting growing plants from loss of heat
FIG. 358. — TELEGRAPH-PLANT (Desmodium gyrans).
The small lateral leaflets move un and down, twisting at the same time, and
describe a kini of ellipse. The movement i.s not continuous, and is much
influenced by temperature.
294
HUTCHINSON'S POPULAR BOTANY
are beautifully simple.
What is known as the "sleep" of plants — in other
words, the nocturnal drooping and
folding of leaves and flowers — com-
prehends the chief of those means,
and we shall here confine our re-
marks to this well-known phenome-
non.
If you have ever sauntered
through a garden by night, and
examined, lantern in hand, the
dew-drenched vegetation, you will
have stumbled upon some curious
discoveries. It is easy to imagine
the surprise evoked during such
an excursion. As you pause before
one of the well-ordered beds, and
look down at the familiar plants,
you involuntarily ask yourself,
What has become of the flowers ?
A few, indeed, are still plainly visi-
ble : but there are others that you
miss, nor do you realise what has
become of them until, on closer ex-
amination, you discover that some
are closed, and others are hanging
down their heads so that only their
green collars (the calyces) meet the
eye : while others, again, have skil-
fully concealed themselves behind
their own foliage leaves.
The leaves, too, appear to be
wonderfully changed. " We are
all a-noddin', nid-nid-noddin',"
seems to be their drowsy language.
The Trapceolums no longer confront
the vault of heaven with their green
shields, which hang listless at their
sides ; the Lupins have folded up
their digitate leaves like umbrellas
(fig. 352) ; and on every hand the
foliage seems heavy with slumber.
It may be cruel to unsettle so
pleasing a fancy, but the phenomenon described, and which is popularly
known as the sleep of plants, is simply a part of Nature's plan for guarding
Ph/)to W [E. Slep.
FIG. 359 — OAB-WEED (Laminaria digitata),
One of the largest of our native seaweeds. The specimens
photographed were fifteen feet long.
FIG. 360. — HAIRS FROM THE LEAVES OF VARIOUS PLANTS (MAGNIFIED).
(a) Glandular hairs of Snapdragon ; (6) simple unicellular hairs of a Brassica ; (c) glandular tentacle of ^"n|jp^' >
(rf) sessile L-land of Hop ; (?) tufted hairs of Cretan Horehound ; (0 branched hairs of Nicaiulni ; (;/) ..M-/.\
coverm.,' of'Rochea : (h) stellate hair of Alpine Mr.dwort. ; (O forked hairs of Whitlow Grass ; (/) munform Hairs
of Marvel of Peru ; (fc) muriform hairs of Virginian Spiderwort.
^- 295
296
HUTCHINSON'S POPULAR BOTANY
FIG. 361. — STINGING
HAIR OF STINGING
NETTLE.
her vegetable proteges against excessive loss of heat.
The " sleep " position of leaves is, in fact, a protective
arrangement. By folding themselves together and as-
suming, as far as possible, a vertical position, radiation
is materially checked, and thus the plants undergo no
serious fall of temperature daring the night. We must
not be misled s by this popular term "sleep" into sap-
posing that the nutritive processes of the plant are
suspended at this time. " The drooping position as-
sumed by the leaflets of Oxalis is simply protective ; there
is no correlation between the assumption of the drooping
position and the temporary loss of the power of assimila-
tion. Preparations made at night from the leaves of
Oxalis when in the drooping nyctitropic position show a
normally active power of assimilation, and the same is
the case with leaflets of Mimosa. The movements per-
formed in assuming the nocturnal nyctitropic position
of certain ' sleep ' plants are not accompanied by any
corresponding internal changes or alterations in the power of assimilation.
In this respect the sleep of plants is more external and apparent than
internal and real '' (A. J. Ewart, B.Sc., in Journ. Linn. Soc. [Botany],
vol. xxxi., 1896).
Plants of the great Leguminous order, to which the Acacias, Mimosas,.
Peas, and Trefoils belong, exhibit the phenomenon of which we are treating
in a very striking manner. The Wood-sorrels (Oxalis acetosella, corniculata,
and strida), also, are extremely sensitive to changes of temperature, folding
down their leaves even in the daytime if rain threatens (figs. 353, 354), while
a blow from a stick will cause them to shrink together with affecting
suddenness. Sensitiveness is carried to an extreme in a tropical species of
this genus, Oxalis sensitiva, concerning which it is affirmed that even the
disturbances of the air caused by the approach of man are sufficient to-
induce the phenomenon, the
petioles relaxing and the pinnate
leaflets falling together like the
leaves of a book. This is also
said to be the case with several
of the Mimosas ; but the two
species which are most common
in English stove-houses (M.
pudica, figs. 356, 357, and M.
sensitiva), though collapsing
readily at the slightest touch,
certainly do not exhibit such
FIG. 362.-HEDGEHOG VARIETY OF HOLLY. extreme sensibility in this
THE LEAF IN RELATION TO ITS ENVIRONMENT 297
country. Touch a leaf-point of Mimosa, and the small leaflets fold together,
and the stalk to which they are attached drops suddenly. The leaflets on
other branches of the compound leaf act in the same way ; and finally the
main leaf-stalk drops suddenly. The Mimosas have received poetic treatment
from more than one distinguished writer. Erasmus Darwin says :
Weak with nice sense the
chaste Mimosa stands,
From each rude touch with-
draws her timid hands ;
Oft as light clouds o'erpass
the summer glade,
Alarmed she trembles at the
moving shade ;
And feels, alive through all
her tender form,
The whispered murmurs of
the gathering storm ;
Shuts her sweet eyelids to
approaching night,
And hails with freshened
charms the rising light.
The movements of
so-called sensitive plants
are probably in part due
to a peculiar modifica-
tion of certain of their
leaf-cells, which — in the
Mimosas, at least — are
so constructed that
delicate threads of pro-
toplasm pass through
their walls and maintain
a connection with the
living matter of adjoin-
ing cells. Thus the
effects of a touch on one photo W t£- S:eP-
part Of a leaf may be FlG' 363.— TEASEL (Dipsacus sylvestris).
... -, ,-. . Showing the protective spines on the stem, and the spiny bracts inter-
transmitted all over it ; ppersed with the f,0wers in the flower-head.
and if, as is not un-
likely, these perforated cells are distributed through the stem and branches
as well as the leaves, the effects spoken of may be carried to every part
of the plant.
The drooping of the leaf-stalk (which, as in the leaf of Mimosa pudica,
may alter its angle with the stein from ninety to thirty degrees) is caused
by a beautiful piece of mechanism. At the base of the leaf-stalk there is
298
HUTCHINSON'S POPULAR BOTANY
a little cushion-like swelling, called the pulviniis (the Latin word for
"cushion"), which contains a woody centre surrounded by parenchymatous
cells, rich in water. When one of the pinnate leaflets is touched, the
effect is transmitted to the pulvinus by the threads of protoplasm, with
the result that the water passes from the cells on the lower to those on the
upper side, causing the former to pass from a distended into a flabby state.
They thus become temporarily unfit to support the leaf-stalk, which in
Photo by]
FIG. 364. — HOLLY (Ilex aquifolium).
Showing the spiny, dentate leaves and the clusters of red berri
[E. Step.
consequence falls of its own weight. By and by the water gains its original
distribution, and then the leaf-stalk resumes its horizontal position.
The celebrated Telegraph-plant (Desmodium gyrans) is even more
interesting than the Mimosas. It is an East Indian plant with violet flowers
and trifoliate leaves, and the latter are in motion night and day. In bright
sunshine the two lateral leaflets jerk up and down, and from side to side, in
a remarkable manner, while the large terminal leaflet goes through similar
though less perceptible movements (fig. 358). Should these movements be
artificially checked for a while, the leaf will start again with increased
city directly the retarding influence is removed. During darkness the
Photo by}
\Jlcnry Ir
FIG. 365. — SPEAK PLUME-THISTLE (Cnicus lanceolatus).
All parts of tl.e plant above ground are armed with needle-like spines. The florets are specially adapted for the
_^r visits of bees with long probosces, particularly humble-bees.
300
HUTCHINSON'S POPULAR BOTANY
terminal leaflet assumes the perpendicular position which has been already
shown to be characteristic of " sleeping " leaves.
The trembling movement of the leaves of the Aspen (Populus tremula)
has supplied many figurative allusions to prose-writers and poets, and the
phenomenon deserves a passing notice. The quivering is due to the
elasticity of the long flattened foot-stalks ; and Mr. Colbourn, of Hobart,
suggests that the rapid movement in the air enables the leaf to throw off
the excess of moisture which collects on it in the damp situations of the
tree. Some force is given to this view if we look at the Aspen or the Black
Poplar immediately after rain, when we shall find great numbers of the
leaves held together bv moisture. Kerner, however, regards the motion as
an arrangement for protecting the flat broad
leaves against crushing ; but many other broad
flat leaves are without this provision. He
further remarks that the elasticity is due to the
development of bast-strands in the leaf-stalks.
We have now considered a few of the dan-
gers to which the green leaves of plants are
exposed, but the subject would be very im-
perfectly treated were no mention made of a
danger of another kind. This form of danger
belongs to the animate rather than the inani-
mate world — to " wild beasts and beasts of the
field and creeping things'' rather than to heat
and cold and other such phenomena and forces.
Innumerable animals feed upon the green
tissues of plants, and find in a vegetarian diet
their only sustenance; indeed, if Nature had
not provided special contrivances to keep off
these devourers, it is next to certain that whole
families of plants would long since have van-
ished from the face of the earth. A few of
these contrivances have been incidentally re-
ferred to in former chapters. When speaking of the sap of plants, we
showed that the milky juice of the Common Lettuce (Lactuca sativa) pro-
tected the plant from the depredations of ants and other leaf-eating insects;
and on a later occasion we saw that the thorns or spines in such plants as
Blackthorn (/Yunua spinosa). Spiny Restharrow (Ononis spinosa),
bpurges (Euphorbia), etc., render acceptable service by keeping off brows-
ing cattle and herbivorous wild animals. But the subject was only lio-htlv
ouched, and-from the nature of the connection in which it was intro-
uced-many of these protective contrivances were not alluded to at all.
^or example no mention was made of pricttes. Prickles are another
thorn. They are not, like spines, branches which have degenerated,
FIG. 366.— A PRICKLY PEAR
CACTUS (Opuntia multiflora),
Protected by fine barbed bristles.
THE LEAF IN RELATION TO ITS ENVIRONMENT
301
I
P/fo/o &«/]
FIG. 367. — SPANGLE-GALLS ON OAK.
for they spring
from the epider-
mis or cortex of
a plant member,
and contain no
fi br o -vascular
bundles ; while
spines, it will be
remembered, are
traversed by
those bundles
which connect
them with the
vascular system
of the stem arid
root. Good ex-
amples of prickles
are offered by the
Dog-rose (Rosa
canina) and the
Holly (Ilex), to name no other plants. In the former they occur on the
petioles and branches ; in the latter they spring from the margins of the
leaves.
Plants of a prickly nature seldom develop those structures on leaves and
branches which are out of reach of grazing animals. The Common Holly
(Ilex aquifolium),
the bristly den-
tate leaves of
which form a
characteri s t i c
feature of
shrubby speci-
mens of the
plant, produces
only unarmed
leaves, with en-
tire margins,
on its upper
branches, when it
attains to t h e
dignity and di-
mensions of a
tree. Indeed, the
gradations from FIG. 368. — CHERRY-GALL ON OAK.
Photo by}
[/. Ilolmns.
302
HUTCHINSON'S POPULAR BOTANY
m
the prickly to the unarmed forms of leaves in the plant named are so
numerous and marked, that the species has been separated into varieties
to distinguish them. Compare, for example, a leaf of Henderson's Holly
(Ilex a. hendersoni) with one of the Donington variety (Ilex a. donington-
ensis), and both with a leaf of the Hedgehog Holly (Ilex a. ferox, fig. 36*2) ;
which latter has prickles not only at the margin, but also on the upper
surface. Its popular name is, indeed, exceedingly appropriate ; so, too, is
its Latin appellative — ferox,
" savage." Several plants of
the large genus Solarium, to
which the Potato-plant and
Woody Nightshade belong
(e.g. S. fontanesianum, jac-
quini, and maroniense), have
spiny erections on both sides
of the leaf. They are borne
upon the midrib and veins,
and make the plants ex-
tremely awkward things to
handle.
Many other protestive
arrangements more or less
similar to those described
occur readily to the mind ;
as, for instance, the sharp,
strong, needle-shaped (acicu-
lar) leaves of many Grasses ;
the formidable thorny ter-
minations of the leaves of
the Agaves, and the spine-
bordered lobes of leaves like
the Thistle (Carduus), Teasel
(Dipsacus), and Acanthus. It
has been asserted that in
the- Southern Alps sheep will
frequently return from pasture with their nostrils cut and bleeding, and
the shepherds know at once that the cause of the mischief is a species
f stiff-leaved Grass, Festuca alpestris, which they seek to destroy by burn-
ing. In some instances, Grasses which cause discomfort to grazing animals
will be dealt with by the animals themselves, who seize them low down
with their teeth and tear them from the ground. Kerner saw thousands
tufts of the Mat-grass (Kardus stricta), which had been rooted up by
oxen lying dried and bleached by the sun on some meadows in the
Tyrolese Stubaithal.
FIG. 369. — BRISTLE-GALL ON OAK.
These galls are caused by the gall-wasp. Andricus lucidus.
Photo by]
FIG. 370. — STINGING NETTLE (Urtica dioica).
Theleaves and stem are covered with hollow stinging hairs through which a poison is introduced to the victim's flesh.
The small green flowers are wind-pollinated. NORTH TEMPERATE REGIONS, N. AFRICA, THE ANDES.
303
304
HUTCHINSON'S POPULAR BOTANY
More formidable than air^ of the protective weapons yet mentioned
are the barbed bristles which surround the buds on many of the Opuntias.
Each of these is a sort of compound fish-hook in miniature, and woe to
the unwarv animal who pushes his nose against the smallest bunch of
them! The little hooks enter the tender flesh, and cause intolerable itching.
which is often succeeded by painful and. it may be, dangerous inflammation.
The tormenting bristles are easily driven deeper, but the backward-pointing
barbs tear the flesh unmercifullv
when any attempt is made to
withdraw them. One species,
Opuntia ficus-indica, better known
as the Prickly Pear, is abundantly
naturalized in the Mediterranean
area, where it forms inpenetrable
fences. Another species. Opuntia
feroXj is said by Schleiden to be
especially remarkable because of
the strength and size of its defen-
sive thorns. " Among the hairs
and smaller spines," he says,
" arise very long and thick spines,
in different form and number,
which give the best characters
for the determination of the
species. In some, these are so
hard and strong that they even
lame the wild asses which in-
cautiously wound themselves when
kicking off the spines to reach
the means to still their thirst. In
Opuntia tuna, which is the kind
most frequently used for hedges,
FIG. 371. — FLOWERING BRANCH OF A ROSE SUR-
ROUNDED BY A BEDEGUAR GALL.
The gall-fly and grub of same are shown in the corner of
drawing.
they are so large that even the
buffaloes are killed by the inflam-
mation following from these spines
running into their breasts. It was this species, also, which was planted
in a triple row as a boundary line between the English and French in the
island of St. Christopher." Fig. 366 represents a flowering branch of
Opuntia multiflora.
No account of the protective armature of green leaves would be complete
without a reference to stinging hairs. The mention of these very remarkable
structures brings to mind the Common Nettle (Urtica dioica}— a weed that is
known to every child. Let us take a peep through the microscope at one
of its stinging hairs, and try to realise what takes place when any rash
THE LEAF IN EELATION TO ITS ENVIRONMENT
305
meddler with the plant gets stung. Our picture (fig. 361) represents a hair
in section. It consists of a long, tapering single cell, rising from a cushion-
like base, and widening at the apex into a little knob, which is bent some-
what out of the perpendicular. At the point where this bend takes place
the cell-wall is extremely thin — so thin that a very slight touch suffices to
break off the knob. When, therefore, such a touch is given, the mischief
is done, and the acrid
irritating fluid contained
in the cell escapes at the
point of rupture and
enters the tiny wound
which the vitreous apex
of the hair has made.
The fluid consists of
formic acid and a sort
of unorganized ferment
or enzyme, the latter
being thought to be the
more poisonous property
of the two. It may be
added that the break takes
place obliquely (a conse-
quence of the bend above
described), so that the
broken end resembles the
poison-fang of a serpent
— to which, indeed, it has
sometimes been com-
pared.
A brush from the leaf
of any of the British
Nettles ( Urtica dioica,
urens, and pilulifera) is
doubtless a light matter,
but to be stung by some
Photo by}
IE. Step.
FIG. 372. — HAIRY GALLS ON BEECH,
Caused by a two-winged fly (Hormomijia).
of the Asiatic species is
a very different thing. The great Shrubby Nettle (Urtica crenulata)
of Northern India, for instance, is a nettle to beware of. " This plant,"
says Sir Joseph Hooker in his Himalayan Journals, ': called ' mealum-ma,'
attains fifteen feet in height ; it has broad glossy leaves, and though
apparently without stings, is held in so great dread that I had difficulty in
getting help to cut it down. I gathered many specimens without allowing
any part to touch my skin ; still, the scentless effluvium was so powerful that
mucous matter poured from my eyes and nose all the rest of the afternoon in
ii— 2 '
306
HUTCHINSON'S POPULAR BOTANY
such abundance that I had to hold my head over a basin for an hour. The
sting is very virulent, producing inflammation ; and to punish a child with
'mealum-ma' is the severest Lepcha threat." The writer explains in a
footnote that the hairs are microscopically small, and they only sting
violently during the autumn. M. Leschenault, a French botanist who had
the misfortune to be stung by the " mealum-ma '' at this particular season,
while gathering one of the leaves for his herbarium, describes the symptoms
that followed as anything but pleasant. At first he felt only a slight
pricking which he wholly disregarded ; but the pain gradually increased,
and at the end of an hour it had become excruciating. The parts affected —
the first three fingers of his left hand— felfc
as though they were being rubbed with a
hot iron. Before long the pain had spread
up the arm to the arm-pit : and within five
hours of being stung the torture was increased
tenfold by an ominous contraction of the
muscles of the jaw, which made him fear an
attack of lockjaw. However, the latter symp-
toms passed away towards evening, and from,
that time the pain continued to decrease,
though upwards of nine days elapsed before it
^^H^^^^K^ entirely left him.
^W\ That the inferior animals are sensitive to
"•^^ the stings of plants no less than man, and
therefore that stinging hairs may be a real
protection from grazing animals, is illustrated
by the fact mentioned by Baillon, that the
natives of Java rub buffaloes with a species
of Nettle (Urtica stimulans) in order to excite
them to fight with tigers. On the other hand,
these vegetable fangs are innocuous to certain
leaf-eating insects, which feed upon them
with impunity ; indeed, it is well known that
the leaves of our British Nettles, which are all furnished with stinging
hairs, form the only food of the caterpillars of three of our most beautiful
butterflies— namely, Vanessa atalanta, V. io: and V. urticce. But this fact
affords us a very striking object-lesson on the way in which an offensive or
merely defensive development in one organism may lead to the very con-
siderable adaptation in some other organism that may ba seriously affected
by it. The three caterpillars named have developed protecting spines
which keep the stinging hairs of the Nettle from contact with their tender
skins. Their relative, Pymmeis cardui, which feeds on Thistles, is similarly
protected. It is remarkable that, so far as we have read, botanical writers
have failed to note that hairs similar to those of the Nettle, but in a far
FIG. 373. — NAIL-GALLS
On leaf of Lime, produced by a r
Photo by] 1E-
FIG. 374. — Primula clccnica.
This bai'atiful plint is coverei with easily detachable hairs. If these, by incautious handling, come in contact
witli the hum in skin, they set up an inaimmitioa very similar to eczemi, for which it has been often mis
-^ 307
308
HUTCHINSON'S POPULAR BOTANY
less highly developed condi-
tion, are found on the leaves
and young twigs of the Com-
mon Elm (Ulmus campestris}.
They are abundant along the
•j^t —pr • ^^^fr: midrib on the lower surface,
" f^\ / - £' and though they have nothing
M' I . "^^ 1|| like the malignity of the Nettle,
^rfjpy *'". ^i^fMi ^ej canse a considerable
^•8= LV^. 1 ^ amount of irritation to the
hands and wrists of those who
touch the leaves. The Elm
sends up numerous suckers,
and all down the bole it t}irows
out new shoots, which would
be probably browsed off but
for the presence of these hairs.
The Elm belongs to the same
natural order (Urticacese) as the
Nettle.
When investigation has
been carried farther it will be
shown probably that the hair-
structures of many other plants
have a protective purpose.
Many species of Mullein (Ver-
bascum), for example, have
branched radiating hairs which rub off easily when the plant is handled,
and, though not stiff or prickly, "remain hanging to the smallest in-
equalities on the surface of the disturbing body. If grazing animals
bring the mucous membrane of their mouths into contact with the leaves
of the Mullein," the Hock-like masses of hair adhere to the tongue and
palate and produce sensations that can hardly be pleasant (Kerner). The
hairs of several species of Primula, also (notably P. obconica), set up an
inflammation very like eczema when handled incautiously.
It may not be generally known that the singular growths called galls,
so often to be seen on the leaves and branches of Flowering Plants, are
due to insects. Formerly they were held to be entirely of a vegetable
nature, and the insects found in them were thought to have been spon-
taneously generated there. Many species of Cynips lay their eggs in the
parts named, plunging their exceedingly delicate ovipositors into the soft
tissues, and thereby set up local irritation, which induces a responsive
action of the protoplasm, and galls are produced. In some cases, how-
ever, the development of the gall does not commence until after the egg is
Photo by}
FIG. 375. — SPIKED PEA-GALL,
On Dog-rose, caused by the gall-wasp, Rhodite,
THE LEAF IN RELATION TO ITS ENVIRONMENT
309
hatched. No tree, probably, furnishes so great a variety of these growths
as the Oak (Quercus), on which upwards of one hundred and fifty species have
been observed, the well-known oak-apple being one of them. It is pro-
duced by the punctures of Dryoteras tenninalis. Two species of Oak-gall
often to be met with are produced by an insect named Spathegaster bac-
carum. Fig. 373 represents a leaf of a species of Lime (TUia platyphyllos)
with little conical excrescences or nail-galls, the work of a microscopic
species of Phytoptus (P. tilce), whose portrait you will notice just above
the leaf. Similar galls, but of a downy nature, occur on the leaves of
Beech (Fagus sylvatica], in this case caused by a two-winged fly (Hormomyia
piliger). The green (ultimately red), mossy-looking growths called bede-
guars, or Robin Redbreast's Pincushion, so common on branches of the
Rose, are also of insect origin (fig. 371). The gall-fly (Rhodites rosea)
deposits its eggs in the shoot-bud, which presently swells and begins to
put out what should be in the natural course three leaves : but embryo
leaves have so little parenchyma between their veins that they fall into
threads and thus give the mossy appearance to the galls. On cutting
open one of the bedeguars the larvae of the insect will be found in the
centre. In all these cases it appears that only the cells of the meristem can
give rise to the galls. These growths do not appear to be actually injurious.
The galls that are
found on Hedge Bed-
straw (Galium mollugo)
are produced by a
minute two-winged fly
(Cecidomyia aparine) ;
and the many-cham-
bered gall on young
shoots of Spruce (Picea
excelsa), that look like
half a pine cone, are
the work of a Coccus
(Kermes). The "Witches
Broom " on the Scots
Pine (Pimis sylvestris) is
an excrescence consist-
ing of a multitude of
short shoots produced
by a fungus (Perider-
mium elatinum).
What is known as
fasciation, or the fusing
together of parts of a
plant which are norm-
Photo by] \-E-
FIG. 376.— "WITCHES BROOM " ON SCOTS PINE,
Caused by the fungus Peridermium elatinum.
310
HUTCHINSON'S POPULAR BOTANY
ally distinct, as in the triple flower of Fuchsia shown in fig. 377, is
likewise (at least, in a large number of instances) due to gall-mites.
Many of the singular metamorphoses of plant organs, too — floral leaves
which are changed into foliage leaves, petals which become stamens, etc.,
etc. — are probably attributable to the same exciting cause — a subject of
which we shall have more to say when speaking of the Flower.
In some instances galls have a positive economic value, though this, of
course, is of no advantage to the plant.
The galls of commerce are chiefly those
which occur on Quercus infectoria, and the
best of them come from Aleppo and
Smyrna. They yield a fine black colour
with any of the salts of iron, and are
largely used in the manufacture of writing-
ink. Perhaps the most dreaded of gall-
producing insects is the grape-louse (Phyl-
loxera vastatrix), which pierces with its
proboscis the young leaves and roots of
the European Vine ( Vitis vinifera), and
thereby causes the growths referred to.
The galls, by driving away nourishment
from the roots (in which they are ably
assisted by the insects themselves), starve
and weaken those delicate organs, and at
last destroy the plant.
We have now touched upon all the
more important facts connected with the
forms, structure, and functions of foliage
leaves, and with the means provided by
Nature for their protection and preserva-
tion. A few remarks on the decay and fall
of the leaf may fitly conclude the subject.
One of the first external signs of incipient decay in green leaves is
the fading of their freshness. The green becomes dull, and gradually
assumes a yellow, brown, or ruddy tinge, due to varying degrees of oxida-
tion of the chlorophyll, contained in the cells.
The fall of the leaf is not primarily nor necessarily due to external
forces. Wind and frost may, and do, perform their part, but long before
the leaf has attained its full growth and vigour the busy protoplasts have
been weaving a layer of cells, which shall infallibly ensure the work of
disarticulation. These cells, botanically known as the layer of separation,
are formed in the base of the leaf-stalk, and run at right angles to the
older and displaced cells, so that they divide the leaf from its branch or stem.
FIG. 377.— FUCHSIA.
Monster flower caused by fasciation.
Photo by}
IHenry Irving.
FIG. 378. — " OAK-APPLE " (GALLS OF Dryoteras terminalis).
About cwo-thirds of the natural size. They are found in May and June on the twigs of the Oak, ar
numerous larvae are embedded in the soft tissue of the green- and red-skinned " apple."
311
CHAPTER XI
FLORAL FORMS AND THEIR RELATIONS TO INSECTS
To me the meanest flower that blows does bring
Thoughts that do often lie too deep for tears.
WORDSWORTH.
AS there is a good deal of ground to be covered iu this chapter, we will
not waste time on the threshold. Our subject is the Flower — in
many respects the most important, as certainly it is the most interesting, of
the subjects of which Botany treats. The Flower contains the organs of
reproduction, a fact which accounts for its pre-eminent importance : while
the manner in which those organs discharge their appointed functions —
assisted often by the most unlikely agencies,
as water, wind, and insects — gives to the
study of the Flower an attractiveness all
its own. Root, stem, and leaf are not with-
out their fascinations, too, as we have
sought to show in earlier chapters, but the
Flower is the part of the plant which
rightfully commands the lion's share of
interest.
As with the leaf, the beginning of the
Flower is the bud. Flower-buds originate
in much the same way as leaf-buds, and
cannot be distinguished from the latter in
their earlier stage. Like leaf-buds, too,
they are formed either in the axils or at
the ends of branches, and in accordance
with those conditions are named respec-
tively axillary and terminal.
The reader will probably recognize the
little flower shown in fig. 379. It is the
Moneywort or Creeping Loosestrife (Lysi-
machia nummulama), an English wild-
flower partial to ruins and damp woods,
and a favourite rockery plant under culti-
vation. It, and its near relation, the Wood-
312
FIG. 379. — CREEPING LOOSESTRIFE.
An example of solitary and axillary flowers.
FLORAL FORMS AND THEIR RELATIONS TO INSECTS 313
land Loosestrife or
Yellow Pimpernel, offer
familiar examples of a
solitary and axillary
flower. The Herb-paris
(P. quadrifolia, fig. 381)
bears solitary flowers,
too, but they are ter-
minal, not axillary. The
Herb-paris is one of the
most singular of our
wild-flowers, and, like
the Loosestrifes, delights
in moist and shady
woods.
But solitary flowers,
whether axillary or ter-
minal, are the exception
rather than the rule.
In by far the greater
number of plants the
bud unfoldsinto a branch
system, consisting of
several flowers, which
are known collectively
as the inflorescence. The
Cowslip (Primula veris),
Cherry (Prunus cerasus),
and Forget-me-not (Myo-
sotis palustris) may serve
as examples. What is
popularly known as the
"flower" of the Daisy
(Bellis perennis) and
Dandelion (Taraxacum
officinale) is likewise an inflorescence ; each of the so-called flowers being
really a multitude of minute flowers (florets) crowded together on a single
stem. We will consider the structure of one of these composite flowers
later on.
In describing a flower the presence or absence of a stalk should always
be noted. Stalkless or sessile flowers are comparatively rare, but the flower-
stems of stalked or pedicellate flowers may be so short as to be hardly
perceptible. No more remarkable instance of a sessile flower could be
named than that vegetable wonder, Rafilesia arnoldi, of which some account
Photo by] [E. Step.
FIG. 380. — CUCKOO-PINT (Arum maculatum).
The front part of the spathe has been cut away to show the minute flowers
around the base of the spadix.
314 HUTCHINSON'S POPULAR BOTANY
was given in a former chapter ; and if we place side by side with Rafflesia
the stalked inflorescence of the celebrated Lilium giganteum, we have a
contrast indeed. A flower-stem of one of these Lilies, cut from a living
plant in the Sunningdale Nursery in July, 1879, is preserved in No. 1
Museum at Kew. The circumference of the pedicel is eleven and a half
inches, its height thirteen feet ! Truly a Brobdingriagian flower-stem.
A stalk which supports a solitary flower, or the primary stalk of an
inflorescence, is called a peduncle; while the branches or secondary stalks
are known as pedicels. The stalk of Herb-paris, one of the flowers that we
were looking at a moment ago, is an example of a peduncle ; so is the
primary stalk of the Lily of the Valley (Convallaria majcdis), while its
slender branches, curving with the weight of the dainty little bells, are
pedicels. The portion of the floral stem (peduncle) which, in this plant,
bears the stalked flowers, is the rachis. Rachis is the Greek word for
" spine," and besides being the term
used in anatomical science for the
vertebral column of animals, is used
for many things which suggest a
resemblance to the spine, as the shaft
of a feather, the stalk of the frond in
Ferns, the axis of a compound leaf,
and (as we have just seen) the axis of
an inflorescence.
The Lily of the Valley is an ex-
tremely useful plant for an object-
lesson. Who is not familiar with its
pensile beauty? It is a favourite
FlG 381 HERB-PARIS flower under cultivation, and one of
Solitary and terminal flower. the HlOSt SOUgllt after of wild-flowers.
The plant needs some seeking, too,
for it loves to hide from sight in shady glens, covering its nodding white
bells with its large and glossy leaves.
You perceive that the leafless peduncle springs directly from a sub-
terranean stem or root-stock — a rhizome, to use the botanical term. On
this account the inflorescence is called a scape, and the plant itself a
scapigerous herb. The Primrose, Cowslip, and Oxlip (Primula vulgaris, P. veris,
and P. elatior) also offer familiar examples of scapigerous herbs.
Notice, further, that the pedicels of the Lily of the Valley spring from
the axils of what appear to be minute leaves — a fact of importance, as
similar leaf-like forms are found on most branched inflorescences. They
are called bracts, from the Latin bractea, a thin plate of metal. Bracts are
usually green, but in certain plants — as the Flowering Dogwood (Gornus
florida) and the celebrated Edelweiss (Leontopodium alpinum) — they are white
or coloured like the petals of flowers, and are then called petaloid. In Poinsettia
FIG. 382. — COWSLIP (Primula veris).
A. familiar plant whose nodding yellow flowers are borne in an umbel on a tall scape, hence it is described
a scapigerous herb. EUROPE, w. ASIA, N. AFRICA.
315
316
HUTCHINSON'S POPULAR BOTANY
they form the most showy
portion of the inflorescence,
theflowers themselves being-
small and inconspicuous.
The names bracteate and
ebracteate are applied to
flowers according as they
possess or do not possess
these modified leaves.
Here is a flower that
will be readily recognized
(fig. 380). No lover of
green lanes and sunny
meadows bordering banks
can be a stranger to the
Cuckoo-pint or Wake
Robin (Arum maculatum),
with its " ear-like spindling
flowers,'' as Clare calls
them, " betinged with
yellowish, white, or purplish
hue." But let us be clear as
to what we are looking at.
The figure does not represent a single flower, but an inflorescence, the numerous
flowers of which are congregated round the narrow lower part of the club-
like column or spa.*.)• (The keel, wings, and
standard have been removed.)
of what has been before us in this
rapid sketch. The process that
has been described is the same, in
all essential particulars, as that
which goes on in the great majority
of flowering plants, and it is so
simple as to be easily understood.
The pollen may be conveyed to
the stigma by other than insect
agency, and the tubes may pursue
a more winding course through
the conducting tissue ; but these
are details, and the above descrip-
tion may be accepted as a fairly
representative one. What actu-
ally takes place in the ovules when
the pollen-tubes have found an
entrance will be explained farther
on (Chap. XIV.) : it is sufficient
here to have directed attention to
the fact itself. The growth of the tubes may be conveniently demon-
strated with the pollen of the cultivated varieties of Caladium, all that
is needed being to leave a few grains on a damp microscope slide for five or
six hours.
We have already seen that the beginning of the flower is, like the
beginning of the leaf, the bud ; and that a flower-bud and a foliage-bud are
indistinguishable in the early stages of growth. The theory of the develop-
ment of all parts of the flower from
leaves was enunciated by the poet
Goethe nearly a century ago : and
though the announcement of his
discovery was accompanied by a
good deal of speculation which
subsequent research has shown to
be erroneous, his main position had
much to recommend it. nor does it
lack defenders even at the present
day. Goethe taught that " the
elementary floret expands into a
leaf upon the stem, contracts to
make the calyx, expands again to
make the petal, to contract again
FIG. 394. — ABNORMAL FLOWER OF Begonia, into sexual Organs, and expand for
With sepals developed a? green foliage leaves. the last time illtO fruit."
FLORAL FORMS AND THEIR RELATIONS TO INSECTS 325
On the other hand, there are physiologists of the first rank who hold
the theory of the German poet in light esteem, and to whom the pronounce-
ment that " every flower is simply a metamorphosed leaf-shoot " is a
dangerous expression, implying that the flower has been developed in
course of evolution from a leaf-shoot, for which, in their judgment, there
is not sufficient evidence. We are disposed to concur in this view, and
rather than yield allegiance too readily to G-oethe's theory would say
Photo by} [E. Step.
FIG. 395. — LAKGE-FLOWERED ST. JOHN'S WORT (Hypericum calycinum).
Rose of Sharon. The lar
re flov
form
:rs offer good examples of spiral activation. The profuse stamens
number of little bundles.
that there are flower-shoots and leaf-shoots, without attempting to derive
one from the other.
Yet the tendency of the floral organs to relapse into the foliar form in
certain abnormally developed flowers, at least confirms the idea that floral
leaves and foliage leaves are homologous structures.
Most of us, doubtless, have met with flowers of the kind referred to —
" monstrous " flowers, as they are called. In Science Gossip (1890) there
is an interesting series of papers on the subject, by Dr. J. E. Taylor, with
drawings of some of the more remarkable monstrosities. In one place
we find an abnormal Knapweed (Gentaurea nigra}, of which some of the
florets have become leaf- like; in another, a Daisy (Bell is perennis) has
326 HUTCHINSON'S POPULAR BOTANY
developed a true foliage leaf instead of a bract in the involucre. A third
specimen (a flower of the Enchanters Nightshade— Circcea lutetiana]
appears with a portion of its stigma transformed into the anther of a
stamen, and a stamen assuming the character of a pstal, while, in place
of another of its petals, two sepals are developed! Not less remarkable
is the figure of a Peach-flower, whose organs exhibit a steady gradation
from petals to foliage leaves : and farther on in the volume we meet with
an abnormal Rose, entirely devoid of petals, and with sepals which seem
to have been trying ard to produce a serrated margin. The stamens
of this flower are normally developed,
but the pistil (if pistil it may be called)
is a curiosity, the style being elongated
into a green and healthy-looking shoot.
bearing some two or three dozen ordin-
ary leaves !
The " monster " flowers which have
come under our own notice are not
so singular as those figured in Dr.
Taylor's remarkable articles, but they
serve no less to illustrate Goethe's
law. The first figure (fig. 393) repre-
sents a flower of Wistaria, from which
the coloured petals have been removed.
In this example the abnormally de-
veloped organs are the stamens, one
of which has a small leaf-shaped
purple petal growing out from the
centre of the style ; while another
has developed a similar petaloid
organ in place of the anther-lobes.
In the second figure (fig. 394) we
have a "monstrous" flower of Begonia
(B. octavia], whose outer petals — or
rather sepals— have been metamor-
phosed into green leaves, with midrib, veins, etc.
In many species of the genus Clematis, the sepals are petaloid — that
is to say, they are coloured like true petals, while the petals are absent.
The former are spoken of collectively as the perianth, this being the name
applied to the floral envelopes of a flower when calyx and corolla are not
easily distinguished. It would be well, perhaps, to keep exclusively to
this use of the term, rather than apply it in a loose way to the floral
envelopes of any and every flower. In the figure of Clematis ccerulea
(fig. 398), the six petal-like organs (really sepals) constitute the perianth.
Probably no flower better illustrates the truth we are considering than
FIG. 396. — SNAPDRAGON.
A portion of the stigma and style, showing pollen-
grains on the former putting forth tubes and pene-
trating the style.
FIG. 397. — DEFINITE INFLORESCENCES.
(a) Panicled cyme of Chinese Privet (Ligustrum luddum). (b) Corymbose cyme of Di _
(c) Fascicle of Sweet-william (Dianthus barbatus). (d) Scorpioid cyme of Forget-me-not (My „„,-,,.,„,„-,)
© Glomerulus of Box (Buxus sempermrem). (/) Verticillaster of Yellow Archangel (Laminm galeo
327
328
HUTCHINSON'S POPULAR BOTANY
the "White Water-lily (Nymphona alba\ in which the gradual stages of
transformation from the green sepals of the calyx to the yellow pollen-
producing stamens may be seen to great advantage. We are not speaking
now of '; monstrous " specimens of the flower (nor were the Begonia and
Clematis last alluded to at all abnormal), but of the ordinary White Water-
lily ; which thus shows, in a permanent fashion, the community which
exists between the various members of the flower. For the sepals merge
into petals, and the petals into stamens, by such imperceptible gradations
that at certain points it is difficult to say to what set of organs particular
parts belong. In drawings made to illustrate the fact, it is easy enough to
see that one figure with its dark green colouring is a sepal, and that a second,
though of a paler green, is probably a sepal too; but what of the next
figure ? This is neither
a decided green nor a
pure white, but a cross
between the two, and
it might be called in-
differently a sepal or a
petal. In the next row
we have petals beyond
a doubt ; but we are
again at a loss when we
come to another row.
Do these organs repre-
sent petals or stamens ?
They are broad and
white like the former
row, but the thickening
at their apex is of a
3Tellow colour, and has
all the appearance of
rudimentary anther-
lobes. The figure beside it is equally perplexing, and not till we get far
in do we find a stamen pure and simple, with normally developed style
and anther and abundance of pollen. The transition is far more
gradual than the description might lead one to suppose. In the flower
itself a large number of petaloid sepals and stameniferous petals have
place between the organs named; and each differs in some slight
degree from its neighbour. Here, then, you have an abiding witness to
the facts of which we have been treating — a constantly accessible illustration
of that homology of structure which seems to exist between the members
of every flower. We are now in a position to carry our inquiry a step
farther.
A flower being only a modified shoot, it is not surprising that the
Fio. 398. — FLOWER OF Clematis ccerulea,
With petaloid sepals.
FLORAL FORMS AND THEIR RELATIONS TO INSECTS 329
/
FIG. 399. — ESTIVATION OF FLOWERS.
(a) Valvate. (6) Imbricate, (r) Contorted or
twisted. () Quincuncial. (/) Vexillary.
arrangement of rudi-
mentary floral organs
in the bud is analogous
to the arrangement of
young foliage leaves :
and therefore that
what has been already
said on the subject of
prefoliation. or vernation, applies almost
equally to the subject of preparation, or
aestivation. The word " aestivation " is
derived from the Latin cestas, summer,
this being the season when most flowers
begin to open, just as " vernation '' is
derived from the Latin ver, the season
specially associated with the expanding
of leaf-buds. Moreover, the terms which
are employed in describing the various
modifications in the one, answer almost equally for the other : though
flower-buds exhibit certain arrangements which are peculiar, and for which
special terms have had to be invented.
It is sufficient here to observe that
all the various modifications may be ar-
ranged under two heads, the circular and
the imbricated or spiral. The former
comprehends those varieties in which the
component parts of the whorl (the sepals
of the calyx, petals of the corolla, and so
forth) are arranged in a circle and nearly
on the same level ; and the latter includes
those forms in which the said parts over-
lap one another, and have a more or less
spiral arrangement, the consequence of
their being placed at slightly different
levels. For interesting varieties of circu-
lar aestivation the calyx of the flower-buds
of the Lime (Tilia) and Hollyhock (Altkcea
rosea) and the folded corolla of the Potato
(Solanum tuberosum) may be profitably
examined; while the Camellia, Rose, Bind-
weed (Convolvulus), Snapdragon (Antir-
rhinum), and St. John's Wort (Hypericum)
offer examples of the chief varieties of
spiral aestivation (figs. 395 and 399). (C> uguiate corona.
FIG. 400.— FLORET OF DANDELION.
(a) Cohering anthers, (ft) Extremity of style.
330
HUTCHINSON'S POPULAR BOTANY
We approach more interesting ground when we begin to speak of the
expanded flower. The question of form and arrangement again meets us
on the threshold, but the study of the structural variations of flowers by
no means confines one to the acquisition of name -lists or to tedious and
meagre definitions. The question is one of scientific importance, involving
as a preliminary step the arrangement of multitudes of appearances under
primary points of view, and their classification according to rule and
exception ; by which means alone a discovery of the actual laws of Nature
is rendered possible. Now, manifold as are the structural arrangements
of flowers, the variations really concern only a few simple subjects, and
when these are grasped the investigation of the causes which produce
the differences in the whole floral world is by no means a hopeless under-
taking (Schleiden).
The subjects of variation are, in fact, four; and
the first to be mentioned is number. A Lily, for
example, has three sepals, three petals, and six
(i.e. twice three) stamens ; while its pistil, though
looking like a single organ, is really made up of
three carpels which have grown together. The
Lily belongs to the great class of Monocotyledons,
and three may be said to be the characteristic
number of that class. In the floral whorls of
Dicotyledons, on the other hand, threes are a
rarity ; nor can any number be said to be charac-
teristic, though fours and fives are very common.
A Fuchsia has four coloured sepals, four petals,
twice four (i.e. eight) stamens, and four carpels.
A flower of Cherry, on the other hand, has its
two outer whorls, the calyx and corolla, in fives,
and its stamens form a multiple of five — namely,
twenty. The ovary does not follow the rule — it is solitary ; nor is this case
by any means an exceptional one, the parts of the pistil in the majority
of Dicotyledons being fewer than in the other whorls.
It might easily be shown that whorls of flowers correspond to cycles
of leaves, but it would be exceeding our present limits to push our inquiries
farther in this direction.
The second of the four subjects of variation is cohesion. This term is
applied by botanists to the union of like parts in a flower, as of sepal with
sepal, petal with petal, stamen with stamen, and so forth. Both the calyx
and corolla of a Primrose are good examples of cohesion. Here the five
sepals unite in a tube and form what is called a gamosepcdoiis calyx ; the five
petals are also fused together, and so the corolla is described as gamopetalous.
A calyx whose sepals are not united is said to be polysepalous ; a corolla
with separate petals is polypetalous. In the Laburnum (L. vidgare) the fila-
FIG. 401. — COMMON PEA.
A carpel with seeds removed.
FIG. 402. — INDEFINITE INFLORESCENCES.
(a) Cone of Larch (Larix europea). (6) Umbel of Cowslip (Primula i-eris). (<-) Strobile of Hop (Humulus lupulus).
(rf) Hjrpanthodium of Fi* (Ficus carica). (*) Panicle of a Yuow. (/) Thyrsus of Horse chestnut (.isculus
hippotaslanum). (g) Capitulum of Corn Blue-bottle (Centaurea cyanus). (h) Catkin of Hazel (Corylm avdlana).
(0 Corymb of Cherry (Cmu) petals,
(e) calyx, (r) receptacle.
•*.< -»,
/'* V-
FIG. 414. — GARDEN LARKSPUR (Delphinium exaltatum).
A beautiful North American plant much grown in gardens, where crossing and selection have produced many varieties.
The showiness of the flower is due to the sepals, the petals being reduced to two small nectaries, the dark centre
of the flower in the photograph.
339
340
HUTCHINSON'S POPULAR BOTANY
FIG. 415. — HONESTY
(Lunaria).
Section of flower showing saccatt
calyx.
In contrast to the Wallflower, take a Pansy
(Viola"). A Pansy is a good example of an irre:/"f"r
flower. By cutting through the centre perpen-
dicularly we get two similar halves, but in no
other way can the flower be divided symrne trie-
ally. Flowers exhibiting this kind of bilateral
symmetry are known as monosymmetrical or zyyo-
morphic (Greek zeugnumi, I join, and morphe, a
shape). Flowers the petals of which are placed
like the spokes of a wheel, and which may there-
fore be divided vertically into similar halves
through two or more planes, are termed actinomor-
phic (Greek aktin. a spurious form of aktis. a ray,
and morphe]. All regular flowers are actinomor-
phic : most irregular flowers are zygomorphic.
Some flowers cannot be symmetrically divided in
any plane — they are asymmetric.
There is a curious fact about the Pans}'. What appears to be the lower-
most petal is really the upper, for the flower has been reversed. It has been
thought that the purpose of the curve in the flower-stalk is to strengthen
the flower and thus to enable it to sustain the weight of insects. When
a honey-bee visits a Pansy, it almost always turns round on alighting, and
sucks with its head downwards, and the flower is bent down by the insect's
weight — a circumstance which indirectly bears out this idea. Notice the
streaks of colour on the petals, all leading towards the centre of the flower.
They are honey-guides for the insect visitors — pathfinders, as some have
named them. There will be more to say about
these pathfinders on a future occasion, but allusion
is made to them here by way of emphasizing the
contrast which the petals of this flower present to
those of another common flower, the White Cam-
pion i Lychnis vespertina, fig. 416). The pure white
corolla of this species of Campion has no guiding
marks : in this case they would be of no service,
for the flower expands in the evening, and insects
are attracted to it by its whiteness. There are
five petals, attached by claws to the base of a
tubular calyx, and these are the characteristic fea-
tures of a caryophyllaceous corolla. The Maiden
Pink (Dianthus deltoides). Carnation (D. caryophyl-
lus}: and Catchfly (Silene) exhibit the same features.
The rosaceous corolla consists of five petals, too,
but the}- are without claws : the Buttercup (Ra-
nunculus, fig. 419) is a good example.
FIG. 416. — WHITE CAMPIOX
(Lychnis vespertina),
With styles exserted.
FLORAL FORMS AND THEIR RELATIONS TO INSECTS 311
FIG. 417. — WINTER CHERRY
(Physalis),
Showing the accrescent calyx.
Notice how the corolla of the White Cam-
pion is constricted near its upper end by the
toothed or dentate calyx. This is another con-
trivance for shutting out unwelcome visitors.
Only a thin proboscis, at least three-fifths of an
inch long (such, for instance, as that of the Small
Elephant Hawk-moth (Chcerocampa porcellus],
which often visits and cross-pollinates the flower),
could reach to the fleshy part of the ovary where
the honey is stored. In fact, both the calyx-
tube and the elongated claws of the petals assist
in preserving the nectar for those insects whose
visits are really serviceable to the plant. In
flowers with salver-shaped (kypocrateriform)
corollas, like the Primrose and Common Lilac
(Syringa vulgaris), the tubes formed by the
cohering petals answer much the same purpose as the clawed bases of
caryophyllaceous corollas, and also protect the pollen from drops of rain
and dew — the latter an important consideration in the case of plants
which dwell amid mountain-mists, like the delicate species of Primulacese
belonging to the genus Androsace, and many species of Phlox (fig. 421).
"If flowers of Aretia glacialis, a plant growing on the moraines of glaciers,
are examined after a shower," says Kerner, " it is found that every one has
a drop resting upon it which slightly compresses
the air in the narrow tube of the corolla, but
cannot reach the pollen upon the anthers lower
down the tube. A subsequent shake or puff of
wind causes the drops to roll off the limb of the
corolla, or else they are got rid of by evapora-
tion ; in either case, the flower becomes once more
accessible to insects." Salver-shaped corollas
must be distinguished from rotate or wheel-
shaped corollas, such as we get, for instance,
in purple-flowered Woody Nightshade (Solanum
dulcamara). In the former the tubes are long
and narrow, in the latter they are short ; but in
both the limb is placed at right angles to the tube.
We come now to the tubular corolla. From
what has been said about the uses of caryophyl-
laceous and salver-shaped corollas, the purpose of
this third form may be readily divined. It, also,
has reference to insect-pollination. The Com-
mon Honeysuckle (Lonicera peryclymenum) may
serve as an example. The sweet-scented flowers
FIG. 418. — GREAT VALERIAN
( Valeriana officinalis).
Showing the gibbous corolla.
342 HUTCHINSON'S POPULAR BOTANY
are adapted for fertilization exclusively by long-tongued crepuscular and
nocturnal moths ; and why ? Because the wax-like tubes are long and
narrow — too long for short-tongued insects to reach the honey while
standing at the mouth of the flower, and too narrow to enable them to
descend bodily to the nectary. As a matter of fact, the flowers bloom at
the very season when hawk-moths are most abundant — that is, during Ma}*
and June — and they exhale their perfume most strongly in the evening,
when these moths are on the wing.
Another form of gamopetalous corolla which must not be passed over
is that which, from its resemblance to a funnel, has received the name
infundibuliform. The name is less elegant than the flower to which it
is applied. The delicate white chalices of our beautiful Hedge Convolvulus
(C. sepium) are of this form. Funnel-shaped flowers have not such a
reputation for exclusiveness as have those
of tubular and salver shape ; and it has been
{^ rX observed of the Hedge Convolvulus that
PP|jk\ all sorts of thrips and little flies frequent
•L, ^ ^ the flowers by day, sheltering and feeding
there, though they confer no benefit in
return. Only on bright, moonlight nights,
when the sphinx-moths are about, does the
plant reap any advantage from its visitors.
A friend of the naturalist Delpino, standing
by a hedge overgrown with this Bindweed,
was able to capture numbers of one species
of sphinx-moth (S. convolvuli) simply by
closing with finger and thumb the orifices
FIG. 419.— ROSACEOUS COROLLA of the flowers as the moths inserted -their
OF A BUTTERCUP. heads.
A form of corolla closely related to the
infundibuliform is the campanudate, or bell-shaped. We have examples
of a regular campanulate flower in the Rampion (Campanula rapunculvs,
fig. 426) and other Bell-flowers, and of an irreguJ.ar or oblique campanulate
flower in the equally well-known Foxglove (Digitalis, fig. 420 1. The wide
bell-shaped corollas of Campanula are specially adapted for humble-bees ;
but the flowers number other kinds of bees among their visitors, and
numberless beetles and small flies use them as shelters from the rain or
make the comfortable bells their night quarters. The Foxglove is also
specially adapted for humble-bees, for, says Hermann Miiller. " no other
insects are large enough to touch the stigma and anthers with their backs
when creeping into the tube." They are, in fact, the only pollinators of
the Foxglove. Possibly the enlargement of the under side of the corolla,
which gives the irregularity to the flower, is intended as a landing-stage
for the insect (it is certainly so used), and may also be an arrangement
\
\_E. Step.
FIG. 420. — FOXGLOVE (Digitalis purpurea),
With obliquely bell-shaped corollas which can be pollinated only by humble-bees, for whie
specially adapted The lip on the lower side forms an alighting platform from wuicn me
right into the bell. WESTERS EUROPE.
343
344
HUTCHINSON'S POPULAR BOTANY
to relieve the strain upon that part of
the bell where the weight of the humble-
bee presses most.
We find ourselves among flowers of
more intricate construction when we
come to speak of labiate or lipped
corollas. The White Dead-nettle
(Lamium album}, one of the commonest
of our weeds, is the flower chosen for
illustration (fig. 425). The corolla is
decidedly irregular, and on a cursory
examination it is not easy to distin-
guish from one another the five coher-
ing petals which compose it; though
by bearing in mind the simple rule
that petals should alternate with sepals,
the difficulty will vanish. Guided by
this rule it will be found that the
lower lip or cleft piece in front is one
petal, that the pointed and inconspicuous
FIG. 421,-MossY PINK (Phlox subulata), appendages on either side the corolla-
With salver-shaped corollas. ° ,, ,. „ ,
tube are the rudiments ot two more,
and that the remaining pair form the overshadowing hood or upper lip
of the flower. "We can estimate by direct observation," says Hermann
Miiller, "how perfect the adaptation of this flower is to bees' [humble-
or other large bees'] visits. The bee alights on the under lip, and in
doing so thrusts its head between the broad lateral lobes of the mouth,
clings with its fore feet to the base of the under lip, and with its inid-
and hind-feet to the two lobes of the under lip; then if its proboscis is
not less than ten millimetres [about two-fifths of an inch] long, it can at
once reach the base of the flower. While sucking, the thorax, and in
the case of small workers the base
of the abdomen also, fills up the
space between the upper and lower
lips, and the vaulted upper lip fits
the bee's back, which is pressed
against the stigma and the open
face of the anther."
Personate or mask-like corollas,
of which the Toadflax (Linaria)
and Snapdragon (Antirrhinum^)
offer convenient examples, are even
more elaborate in their construction
than the labiate form. They re-
FIG. 422. — WHORTLE-
BERRY (Vaccinium).
TJrceolate corolla.
FIG. 423.— GRAPE-
VINE (Vitis).
ilitMBform corolla.
FLORAL FORMS AND THEIR RELATIONS TO INSECTS 345
semble the latter in possessing a double lip, the essential point of difference
being that their lower lips approximate to the upper, so as to close the orifice
of the tube or throat. In the Toadflax (fig. 429) this arrangement shuts out
flies and beetles, which lack the requisite strength to force an entrance,
while the length of the nectar-storing spur excludes short-lipped bees, which
are not so incapable of breaking in. Thus the flowers become exclusively
adapted for the long-tongued species, by which, indeed, they are diligently
visited. The Toadflax, it may be noted in passing, is one of those flowers
which, though normally irregular, will sometimes become regular by
producing in all
their petals or
sepals the very fea-
ture which is the
cause of their ir-
regularity. In the
flower in question,
the peculiarity is
that each of the
five petals, by vir-
tue of this excess
of irregularity, pro-
duces a spur, while
the upper part of
the flower loses its
personate character §p^ \\ ^/8S2K
and becomes regu- ki^3it<: ~'t$l
lar. The wonder '-«**
excited in the mind
of the great Linnaeus
by this phenomenon
led him to apply to
it the name pelovia,
from the Greek word
peloron, a monster.
Of course, in a
normally and regular^ spurred corolla, like the Columbine (Aquilegia
vidgaris, fig. 427), the term " peloria " would not be applicable.
The arrangement in the personate corolla of the Snapdragon is similar
to that of Toadflax, though not identical. Here, as there is no spur to
keep off smaller bee-intruders, the entrance is more firmly closed, and it
is only when the flower is old and beginning to wither that it opens
its door to such visitors. The flower is, indeed (to quote Lord Avebury),
" a strong box of which the humble-bee only has the key." This guard-
ing of the entrance is a necessary precaution, for if flies and small
Photo by] [E. Step.
FIG. 424. — SEASIDE CONVOLVULUS (Convolvulus soldanella),
With funnel-shaped pink flowers. The leaves are small, heart-shaped or kidney-
shaped, and the stem rarely twines.
346
HUTCHINSOX'S POPULAR BOTANY
bees were admitted from the first they would simply pilfer all the hone}',
and the flower would be less diligently visited by its chief pollinators,
the humble-bees. Ants and small flies, however, will often squeeze
their way in, their great difficulty being rather how to get out than
how to gain an entrance — a circumstance referred to by Mr. Knapp in his
charming Journal of a Naturalist. "It has not perhaps been generally
observed," he writes, ''that the flowers of this plant— ' bulldogs,' as the
boys call them — are perfect insect traps : multitudes of small creatures
seek an entrance into the corolla through the closed lips, which upon a
slight pressure yield a passage, attracted by the sweet liquor that is found
at the base of the germen [ovary]; but when
so admitted, there is no return ; the lips are
closed, and all advance to them is impeded by a
dense thicket of woolly matter, which invests
the mouth of the lower jaw.
Smooth lies the road to Pluto's gloomy shade ;
But 'tis a long unconquerable pain
To climb to these ethereal realms again.
But the Snapdragon is more merciful than most
of our insect traps. The creature receives no
injmy when in confinement ; but, having con-
sumed the nectareous liquor, and finding no
^^ egress, breaks from its dungeon by gnawing a
^^K hole at the base of the tube, and returns to
" ^^L^ liberty and light."
This last statement is evidently a mistake.
S^B^t"X^ ^r- Knapp is probably referring to the neat
m^^ ^^^-_ round hole which is made by certain short-
tongued bees from without, to enable them to
reach the nectar and nullify the flower's pre-
cautions for their exclusion.
The wood-ant (Formica rufa) is a common
plunderer of the flower, but, as already re-
marked, its chief pollinators are humble-bees, which do no injury to their
host, and leave by the door they enter at. "It is most interesting to
observe," writes Kerner, " how a humble-bee buzzes about till it alights
on the two knobs of the lower lip, and then, having opened the mouth
by means of hinges on either side of the corolla, suddenly disappears into
the cavity of the flower to fetch honey. In the Calceolarias," continues
this writer, " the phenomenon is even more remarkable. The humble-bee
sits on the inflated, slipper-like lower lip, and opens the mouth by a light
pressure against the upper lip. Then a nectary, hitherto hidden in the
slipper-like cavity, comes to light, flap-like, and amply provided with
FIG. 425. — WHITE DEAD-
NETTLE (Lamium album).
The two-lipped calyx is also shown
separately (lower fisure).
Photo by]
FIG. 426. — RA.MPIOK (Campanula rapunculus],
A rare wild-flower that may be mistaken at sii?ht for the Hire-bell, but the upright flowers are borne in *
panicle, instead of l.eiii- «lnioni,,_' ;,n 1 s >lir-iry or in a few-flowerei raceme. EUROPE, NORTH AFRICA, NORTH
ASIA, NORTH AMERICA.
347
348
HUTCHIXSON'S POPULAR BOTANY
FIG. 427. — COLUMBINE (Aquilegia
vulgaris),
With each of the five petals ending in a spur.
honey. This nectary is presented
to the humble-bee just like a spoon
as it sits on the lower lip. Directly
the bee goes, the lower lip snaps
to, and the nectary disappears from
view." The Calceolarias, indeed,
bring before us a new form of
corolla, the calceolate, or slipper-
shaped. They offer good illustra-
tions of special thickenings in
parts of flowers where the strain
caused by insects is most felt.
Calceolaria pavonii is a striking
example of this. Along each of
the upper edges of the curved
basal part of this flower — that part
which carries the inflated end upon
which the bee stands — there is a thickened ridge, and this gives wonderful
strength to the support and prevents injury when the bee alights.
The very cohesion of the petals, in this as in all flowers where cohesion
takes place, is also a source of
strength : and swellings and hollow
projections in particular places may
subserve a similar end. The bulge
in the tubular part of the Foxglove
flower is evidently for this purpose :
as in all probability are the curious
projections in many kinds of gibbous
or pouched corollas. The Great
Wild Valerian ( Valeriana ojficinalis.
fig. 418) offers a good example of
this form. The small pouch or
hump in this particular flower is
the nectary, in the green fleshy
floor of which the honey is secreted.
As the pouch is short and easily
accessible, the flower is largely
patronized by insects, and cross-
pollination regularly takes place.
Returning for a moment to the
simpler kinds of gamopetalous
flowers, notice a familiar example
FIG. 428.— PAPILIONACEOUS COROLLA, of faQ globose corolla (fig. 430). It is
With the parts separated, (r) Yexillum or standard j.1 T\'' d LI' 1
(a) Ate or wings, (c) carina or keei. the Figwort (Scrophiilaria noctoso),
FLORAL FORMS AND THEIR RELATIONS TO INSECTS 349
which blooms in moist places from July to September. Perhaps it is
not the best instance that might be given of the globular form some
of the Heaths (Erica) would better fulfil the requirements of the name
— but we have adopted it because the flower is one of those which,
unlike the flowers which we have been hitherto considering, lay them-
selves out for pollination by insects with short probosces. Wasps are
its chief visitors, and easily reach down to the honey at the base of
the corolla : while long-tongued insects, such as humble-bees and butterflies,
avoid the flower altogether.
The globular form
often merges impercep-
tibly into the urceolate,
or urn-shaped — indeed,
a single spray of Heath
will sometimes show
both forms (fig. 431) —
but a better example
of an urceolate flower
than the Heath is the
Whortleberry ( Vacci-
nium myrtiLlus), the
corolla of which might
have furnished designs
to the sepulchral-urn-
makers of ancient
Etruria (fig. 422). As
a rule, only insects with
a proboscis long enough
to reach from the ex-
terior to the base of the
corolla, where the honey
is lodged, can reach
that coveted treasure,
as the opening is too
narrow to admit the
bodies or even the heads
of the majority of
nectar-sipping insects.
A curious and exceptional form of corolla is the mitrseform or mitre-
shaped (fig. 423). It occurs in the Grape Vine (Vitis vinifera). The five
petals, which are coherent at their tips, form a dome-like covering to the
stamens and ovary ; but they are green and insignificant, and hardly dis-
tinguishable from the foliage ; on which account they are valueless as insect
lures. The plant, therefore, does well in getting rid of them as soon as possible,
Photo by}
[E. Step.
FIG. 429. — YELLOW TOADFLAX (Linaria vulgaris),
With personate or mask-like corolla. The upper and lower lips close
tightly to keep out all insects but bees.
350
HUTCHINSON'S POPULAR BOTANY
FIG. 430. — FIGWORT,
With sub-globose corolla. Adapted
for pollination by wasps.
and this is effected in a beautiful manner. The
petals become detached at their base, and curl up
spirally — that is to say, towards their common point
of attachment at the apex of the flower ; and in
this condition they remain till, by the expanding
of the stamens, they are thrown off completely.
A more interesting, because more intricate,
form of irregular flower than any which we have
yet considered is that which constitutes the
characteristic feature of the well-known and
extensive sub-order of Legumiiiosse, to which
the Pea and Bean belong — namely, Papilionacese. This name at once
suggests the form of the corolla, which Tournefort and Ray, and the early
botanists generally, conceived to bear a resemblance to a butterfly with
expanded wings. Papilio is the Latin word for '• butterfly," and hence the
corolla came to be called papilionaceous and the sub-order Papilionaceae.
But it was reserved for a modern philosopher to advance the startling
suggestion that possibly the first butterflies were flowers "which got loose
from their stalks and flew away " ! Papilionaceous flowers are pollinated
almost exclusively by bees, to which the several parts of the corolla bear
the most evident relation. The reproductive organs (stamens and pistil) are
contained in the two inferior petals (fig. 428), which cohere to form the keel
or car-ilia (cc), the latter an excellent contrivance for protecting the anthers
from pollen-feeding insects and from rain. The lateral petals (a a) — known
as the wings or aloe, — besides affording a platform for bees, serve as a lever
to depress the keel, as well as to bring it back to its place after depression,
if repeated insect-visits are necessary for pollination. Lastly, the large
posterior petal, which is known as the standard
or vexillum (v), gives conspicuousness to the
flower, as well as closes the entrance to the
nectary from behind, so that insects seeking honey
must sit either on the keel or wings.
We must not conclude these remarks upon
the forms of calyxes and corollas without some
reference to composite Row GIB A composite flower
is really a number of florets crowded together on
a single base or receptacle, such as we find, for
instance, in the flower-head (capitulum) of a Daisy
(BMis perennis) or Dandelion (Taraxacumofficinale).
We have chosen for illustration the flower-head
of a Chrysanthemum (C. carinatuTri), the florets
of which are more easily distinguished than are
those of the commoner flowers above named.
What you see (fig. 433) is a section, the flower-
FIG. 431.— HISPID HEATH.
Complete flower (upper), and the same
after removal of calyx and corolla, to
show position of stamen* and pistil.
351
352
HUTCHINSON'S POPULAR BOTANY
FIG. 433. — ANNUAL CHRYSANTHEMUM (Chrysanthemum carinatum).
Section througn a flower-head (capitulum) to show how tlie numerous florets are arranged upon the receptacle.
head having been cut through longitudinally in order to exhibit a perfect
row of the disc florets. Each of these florets, which you will observe are
tubular in form, is a perfect flower, capable of setting seed. The corolla-
tube covers at its base the ovary, and hides from view the greater part
of the styles, the only portion visible being the end which bears the
branched stigmas. Surrounding the flower-head are some florets of another
kind, each of the so-called petals being a female flower, or, in scientific
parlance, a rayed floret with ligulate (i.e. strap-shaped) corolla.
One of the great purposes effected by the massing together of the florets
in composite flowers is admirably suggested by Kerner in his remarks upon
the taking up of pollen by insects. " Great quantities of pollen," he tells us,
" adhere to the under parts of insects in the case of composite inflorescences.
Shortly after the opening of the corollas the style bearing an external load
of pollen is exserted from each of the little tubular and ligulate florets
composing the capitulum in this group, and, owing to the fact that large
numbers of these florets invariably open simultaneously, numbers of styles
laden with pollen project close together from the discoid head. A largish insect
settling on a capitulum may therefore be dusted with the pollen of numerous
florets at once." Darwin observes that the ray-florets of composite flowers
protect the florets of the disc by folding inwards at night and during rainy
? r F
CLOSE-HEADED BEKARIA (Befario
ctata).
The Befarias are a semis of plants
districts of Peru. The apparently
undersides. The purple flowers for
elated to the Rhododendrons. The species illustrated is a native of the Alpine
owiU-il. but really alternate leaves are oblong-, smooth and leathery, with grey
a terminal corymb, and their footstalks and sepals are covered with rusty cotton.
FLORAL FORMS AND THEIR RELATIONS TO INSECTS 353
weather. Composite flowers constitute the largest order in the Vegetable
Kingdom (Composite), about one-tenth of the Flowering Plants belonging to
it. A characteristic of this order not yet touched upon, yet intimately con-
nected with our present subject, is the production of a pappus from the limb
of the calyx. Two forms of such hairy crowns are the sessile and the
stipitate. The formation of a pappus is looked upon as a modification of the
calyx. It is made subservient, as every child knows, to the scattering of
the fruit.
In not a few flowers the corolla is provided with a supplementary organ
known as the corona or crown, sometimes called the paracorolla, which in some
cases is small and inconspicuous, and in others large enough to add materially
to the beauty or singularity of the plant. A corona is one of the dis-
tinguishing marks of the large genus Narcissus , to which our own Wild
Daffodil (Narcissus
pseudo-narcissus)
belongs. In a less
exaggerated form
this " corona " will
be found also in the
Forget - me -not
(Myosotis) and
Primula. Henslow
(Journal of the
Linnean Society,
vol. xvi., 1877) re-
gards it as a de-
velopment of a fold
in the inner epider-
mis of the corolla.
In the well-known
Poet's Narcissus (JV.
poeticus) the white
crown is surrounded
by a cinnabar-red
border, which is
probably a means
of attracting in-
sects ; and in most
species of the
family this organ
is either delicately
marke d or the
whole of the
corona is of a
ii— 5
Photo by] \.E- SleP-
FIG. 434. — HENBANE (Hyoscyamus niger).
The yellow corolla is veined with purple, and the urn-shaped calyx is persistent. The
seed-vessel is a box or pyxis with a well-defined lid.
354 HUTCHINSON'S POPULAR BOTANY
deeper colour than the rest of the perianth. The crown of the Passion-
flower (Passiftora), which in some species is single, in others double, is
split up into narrow threads which Fritz Miiller, a naturalist who has
given much attention to the mechanism of floral organs, believes to be
of service in detaining small insects in the lowest chamber of the flower,
and keeping them caged for humming-birds, the chief pollinators of many
species of Passiflora.
In the White Dead-nettle (Lamium album} there is a circle of hairs in the
narrow part of the corolla-tube, near the base, which serves the purpose of
excluding flies and small bees from the nectar, these being useless to the
plant. The corona of our beautiful bog-flower, Grass of Parnassus
(Parnassia palustris), is very interesting. It consists of five scales (the
nectaries) terminating in hairs, each of which is surmounted by a yellow
FIG. 435. — ANTHERS AND THEIR DEHISCENCE.
(a) Longitudinal, (6) transverse, (c) valvular, (d) porous dehiscence ; (e) cross-section of stamen of a Lily
(/) stamens of a Milkwort (Polygala erioptera).
glandular body, which has all the appearance of a drop of fluid. Even flies
are deceived by these shining knobs, mistaking them for drops of honey.
We come now to the stamens or male organs, which are known col-
lectively as the andrwcium. The forms of these, like the forms of the calyx
and corolla, vary considerably. Bearing in mind what has been said
already about the stamens in connection with cohesion and adhesion,
there is really little else to be acquired.
It is instructive, however, to notice the diversities of form and
mechanism which the andrcecium presents, and which are usually connected
with that most important function, the scattering of the fertilizing meal
or pollen. Thus, in the Grasses (Graminese) and Plantains (Plantago) whose
pollen is carried by the wind, the anthers swing loosely on their connectives,
and so assist the wind in its useful labour — they are versatile ; while in cer-
tain species of Sage (Salvia) the connective forms a curved bar or lever, and
FIG. 436.— PISTILS.
(a) Canterbury Bell ; (6) Pansy : transverse section of young ovary ; (c) Pansy ; (d) Begonia ; («) White Campion
(/) Calceolaria ; (?) Clarkia ; (*) Periwuikle.
355
356 HUTCHINSON'S POPULAR BOTANY
runs transversely to the filament, to which it is attached by a movable
joint, the purpose of which will be explained hereafter. From some stamens
the filament is entirely absent, and the anthers, which are then described as
sessile, may be attached either to the petal of the flower, as in Vervain
(Verbena), or to some part of the pistil, as in the Birthwort (Aristolochia).
In a large number of cases the connective is perfectly continuous with —
or, in other words, is a direct prolongation of — the filament, the point of
attachment of the anthers being immediately upon the top of the filament ;
but far more frequently the latter is prolonged up behind the anther-lobes.
The terms basifixed or innate and dwsifixed or adnate are applied respectively
to these two kinds of attachment.
When the face of the anther — or, in other words, the surface opposed to
that to which the connective is attached — is turned towards the pistil of the
flower, the stamens are said to be introrse : when, on the other hand, the
face is turned towards the petals, the stamens are extrorse. The direction in
which the anthers dehisce — that is, discharge their pollen — is thus largely-
dependent upon the position of the stamens — a fact to be carefully noted.
The mode of de-
hiscence is chiefly
determined by the
nature of the aper-
tures through which
the pollen escapes.
When, as is most
frequently the case,
FIG. 437.-STAMENS OF (a) LITS^A ; (6) PYKOLA ; (c) GARCIXIA. the anther opens by
narrow upright slits
running from top to bottom of the lobes, the dehiscence is said to be
longitudinal ; when the lobes are slit crosswise, the dehiscence is transverse.
In not a few flowers the lobal orifices are wide and concealed by delicate
valves or flaps, which lift up like a trap-door at the moment of shedding
the pollen. This is valvular dehiscence. When, as in the case of the
Common Whortleberry (Vaccinium myrtillus), the dehiscence is effected
by minute fissures or pores at the tips of the lobes, we speak of it as
porous.
The anthers assume the most various shapes — globular and oval,
pear-shaped and worm-shaped, curved and undulating (the latter a form
which reminds one of the convolutions of the human brain), pitcher-like
and box-shaped, etc., etc. ; while many of these forms are rendered still
more striking by the presence of appendages in the shape of hairs, tubes,
fleshy hooks, leaf-like expansions, coloured bladders for attracting insects,
feathery growths, and other singular contrivances whose name is Legion.
Such appendages are usually prolongations of the connective. The almost
naked stamens of Leitneria floridana, a shrub with willow-like leaves
FLORAL FORMS AND THEIR RELATIONS TO INSECTS 35?
inhabiting the marshes of the southern United States, are seated upon
bracts, furnished with hairy appendages, which give a curious flocculent
appearance to the whole inflorescence. The morphology of the gyncecium,
or pistil, need not detain us long. A pistil also consists of three parts — the
ovary, the style, and the stigma. Just as the stamen assumes different
forms according as its filament is long or short, its connective with or without
appendage, its anther-lobes globular or oval, pear-shaped or linear, etc., etc.,
so the form of the pistil varies in accordance with analogous diversities in
the ovary, style, and stigma. The mode of insertion of the style is also a
cause of variation. It may spring either from the top of the ovary, when
it is terminal ; or from the side, when it is lateral ; or from the base, when
it is basilar. Sometimes it is entirely absent, and then the stigma rests
upon the ovary, and is said to be
The style, indeed, is not an
essential part of the pistil ; the
stigma is. It will be remembered
that the latter is the organ which
serves for the detention of the
pollen-grains. Nature, as might
be guessed, has all sorts of devices
for facilitating this object, and
hence the multitudinous forms of
stigma— peltate, plumose, penicillate,
petaloid, etc. — which the pistils of
flowers present.
It should be added that the
relative position of the calyx,
Corolla, and Stamens to the pistil Section through perigynous flowc
is a matter of considerable importance. Observe the flower of a Geranium.
Here the ovary is superior to the other floral organs, which are attached
to or below its base. Such a flower is termed hypogynous, from the Greek
words hupo, under, and gune, a woman. Compare these with the sections
of the flowers of Rose and Apple, in which, by the more vigorous growth
of the axes, a tube is formed around the carpels, and the stamens and
perianth are raised so that they stand on the apex of the rim of the tube.
The Rose and Apple are perigynous flowers (Greek peri, around, and gune).*
In the Begonia and Carrot we have a third mode of insertion. In both
cases the ovaries are situated below the perianth— they are inferior;
whilst the flowers as a whole are described as epigynous (Greek epi, upon,
and gune).
* In the case of the Rose, each of the carpels has a distinct ovary ; in the Apple the ovary
fills the \vhole cavity of the tube, with the inner wall of which it is fused. The immature
" pips " are ovules, not ovaries.
Photo by]
FIG. 439. — SWEET VIOLET (Viola odorata).
Showing the reversal of the flower by the curving of the flower-stalk. The plant to the left is the white-flowered form.
CHAPTER XII
THE WELCOME OF THE FLOWERS
These have their sexes! and when summer sliines.
The bee transports the fertilizing meal
From flower to flower, and e'en the breathing air
Wafts the rich rrize to its appointed use.
COWPEB.
THE important part which insects and other external agents play in
the fertilization of flowers was indirectly alluded to in the last
chapter, and we propose now to follow out this interesting subject in
some detail.
The insects which visit flowers may, for popular purposes, be divided
into two classes — bidden and unbidden guests : the former being useful to
the plant, the latter useless. It may be added that an insect which is a
welcome visitor to one kind of flower may be an unwelcome visitor to
another; so that the terms " bidden" and " unbidden'7 have only a relative
significance. Incidental allusion has been already made to some of the
contrivances in plants for the exclusion of certain visitors : we may now
consider a few more of these contrivances, with special reference to the
flower.
Of the necessity of excluding various kinds of insects from certain
flowers there can be no question. ;' Guests might come,'' says Dr. Ogle,
358
[Henry Irving.
FIG. 440. — SNOWDROP (Galanthus nivalis).
The Snowdrop produces but a single flower throughout the year, but thuMower, if unfertilized, •£«»*£ fresh and
open for a lona period ; and hence, if deprived of the visits of hive-bees (its chief pollinatore) for many days .at a time
which may often happen in consequence of unfavourable climatic conditions), the ability to hold out is of greal
advantage to the plant. EUROPE and w. ASIA.
359
360
HUTCHINSON'S POPULAR BOTANY
FIG. 441. — CYCLAMEN
(Cyclamen europceum).
in his amusing preface to Kerner's famous little
book, Flowers and their Unbidden Guests, " who
were not of sufficient importance, and the ban-
quet [whether of nectar or pollen] be wasted
on them ; for it is only when insects have a
certain shape, size, or weight that she requires
their visits, and can use them profitably for her
purposes. . . . All insignificant and unremunera-
tive visitors, all such, moreover, as would creep in
by the back entrance, must be kept out."
Thus the opposite leaves of a plant may form
a kind of collar, or series of collars, to the inflor-
escence, insurmountable to wingless insects from
below, as is the case in many Gentians ; or even
the stipules and alternate leaves may act in the same way, as in the
Common Pear and Thorow-wax respectively.
How excellently, again, is a pendulous flower adapted for the exclusion
of small creeping insects ! Take the Snowdrop (Galanthus nivalis, fig. 440).
Where is the ant that could get inside the hanging flowers of this February
maid ? — if the ant were in the habit of climbing up plants at that season.
The slippery curved walls would defy all its efforts ; and, as a matter
of fact, only winged insects pollinate the flower. Hive-bees, which are the
most useful to the plant, enter the drooping bells without difficulty.
When the object of a hive-bee's search is the
pollen, " it thrusts its head, fore-legs, and mid-
legs into the flower, clinging by means of its
hind-legs to the outer surface of an inner perianth-
segment. With the tarsal brushes of its fore-
and mid-legs it sweeps pollen from the anthers
and places it in the baskets on its hind-legs. If
it wishes to suck honey, it usually finds it more
convenient to use its own fore- and mid-legs for
clinging to the perianth." * In either case the
bee's head gets well covered with pollen, some of
which is sure to be deposited on the stigma of
the next flower which it visits, for the style of
the Snowdrop projects beyond the anthers, and
.the bee's head must come in contact with the
stigmatic surface on entering.
The curvature of many perianth leaves also
subserves the purpose of excluding wingless
insects from the nectar and pollen. "I placed,"
FIG. 442.— PLUMBAGO sa^s Kerner, " some small and by no means timid
(Plumbago capensis). * Miiller : Fertilization of Flowers.
THE WELCOME OF THE FLOWERS
361
ants, of a kind (Lasius nigra) which under ordinary circumstances show
themselves to be capital climbers, on the flowers of Cyclamen europceum
(fig. 441). At first they tried to make their escape downwards by the
peduncle ; but as I had put the flower-stalk in water, they turned back and
managed to recross the calyx and get back to the corolla. After some
useless clambering about the reflexed tips of the petals, they at last reached
their curved margins,
and here all their skill
was baffled, and they fell
either into the water or
to the ground."
The calyx, epi-calyx,
and bracts may be
further protections to
the flower, by prevent-
ing insects from eating
their way through the
corolla to the nectary,
a burglarious proceeding
of which even bees are
sometimes guilty. We
have seen how admir-
ably an inflated calyx
effects the same results,
holding the would-be
intruder at a distance
from the honey, even
when the tissue has been
gnawed through ; and
the fact might be en-
forced by other exam-
ples. Hermann Miiller
remarks of one of the
Louseworts (Pedicularis Pfotow ^.
FIG. 443. — MARSH CALLA (Calla palustris).
The white spathe serves as an alighting platform for the flies that are attracted
by the unpleasant odour to pollinate the flowers.
verticillata) that "the
calyx is swollen, and
the lower part of the
corolla-tube is bent at right angles within the calyx; the honey is^thus
guarded from Bombus mastrucatus, which tries in vain to reach it." In
the Canterbury Bell (Campanula medium) the tough inflated hairy calyx,
with its valvate divisions, stands above the ovary, the nectar being
sufficiently guarded by the expanded bases of the five stamens which
surround it (fig. 436 a); while in Clarkia (fig. 436 g) the curious boat-
shaped gamosepalous calyx, like the curved petals of the Cyclamen referred
362
HUTCHINSON'S POPULAR BOTANY
to by Kerner, is an admirable contrivance for keeping out small wingless
insects.
We have seen how perfectly the flowers of Antirrhinum and Toadflax
are adapted for the exclusion of certain intruders, and many equally perfect
adaptations of
corolla and calyx
might be enumer-
ated, where the same
end is to be gained.
In a number of in-
stances, the corolla
" forms a narrow
tube, still further
protected by the
presence of hairs,
sometimes scattered,
sometimes, as in the
White Dead-nettle,
forming a row. In
others the tube itself
is so narrow that
even an ant could
not force its way
down : while in some
of the Gentians the
opening of the tube
is protected by the
swollen head of the
pistil. ... In Clover
1 Trifolium), Birds-
foot Trefoil (Lotus),
and many other
LeguminossB, the
ovary and the
stamens, which cling
round the ovary in
a closely fitting tube,
fill up almost the
whole space between
the petals, leaving only a very narrow tube. In still more numerous
species the access of ants and other creeping insects is prevented by the
presence of spines or hairs, which constitute a veritable cheval de frise.
Often these hairs are placed on the flowers themselves, as in some Verbenas
and Gentians. Occasionally the whole plant is more or less hairy : and it
Photo fry] [B. Step.
FIG. 444. — MARSH MARIGOLD (Caltha palustris).
A splendid Buttercup whose brilliance is due to the golden sepals, t!ie
petals being absent.
Photo by} [E. Step.
FIG. 445. — PURPLE LOOSESTRIFE (Lythrum salicaria).
The flowers, though outwardly all alike, are of three forms, differing in the length of the pistils and the filament of
tfie stamens : a plan that secures cross-pollination. NORTHERN TEMPERATE REGIONS and AUSTRALIA.
364
HUTCHINSON'S POPULAR BOTANY
will be observed that the hairs of plants have a great tendency to point
downwards, which, of course, constitutes them a more efficacious barrier "
(Lord Avebury).
Lastly, in not a few cases creeping insects are kept away from the
interior of the flower by viscid secretions on the stem or calyx, to which
the unfortunate visitors get glued, and from which there is usually no
escape. Thus the calyx of Plumbago (fig. 442) is furnished with glandular
hairs, which stand out horizontally from the epidermis, and are fatal to
many a wandering aphis and small fly. The Honeysuckle (Lonicera) is
another familiar instance of a flower which produces these viscid protective
hairs on its calyx, but in the Catchflies (Silene nutans and S. noctiflora) they
are much more effective, as may be judged by the number of small insects
usually found glued to the calyx and flower-stalk.
The Tutsan-leaved Dogsbane (Apocynum androsemifolium) is a plant
which re-
sorts to ex-
treme mea-
sures in
dealing with
un invited
guests. The
French call
it G o b e -
mouche, or
Fly-gulper,
and the
name is well
bestowed.
In tact, the
P.
stamens ot
FIG. 446. — GOATSBEAKD (Tragopogon pratensis).
The involucral bracts are longer than the ray-florets. The flower is supposed to close at noo
(" John-ffo-to-betl-at-noon "). but it is seldom open so late.
the flower have an ugly trick of nipping intruding flies by their probosces
and detaining them as captives till death puts an end to their miseries.
Then the filaments open and the dead insects are released. " Allured by
the honey on the nectary of the expanded blossom," says Knapp, in his
Journal of a Naturalist, " the instant the trunk [of the fly] is protruded to
feed on it, the filaments close, and, catching the fly by the extremity of
its proboscis, detain the poor victim writhing in protracted struggles till
released by death, a death apparently occasioned by exhaustion alone : the
filaments then relax, and the body falls to the ground. The plant will at
times be dusky from the numbers of imprisoned wretches."
More than one plant is known in which the expulsion of unremunerative
visitors is effected, not by the plant itself, but by other and remunerative
insects. Kerner has enumerated four of such plants — Centaurea alpina,
G. ruthenica, Juritiea mollis, and Serratula lycopifolia, all of them belonging
THE WELCOME OF THE FLOWERS
365
to the great Composite order. " The young capitula of these Composites,"
says the eminent naturalist, " are particularly liable to the attacks of
devouring beetles, especially of Oxythyrea fanesta, which bites big holes
in the heads, destroying crowded flower-buds and involucral scales without
the least difficulty.
To meet this danger
a garrison of war-
like 'ants is em-
ployed. Honey is
secreted from big
stomata on the im-
bricating scales of
the st ijl 1-clo se d
capitula in such
quantities that one
can see a drop of it
on every scale in the
early morning, while
later in the day, as
the water evapor-
ates, little masses or
even crystals of
sugar are to be
found. This sugar,
either in its liquid
or solid form, is very
palatable to the ants,
which habitually re-
sort to these capitu-
la during the period
of its secretion, and
to preserve it for
themselves they re-
sent any invasion
from outside. If one
of the afore-men-
tioned beetles ap-
pears, they assume
a menacing attitude.
They hold on to the involucral scales with their last pair of legs and
present their forelegs, abdomen, and powerful jaws to the enemy. Thus
they remain till the beetle withdraws, if necessary hastening its retreat
by squirting formic acid in its direction."
It has been remarked that wingless insects are most active when the dew
,
FIG. 447. — MAKSH LOUSEWORT (Pedicularis paluatris).
Parasitic upon the roots of other plants. It has a dull pink corolla and
reddish-green calyx.
366
HUTCHINSON'S POPULAR BOTANY
FIG. 448. — FLOWER OF
HORSE CHESTNUT.
Hermaphrodite or complete flower
with stamens and pistil.
has evaporated, and that this is the signal for the
closing of many flowers ; but it may be doubted
whether these circumstances stand in the relation
of cause and effect. Flowers open and close at
almost all times of the day and night ; and though
in some cases the periods of their opening have
distinct reference to the visits of bidden guests,
it seems extremely doubtful that the periods of
their closing have any reference to unbidden ones.
Be that as it may, the phenomena of the open-
ing and closing of flowers are full of interest,
and as the subject has been named, we will offer
a few remarks upon it before passing on.
It is well known that Linnaeus devised a floral dock at Upsala, by
grouping together plants according to the hours at which they open and
close, and that for a time the growing of these flower-clocks in public
and private gardens became quite a rage. In recent years Kerner has
repeated the experiment at Innsbruck (47° N. lat.), and a comparison of
his tables with those of the older naturalist has shown that flowers both
open and close earlier in the day at Upsala than at the more southerly
situated Innsbruck. " The result," he says, " especially the earlier opening,
is probably connected with the fact that the sun during the flowering
season of the plants in question rises about an hour and a half earlier
at Upsala than at Innsbruck."
Of the flowers in Linnaeus' clock the earliest to open was the Goatsbeard
(Tragopogon pratensis^ fig. 446), a Composite flower like a large Dandelion,
which has received in this country the name of John-go-to-bed-at-noon,
from its habit of closing about midday.
Broad o'er its imbricated cup
The Goatsbeard spreads its saffron rays,
But shuts its cautious florets up,
Retiring from the noontide blaze.
Owing to its very early opening it has been
pollinated usually long before noon ; and as soon
as a flower has been pollinated it either begins
to close, changes colour, or casts off its now useless
non-essential organs. The latest flower to open
was the magnificent Queen of the Night, which
unfolded its scentless white petals two hours
before midnight.
We approach now a new and more important
division of the subject — namely, the means by
which the pollen of flowers is conveyed to the
FIG. 449. — SECTION OF HORSE
CHESTNUT, MALE FLOWER.
(ov) Rudimentary ovary. There is
no style or stigma.
367
368
HUTCHINSON'S POPULAR BOTANY
stigma as a preliminary to fertilization. The consideration of these means
brings us in touch with those denizens of the insect world which
may be reckoned among the bidden guests of flowers. The subject has
received an extraordinary amount of attention during recent years, and
is practically inex-
haustible. The
phenomena of which
it treats are them-
selves often spoken
of as fertilization,
but this use of the
term — albeit we con-
fess to being fre-
quent offenders in
this respect—is
hardly correct. Pol-
lination is a better
word.
Let us begin with
flowers which pol-
linate themselves.
Now it will be evi-
dent at a glance
that such flowers
must bear the male
and female organs
on the same indi-
vidual ; hence we
call them bisexual or
hermaphrodite.
The presence or
absence of one or
both of the essential
organs of a flower is
a matter of great
importance. One of
^.steP. the commonest
FIG. 451.-ASH (Fraxinus excelsior). hermaphrodite
The flowers are without petals or sepals, and yet are perfect because each one
consists of two stamens and a pistil. flowers IS the
Buttercup (Ranun-
culus). Here the male and female organs are both present in the shining
3^ellow cup, and hence it is not only bisexual, but perfect. Even though
the Buttercup had no calyx or corolla, it would still be perfect. As a
matter of fact it possesses both those organs ; and since, in addition, it
THE WELCOME OF THE FLOWERS
369
possesses both pistil and androecium, it is said to be complete. The absence
of any of the four organs— calyx, corolla, androecium, or pistil — renders a
flower incomplete ; but only the absence of one of its essential organs (i.e.
the andrcecium or the pistil) j renders it imperfect. We are speaking, of
course, not of that
which is accidental
and abnormal, but
of that which is
characteristic of the
flower. Thus the
Common A.sh(Fraxi-
nus excelsior), which
bears its male arid
female organs on the
same flower (fig. 451),
but has no floral
envelopes whatever,
is a perfect flower ;
while, on the other
hand, the Arrow-
head (Sagittaria), in
the different species
of which both calyx
and corolla are al-
ways present, but
which bears the
sexes on different
flowers, is imperfect.
We need hardly add
that, in both cases,
the flowers are in-
complete. It is, then,
evident that all im-
perfect flowers are
either male or fe-
male ; if the former,
,, ,, , Photo by] \E. Step.
they are called 8ta- FIG. 452. — SALLOW (Salix caprea).
minate ; if the latter, The spray
pistillate — na m e s
which explain themselves ; while flowers which have neither male nor female
organs are described as neuter. Of this latter kind are the outer florets of
some of the Composites.
Now, though the sexes are often separated in the manner described,
staminate and pistillate flowers are not always or necessarily borne on
ii— 6
the left consists of the male catkins, the so-called "palm"; that on
the right is made up of female catkins.
370
HUTCHINSON'S POPULAR BOTANY
FIG. 453. — HENBIT (Lamium
amplexicaule).
(a) Perfect flower ; (6) cleistogamic flower ;
(f) section of (&).
different plants. We might, indeed,
liken the androecium and pistil to tenants
in a house where the rooms are flowers
and the house itself is the plant. When,
as in the Oak (Quercus robur), Walnut
(Juglans regifi), and Sweet Chestnut
(Castanea saliva, fig. 450), the male and
female flowers occupy the same house,
they are saicl to be monoecious (Greek
monos, one, and oikos, house); when, as in
the Juniper (Juniper us), Poplar (Populus),
and Willow (Salix. fig. 452), the sexes not
only occupy different rooms, but different
houses, being borne on distinct plants, the
flowers aie appropriately termed dioecious
(Greek di, two. and oikos}. Hence, too,
the plants themselves are capable of
sexual classification, some being male, others female, others bisexual, and
a fourth class, in which male, female, and hermaphrodite flowers are
found on one and the same individual, polygamous.
With this digression, let us revert to the subject which led to it — the
pollinating of a flower by its own anthers. The process of self-pollination
is the first stage of autogamy, which, as already explained, is the fecundation
of a flower by its own pollen ; and the whole process may, and sometimes
does, take place without the flower opening at all. It has, indeed, been
discovered by comparison of several closely allied flowers that the smaller
ones are frequently self-pollinated — nay, that in some cases the same plants
which produce ordinary cross-pollinated flowers produce minute self-
pollinated ones which never open. Thus we may say that there are two
kinds of autogamous flowers — those which open like ordinary flowers, and
those which remain closed. A glance at an example or two will make the
fact additionally clear.
To take the last-named first. These, as the whole process is effected in
the closed flowers, are called cleistogamic, a name derived from the Greek
kleislos, closed, and gamos,
marriage. The Henbit
Dead-nettle (Lamium am-
plexicaule) offers excellent
examples of cleistogamic
d ^^^ flowers. The richly tinted
reddish-purple corollas of
FIG. 454. — FLOWERS OF Myosotis IN SECTION.
(a) Wood Scorpion-grass; (6, c) Yellow and Blue Scorpion-gra;
(d) Forget-me-not.
the. expanded blossoms of
this not uncommon weed
are familiar to most persons
Photo fty]
** | ,7 £ |[ FIG. 455. — HARD HEADS (Centaurea scabiosa).
utiful composite flower, with all the florets rayed, and of a bright purple colour. The overlapping bracts ol
the involucre have toothed brown margins. EVROPE, SIBERIA, W. ASIA.
371
372
HUTCHINSOX'S POPULAR BOTANY
(fig. 453, «). They are met with in dry and sandy fields during the sultry
months of July and August : but few probably have noticed, earlier in
the year, the small bud-like unexpanded flowers of this plant ifig. 453, 6).
These are cleistogamic flowers, which never open — undeveloped flower-
buds, with anthers and stigmas that mature so that perfect fruits are pro-
duced. "Were you to open one of these buds at the moment of pollination
(fig. 453, c). you would find
that the long and flexible
style (st) had curled round
so as to bring the inner side
of its forked stigma in con-
tact with one of the anthers.
Perhaps you would even
find that the anthers had not
opened, but that the pollen-
tubes had perforated its
delicate walls and were
growing in the direction of
the stigma.
The Dog-violet (Viola
canina) is another plant
which produces these un-
developed flowers. Pro-
fessor Ainsworth Davis re-
marks that " in summer the
ripe fruit of the cross-
pollinated flowers will be
found, and, close to them,
minute bud-like structures.
These are the cleistogamic
flowers : their anthers are so
placed that the pollen-grains
can send their tubes straight
to the stigma. Such a
flower produces, perhaps,
only two hundred pollen-
grains, as opposed to some
thousands in an ordinary blossom." As a rule, indeed, cleistogamic flowers
are pollen saving. Thus, a single self-pollinating flower of Wood-sorrel
(Oxalis acetosella) contains about four hundred grains : a flower of Touch-
me-not Balsam (I'mpatieiis noli-me-tangei'e) about two hundred and fifty :
and of Cut-grass (Leersia) not above fifty. Contrast these figures with
the number of pollen-grains in the Peony, 3,500,000, or in a single flower-
head of Dandelion. 365.000 !
FIG. 456. — GREAT WILLOW-HERB (Epilobium hirsutum).
(a) Flowering branch ; (6, c) stamens and pistil arranged for cross-
pollination. In () held by tentacle (a).
drawing also shows one of
the two lateral petals, with
its tuft of hairs. Both of the
lateral petals are furnished
with these hairs, which aid
the bee in clinging to the
flower. In some species of
Viola the grooved part of the
inferior spurred petal is also
fringed with hairs, but they
are for collecting pollen.
Photo by} [H. In-in
FIG. 513. — YUCCA-PLANT (Yucca gloriosa).
This plant is cross-fertilized by insect agency in a manner which makes it one of the wonders of the vegetable world.
Tho process is fully described in a later chapter.
411
412
HUTCHINSON'S POPULAR BOTANY
Now, when a bee wants to reach the honey in a flower — say, of Viola
tricolor — it must insert its proboscis close under the capitate stigma, and
this, as shown in the sketch, lies in the groove of the inferior petal. Into
this groove the anthers shed their pollen, either of themselves or when
the pistil is shaken by the bee, and hence the insect's proboscis, in passing
down the groove to the spurred nectary, gets plentifully dusted with the
yellow meal. As the proboscis is withdrawn, it shuts to the flap-like door
of the stigmatic chamber, so that, for the nonce, no pollen can enter that
cavity ; but when the bee thrusts its head into the next flower, it leaves
some of the precious dust on the upper surface of the flap.
In the Alpine Liane (Atragene atpina) the grooved inner surface of the
basal half of the stamens forms the nectary. " The pendulous violet
flowers," says Hermann Miiller, "only give up their honey to insects
which can force asunder the numerous stamens, which are set closely
in several
whorls," and
which, we
may add, are
held together
on the out-
si de by a
whorl of stiff,
erect, spoon-
shaped stami-
nodes.* Bees
and h u ru-
ble-bees are
* A stami-
node is a barren
stamen, more or
less filiform in
shape, placed
either within or
without the per-
fect stamens, but
not furnished,
like them, with
anthers at the
apex. H. Miiller
calls the stami-
nodes of Atra-
gene alp in a
" petals " ; Ker-
ner, " leaves " ;
Baillon, "stami-
nodes."
FIG. 514. — Odontoglossum alexandrce.
(a) A spray of flowers ; (6) A single flower ; (c) Pseudo-bulbs and leaves.
THE WELCOME OF THE FLOWEES
413
among the few in-
sects powerful
enough for this
work; and, in point
of fact, they alone
have been observed
to pollinate the
plant.
The nectaries of
cruciform flowers
(Cruciferae) are
usually glandular
swellings at the base
of stamens, the
honey when secreted
either remaining in
drops upon the
glands, or accumu-
lating in the spaces
between the stamens
and pistil and in the
sepaline pouches.
The Cuckoo-flower
(Car da/mine praten-
sis, fig. 483) — of
which Gerarde
quaintly says, '• it
doth bloome in April
and Maie, when the
cuckoo doth begin
to sing her pleasant
notes without stam-
mering " — is a good
example. The nectar
glands are the green
fleshy cushions at the bases of the two shorter and the two aborted stamens,
and the honey secreted by these glands accumulates in the pouched bases of
the sepals. " In the young bud all the six anthers are turned towards the
pistil, which projects above 'them. Before the flower opens the four inner
stamens elongate and overtop the stigma, and make a quarter of a revolution
outwards, each one towards the small stamen nearest to it ; so that now
an insect, in trying to reach the honey of one of the larger glands [those
surrounding the bases of the shorter stamens], must rub its head or proboscis
against the pollen-bearing surface of one of the taller anthers " (Miiller).
FIG. 515. — Vallisneria spiralis.
Female plant on the left ; male plant on the right.
414
HUTCHINSON'S POPULAR BOTANY
FIG. 516. — FLOWER or NETTLE
(Urtica dioica).
The male or staminate flower.
In the Pasque-flower (Anemone pulsatilla)
we have an instance of stamens metamorphosed
"lto nectar^es — or rather °f rudimentary sta-
mens, with shortened filaments, and glands
instead of anthers (fig. 486). In Papilionaceous
flowers, like the Pea and Bean, the cohering
fertile stamens secrete and store the nectar
(figs. 497-499). They form a tube around the
ovary, and the honey is poured into the base
of the tube.
Very curious are the nectaries of the
well-known Petty Spurge (Euphorbia peplus),
so common as a garden weed throughout the kingdom (fig. 487). The
border of the cup-like involucre is studded with shining, crescent-
shaped glands, which are much resorted to by flies, beetles, and other
short-lipped insects, on account of the nectar with which the glands are
coated. They are, in fact, the nectaries ; and by their prominence and
accessibility they compensate for the inconspicuousness of the flowers.
There is a nearly allied plant to the Spurges, a species of Dalechampia,
which, according to Fritz Miiller, attraci-ts the insects which cross-pollinate
it by means of a colourless resin secreted in special glands. This resin
is collected by the insects (bees), and used in nest-building. In the Carrot
(Daucus\ Elder (Sambucus), and Ivy (Hedera) the nectary is also conspicuous,
lying almost on the surface of the flo.wer.
Ovarian nectaries are found in Antirrhinum, Speedwell (Veronica}.
the Common Comfrey (Symphytum officinale), and other plants. In the
Spiked Speedwell (V. spicata, fig. 489) the fleshy base of the ovary secretes
the nectar, and the tube of the corolla holds it like a cup. A ring of
long stiff hairs at the mouth of the tube
shelters the nectar from rain. This is also
the case with the Brooklime (V. becccibunga),
which is freely visited by insects, particularly
flies. The ovarian nectary of Comfrey (fig. 505)
is a white annular ridge, and in order to get
at it the insect (usually a humble-bee) has to
force apart the anthers, which form an inverted
cone near the mouth of the tubular corolla.
This releases the pollen, which falls upon the
insect, and in due course is transferred to
another flower.
Other nectaries are sometimes found on
the foliar parts of plants, at a considerable
distance from the flowers. " It is always
pleasant," says a writer in Nature, 1893, " to
FIG. 517. — FLOWERS OF
VALLISNERIA.
(a) Female flower ; (t>) bud of male flower ;
(r) male flower open.
3- «.
lit
L
415
416
HUTCHINSON'S POPULAR BOTANY
hear the contented hum of the bees amongst the young Laurel leaves
[of Cerasus lusitanica} ; for
with no ulterior ends of
their own the prosaic green
bushes regale their friends
with the sweets secreted by
the yellow glands at the
bases of their leaves, and,
whatever may be said to the
contrary, afford a triumphant
proof that plants are not
exclusively selfish and utili-
tarian, as we in our half-
knowledge are sometimes
apt to imagine." Certain
species of Primus (e.g. the
Cherry, P. cerasus) produce
nectaries in the form of
small red glandular swellings
on their leaf-stalks (fig. 489),
though the receptacular
tubes of the flowers also
secrete honey. The Broad
Bean, again (Vicia faba\ has
nectaries on its stipules (fig.
490) ; so have the Vetch
( V. sativa} and the Scabrous
Balsam (Impatiens tricomis).
These secretory glands
appear to be an ingenious
device for enlisting the
services of ants.
It is probable that the
writer in Nature just quoted
would have modified his
statement had he inquired
a little further. The truth
is that the provision of
these nectar-glands on the
foliage of plants, so far from
-are bud-like with crimson threads (stigm^lrotr^iny^Tom^th^top'. being evidence of the plants'
These later develop into the familiar Hazel-nuts.
philanthropy, is like much
that passes for the same virtue in our species — dictated by strict business
considerations. Instead of causing a net drain upon the capital, it yields
-Photo W [£. Stef
FIG. 519. — HAZEL FLOWERS (Corylus avellana).
The long, swinging catkins consist of male flowers only. The female flowers
BLUE VANDA (Vanda ca-rulea).
A representative of a genus of Indian and Malayan Orchids. The pale blue flowers are here represented little more thai
half the natural si/e, which is about five inches across. Ten or twelve of them are produced in a raceme on a stem twi
or three feet high. It is a native of Northern India and Burmah.
THE WELCOME OF THE FLOWERS
417
Photo by]
FIG. 520. — WOOD ANEMONE (Anemone nemorosa).
[E. Step.
A beautiful woodland spring flower. Flowers and leaves arise separately from a woody underground creeping stem.
It has no petals, but the sepals are coloured to take their place. Although providing no nectar, the flowers are visited
by insects who assist in cross-pollination.
a handsome percentage of profit. In some strange way the plants have
learned that much of the food of ants consists of other insects, and that
it is good to be rooted within reasonable distance of a nest of ants ; for
the industrious and usually pugnacious little creatures climb trees and
other plants in search of insects that are fretting the leaves, and if at the
same time they can get a little of the sugar they so greatly desire, they
will make a point of patrolling the plant that supplies it, and for their
own ends keep it clear of insects other than their own domestic Aphides.
We have mentioned several plants that produce these nectar-glands on the
leaf-stalks or stipules ; but it is stated that more than three thousand
species are known to make this provision for their ant friends. Some of the
Acacias not only make it worth the while of this patrol to remain on
duty, but they provide sentry-boxes for their convenience. Instead of
stipules, they produce a pair of large hollow spines in which a number of
ants can be, and are, housed. They take care also to produce nectar,
which is poured out by glands on the leaf-stalks, and some of them in
addition bear queer little bodies, formed of albuminous matter, at the
tips of the leaflets. These bodies are produced as food for the ants,
ii— 9'
418
HUTCHINSON'S POPULAR BOTANY
and their removal does not injure the plant. In other lands cultivators,
who are perhaps more observant than the same class in this country,
have taken advantage of these facts for the protection of their fruit crops.
The orange growers in the province of Canton, instead of depending on
natural arrange-
ments, collect ants'
nests and connect
them with their
trees ; and a similar
practice is adopted
by the fruit-growers
in parts of Italy.
(See Step's Mess-
mates: a Book of
Strange Partner-
ships.}
That the quanti-
ty of nectar secreted
by the flower varies
greatly in different
plants goes without
the saying. While
in some species the
amount is so small
as to be hardly dis-
coverable, in others
the blossoms liter-
ally flow with it.
In the interesting
Honey-flowers (Meli-
anthus), a genus of
strongly scented
South African
shrubs, the secre-
tion is enormous.
In Melianthus major
an actual '; rain of
honey " pours from
the cowl-shaped
petals when the iii-
florescence is
shaken. In the wonderful Coryanthes, a genus of tropical orchids, the
nectareous fluid is secreted near the base of the stalk, and drips con-
tinuously into the helmet-shaped lip at the time of flowering. Upwards
Photo by]
FIG. 521. — FIELD WOOD-RUSH (Luzula campestris).
. Slep
A wind-fertilized plant, with grass-like leaves fringed with soft white hairs. The
flowers in are cymes, mostly on slender, swaying branches.
FIG. 522. — LADY'S TRESSES (Spiranthes autumnalis).
A. native Orchid of dry pastures and hillsides. The small fragrant white flowers are arranged J£ spindrOTW Igjon
the stem. The leaves appear in little rosettes after and apart from the flowering stein. EUROPE, NOi
419
420
HUTCHINSON'S POPULAR BOTANY
of an ounce of the fluid has been found
in one of these receptacles.
So much for Nectaries. We have
now considered five of the means by
which insects are attracted to flowers
with a view to the transference of
pollen, and only one remains to be
spoken of. The five already treated
are Conspicuousness, Odour, Irregu-
larity, Honey-guides, and Nectar :
the sixth is the fecundating dust
itself.
In the majority of insect-pollinated
flowers the pollen-grains are either
rough or sticky, and thus are distin-
guished from the pollen-grains in wind-
pollinated flowers, which are usually
smooth. The reason of this is obvious.
The rough and sticky kinds — " clinging
pollen," as Kerner calls them — are
adapted for clinging to insects visiting
the flowers ; the smooth kind — dusty
pollen — is not less adapted for disper-
sion by the wind ; for being easily
taken up by the slightest breeze, and
having no inequalities of surface, its
resistance in passing through the air is of the slightest.
Few objects are so beautiful under the microscope as the pollen-grains
of flowers. Not only do they vary greatly in their general forms, but
their walls in many instances show the most exquisite sculpturing and
patterns, which — if animals of the lower creation are as susceptible to
beauty of form as man — must delight the eyes of the insects engaged in
transporting the pollen from flower to flower. We may draw attention
to an example here and there. Each spherical grain of the Passion-flower
(Passiflora, fig. 494) looks under a strong magnifying power like a beautifully
chased Indian bowl. In Lapageria, Cucurbita (the Gourd family, fig. 493),
and not a few other plants, the spherical grains are covered with spines.
In the Scots Pine (Pinus sylvestris, fig. 495) each grain is provided with
a pair of bladder-like wings, which stand out from the grain like goggle-
eyes. As the pollinating agent in this plant is the wind, the bladder-like
structure is a most useful contrivance.
In a good many plants, as the Evening Primrose ((Enothera biennis, fig.
492), Clarkia, Fuchsia, etc., clinging pollen is strengthened by the presence
of a sticky, structureless substance called viscin, which causes the grains to
FIG. 523. — TWAYBLADE (Listera ovata).
(a) lnto by] IE. Step.
FIG. 536. — GREEN-MAN ORCHIS (Aceraa
anthropophora).
The divisions of the long lip an
the human figure, the arched se
supposed to represent
epals f ormin
The arrangements are much like those
aing the head.
of the Purple
434
HUTCHINSON'S POPULAR BOTANY
instantly adhere to the intruding object, and when the insect withdraws
its head, the two pollinia are seen to be sticking up upon it like a pair
of clubbed horns. Moreover, the cement, which has remained viscid under
its membranous covering perhaps for many hours, now hardens with great
rapidity — a wonderful and indispensable provision, for were the pollinia to
fall sideways or backwards, their usefulness for purposes of cross-fertiliza-
tion would be at an end. Never-
theless, at their present angle they
are equally useless, for, on visiting
another flower, what can happen
but that the insect will push them
back into their old position ? This
danger is obviated by a beautiful
contrivance, which Darwin thus
explains : " Though the viscid sur-
face remains immovably affixed, the
apparently insignificant and minute
disc of membrane to which the
caudicle adheres is endowed with a
remarkable power of contraction . . .
which causes the pollinium to sweep
through about ninety degrees, al-
ways in one direction— viz., towards
the apex of the proboscis — in the
course on an average of thirty
seconds. . . . Now, after this move-
ment and interval of time (which
would allow the insect to fly to
another flower) . . . the thick end
of the pollinium is exactly in
position to strike the stigmatic
surface." Surely if evidence were
wanted for the argument of Design
in Nature, you have it here ! We
may add that Darwin is speaking
of the Purple Orchis (0. mascula') ;
but his remarks apply equally to
the^ Spotted Orchis.* The plants are closely related, and the manner of
their pollination is the same in all essentials ; indeed, throughout the genus
Orchis, but little variation of the organs will be found.
The genus Orchis is not the only group of orchideous plants containing
species which are unprovided with true nectaries. The wonderful Catasetum
* Indeed, to two other British Orchids -viz., the Green-winged Orchis (0. morio) and the
Marsh Orchis (0. latifolia).
Photo by]
FIG. 537. — PURPLE ORCHIS (Orchis mascula).
An early spring Orchis with red-purple flowers whose arrange-
ments for pollination are very similar to those of the Spotted
FIG. 538. — FRAGRANT ORCHIS (Habenaria conopsea).
A plant of the downs and dry pastures, with a spike of very fragrant bright rose-red or purple flowfrs, which have
a long and slender spur. The" spur is half filled with nectar and specially adapted to the long tongues of butterflies and
moths. The litter appear to be attracted chiefly to the form with white flowers. EL-ROPE, N. and W. ASIA.
435
436
HUTCHINSOX'S POPULAR BOTANY
tridentatum and its female, the Monachanthus,* are further examples (fig. 507),
The cup or labellum — which in other species is usually the nectar receptacle
— is singularly inverted in the varieties specified, and thus is altogether
precluded from fulfilling that purpose. Yet, since the sexes stand on
separate plants, insects must be
attracted to the flowers in order
to secure pollination : and insects,
like beings of a higher order, will
not work except for reward. Dar-
win was the first to point out that
the labellum itself, which in these
varieties is thick and fleshy and
of " a pleasant nutritious taste,"
probably affords food to its insect
visitors, and thus answers the pur-
pose of nectar, just as do the tubes
in Orchis maculata and 0. mascula.
His surmises have been abundantly
verified.
Darwin regarded the genus
Catasetum as " the most remark-
able of all Orchids." They possess
the extraordinary power of forcibly
expelling their pollinia when a
certain part of the flower — the
horns or antentice of the column
(fig. 508, a??-)— is touched; and
therein lies their extraordinary
interest. Observe how the band
or pedicel of the pollinium (6),
which connects the disc (d) with
the pollen-masses (y>\ is curved
about the projecting rostellum.
This pedicel is in a high state of
tension. When either of the taper-
[P. Step.
FIG. 539. — GREEN-WINGED ORCHIS
(Orchis morio).
A plant frequently mistaken for the Purple Orchis, but distin-
guished at a glance by the parallel frreen lines along the sepals
and absence of purple spots from the leave-.
* So dissimilar is the female flower of
Catasetum tridentatum from the male
that it was long regarded as belonging
to a distinct genus, Monachanthus, and
styled Jf. viridis. Singularly enough, C.
tridentatum also bears hermaphrodite flowers, which differ no less in appearance from
the male and female forms than do those from one another. Hence the phnts producing
them were classed with a third genus, Myanthus, under the specific name barbatus. But
a plant was discovered bearing flowers of the three supposed genera on one spike, and so
the true state of things was recognised, and revision of names made accordingly.
SOME PLANT MARRIAGES
437
ing sensitive projections or antennae is touched (and bees visiting the flower
to gnaw at the labellurn inevitably come in contact with it), " the edges of
the upper membrane of the disc," says Darwin, " which are continuously
united to the surrounding surface, instantaneously rupture, and the disc
is set free. The highly elastic
pedicel then instantly flirts the
heavy disc out of the stigmatic
chamber with such force that the
whole pollinium is ejected, bring-
ing away with it the two balls of
pollen, and tearing the loosely
attached spike-like anther from
the top of the column (fig. 509).
The pollinium is always ejected
with its viscid disc foremost."
The force of the discharge will
sometimes send the pollinium a dis-
tance of two or three feet. One
of the attendants at Kew Gardens
told the writer that he was once
severely rated by a lady who had
been struck in the face by the
pollinium of Catasetum saccatum,
and had come to him with the disc
yet sticking to her cheek! Such
experiences are not uncommon.
Lord Avebury saw a flower of
Catasetum, callosum precipitate its
pollinium a distance of three feet,
when it hit a pane of glass and
adhered to it. " From the large
size of the flower, more especially
of the viscid disc, and from its
wonderful power of adhesion," says
Darwin, " we may safely infer that
the flowers are visited by large
insects. The viscid matter sticks
so firmly when it sets hard, and
the pedicel is so strong (though
very thin and only one-twentieth of an inch in breadth at the hinge)
that to my surprise it supported for a few seconds a weight of 1,262
grains — that is, nearly three ounces ; and it supported for a considerable
time a slightly less weight." Needless to say, no effort which an insect
thus encumbered could exert would remove the disc and pedicel ; " but the
Photo by] [E. Step.
FIG. 540. — BIRD'S-XEST ORCHIS
(Neottia nidus-avis).
An Orchis without leaves and with yellow-brown tlowers. The
roots take the form of a mass of thick fibres whose interlac-
ing is supposed to look like a bird's nest.
438
HUTCHINSON'S POPULAR BOTANY
caudicles are ruptured without much, difficulty, and thus the balls of pollen
would be left on the viscid stigmatic surface of a female flower/'
In striking contrast to the Catasetums are those Orchids which secrete
great quantities of nectar, like Coryanthes. The sweet fluid secreted by
the strange-looking horns of Cory-
anthes macrantha, for example, drips
so plenteously into the bucket-
shaped portion of the labellum at
the period of flowering that it half
fills the bucket— indeed, would
quite fill it, were it not that the
receptacle is provided with an
overflow spout ! Above the bucket
is a hollow chamber, walled and
ceiled with fleshy ridges and pro-
vided with two side entrances.
" The most ingenious man." says
Darwin, "if he had not witnessed
what takes place, would never
have imagined what purpose all
these parts serve. But Dr. Criiger
saw crowds of large humble-bees
visiting the gigantic flowers of
this orchid — not in order to suck
nectar, but to gnaw off the ridges
within the chamber above the
bucket; in doing this they fre-
quently pushed each other into
the bucket, and their wings being
thus wetted, they could not fly
away, but were compelled to crawl
out through a passage formed by
the spout or overflow. Dr. Criiger
saw a continual procession of bees
thus crawling out of their invol-
untary bath. The passage is nar-
row, and is roofed over by a column,
so that a bee, in forcing its way
out, first rubs its back against the
viscid stigma, and then against
the viscid glands of the pollen-masses. The pollen-masses are thus glued
to the back of the bee which first happens to crawl out through the passage
of a lately expanded flower, and are thus carried away. When the bee, thus
provided, flies to another flower, or to the same flower a second time, and
Photo by]
FIG. 541. — PYRAMIDAL ORCHIS
(Orchis pyramidalia).
Somewhat like the Fragrant Orchis, but with larger flowers.
The flower-spike is at first pyramidal. The long spur contains
no .nectar, and visiting insects have to suck at the lining
membrane.
P/wto by]
FIG. 542. — YUCCA PLANT ( Yucca gloriosa).
The fertilization of the Yucca— fully described in the following pages— is one of the wonders of plant life
439
440
HUTCHINSON'S POPULAR BOTANY
is pushed by its comrades into the bucket, and then crawls out by the
passage, the pollen-mass necessarily first comes into contact with the
viscid stigma, and adheres to it, and the flower is fertilized. Now at
last we see the full use of every part of the flower — of the water-secreting
horns, of the bucket half full of
water, which prevents the bees
from flying away, and forces them
to fall out through the spout, and
rub against the properly placed
viscid pollen-masses and the viscid
stigma."
A gardener of long experience
in Orchid culture informs us that
Stanhopea haseloffi, which belongs
to an allied genus, is cross-pollin-
ated in the same way as Coryanthes,
save that the half-drowned bees
fall out of the bucket, and strike
against the pollinium in falling.
The subject of insect-pollina-
tion is inexhaustible, yet even the
slightest sketch would be inadequate
that failed to contain some refer-
ence to the fertilization of the
Yucca-plant. It is nearly forty
years since Professor C. V. Riley,
of- Missouri, first announced the
method of pollination of the
Yuccas by a little white moth,
which he christened Pronuba yuc-
casella. Since that time much has
been written on the subject, and
in 1892 Dr. Riley published a valu-
able monograph on Y^ucca polliiia-
_ . tion, from which we have gleaned
Photo bul
[E. Step.
FIG. 543. — MUSK ORCHIS (Herminium
monorchis).
\ little-known Orchid with ?reen flowers, which secrete no
aectai— it has no spur— but gives off the odour of musk in
the evening for the attraction of small beetles.
most of the particulars given below.
The monograph, which extends to
sixty large octavo pages, and is
fully illustrated, is included in the
third annual report of the Missouri Botanical Garden.
The Yuccas are a very interesting genus of plants of the lily family,
comprising numerous species and even sub-genera, all characterized by
anthers not reaching anywhere near the stigma ; so that fertilization
unaided can take place only by the merest accident. These plants, in fact,
SOME PLANT MARRIAGES
441
FIG. 544. — MAESH-CALLA
(Calla palustris).
A marsh snail is seen to be climbing t'.ie stem.
Snails have been observed to pollinate the flowers.
depend for their very existence on certain
little white moths, belonging to the im-
portant group Tinseina, and to the genus
Pronuba. Thus the Yuccas affords an in-
stance — apparently the only known instance
— of plants which are dependent on a single
species for pollination.
The common Yuccas of the United States
are forms of Yucca filamentosa, and their
white-winged pollinator is the commoner
Yucca moth, Pronuba yuccasella (fig. 512).
During the daytime this moth, either singly
or in pairs, may be found resting with
folded wings within the half-closed flowers.
After sundown it is to be seen flitting
swiftly from plant to plant and flower to
flower ; the dusky nature of the hind wings
and of the under surface of the front wings
almost completely off-setting and neutralizing, when in motion, the upper
silvery whiteness of the latter. This is the male insect. The female is
busily at work most of the time in the flowers; for on her devolves a
double duty, which leaves no leisure for these nocturnal flittings. As a
part of the maternal task of continuing her race, she must act as foster-
mother to the plant in order to ensure a proper supply of food to her
larvae, which, as we shall presently see, feed on its seeds. Her activity
begins soon after dark, and consists at first in assiduously collecting a load
of pollen. She may be seen running to the top of one of the stamens, and
bending her head down over the anther, stretching her maxillary tentacles,
which are wonderfully modified for the purpose, to the fullest extent ; and
using her palpi to scrape the pollen from the anthers towards the tentacles.
After gathering a sufficient supply, and shaping it into a pellet twice or
thrice the size of her head, she sets off
for another flower, leaving the despoiled
blossom to be pollinated by some other
individual of her race. On entering the
new flower, she takes up a favourable
position, and after resting motionless for
a short time, plunges her lance-like ovi-
positor into the soft tissue of the pistil,
and conducts her first egg to its destina-
tion. Mark what follows. No sooner is
the ovipositor withdrawn than the moth
runs up to the top of the pistil, thrusts the
pollen into the stigmatic funnel, and
FIG. 545.— MARSH-CALLA (Calla
palustris).
A 8togle fiower " the epadlx and
442 HUTCHINSON'S POPULAR BOTANY
rams it down effectually with a to-and-fro motion of her head. If. as is
commonly the case, another egg is deposited in the same pistil, and
after that a third, each act of oviposition is succeeded by a fresh act of
pollination ; but on each occasion a. different notch of the style is selected,
and thus a supply is ensured for the ovules in each carpel. How perfectly
the insect does its work may be gathered from the fact that artificial
attempts to cross-fertilize the Yuccas by means of brush-pollination are
rarely, if ever, successful.
The larva hatches in about a week, and at first appears to live on the
degenerate and swollen ovules : but finally it enters one that is developing.
In this state it undergoes three different moults, its colour meanwhile
changing from a translucent white to a rosy hue ; and with the ripening
of the seeds, the larva attains its maturity. Just about the time the fruits
are hardening and ready to dehisce, and the seeds are already coloured,
the maggot bores a passage through
the pod, makes its way to earth,
and, tunnelling several inches below
the surface, spins in its under-
ground fastness a tough silken
cocoon intermixed with the soil.
In this condition it remains during
the autumn, winter, and spring
months, and only assumes the
chrysalis state a few days before
the blooming of the Yuccas. The
FIG. 546.-BALSAM (Impatiens). chrysalis is armed with spines on
The flowers are adapted to the visits of humble-bees. At first ii -i i i i i -i f
the stamens mask the pistil and stand in the entrance to the the head and DaCK, by means OI
wer- which it works its way to the sur-
face, and in due time issues forth
a perfect insect ; henceforth to live its little life above ground, and, in
conjunction with some chosen companion of the other sex, to carry on the
useful work which its parents have carried on before it.
Of animals outside the great class Insecta which aid in bringing the
reproductive elements of plants together, the chief are snails and birds.
Delpino, indeed, divides the plants fertilized by animals into three groups :
I. Omithophilce, or bird-lovers ; II. Entomophilce, or insect-lovers ; and III.
Malacophilce, or snail-lovers. Groups I. and III. remain to be spoken of.
The plants fertilized by the agency of snails are comparatively few
in number. The Marsh-calla or Snake-root (Calla pahwtris, figs. 544, 545)
may serve as an example; though its chief pollinators are carrion-loving
flies, which are attracted to the flowers by their offensive smell. Pond-
snails, however, crawl up the partially submerged stem to the spadix,
receive pollen from the anthers of the lower ring of flowers, and, continuing
their journey, pollinate the female flowers higher up.
Photo by}
FIG. 547. — Alocasia spectabilis.
[F. C. Taylor.
An herbaceous plant belonging to the extensive order Aroideie. The largp radical leaves of this plant are beautifully
variegated. In one species the flowers have been observed to be pollinated by snails.
443
444
HUTCHINSON'S POPULAR BOTANY
In Alocasia odora, a plant be-
longing to the same order (Aroidece),
snails enter the spathe by a narrow
opening, lose their way when inside,
and in their purblind efforts to re-
gain the entrance, dust themselves
with pollen, which they convey to
the stigmas of younger plants.
Delpino was of opinion that the
snails " are poisoned by an irritant
secretion within the chamber of the
spathe, and are so prevented from
devouring the flowers " after cross-
pollination has been effected. The
same naturalist has recorded obser-
vations on the snail-pollination of
Rhodea japonica and of Cypripedium
caudatum, and states of the former
that the flowers which proved fer-
tile were always those over which
snails had crawled.
Then as to birds. In tropical,
and even in temperate America,
sun-birds and humming-birds are the
welcome guests of many flowers.
" Chiefly in the months of July and
August," says Waterton, ': the tree
called Bois Immortel, very common in Demerara, bears abundance of red
blossom, which stays on the tree for some weeks ; then it is that most of the
species of humming-birds are very plentiful. The wild red Sage [? Salvia
coccinea] is also their favourite shrub, and they buzz like bees round the
blossoms of the Wallaba-tree [Eperua falcata]. Indeed, there is scarce a
flower in the interior, or on the sea coast, but what receives frequent
visits from one or other of the species."
It will be noticed that the plants named by Waterton in the above
passage all bear red flowers ; and many naturalists have pointed out that
humming-birds appear to have a penchant for scarlet. Fortunately— both
for visitors and visited, for bird guests and plant hosts — scarlet blossoms
are plentiful in the primeval forests of Central America, where humming-
birds chiefly have their home. In those densely vegetated regions may
be seen the flaunting reds of the lianes and epiphytes of many widely
differing genera, with the dazzling scarlets of Begonias and Fuchsias, of
Sages and Lobelias, of Browneas and Erythrinas, the very construction
of whose blossoms in not a few instances forbids their being rifled by
FIG. 548. — SECTION OF LAPAGEEIA.
The nectary is at the base of the flower, that is, the upper
part as it hangs.
SOME PLANT MARRIAGES
445
insects. Numbers of such flowers take a lateral direction, and are un-
provided with landing-stages ; for humming-birds never alight when
feeding, but sip the nectar as they hover with widespread wings at the
mouths of the flowers. The absence of ridges, knobs, and fringes, which
serve so useful a purpose in insect-pollinated flowers, is also to be remarked.
Darwin, in his Cross and Self-fertilization of Plants, gives an interesting
summary of the cases of bird-pollination known to himself, which it will be
useful to quote. "In South Brazil," he says, " humming-birds fertilize the
various species of Abutilon, which are sterile without their aid. Long-
beaked humming-birds visit the flowers of Brugmansia, whilst some of the
short-beaked species often penetrate its large corolla in order to obtain
the nectar in an illegitimate manner, in the same way as do bees in all parts
of the world. It appears, indeed, that the beaks of humming-birds are
specially adapted to the various kinds of flowers which they visit ; on the
Cordillera they suck the Salvia, and lacerate the flowers of the Tacsonice ;
and in Nicaragua Mr. Belt saw them sucking the flowers of Marcgravia
and Erythrina, and thus they carried pollen from flower to flower. In
North America they are said to frequent the flowers of Impatiens. I may
add that I often saw in Chili a Mimus with its head yellow with pollen from,
Photo by]
FIG. 549. — YARROW (Achillea ptarmica).
A small Composite that is specially attractive to the little bees of the genus Prosopis.
[K. Step.
446
HUTCHINSON'S POPULAR BOTANY
as I believe, a Cassia. I have been assured that at the Cape of Good Hope,
Strditzia is fertilized by the Nectarinidse [the Sun-birds]. There can hardly
be a doubt that many Australian flowers are fertilized by the many honey-
sucking birds of that country. Mr. "Wallace remarks that he has ' often
observed the beaks and faces of the brush-tongued lories of the Moluccas
covered with pollen.' In New Zealand, many specimens of the Anthornis
melanura had their heads
covered with pollen from
the flowers of an endemic
species of Fuchsia."
A later observer. Pro-
fessor W. Trelease, of the
Missouri Botanical Garden,
gives a yet longer list, and
states that an Alabama
planter once laughingly said
to him : " You'll have to note
every conspicuous flower if
you want a full list of those
visited by the humming-
birds." On several occa-
sions the professor watched
the ruby-throated hum-
ming-bird extracting nectar
from the glands at the base
of the involucre in cotton-
flowers (Gossypium) ; and he
found that humming-birds
were largely— it' not exclu-
sively—used in the crossing
of Malvaviscus, a scarlet-
flowering genus of tropical
shrubs.
The observations of a
still younger botanist, Mr.
William Sugden. of Michi-
gan, are equally worthy of
attention. Mr. Sugden tied
bags over the flower-buds of Impatiens fulva, and also over flowers which
had opened, but before the stamens (whose anthers in the first stage form
a covering over the pistil) had disappeared. In neither case were good
seeds produced, though artificial crossing under similar conditions was suc-
cessful. Flowers of the same species, unconfined in this manner, but
divested of their petals, set no seed whatever; and this was also the result
IE. s:cp.
FIG. 550. — WHITE CAMPION (Lychnis vespertine).
Its white flowers open in the evening, when it becomes sweet-scented for the
attraction of night-llym- moths. Nectar is secreted hy the base of the
ovary. In the daytime the flowors look faded or dead.
[E. Step.
FIG. 551. — HEATHEB OB LING (Calluna vulgaris).
The most conspicuous part of the flower is the rosy calyx, the corolla being quite small. The leaves are very minute
and like overlapping scales. They are specially adapted to resist cold. EUROPE, w. SIBERIA, AZORES, GREENLAND,
N. AMERICA.
447
448
HUTCHINSON'S POPULAR BOTANY
even when the nectar-gland only was removed. Mr. Sugden noticed also
that black bees, which visited the free and unmutilated flowers in large
numbers, hardly ever touched an anther or pistil, so that they were of
no use as pollinating agents. The visits of wild bees and the common
honey-bee were equally profitless to the flowers ; and even when a humble-
bee hit pollen in its
plunges to get at the nec-
tar, it left the plant after
trying a single flower. With
humming-birds the case was
quite different. Every time
one of these little creatures
thrust his arrowy beak into
a flower of the first stage,
his head would strike the
anthers and become dusted
with pollen. On visiting a
flower in the second stage
— i.e. after the withering of
the crown of anthers — the
bird's head would come in
contact with the exposed
stigma, with the inevitable
result that some of the pollen
would be left upon it.
Of the plants which lay
themselves out for cross-
fertilization, but which do
not invite the co-operation
of small animals, some em-
ploy water as their agent,
and others the wind. Ex-
ternal aid for the purpose
in question may therefore
be of three kinds, and the
plants which require those
agencies to bring their re-
productive elements to-
gether may be grouped
under one or another of the following heads : Zoophilce, or animal-lovers ;
Hydrophilw, or water-lovers; and Anemophilce, or wind-lovers.
Wind- and water-pollinated plants are rigid economists, except in the
matter of pollen.. They have no attractive odours, no bright petals, no
nectar. Birds and insects may be allured by these things, but not so wind
Photo by]
FIG. 552. — ASPEN (Populus tremula).
IE. Step.
rhesumple flowers are borne in long catkins, which appear before the leaves
to allow pollination by the leaves. Those shown in t:,e photo are the male
catkins.
CERVANTES' ODONTOGI.OT fOdonioplof«,,m cfrcanleni).
The Odontoglots are a beautiful genus of epiphytal Orchids inhabiting the tropical regions of America. Over a hundred
species are known. Cervantes' Odontoglot is a native of Mexico. Each pseudo-bulb produces a single leaf and a spike
of from three to five n»y-lilac flowers. Natural size.
SOME PLANT MARRIAGES
449
and water, which, having no senses to be appealed to, would be unaffected
by colour, sweets, or scent. Yet being wasteful carriers, these agents
require abundance of pollen ; and, if water is to be the vehicle of trans-
mission, the pollen must be either lighter than the water or of like specific
gravity : if wind be the agent, the pollen must be smooth, light, and
incoherent. In the vast majority of cases these conditions are found to
be wonderfully fulfilled.
Of hydrophilous plants some are adapted for fertilization under the
water: and these
are provided with a
pollen of like speci-
fic gravity to the
surrounding fluid ;
others are adapted
for fertilization at
the surface, and the
pollen of these —
unless borne upon
a floating raft — is
specifically lighter
than the water.
The Grass-wracks
(Zoster a) are re-
markable for pro-
ducing a pollen the
grains of which do
not, like the gener-
ality of pollen-
grains, burst in
water. Moreover,
the grains assume
the form of elon-
gated cylindrical
tubes on quitting
the anthers, which
greatly facilitates their conveyance through the water to the threadlike
stigma of the flowers. Something almost analogous takes place in certain
cryptogamic plants — notably the Floridecu or Red Seaweeds — where the
male cells are neither motile nor provided with hairs, but are borne about
passively by currents of water till they attach themselves to the slender
projecting terminal cells of the female organs.
The Sea Ruppia or Tassel-grass (R. maritima), closely allied to Zostera,
is a widely distributed plant adapted for pollination on the surface of water.
At the period of maturity the submerged flower-stalk lengthens, and the
n—11
Tlioi
spike
FIG. 553. — SCOTS PINE (Pinus sylvestris).
e flowers [are here shown spirally arranged
; ar
separate brandies.
spirally
forming a" cluster. Tue female (lowers are b
[E. Step.
spikes and a large number of
ne on the same tree, but on
450
HUTCHINSON'S POPULAR BOTANY
plant lifts its head above the marsh or salt-pool which it inhabits. Lengthen-
ing continues until the object is attained, but thereupon ceases, no matter
what the depth or shallowness of the water. The Rev. Gerard E. Smith,
a botanist well acquainted with the plant, has thus sketched the process :
" The anthers are vesicular and buoyant : as they swell and become mature,
the membranous sheath enclosing them is distended, and the whole is
brought to the sur-
face of the water.
The flower-stalks are
rapidly lengthened,
the flowers quit the
sheath, which then
becomes a bladder,
and aids the eleva-
tion of the spike an
inch above the
water. Presently
the anthers burst,
the vesicle loses it&
buoyancy, and the
flower-stalks, bear-
ing the fertilized
stigma, sinks within
the bosom of the
parent plant." It
will be noticed that
the flowers both of
Tassel-grass and
Zostera are small
and inconspicuousr
and possess neither
calyx nor corolla.
Large blossoms and
Plinto by]
FIG. 554. — SCOTS PINE (Pinus sylvestris).
The female flowers are seen at the tips of the shoots. The cones are soon formed, hut
.
the seeds do not ripen until the second year.
bright colours would
be useless to plants
which rl P r> P n d 0 11
water for the distri-
bution of their pollen, just as they are to the wind-pollinated forest trees,
Doubtless the most curious of hydrophilous plants is the Italian Eel-gi'ass
(Vallisneria spiralis), which is also one of the greatest marvels of the
vegetable world. It is distributed throughout Southern Europe, and grows
in still water. Our illustration (fig. 515) shows both the male and female
plants, with their strap-shaped leaves and flowers in various stages : the male
plant is on the right, the female on the left. The pistillate (i.e. female \
451
452
HUTCHINSON'S POPULAR BOTANY
flowers are borne on long stalks (fig. 517, «), each of which, whilst the
stigmas are maturing, is enveloped in a kind of bladder. The staminal
flowers are similarly invested, but they grow in thick clusters, and one sheaf
suffices for all the individuals of a cluster. Each of these male inflorescences
is borne on a short rachis (fig. 517, b, c), which remains short to the end of
the chapter ; but at a certain stage the pedicels of the female flowers
lengthen to an extraordinary extent, and presently reach the surface of the
water. The floral sheaths in the plants of both sexes meanwhile fall apart,
and everything betokens readiness for nuptial celebrations.
But now an interesting problem arises. While the female flowers, held
by their thread-like pedicels, are floating restfully on the bosom of the
water, the male flowers are anchored far down; below by their diminutive
stalks to the short axes. How are the sexes to be>brought together? The
problem is solved in
a very wonderful,
and, at the same time,
a very simple man-
ner. The submerged
male flower-buds de-
tach t h e m s e 1 v e s
spontaneously from
their axes, and, being
lighter than the
water, ascend to the
surface. Here the}7
drift about for a
while ; then open,
and, twisting back
their three sepals in
an ingenious man-
ner, so as to make a
float, bring into view
the two perfect sta-
mens, which now
stand well out of the
water like a pair of
snail's horns. These
miniature floats, as
Kerner beautifully
remarks, " are blown
hither and thither by
v I*** the wind, and accu-
FIG. 556. — OAK (Quercus robur). ' . ,
These are the male flowers in long, loose catkins. The female flowers-borne by the mulate in tne neigh-
same tree— are like little buds, and not so noticeable, bourhood of fixed
SOME PLANT MARRIAGES
453
bodies, especially in
their recesses, where
they rest like ships
in harbour. When
the little craft hap-
pens to get stranded
in the recesses of a
female Yallisneria
flower, they adhere
to the trilobed stig-
ma, and some of the
pollen-cells are sure
to be left sticking to
the fringes on the
margins of the stig-
matic surfaces."
Pollination having
been thus effected,
the pedicel of the
fertilized liower con-
tracts spirally and
the ovary descends
to the bottom of the
water to perfect its
seeds.
We come now to
the anemophilous or
wind-po llin ate d
plants. Most of our
forest trees, and the
grasses, are exam-
ples of this group.
Wind is far more ex-
tensively employed
as a pollen-carrier than water, but is not so bus}' an agent as insects.
Flowers which lay themselves out for wind-pollination are characterized
by abundance of smooth and dusty pollen ; by stigmas specially adapted
for catching and retaining it ; and, as we have seen, by an absence of
bright-coloured floral envelopes, perfumes, and honey. ' " The amount of
pollen produced by anemophilous plants," says Darwin, ': and the distance
to which it is often transported by the wind are both surprisingly great.
Mr. Hassal found that the weight of pollen produced by a single plant
of the Bulrush (Typha) was 144 grains. Bucketfuls of pollen, chiefly
of Coniferce and Graminew, have been swept off the decks of vessels near
Photo by] [E. Step
FIG. 557. — COTTON-GRASS (Eriophorum polystachion).
The Col ton-grasses are Sedge-like plants that cover vast areas of boggy moorland. The
" cotton " really consists of delicate bristles which represent the petals of other flowers.
454
HUTCHINSON'S POPULAR BOTANY
FIG. 558. — POL-
LEN-GRAINS OF
GREAT PANI-
CLED SEDGE (Ca-
rex paniculata).
the North American shore: and Mr. Rile}' has seen the
ground near St. Louis, in Missouri, covered with pollen, as
if sprinkled with sulphur : and there was good reason to
believe that this had been transported from the pine-forests
at least 400 miles to the south. Kerner has seen the snow-
fields on the higher Alps similarly dusted ; and Mr. Blackley
found numerous pollen-grains, in one instance 1.200, adher-
ing to stick}- slides, which were sent up to a height of from
500 to 1,000 feet by means of a kite, and then uncovered
by a special mechanism." A shower of pollen which fell
in Inverness-shire in the year 1858 (our authority is Professor
Ainsworth Davis) covered the ground to a depth of half an inch.
Of the three great classes into which the Flowering Plants are divided —
namely, Monocotyledons. Dicotyledons, and Gj-mnosperms — one class, the
last named, is entirely composed of wind-pollinated plants. The Gymiio-
sperms derive their names from the fact that their ovules are not contained
in an ovary — they are naked. The flowers, which are unisexual and without
calyx or corolla, would stand but a poor chance of perfecting their seeds
were it not for the kindly offices of the wind.
The Scots Pine i Pinus sylvestris] offers a good example of the wind-
pollinated gymnosperm. Its inflorescences are cones, the male cones, which
grow in clusters, being much smaller than the female. In the month of
June the anthers open, and discharge their winged pollen, which is furnished
with microscopic air-bladders (fig. 495), into the grooved backs of the
membranous anther-scales, where it lies ready for the breeze to scatter it.
Meanwhile the female cones get ready for the " sulphur shower,'' and being
unprovided with any stigma or subsidiary stigmatic appendage, the naked
ovules exude a viscid substance which holds fast the pollen that falls in their
way, and which, as it dries up, draws the pollen through the micropyle into
the interior of the ovule. The fertilized ovules do not arrive at maturity—
that is, become ripe seeds— for two years; and hence every female cone
may be said to have three periods, which correspond with three distinct
stages in the development of the inflores-
cence. In the first period the cone is
green and small, and is seated on one of
]ff jjj the very 3'oung shoots ; in the second
period (i.e. at the beginning of the second
yean the cone is larger, but still green,
and of course the shoot has become older :
in the third period — the cone being now
two years older— the scales have become
brown and woody, and the seeds are ripe.
Among the Angiosperms (Dicotyledons
and Monocotyledons) the contrivances for
FIG. 559. — POLLEN-GRAIN MAGNIFIED,
Showing the inline bursting through the
extine as the pollen-tube.
Photo 6i/]
FIG. 560. — GREAT WATER DOCK (Rumex hydrola-pathum).
The largest of our species of Docks, growing by river-sides and attaining a height of five or six feet. The wind -
pollinated Mowers are minute, but conspicuous by being combined in b>rge panicles, which give it a very handsome
and striking appearance. Its distribution is restricted to Europe.
455
[E. Step.
456
HUTCHINSON'S POPULAR BOTANY
wind-pollination are more elaborate than among the Gymnosperms. " The
anemophilous angiosperms," says Hermann Miiller, " have for the most
part enormously developed stigmas, which project in the form of long tails,
brushes, laminae, or discs; their male flowers are very seldom immovable,
but are generally easily shaken by the wind, either the axis of the male
inflorescence or the peduncle of the male flowers, or the filaments them-
selves, being long and pendulous ; in some cases the stamens are explosive,
and project all the pollen into the air."
We may take as our first example the flowers of the Hazel (Corylus
avellana). Most people
are familiar with the
long pendulous " lambsr
tails," as the children
call them, which make
their appearance on the
Hazel in the autumn,
and which, in the South
of England, open in
January or February.
These are the male in-
florescences or catkins *
(fig. 519). The female
inflorescences are the
small cone-like growths
(strobiles}, sometimes
rather loosely described
as "female catkins,"
which appear in the
axils of the new shoots.
The tiny groups of
crimson threads project-
ing from the tops of the
strobiles are bunches of
FIG. 561. — HAZEL (Corylus avellana).
Abnormal male ilower
origin and ends in
A single catkin ha
hunch of twenty- fiv
•anclied at half an inch from" its
iort catkins. Natural size. "
forked stigmas. The
anthers open while the
hazels are still bare of leaf, and roll out their pollen into the trough-like
depressions of the flower's scaly bracts, which retain it "until the tassels
are set swinging by a gust of wind." Then the yellow dust, with no foliage
to impede it, is blown hither and thither, and the stigmas of a great number
of female flowers are sure to get pollinated.
That pendulous flowers, no less than pendulous inflorescences, should
facilitate the scattering of pollen by the wind goes without the saying. Many
species of Rumex, the genus to which our Broad-leaved Dock and Sheep's-
* The more technical name for a catkin is an amentum.
SOME PLANT MARRIAGES
457
sorrel (R. obtusifolius and acetosa) belong, are of this kind, and are
anemophilous. In the Alpine Dock (R. alpinus) and the Garden Sorrel
iR. scutatus). the anthers are pendulous at the ends of the delicate filaments,
and the pollen-dust is shaken out of them in the lightest breeze.
Most of the Sor-
rels, however, and
with them the
Grasses, Sedges,
Rushes, and "Wild
Plantains, are em-
braced under a far
more common va-
riety of anemophil-
ous flowers— name-
ly, the forms with
long stamens. In the
Rye-plant (Secale
cereale], for instance,
the essential organs
protrude freely from
the widely expanded
flowers, and cross-
pollination is effected
on a large scale by
the wind. Delpino
has some interesting
observations on the
Ribwort Plantain
(Plantago lanceolata)
which seem to show
that the flowers of
this species are in
process of develop-
ment from an ane-
mophilous to an en-
tomophilous form.
He says : " One form,
with a strong and
very tall scape, and
very broad white
anthers which quiver
in the wind, grows
in meadows and is
exclusively anemo-
Fio. 562. — LARGE PLANTAIN (Plantago major).
An abnormal form with the flowc
edges. The form is ec
spikes hearing
tant, being re
eroiis large bracts with purple
lueed true from seeds.
458
HUTCHINSON'S POPULAR BOTANY
philons, for I have never seen it visited by insects. The second form grows
on the hills, and has a much shorter scape ; it also is essentially anemo-
philous. I once saw a species of Halictus on a spike, trying to get pollen ;
but the structure of the flower is so unfitted for pollen-collecting, that
great part of the
pollen fell to the
ground witho u t
benefiting either the
plant or the insect.
Finally, the third
form is dwarfish and
confined to the moun-
tains ; it has the
shortest spike and
filaments : on mea-
dows in the Apen-
nines at Chiavari I
have seen bees in
numbers flying from
one flower to another
of this variety, col-
lecting the pollen and
performing cross-
fertilization.
"This, therefore,
is a form of Plantago
which hangs be-
tween the anemo-
philous and entomo-
philous conditions,
and is capable of be-
ing fertilized equally
well by the wind and
by the bees. If the
filaments became
stiff and coloured,
and the pollen-grains
adhesive, while the
anthers lost their pe-
culiar quivering, we should have before us the passage from anemophilous
characters, the evolution of an entomophilous from an anemophilous species.
"This hypothetical transition has actually occurred. Plantago media
is a form that has become entomophilous ; the filaments have become
pink, the anthers are motionless, the pollen-grains have become more
FIG. 563. — COMMON SORREL (Rumex aceto
A common plant formerly
of potash. The sex
abounding in oxalate
carried by the wind.
[E. Step.
FIG. 564. — FALSE CYPERUS (Carex pseudocyperus).
One of the fine? t of oxir Sedges, growing to a height of about three feet. The stems are three-side)
e Iges. The spikelets take the form of long drooping catkins, two to three inches Ion*. The male
solitary ; the females in clusters of four or five. Wind-pollinated. TKMI'ERATE REGIONS CEJ.
4")9
460
HUTCHINSON'S POPULAR BOTANY
aggregated, and it is visited regularly
by Bombus terrestris, as I have observed
at the same spot (Chiavari) in the
Apennines."
Explosive forms of anemophilous
flowers are met with in the Nettle
family (Urticacese) and a few other
species. The Great Nettle (£7. dioica.
fig. 516) is an excellent example. Here
the sexes are on different plants, and
the flowers are small, green, and in-
conspicuous. While the male flower is
unopened, the stamens, which are fur-
nished with an elastic tissue, curve in-
wards; but as the llower matures, they
gradually become dry, and, a result of
this dryness, spring outwards, spurt-
ing the pollen into the air. In this way
they assist the wind in disseminating
the fecundating dust.
The Wall-pellitory (Parietaria ojfiei-
nalisi, a common weed on old walls
and in dry waste places, scatters its
pollen in a similar manner. The coiled-
up stamens are highly irritable, and at
the proper time force asunder the seg-
ments of the calyx which hold them
down and iiirt out their pollen. It is
a remarkable fact that, in the her-
maphrodite flowers of this plant, the
brash-shaped stigma of the pistil falls
off before the anthers dehisce, and thus
self-pollination is prevented.
Closely related to the Nettles and
Wall-pellitory is the equally remarkable
Artillery-plant (Pilea microphylla}.
This is a small plant, with leaves re-
sembling those of Wild Thyme, and
minute dioecious flowers, common
enough in indoor ferneries. The Eng-
lish name refers to the copious dis-
charge of pollen when the stamens
straighten themselves— a phenomenon which may be artificially induced
by sprinkling the plant with water. The anthers empty themselves
Photo b>i]
FIG. 565.— WOOD SAGE (Teucrium
scorodonia).
The pale oclireous flowers are muc'.i visited by bees.
The purplish stamens after shoHin- their pollen bend
back to allow the pistil to occupy their former position
SOME PLANT MARRIAGES
461
instantaneously, the contents Hying out like the puff of smoke froin a
distant gun.
The only other group of wind-pollinated plants which need be noticed
here is that which comprises the forms ivith immovable flowers. In these
it is usual to find that provision is made for temporary storage of the
pollen should no icm^Z be stirring ivhen the anthers dehisce. For instance,
in the Arrow-grass (Triglochin palustre) the pollen is rolled into the deep
concavities of the perianth leaves : while in the Sea-buckthorn (Hippophut
rhamnoides) it is discharged into little bladders formed by the uniting
concave scales in which the stamens lie. Let a warm dry wind spring
up, and the bladders open by narrow chinks, and set free the pollen—
which, however, can only escape a little at a time. The Broad-leaved
Pond-weed (Potamogeton natans) is a good example of a wind-pollinated
plant with immovable flowers.
Here our chapter must close, though not for lack of matter to carry
us farther. The subject of the Pollination of Plants is inexhaustible, and
must ever remain so: for, in pursuit of the study, we are brought again
and again — as in the study of the Life of Plants — to the borders of the
Unknown Land. Here it is that questions press upon us which, as Sahleiden
Photo by]
FIG. 566. — HORNBEAM (Carpinus betulus).
The male flowers are in pendulous catkins two inches in len?th. The female flowers form a large spike, which
lengthens after fertilization to three or four inches, and becomes pendulous. Those shown are the male <
[/•;. Step.
462
HUTCHINSON'S POPULAR BOTANY
finely remarks, we can neither repel nor answer. "What has the wind to
do with the date-harvest of Bileduljerid, and with the sustenance of millions
of men ? What cares the gall-fly that on its activity depends the fig trade
of Smyrna, and the food or support of thousands of human beings? Or
does the beetle, whose theft facilitates the increase of the Kamschatkan
Lily, imagine that their bulbs shall be the means to save the whole popu-
lation of Greenland from starvation in the following hard winter ? If
FIG. 567. — SWEET CHESTNUT (Castama saliva).
The Ion- catkin marked (a) consists of male flowers ; those marked (ft) are fenules.
all this is the result of unsubstantial natural laws, whence this wonderful
interdependence and connection of subordinate forces, to bring to pass
events which have so deep an influence on the history of humanity ? We
do, indeed, see into the mechanism of the puppet; but who holds the
strings, and directs all its motions to one pat-pose? Here closes the office
of the naturalist, and, instead of answering, he turns from the world of
space and lifeless matter upward to where, in holy anticipation, we seek
the Ruler of Worlds."
Photo by] VIenr'-' Ininy-
FIG. 568. — GRAPE VINE (Vitis vinifera).
A. familiar cultivated plant that climbs by means of tendrils, and lias inconspicuous flower-Tof p ecu Ih reform.
The fruits are berries. Native of the Mediterranean region.
463
CHAPTER XIY
THE PROMISE OF THE PLAXT THAT IS TO BE
. . . Fruit and seed,
New loosed from thorn-bush, tree, and flaunting weed,
And now by wing, or scale, or plume up-borne,
Fare forth on pilgrimage.
WHEN water, wind, or animal (or, it may be. the unaided plant)
has fulfilled its function as an agent of pollination, the true
process of fertilization begins. The outcome of fertilization is the fruit.
In popular language the term "fruit" may mean many things, but
botanists usually confine it to the ripened pistil or ovary of a flower.
Possibly this use of the term is rather too exclusive. Kerner would
extend the definition to ;i everything which undergoes alteration after
fertilization either in the flowers or flowering axis," and urges that as
the changes in question are '• for the purpose of promoting the interests
of the embryo,'' whatever participates in this object is the fruit. However,
not to appear singular, we will abide by the definitions of the text-books,
and take it that a fruit is a ripened and developed ovary.
How does this ripening and development take place ? The accom-
panying figures will help us to
understand the process. Fig. 570
represents an ideal section through
a uniovular ovary just after pollin-
ation, a is the stigma, upon which
are six pollen-grains. The style (6)
widens into the ovary (cc), which
contains a single inverted ovule (d>
— the latter not shown in section.
We speak of the ovule as inverted
because the micropyle (g) is not at
the apex of the ovule, but, by a
twisting round of the whole ovule,
is brought close to the funicle or
point of attachment i. /).*
FIG. 569. — WHITE WATER-LILY (Castalia alba). * This is the commonest form of ovule,
A transverse section of the ovary, showing the ovules in the an(^ *S described as anatropOUS. It must
be carefully distinguished from the bent
484
THE PROMISE OF THE PLANT THAT IS TO BE 465
FIG. 570. — UNIOVULAR OVARIES.
before fertilization (the ovule not in section), (a) Stigma, upon which
Dvule (d); (J) stalk (funicle) of ovule;
The first diagram shows the ovary in secti
are six pollen grains ; (6) style ; (c c) ovary containing a single inverted
(a) aperture (micropvle) of ovule through which the pollen-tube enters. In the second diagram the letters a to g are :
above, (h) Antipodal cells; (k) central nucleus; (in) egg-cell (oosphere) from which, after fertilization, the embryo
plant is developed ; (nti) co-operating cells (synergida?) ; (p) pollen-tube entering the micropyle; (r) inner envelope
of ovule' (*) outer envelope of ovule. The space containing It, k, m, n is the embryo-sac; the pi
it (.r) is the nucellus.
rt surrounding
The second diagram shows the same pistil, but with the ovule also in
section. Observe the structure of the ovule, here represented at the stage
immediately preceding fertilization. Commencing from the outside, we
have first a coat or envelope (s) — the outer integument ; secondly, an inner
coat (r) — the inner integument ; and within that a mass of tissue (#), repre-
sented by the dark shading — the nucellus. Embedded in the nucellus is the
embryo sac, which contains an abundance of protoplasm, with large vacuoles
or campylotropow form, in which the ovule curves upon itself like a horseshoe, and so
brings the micropyle near the base. This is well seen in the Pea (fig. 571) and in the
seeds of Shepherd's Purse (Capsella bursa-pastoris). Straight or orthotropous ovules,
which have the funicle and nucellus in the same straight line, are common among the
Gymnosperms, and occur also in the Dock family. The Yew (Taxus baccata) offers an
excellent example of this form.
TI— 12
466
HUTCHINSON'S POPULAR BOTANY
FIG. 571. — CAMPYLOTROPUUS OVULE
OF PEA.
(m) Micropyle ; (/) funicle
and a central nucleus (k) : and in addi-
tion to the protoplasm, a number of small
cells (m. •}?, etc.). First and chief is the
egg-cell or oosphere * (m). from which, after
fertilization, the embryo plant is de-
veloped. Its two sister-cells (n n), which
co-operate in this work, are known as the
synergidce. They are situated somewhat
nearer the micropyle (g] than the oosphere.
and constitute with it the " egg appara-
tus." The three cells at the opposite end
of the embryo sac are the antipodal cells.
Soon after their formation each of the
antipodal cells becomes invested with a
cell-wall, but they appear to play no part
in any of the subsequent phenomena, and
their use we are not at present able to estimate.
Watch the process of fertilization. On putting forth its tube the pollen-
grain shapes a course down the loose conducting tissue of the style until it
reaches the micropyle of the ovule. The tube, it should be explained, is an
outgrowth of the inner coat or intine of the pollen-grain through the extine
or outer coat (fig. 559), and it bears at the end a reproductive nucleus, which
is in fact the male sexual cell or male gamete. Forcing its way down the
micropyle, the pollen-tube perforates the embryo sac, and then, opening at
the tip. allows the reproductive element— which has meanwhile divided to
form two male cells — to pass out. Thus released, the generative nuclei
traverse the synergidce — which thereupon shrivel and collapse— and, with
that, one of these male cells enters the
egg-cell and fuses with the female nucleus.
This is the act of fertilization.
The cell formed by the fusion of the
male and female nuclei is called the oosperm
or embryonic cell : and from this cell (as
the latter name suggests) is eventually
formed the embryo or baby plant — the
essential part of the seed.
Immediately after fertilization endo-
$)>cr-m begins to form in the embryo sac,
either by cell division — as in some Dicoty-
ledons— or by free cell formation — as in
all Monocotyledons and many Dicoty-
ledons. The embryo sac meanwhile
increases greatly in. size and gradually
* Called also the germsphere and ovum.
FIG. 572. — SPINY FRUIT OF
MEGARRHIZA CALIFORNICA.
FIG. 573. — DANDELION (Taraxacum officinale).
The plumed fruits form a globe of down, which is broken by the wind and the separate fruits sail like parachutes
to a distance.
467
468
HUTCHINSON'S POPULAR BOTAXY
absorbs the tissue of the nucellus. In plants of the Water-lily and Pepper
orders (Nymphseacese and Piperacese) and a few others, a portion of the
nucellus remains, and forms what is known as perisperm. When both the
endosperm and perisperm are completely used up by the embryo in the course
of its development, the ripe seed consists simply of a seed-coat (formed from
the integuments of the ovule) and the embryo, and is described as ex-
albuminous. In cases where the ripe seed contains endosperm as well
as the embryo, it is called an albuminous seed. As we have already
dealt with the subject in Chapter VI, we need not retrace the ground here.
From what has been said, however, the distinction between a fruit and
a seed must be at once evident. The former is a ripened and developed
ovary ; the latter, an impregnated
and matured ovule. The fruit, in
fact, contains the seed or seeds,
just as the ovary contains the
ovule or ovules. In the Gymno-
sperms, which have naked ovules,
the seeds are of necessity naked
also ; hence they are not true
fruits. True fruits are, indeed,
confined to the Monocotyledons
and Dicotyledons.
In dealing with the diversi-
ties of form and external struc-
ture of fruits and seeds, it is
interesting to consider them in
the light of Adaptation. By this
means the inquiry is immensely
simplified: for it is evident that
those diversities are mainly di-
rected to one end — the dispersion
of the seed. The seed, in fact,
must be adapted to travel.
Now seeds and fruits were great travellers centuries before Vasco da
Gama and Columbus were heard of. and had crossed seas and continents,
and planted colonies all over the world long before the earliest caravan set
out from Bactria, or the first Phoenician merchantmen spread sail on the blue
waters of the Mediterranean. The necessity for becoming travellers was
imposed upon the vegetable community from the outset. Had those old-
world fruits just fallen from their parents' arms, so to speak, and lain where
they dropped, the consequences must have been disastrous. In a few years
vegetation would have been almost choked ; the strongest plants would have
killed out the weaker, whole families of plants would have thus become ex-
tinct, and the distribution of the remainder would have been much retarded.
FIG. 574. — WOOD-SORREL (Oxalis)
EXPELLING ITS SEEDS.
THE PROMISE OF- THE PLANT THAT IS TO BE 469
FIG. 575. — SEED OF WOOD-
SORREL.
The elastic outer integument is burst-
in? open to expel the seed.
It is therefore a matter for thankfulness that
provision has been made in nature for the dis-
persal of the fruits and seeds of plants. This
great end is effected in many ways. Sometimes
the plant ejects its own offspring in a more or less
forcible manner by means of special tissues which
act as slings, catapults, etc. : sometimes the fruits
themselves are capable of creeping or hopping
along the ground ; sometimes they are provided
with plumes, aeroplanes, or with envelopes filled
with air, which render them so buoyant that they
are able to perform long aerial journeys, the least breeze being sufficient
to carry them along : sometimes the wind lays hold of them when on the
ground and drives them forward with rapidity: sometimes the water is
their friend, and stream and torrent, lake and ocean, become instrumental
in transporting them to new and distant homes ; sometimes the fruits are
furnished with hooks or sticky secretions which facilitate their dispersion by
birds and other animals.
The Wood-sorrel \0xalis acetosella), whose delicate white blossoms may
be often seen peeping among the mossy uncovered roots of forest-trees, is
one of our commonest wild-flowers. It offers a familiar example of plants
with sling fruits. When the seeds are ready for dispersion, the capsules
containing them burst open, and the strong tense tissue which covers each
of the seeds being
ruptured at the same
time, the seed is
jerked out to a con-
siderable distance
(figs. 574, 575). In
the Squirting Cu-
cumber (Ecballium,
daterium. fig. 576 1
the arrangement is
even more curious.
The seeds are con-
tained in a juicy
pulp, which fills the
fleshy and bristly
•' cucumber," and
which is kept from
bursting out by the
hooked and stopper- ^ 576>_SQUIKTING CUCUMBER (Ecballium elaterium).
like Stalk. When when the froit is ripe it breaks off from the stalk, and from this point the seeda
the Seeds are ripe, and pulp are squirted out with force.
470
HUTCHINSON'S POPULAR BOTAXY
the fruit severs itself from the stalk, and instantlj- the seeds are squirted
out in a fountain of pulp through the unprotected hole. In the Touch-
me-not Balsam (Impatiens noli-me-tanyere, fig. 577 1 the five divisions of
the capsule leap from the stalk when the seeds are ripe, and, twisting
suddenly up, get rid of their offspring in a very summary manner.
The Common Dandelion (Taraxacum ojficinale, fig. 573) offers the most
familiar example of the dispersal of plumed fruits by means of the wind.
Each of its white downy balls, "the schoolboy's clock in every town," is
an aggregation of such fruits, waiting for the first breeze to scatter them.
The beauty of these tiny parachutes, and the gracefulness of their motion
as they float through the summer air, cannot be too greatly admired. The
Tillandsias, main' of which are epiphytes, have plumed fruits which are
specially adapted for
anchoring them to the
bark of old trees, where
they are able to ger-
minate immediately.
In Cirsium nemarale,
one of the Plume This-
tles, the fruits just
break awa}- from their
sessile plumes and fall
to the ground, when-
ever an obstacle is en-
countered in the course
of flight. Doubtless
the obstacle gives suf-
ficient promise of teiva
fir ma below to encour-
age them thus to slip
their parachutes and
risk a descent.
Creeping fruits are
characterized by their stiff bristles, which are peculiarlj- sensitive to mois-
ture. As a result of this sensitiveness, the fruits continually change their
position, and are able to propel themselves along in a definite direction, a
hygroscopic arrangement which enables them to be carried long distances.
Even jumping fruits are not unknown. Insect activity within the fruit
is the cause of the phenomenon, and one of its effects is undoubtedly the
dispersion of the seeds. Two plants are known which have so-called
•'jumping beans ''—viz., Sebastiania palmeri and S. bilocularis: and the
insects which cause the motion are Carpocapsa saltitans in the former,
and Grapkditita sebastiania in the latter. Sebastiania palmeri is a very
peculiar tree. It was discovered not many years since in a morass, half
FIG. 577. — TOUCH-ME-NOT BALSAM (Impatiens noli-me-tangere)
EXPELLING ITS SEEDS.
471
472 HUTCHINSON'S POPULAR BOTANY
a mile square, in the neighbourhood of Alamos, Mexico. The fruit is of
triangular shape, divided into three equal portions by strongly defined
lines. Two of these parts contain a small spherical black seed: the
third, a "jumper" or small maggot. On falling to the ground the fruit
splits, and that portion which contains the maggot immediately starts off,
hopping in an extraordinary manner away from the tree on which it grew.
The object of these movements has not yet been discovered, but the
theory is that the maggot instinctively knows that if it remains near
the parent tree it will be destroyed by an enemy. The insect lives upon
the contained seed, and has no desire to escape — indeed, seems to be
extremely comfortable in its dark quarters. If a small hole is carefully
bored in the shell, the maggot instantly sets to work to repair the damage,
and in a very short time will have closed the hole with a fine silky web.
After this is done the insect resumes its tireless and saltatory travels. As
FIG. 579. — STRAWBERRY (Fragaria vesca).
The first figure shows (a) ovary, (6) style, and (c) lobed stigma. The second figure is a section through the receptacle
(a) of an unripe " berry," with membranous pistils seated on the surface. The third figure shows the same in a ripe
condition with carpels on the exterior ; and the remaining figure is a section through one of the carpels, showing
the contained seed.
there is no hole or other indication of a way by which the shell could
be entered, it is supposed that the egg is laid in the flower before the
fruit is formed ; probably also, the moth which lays the egg cross-pollinates
the flower at the same time. The perfect insect is a grey-brown moth,
with speckled upper wings which measure three-quarters of an inch from
tip to tip. The moth releases itself from its prison by chiselling out a piece
of the hard shell, like a circular pavement-trap in miniature. The most
delicate fret-saw, even in skilled hands, could not do the work better.
It must be understood that these "jumping beans" never produce seedlings,
for the contained larva destroys the seed.
Instances are even known of whole plants which migrate from place
to place when their fruits are ripe. Of this sort are the wonderful " wind-
witches " of the Russian steppes, which have so appealed to the imagination
of the peasants of those regions. At the fruiting stage the stiff erect
THE PROMISE OF THE PLANT THAT IS TO BE 473
FIG. 580. — APPLE.
Longitudinal section of pome.
flowering stems of this plant, which spring
from a common axis almost level with the
root, curve outwards to the circumference
of the plants, and by that means give a
strong pull to the radish-shaped root,
sufficient to force it from the ground. The
environment of the plant favours this
singular and apparently suicidal proceed-
ing, for the earth during the summer season
is full of cracks. Then, when the wind
comes howling over the steppes, the plant
is caught up and driven along with others
of its kind, and together they fly bounding
over the plain. One by one their wild
careers are checked, and each settles down to shed its seeds in its new
resting-place.
Having offered these general remarks, we will now consider the subject
of the Phanerogamic Fruit in more detail.
A fruit or ripened ovary consists,
normally speaking, of two parts — the pro-
tective enveloping case, known as the
pericarp, and the seed or seeds (ripened
ovules). The pericarp consists of three
layers, each of which has a distinguishing
name. The outermost layer — i.e. the in-
tegument or skin of the fruit— is the epi-
carp ; the middle layer is the mesocarp ;
and the inner coat the endocarp. When, as frequently happens, the
middle layer is of a fleshy or succulent nature, it is called the surcocarp.
It was noticed a few pages back that
parts of plants are sometimes described as
fruits which are not true fruits at all. We
call these spurious fruits pseudocarps. The
strawberry, apple, fig, and mulberry are
familiar examples. The red, succulent,
fleshy part of the Strawberry is not a
ripened ovary, but the greatly swollen re-
ceptacle or thalamus of the flower ; and the
real fruits are the small, dry, seed-like
carpels scattered over its surface. In an
Apple the edible part is not the ovary
alone, but embraces the succulent and en-
larged floral receptacle, which also, as in
the Strawberry, forms the bulk of the
FIG. 581. — MULBERRY.
.V pseudo-sym'.irp.
FIG. 582. — MEDLAR.
A. pome.
474
HUTCHINSON'S POPULAR BOTANY
" fruit." The ovary occupies the cavity of this much-distended tube, and
is fused with the inner wall of it. The " pips " are the seeds. This form
of spurious fruit is termed a pome (fig. 580). The chief substance of a fig.
again, is its fleshy receptacle or axis, the true fruits being the hard yellow
grains borne on the inside of the cavity of the receptacle. In the Mul-
berry (Moms') the bracts of the clustering flowers coalesce with the peri-
anth, and form a succulent matrix for the individual fruits. A mulberry
is, in fact, a collection of spurious fruits fused together — in botanical
language, a pseudo-syncarp (fig. 581).
Other well-known examples of pseudo-syncarps are afforded by the
Bread-fruit-tree (Artocarpus incisa) and the Pineapple (Ananassa sativa).
These collective fruits, as they are called, must be carefully distinguished
from aggregate frtdts. in which the clustered carpels are derived from a
single flower, as in the Raspberry and Black-
berry (Rabus idceus and R. fruticosus). The
raspberry and blackberry, moreover, are syn-
carps, not pseudo-syncarps.
Thus we come to true fruits. These may be
conveniently divided into three classes. To the
first class belong those fruits which break and
shed their seeds, or are dehiscent ; to the second
class, those which do not break, or are inde-
hiscent ; and to the third class, those splitting
fruits which in some cases shed their seeds, and
in others — the majority of cases — do not. We
call these splitting fruits schizocarps.
Of the various forms of dehiscent fruits one
of the commonest is the capsule. Strictly speak-
ing, capsules are fruits with two or more carpels
whose pericarp liberates the seeds by toothed
or valvular openings, by pores, or by the falling off of a lid ; but the term
is frequently applied, with more latitude than correctness, to all dry de-
hiscent fruits. However, as the other forms of capsule have special distin-
guishing names, we shall here employ the term in its more exclusive sense.
Good examples of porous capsules are found in the Poppy (Papaver}.
The pores are provided with little flaps on the sides, beneath the eaves
of a roof-like top, and these flaps move up and close the pores in time
of rain, or when the atmosphere is exceptionally moist. In dry weather
they open outwards, and as the poppy-heads sway in the breeze the light
small seeds get shaken out and scattered over a wide area.
Protective arrangements somewhat similar to the above seem to be
a special feature in what are known as toothed capsules. The Corn-cockle
(Lychnis githago, fig. 583) is a case in point. In wet weather its five teeth
meet in a point and prevent the entrance of a drop of rain but on dry
FIG. 583. — CORN-COCKLE.
Toothed capsule— open an 1 close.1.
Photo hi/]
FIG. 584. — MEDLAR (Mespilus germanica).
The fruit ys a pome like that of the Apple, consisting of the ovary and swollen receptacle, crowned by t.
lobes whi-h surround a demised area. The tree, which is a native of Greece Asia Minor and I • .-. . , h
naturalized in the he 1-erows of the Midlands and South of England, also m the Channel Inlands.
[/?. Step.
476
HUTCHINSON'S POPULAR BOTANY
days, and when the seeds are ripe, the teeth are curved back. The seeds
escape by this opening.
Compare carefully the capsules depicted in figs. 586, 587, which are shown
in transverse section, and represent respectively the fruit of the Iris and
Meadow-saffron (Colchicum autumnale) : fig. 585 is a fruit of the Common
Thorn-apple (Datura stramonium). In fig. 588 the three forms are
shown diagrammatically. Now, in each of these examples it will be noticed
that the capsule dehisces in a different manner. In the Iris the capsule
splits through the back of its three seed-containing cavities (by its dorsal
suture, as we should say), and thus the cavities or loculi are broken open
This is known as loculicidal dehiscence. Sep-
ticidal dehiscence is illustrated in the
Meadow-saffron. Here the carpel separates
into its component ovaries, each of the walls
of separation or dissepiments dividing into
two, and thus the loculi remain intact. In
the Thorn-apple there is no splitting of the
dissepiments, which remain attached to the
axis, but the carpellary wall which surrounds
them, and to which they are attached, breaks
away at the three points of attachment, and
so the seeds escape. This is septifragal de-
hiscence.
From the circumstance that, in each of
the three examples here given, the pericarp
comes away in pieces or valves, the dehis-
cence is also said to be valvular. Allusion
has been made already to two very remark-
able instances of valvular dehiscence. The
sling-fruits both of Jmpatiens and of Oxalis
come under this category. In the former,
the mesocarp consists of large and highly
turgid cells, which keep the whole of the capsule in a state of great tension ;
so that when the fruit is touched the valves rly open, and eject the seeds
with considerable force ; in the latter, as we have seen, the bursting of the
elastic fieshy outer integuments of the seeds is the cause of their expulsion.
" On the heights of the Kahlenberg, at Vienna, at the edge of the wood,''
says Kermer, grows an under-shrub which bears the name of Dorycnium
herbaceum. It is one of the Papilionacese, and develops spherical one-seeded
fruits, which ripen in October. I once collected from this plant several
twigs laden with fruit, for the purpose of a comparative investigation on
which I was engaged, and brought them home and laid them on my writing-
table. Next day as I sat reading near the table, one of the seeds of the
Dorycnium was suddenly jerked with great violence into my face. Shortly
FIG. 585. — THORN-APPLE (Datura).
The carpellary wall alone splits and separates
from the dissepiments. Septifra.sal dehiscence.
THE PROMISE OF THE PLANT THAT IS TO BE 477
FIG. 586. — IRIS.
e section of capsule,
loculicidal deliiscenc
afterwards I saw a second, third, fourth, and
ultimately about fifty seeds let fly from the
small clusters of fruit, and each time I heard
a peculiar sound which accompanied the
bursting open of the fruits and ejection of
the seeds. The rays of sunshine from the
window had evidently heated and dried the
fruits, and occasioned this .surprising phe-
nomenon." The poet Goethe gives a some-
what similar account of the seed dispersion
of Acanthus mollis ; and methods closely re-
sembling these have been observed in many
other plants. Plants with sling-fruits form,
in fact, a large group.
A very curious form of capsule is the
pyxis, ia which the splitting takes place
transversely, and the top of the capsule falls
completely off. The fruits of Anagallis, the
Pimpernel family (fig. 589). all have this mode
of dehiscence ; but more striking examples
are furnished by the less known tropical genus, Lecythis, about which many
a quaint story is told. Lecythos means an oil-jar, and the popular name
for these fruits is " monkey-pots." '•'• The great urn-shaped fruits," writes
Charles Kingsley, " big enough to serve for drinking-vessels. each kindly
provided with a round wooden cover, which
becomes loose, and lets out the savoury
*apucaia nuts inside, to the comfort of all our
' poor relations.' The pots are used for catch-
ing monkeys." "Filled with sugar," says a
writer in the Gardeners Chronicle (1861),
•; they are placed on the ground which such
animals frequent. The sugar attracts the
latter, who pick it out leisurely till they are
disturbed, when they insert the paw. grasp
as much sugar as it will hold, and endeavour
to escape with the prize. But their doubled
fist, being larger than the mouth of the pot,
cannot be withdrawn, and the monkeys,
tenaciously holding the sugar, run off with
a pot firmly enclosing one paw. This ren-
ders it impossible for them to escape from
their pursuers by climbing, and they are
easily run down."
The remaining dry dehiscent fruits which
FIG. 587. — MEADOW-SAFFRON.
L'ransver-:e section, illustrating septicidal
deli licence.
478
HUTCHINSON'S POPULAR BOTANY
FIGS. 586, 587, AND 585.
are sometimes described as capsules are the follicle, the legume, the siliqua,
and the silicula. We will take them in that order.
The follicle is a superior, one-celled fruit, containing one or more seeds.
which are liberated in most instances by a ventral suture only. Magnolia
glauca and some other species of Magnolia are exceptions. As a rule,
several follicles are collected in a cluster at the end of a flower-stalk, but
solitary follicles are common in Proteacese; and there are a few plants
(e.g. the Pseony, normally developing two or more follicles with each flower,
which occasionally produce but one. The Columbine (Aquilegia) and Lark-
spur (Delphinium) offer good examples of the follicle.
The legume or pod resembles the follicle in that it arises from a single
carpel ; but, unlike the follicle, it dehisces at both sutures. This is the
characteristic fruit of the great order Leguminosece, to which the Pea
and Bean belong. The legumes assume a curious twisted form in the
small genus Scorpiurus, which includes the interesting Caterpillar-plant
(8. vermiculata, fig. 594), and a spiral form in the Purple Lucerne (Medicago
sativa, fig. 597). When the pod is contracted in a bead-like (moniliform
manner, as in the Gum Arabic plant (Acacia arabica, fig. 601), it is termed
a lomentum.
The legumes of the Earth-nut (Arachis
hypogcea, fig. 599) deserve notice on account of
peculiarities other than those of form. The
specific name hypogcea (Greek upo ge, under
ground) is an allusion to the curious circum-
stance that the young pods, as they begin to
mature, are forced into the earth by a lengthen-
ing of the flower-stalks, and ripen their seeds
-^^_r_ ^ below the ground. This phenomenon is not
\ confined to the Earth-nut, but has been ob-
served in a few other plants — Trifolium subter-
raneum, for example, and the Sweet Violet
(Viola odorata). The fruits of the latter are
completely," like a iid. not leguminous. Plants with burying fruits,
FIG. 589. — PIMPERNEL.
The fruit is a pyxidium, which splits trans-
versely and the upper part falls away
Photo fcy]
FIG. 590. — HOUSE-CHESTNUT (dls-ulus hippocastanum).
» <,„„„„. „„*•. capsule, and when ripe it splits into two or three valves to set free the large seeds
era. Mountain regions of GREECE, PERSIA, and NORTHEKN INDIA.
479
The prickly fruit is a FU
known as Conkers. Mountain reg
480
HUTCHINSON'S POPULAR BOTANY
.says Kerner, " have always been a source of wonder to botanists, and their
number is not large. The best known examples are Arachis hypogcea.
Cardamine chenopodiifolia. Linaria cymbalaria, Phrynium micans, Trifolium
fiubterraneum, and Vicia amphicarpa. If these plants were only to bring
fruit to maturity underground, or were to draw all their fruits below the
ground as soon as the seeds were mature, in order that germination and the
development of new plants might ensue at that spot, their behaviour
would imply a renunciation of dispersion to any distance, and the phe-
nomenon would be highly enigmatic. The puzzle is satisfactorily solved,
however, when we take into account the fact that all these plants in-
variably have the chance of being dispersed to great distances either
before the fruits become concealed in the earth, or by means of a second
form of fruit which ripens aboveground, and is evidently adapted to being
scattered abroad through the agency of animals, or by means of aerial or
Photo by]
[E. Step.
>lletia excelsa).
The hard-shelled triangular nuts to the number of fifteen or twenty are enclosed in a thick-walled, woody fruit which
oan only be broken by crreat force. The seeds (" nuts ") are released naturally by the rotting of this strong-bos.
FIG. 591. — BRAZIL NUT (Bertholletia ezcelsa).
SPECKLED ODONTOGLOT fOdontoglouun n
others con-
tend for
their animal
nature. Pro-
duced from
microscopic
spores, they
emerge as a
kind of Am-
oeba (swarm-
cells) that
glide with a
[E. step. streamin g
FIG. 717. — Mucilago spongiosa. .
One of the Myxomycetes that may be found in pastures climbing up the stems of grasses 7
and weeds to form its aethalia. thrusting
HIDDEN MARRIAGES
569
•Photo by]
FIG. 718.— Trie hia varia.
decaying wood. The densely packed sporangia of ochreous tint are shown slightly enlarged.
IE. Step.
out a whip-like process on the advancing side, surrounding Bacteria and
other minute organisms and feeding upon them, chiefly in decaying wood
and other vegetable matter. At a certain period of their life many of
these come together and unite into a plasmodium, a creamy mass of naked
protoplasm, which afterwards divides and forms sporangia, enclosing
numerous dust-like spores like those by which the swarm-cells were
originally produced. These sporangia differ greatly in form and size, each
genus having its characteristic form and the species differing from each
other in minor points, some becoming combined in cake-like or cushion-
like masses of relatively large size, others forming small spherical or
cylindrical bodies, stalked or sessile.
Each swarm-cell possesses a single nucleus and a contractile vacuole.
From the rear end it puts out finger-like processes (pseudopodia) with which
it catches its food. The pseudopodia draw it into the body, where it is
digested in the vacuoles. The swarm-cells increase in numbers by- each
dividing into two, and these dividing in the same manner again and again.
When they unite into the creamy mass known as the plasmodium, they
alternately advance and recede as a whole, but the movement is always
more in one direction than the other. After a few hours the plasmodium
570
HIDDEN MABKIAGES 671
breaks up into few or many (according to species) smaller masses which
form into sporangia. A crust forms around the sporangium and the enclosed
portion breaks up into spores ; but prior to this a system of delicate threads
is constructed, forming a network in which the spores are held. This is
known as the capillitium. There are also in some species free threads called
elaters, spirally twisted and hygroscopic. As the sporangium ripens and
dries, the investing membrane breaks up by shrinking and the spores are
only held together by the capillitium network. The elaters expand and
contract, their movements throwing the spores out through the meshes
of the capillitium. Many of them have granules of calcium carbonate
in the walls of the sporangia and as knots on the capillitium threads. The
same substance appears in the plasmodium.
The period of nutrition corresponds with the amoeboid state — that is, the
swarm-cell and the plasmodium. As swarm-cells they are negatively helio-
tropic — they avoid
the light and retire
into the darkness
of rotten wood and
decaying leaves;
but in the plasmo-
dium stage their
heliotropism be-
comes positive —
they stream out to-
wards the light in
order to form their FIG. 720. — DEVELOPMENT OF A MYXOMYCETE.
SDOranfia On the •I-ne uPPer row shows : 1, a spore ; 2, the contents of the same emerging as a swarm-cell
& with a nucleus ; 3, the same with nucleus, vacuole, and llagellum ; 4, the swarm-cell
exterior Of their has assumeci tne amoeba form. Below is a portion of plasmodium, and to the right
a sporange. All diagrammatic.
habitat. The
swarm-cells are also positively hydrotropic— they move from dry to moist
places; and both swarm-cells and plasmodium are trophotropic — they move
towards nutrient substances.
De Bary, to whose researches much of our knowledge of the Class is due,
decided in favour of their animal nature on account of the formation of a
plasmodium by the aggregation of the swarm-cells. But although he said
their place was " outside the limits of the vegetable kingdom," he continued
to include them in his botanical works. What has always appeared to
us a strong argument against their being driven out of the vegetable
kingdom is that their exhibition of animal traits is restricted to their
earlier stages of development. The test of their real nature should be
applied to their ultimate condition and their mode of reproduction, both
of which are essentially vegetable. The catching and digesting of Bacteria
is indicative of animal nature, it is true, but what about the trapping and
digesting of animal food by the Sundews, the Butterworts, Bladderworts,
572 HUTCHINSON'S POPULAR BOTANY
and Pitcher-plants ? The power of movement in the swarm-cells is
paralleled by similar movements in the antherozoids of many cryptogams :
and the development of cellulose is by no means a common feature among
animals.
But however one may regard these Mycetozoa or Myxogastres, they
remain an exceedingly interesting group, such as may be studied easily
by all who walk in the woods and country lanes, and we shall try by
a few examples of different types to give some elementary idea of their
beauty and diversity of form, and colour, such as may be acquired by
a pocket lens — though for their serious and exact study the microscope is
required to be brought into use, as the determination is largely based upon
the character of the capillitium, the size and colour of the spores, and
so forth.
One of the largest of known species is Brefeldia maxima, of which we
have already (fig. 186) given a photograph showing it in the plasmodium
stage. The appearance of this plasmodium to one who only knows the
" Myxies " as almost microscopic forms is astonishing. We have seen it
issuing from a large pine stump, flowing out over the bark and climbing
up the stems of plants at a short distance in sheets that would cover several
square feet. There were no visible cavities in the stump — to all appearance
the wood was sound. But they issued as microscopic swarm-spores from
microscopic cavities, and multiplied by division on the exterior. A small
portion of such an outflow is shown in the photograph of the natural
size (see p. 149). After a time the creamy whiteness gets a pinkish tinge,
then brown, and a crust forms over detached oval portions two or three
inches long. The crust is somewhat shiny, of a dark brown colour, and
with an indistinct tesselated appearance. This is an eethalium or compound
sporangium, and the tesselated appearance is due to the fact that there
are a large number of sporangia packed closely side by side. The semi-
fluid creamy mass inside becomes a dry, fine powder like soot. The crust
contracts, splits and flakes off, leaving the spores (for such is the powder)
free to be blown out by the air-currents (fig. 719).
Mucilago spongiosa, shown in fig. 717, also forms an sethalium, but it is
quite different in appearance from that of Brefeldia, the sporangia com-
posing it being more loosely compacted. Its creamy plasmodium may be
seen in autumn creeping up the stems of grasses and weeds in pastures. At
some distance up the stalks it consolidates into masses such as are shown
in the photograph, which are thickly covered on the exterior with crystals
of lime. Its spiny spores are dull purple in colour. Leocarpus fragilis may
frequently be found on pine stumps, with large, polished, brown sporangia,
clustered owing to the weakness and shortness of their stalks. Our photo
(fig. 721) represents it in the plasmodium stage creeping among moss and
pine-needles on a pine stump.
The capillitium of some species expands to a remarkable size when the
HIDDEN MARRIAGES
573
sporangia dehisces. This is particularly the case with several species of
Arcyria. In Arcyria nukans, for an extreme example, the capillitium
extends to about ten times the length of the sporangia from which it
escaped. Trichia botrytis in the swarm-cell stage lives in wood that is
thoroughly rotten and sodden, coming to the exterior to form a purple-
brown plasmodium, and finally the massive-stalked pear-shaped sporangia.
These are at first of a beautiful red colour; but as they dry and harden
Photo by]
FIG. 721. — Leocarpus jragilis.
The plasmodium of this Myxomycete creeping over mosses and pine-needles on a pine stump.
there is some reduction in the thickness of the stalks and the sporangia
turn to yellowish-olive, red-brown, or purple-black. In some cases each
sporangium stands apart on its own stalk, but in others from three to eight
stalks will unite and support a cluster of as many sporangia.
GLOSSARY OF TERMS
[.Vote-As the application of these ter
been fully explained in the text, the repetition of the same here has been
considered unnecessary.]
Achene ; Gr. «, not, and chaino, 1 open
Acicular ; Lat. acicula, a small needle
Actinomorphic ; Gr. aktis, a ray, and morphe, a
shape
^Estivation ; Lat. (estas, summer
^Ethalium ; Gr. aithalox, soot
Aleurone ; Gr. aleuron, ground wheat
Allogamy ; Gr. allo*, other, and gamos, marriage
Amentum ; Lat. a thong
Amplexicaul ; Lat. arnplcxus, embracing, and caulis,
stem
Anatropous ; Gr. anatrepo, to turn in or over
Andrcecium ; Gr. andros, a male, and oikos, a
Anernophilfe ; Gr. anemox, the wind, and phileo, to
love
Angiosperm ; Gr. aygeion, a vessel, and sperma,
seed
Annular; Lat. annulus, a ring
Annulated ; Lat. annutatus, ringed
Annulus ; Lat. a ring
Antherid ; Gr. anthems, flowerv, and id ion, a diminu-
tive suffix
Antherozoid ; Gr. antheros, and zoon, an animal
Anthers ; Gr. antheros.
Anthocyanin ; Gr. anthos, flower, zndkuaneos, dark
blue
Antipodal ; Gr. anti, opposite, and pous, foot
Apocarix)us ; Gr. apo, separate, and karpoi, fruit
Apogamy ; Gr. apo, and gamos, marriage
Archegone ; Gr. a re he, a beginning, and gone, birth,
production
Archespore ; Gr. arche, and sporos, seed
Ascidiform ; Gr. askidion, a little bottle
Auriculate ; Lat. auricula, an ear
Autogamy ; Gr. auto*, self, and gamos, marriage
Bract, Bracteate; Lat. bractea, a thin plate of
metal
Caducous ; Lat. cado, I fall
Calceolate ; Lat. calceolus, a slipper
Calypter ; Gr. calyptra, a covering or veil
Calyx ; Lac. calix, a cup
Cambium : Lat. cambio, I exchange
Campanulate ; Ital. yampana, a bell
Campylotropoua ; Gr. campulus, curved
Capillitium ; I,at. enpillut, a bush of hair, or beard
Capitulum ; Lat. a little head
Carpel ; Gr. karpos, fruit
Carposperm ; Gr. karpos, and sperma, seed
Caryophyllaceous ; Gr. kantophullon, the clove-tree
Caryopsis ; Gr. kartion, a nut, and opsis, appearance
Cauline ; Lat. caulis, a stem
Chlorophyll; Gr. chlorog, green, and phullon, a
leaf
Circinate ; Lat. circinatus, rounded
Cladode ; Gr. klados, a branch
Cleistogamic ; Gr. kleistos, closed, and gamos,
marriage
Coleorhiza ; Gr. kofeos, a sheath, and rhiza, root
Collenchyma ; Gr. kolla, glue, and enchuma, some-
thing poured in
Columel ; Lat. cohuiiella, a little column
Conduplicate ; Lat. conduplicatus, doubled
Connate ; Lat. con, together, and natus, born
Convolute ; Lat. conroli'tus, rolled up
Cordate ; Lat. cor, the heart
Corm ; Gr. kormos, a stem or trunk
Corniophyte ; Gr. kormos, and phuton, a plant
Corolla ; Lat. diminutive of corona, a crown
Cotyledon ; Gr. kotuledon, a cup-shaped cavity
Creniocarp; Gr. kremannitmi, to hang, and karpos,
fruit
Crenate ; Lat. crena, a notch
Cruciform ; Lat. crux, a cross, and forma, form
Cryptogam ; Gr. kruptos, hidden, and gamos,
marriage
Cucullate : Lat. cucullus, a hood or cowl
Cuneate ; Lat. cuneus, a wedge
Cyanic ; Gr. kitaneos, dark blue
Cyanophyll ; Gr. kuaneos, and phullon, leaf
Cystoliths ; Gr. kustis, a bag or bladder, and lithof,
a stone
Deciduous ; decidere, to fall
Decurrent ; Lat. de, down, and curro, to run
Decussate ; Lat. dccitsso, to divide crosswise
Dehisce ; Lat. dehiscere, to gape
Dentate ; Lat. dens, a tooth
Dichogamy ; Gr. dicha, in two parts, and gamos,
marriage
I 'ichotomous ; Gr. dicha, and tome, to cut
Digitato ; Lat. digitus, a finger
Dioecious ; Gr. di, two, and oiko*, a house
Distichous ; Gr rfi, and stichos, a row
Elater ; Gr. an impeller
Emarginate ; Lat. e, privative, and margo, a
margin
Endocarp ; Gr. endon, within, and ka rpot, fruit
Endosmose ; Gr. endon, and osmos, impulsion
Endosperm ; Gr. endon, and sperma, seed
Endospore ; Gr. endon, and sporos, seed
Entomophilae ; Gr. entoma, insects, and phileo, to
love
Epicarp ; Gr. epi, upon, and karpos, fruit
Epidermis ; Gr. epi, and derma, skin
Epiphyllous ; Gr. epi, and phullon, a leaf
Epispore ; Gr. epi, and sporos, seed
Exosmose ; Gr. cxo, outside, and osmos, im-
pulsion
o74
GLOSSARY OF TERMS
575
Exospore ; Gr. exo, and sporos, seed
Extrorse ; Lat. e.ctrorsum, outwards
Fascicular ; Lat. fasciculus, a small bundle
Filament ; Lat. Mum, a thread
Filiform ; Lat. Jilum, and formn, form
Fistular ; Lat. .fistula, a pipe
Flagellum ; L;it .flagella, a little whip
Fusiform ; Lat. fusus, a spindle, undform-i, form
Galeate ; Lat. gnlea, a helmet
Gamete ; Gr. wife or husband
Gamopetalous ; Gr. gamos, marriage, and petal.
Applied to corolla.
Gamosepalous ; Gr. gainos, and sepal. Applied to
calyx
Gibbous ; Lat. cfibbosux, humped
Glume ; Lat. gluma, a husk
Gluten ; Lat. paste
Gymnosperm ; Gr. gumnos, naked, and sperma,
seed
Gymiiostomous ; Gr. gumnos, and stomn, a mouth
Gynoacium ; Gr, gune, a female, and oikos, a house
Gynandrous ; Gr. gune, and andros, a male
Hastate ; Lat. hasta, a spear
Heterophyllous ; Gr. heteros, different, and phullon,
a leaf
Heterostylism ; Gr. heteros, and style
Hilum ; Lat. a very small thing
Hydro philae; Gr. udor, water, and phileo, to love
Hypocrateriform ; Gr. hvpo, under, and kratcr, a
goblet
Indusinm ; Lat. an under-garment
Inflorescence ; a collective name for all the flowers
produced on one floral shoot
Infundibuliforrn ; Lat. infundibulum, a funnel
Introrse ; Lat. introrsum, inwards
Involucre ; Lat. involucrum, a wrapper
Involute ; Lat. involutus, wrapped up
Labiate ; Lat. labium, a lip
Laciniated ; Lat. lacinia, a fringe or border
Latex ; Lat. juice
Legumin ; Lat. pulse
Leukoplasts ; Gr. leukos, white, and plasaui, that
which has been formed
Loculicidal ; Lat. loctdnx, a little place, and ca'do,
to cut.
Malacophilte ; Gr. malakoa, soft [mollusc], and
phiieci, to love
Manubrium ; Lat. a handle
Medullary ; Lat. medulla, the marrow
Megaspore ; Gr. mega, great, and sporos, seed
Meristem ; Gr. meristos, divided
Mesocarp ; Gr. meson, middle, and karpos, fruit
Metabolism ; Gr. mctabole, a changing
Micropyle ; Gr. mikros, little, and pule, A gate
Microspore ; Gr. mikros, and sporos, seed
Monadelphous ; Gr. monos, sole, and adelphos,
brother
Moniliform ; Lat. monila, a necklace
Monoecious ; Gr. monos, one, and oikos, a house
Mucronate ; Lat. mucro, a sharp point
Multicellular ; made up of many cells
Mycele ; Gr. mukos, mushroom, and kele, a
tumour
Napiform ; Lat. napus, a turnip, and forma,
form
Nodulose ; Lat. nodus, a knot
Nueellus ; Lat. nucula, a small nut
Nucleus ; Lat. mix, a nut or kernel
Obcordate ; Lat. ob, inversely, and cor, the heart
Ooovate ; Lat. ob, and oratus, egg-shaped
Oophyte ; Gr. oon, an egg; and phuton, a plant
Oosperm ; Gr. oon, and sperma, seed
Oosphere ; Gr. oon, and sphaira, a sphere
Orbicular ; Lat. orbicu/us, a small disc
Ornithophihe ; Gr. ornithos, a bird, and phileo, to
love
Orthotropous ; Gr. orthos, straight
Ostiolum ; Lat. diminutive of ostium, a door
Ovary, Ovule ; Lat. ovum, an egg
Pales ; Lat. palea, chaff
Palmate ; Lat. palma, the palm of the hand
Panicle ; Lat. pavicula, cat's-tail
Papilionaceous ; Lat. papilio, a butterfly
Pappus ; Gr. pappos, the down of plants
Paraphyse ; Gr. paraphus, growing beside
Parenchyma ; Gr. parenchuma, the spongy sub-
stance of the lungs
Pari pinnate ; Lat. par, equal, and pinnatus,
feathered
Pedate ; Lat. pedatus, from pes, foot
Pedicel, pedicillate, peduncle; Lat. diminutives of
pes, pedis, the foot
Peloria ; Gr. peloron, a monster
Peltate; Lat. pelta, a shield
Perfoliate ; Lat. per, through, &nd folium, a leaf
Perianth ; Gr. peri, about, and anthos, a flower
Pericarp ; Gr. peri, and karpos, fruit
Perichsete ; Gr. peri, and chaite, flowing hair
Peridium ; Gr. peri, and idea, form
Peri gone ; Gr. peri, and gone, womb
Perisperm ; Gr. peri, and sperma, seed
Peristome ; Gr. peri, and stoma, a mouth
Personate ; Lat. personatus, masked
Petal ; Fr. pttale, a leaf, used in reference to floral
leaves only
Phanerogam ; Gr. phaneros, evident, and gamos,
marriage
Phloem ; Gr. phloios, inner bark
Phyco-erythriii ; Gr. plmkox, sea-weed, and erythros,
red
Phylloclades ; Gr. phullon, a leaf, and klados, a
branch
Phyllode ; Gr. phullon, and i-idox, likeness
Phyllotaxy ; Gr. phullon, and tavis, order
Phylloxanthm ; Gr. phullon, and xanthos, yellow
Pileorhiza ; Gr. pileus, a cap, and rhiza, root
Pileus ; Gr. a cap or helmet
Pinnatifid ; Lat. pinnatus, feathered, and findo,
I split
Pinnatisect ; Lat. pinnatus, and seco, I cut
Pistil ; Lat. pixt ilium, a pestle
Plasoiodium ; Gr. plasma, anything moulded
Plicate; Lat. plica, a fold
Plumule ; Lat. pluma, a feather
Pollen ; Lat. fine flour or dust
Polyadelphous; Gr. polus, many, and adelphos,
brothe-a
Primine ; Lat. primvx, first
Procarp ; Gr. protox, first, and karpos, fruit
Prosenchyma; Gr. pros, beside, and enehuma,
something poured in
Proteus ; a fabulous person who could change
form at will
Protandrous ; 'Gr. proteros, before, and andros,
male
Protogynous ; Gr. protcros, and gune, female
Prothallium ; Gr. protcros, and thallos, a shoot
576
GLOSSARY OF TERMS
Protoneme; Gr. protos, first, and nema, a thing
spun, a thread
Protophyte ; Gr. protos, and phuton, a plant
Protoplasm ; Gr. protos, and plasma, that which
has been formed
Pseudocarp ; Gr. pseudos, false, and karpos, fruit
Pseudopodia ; Gr. pseudos, and podos, foot
Pulvinus ; Lat. a cushion
Pyxis; Gr. puxidion, a little box
Rachis ; Gr. the spine
Radicle ; Lat. radix, a root
Raphides ; Gr. raphis, a needle
Reniform ; Lat. ren, a kidney, and forma, form
Replum ; Lat. replum, the leaf of a door
Reticulated ; Lat. reticulum, a small net
Retuse ; Lat. re, back, and tundo, I hammer
Revolute ; Lat. revolutus, rolled back
Rostellum ; Lat. diminutive of rostrum, a beak
Runcinate ; Lat. runcina, a saw
Saccate ; Lat. saccus, a bag
Sagittate ; Lat. sagitta, an arrow
Saprophyte ; Gr. sapros, rotten, and phuton, a
plant
Sarcocarp ; Gr sarkos, flesh, and karpos, fruit
Scalariform ; Lat. scala, a ladder
Scape ; Lat. sea pus, a stalk
Schizocarp ; Gr. schizo, to split, and karpos, fruit
Sclerenchyma ; Gr. skleros, hard, and enchuma,
anything poured or put in
Secundine ; Lat. secundce, second
Sepal ; Fr. sepale, invented term to correspond with
petale
Septicidal ; Lat. septum, an enclosure, and ccedo,
to cut
Septifragal ; Lat. septum, and frango, to break
Sessile ; Lat. sessilis, sitting
Sorus ; Gr. soros, a heap
Spadix ; Lat. a palm-branch
Spathe ; Gr. spathe, a broad blade
Spathulate ; Lat. spathula, a broad slice
Spermocarp ; Gr. spcrma, seed, and karpos, fruit
Sporange ; Gr. sporos, seed, and aggeion, a vessel
Spore ; Gr. spora, seed
Sporocarp ; Gr. sporos, and karpos, fruit
Sporogenous ; Gr. sporos, and genao, to produce
Sporophyll ; Gr. sporos, and phullon, a leaf
Sporophyte ; Gr. sporos, and phuton, a plant
Stamen ; Lat. a fibre
Stigma ; Gr. stiff me, a point
Stomate ; Gr. stoma, a mouth
Style ; Lat. stylus, a stake
Subulate ; Lat. subula, an awl
Synantherous ; Gr. sun, together, and anther
Syncarpous ; Gr. sun, and karpos, fruit
Synergidae ; Gr. sun, and ergon, work
Testicular ; Lat. test is, a testicle
Tetraspore ; Gr. tetra, four, and sporos, seed
Thallophyte ; Gr. thallos, a shoot, and phuton, a
plant
Tomentose ; Lat. tomentum, down
Trichogyne ; Gr. trichos, hair, and yune, female
Truncate ; Lat. trunco to maim or cut off
Urceolate ; Lat. urceus, a pitcher
Utricuiar ; Lat. utriculus, a little bottle
Vernation ; Lat. rer, the spring
Versatile ; Lat. i-ersatilis, revolving
Verticillate ; Lat. verticillis, a little whorl
Xanthic ; Gr. ranthos, yellow
Xylem ; Gr. xulon, wood or timber
Zoophilae ; Gr. zoon, animal, and phileo, to love
Zoospore ; Gr. zoon, an animal, and sporos, seed
Zygote, Zygomorphic ; Gr. zeugnumi, I join, and
morphe, a shape
ERRATA
Page 49 — By the turning of a numeral in printing, the chemical formula for Glucose is made to read
C6H12O9 ; it should be C6H,2O6, as correctly given on page 44.
Plate III— Glory Pea (Clianthus dampieri). The popular name belongs to the New Zealand species
(€'. puniceus) ; we are informed that it is not used in connection with the Australian species.
Page 445 — Fig. 549 should, strictly speaking, be named Sntezeicort Yarrow, to distinguish it from Achillea
millefolium, the Milfoil Yarrow.
INDEX
Pages i-viii and 1-288 will be found in Vol. I. ; pages 289-576 in Vol. II.
(Scientific names of plants printed in italics.)
Abies canadensis, 66
Abnormal flowers, 324, 325
Absorption, 96
Abutilon, 445
Acacia, 232, 256, 280, 417,
478, 485
Acanthus, 302, 477
Accrescent calyx, 337
Acer, 49, 178, 180, 198, 270,
493
Aceras, 433
Achillea, 445
Achene, 488
Achlya, 537
Acicular leaf, 273
Acid sap, 98
Aconitum, 180, 253, 260, 336
Acotyledons, 172
Actcea, 261
Actinomorphic flowers, 340
Acuminate apex, 274
Acute apex, 274
Adansonia, 181
Adder's-tongue Fern, 509
Adhesion, 333
Adnate anther, 356
Adonis, 394
Adventitious buds, 148
Adventitious roots, 168, 188
Mcidium, 550
^Esculus, 66, 175, 245-247,
257, 479, 482
^Estivation, 329
./Ethalium, 572
Agapanthus, 395
Agaricinese, 542
Agaricus, 149
Agarum, 286
Aggregate fruits, 474
Agrimonia, 484
Agrimony, 484
Agrostemma, 45, 269
Ate, 350
Alaria, 558, 560
Albuminous seed, 170, 468
Alder, 415
Aldrovanda, 122
Aleurone grains, 53, 57, 85,
134, 146, 166, 556
11—19
Algse, red, 146, 556 ; brown,
560 ; green, 561 ; con-
jugate, 564
Allium, 61, 288
Allogamy, 334
Almond, 64
Alnus, 415
Alocasia, 443, 444
Aloe, 65
Alpine Liane, 335, 336, 412
Alpine Mad wort, 289, 295
Alternate leaves, 270
Alternation of generations,
390
Althaea, 329
Alyssum, 289
Amanita, 536, 542, 544
American Laurel, vii
Amoeba, 8, 9
Amorphophallus, 316, 393
Ampelopsis, 401
Amplexicaul leaf, 262
Anacardiacese, 66
Anagallis, 270, 274, 477
Ananassa, 474
Anastatica, 485
Anatropous ovule, 464
Andreacese, 392
Androecium, 354
Andropogon, 64, 142
Androsace, 341
Anemone, 316, 414, 417
Anemophilse, 448
Angiosperms, 89
Animal and plant mimicry,
2-6
Annual plants, 218
Annual rings, 211
Annular cells, 36
Annulus, 506
Anther, 321
Antheridium, 164, 166, 505
Antherids, 500, 554, 557
Anthers : adnate, 356 ; basi-
fixed, 356 ; dorsifixed, 356 ;
extrorse, 356 ; forms of,
354 ; innate, 356 ; in-
trorse, 356 ; sessile, 356 ;
versatile, 354
577
Antherozoid, 506, 510, 554
Anthocyanin, 282
Anthodium, 318
Anthornis, 446
Anthoxanthum, 262, 264
Anthurium, 399
Anthyllis, 254
Antiaris, 54
Antipodal cells, 466
Antirrhinum, 318, 322, 329,
362
Ants and Milk-sap of Let-
tuce, 46
Apocarpous pistils, 333
Apocynum, 364
Apogamy, 506
Apospory, 505
Apple, 337, 357, 473
Aquatic plants, 281
Aquilegia, 345, 348, 478
Arachis, 58, 478, 484
Aralia, 386, 393
Araucaria, 88
Araujia, 432
Archangel, 327
Archegone, 500, 510
Archegonium, 164, 166, 505
Archespore, 504
Arcyria, 573
Aretia, 341
Argemone, 378
Arillus, 496
Aristolochia, v, 268, 356, 374,
384, 404, 424
Armillaria mellea, 144, 145
Aroids, 136, 286
Aromatic oils, 62, 65
Arrow-grass, 461
Arrow-head, 268, 270, 275,
369
Artemisia, 186
Artillery-plant, 460
Artocarpus, 39, 45, 474
Arum, 42, 45, 131, 136, 140,
172, 313, 316, 317, 394,
400, 425
Asarum, 403
Asci, 548
Ascidiform leaf, 279
578
INDEX
Asclepias, 408
Ascomycetes, 537, 548
Ash, 254, 368, 369
Ash-leaved Seaweed, 559
Aspen, 64, 300, 448
Asperula, 221, 227
Aspidistra, 376, 385
Aspidium, 505
Asplenium, 246, 249, 500,
505, 511
Assimilation, 130
Astragalus, 56
Athyrium, 71, 167, 505
Atragene, 336, 412
Attar of Roses, 64
Auriculate leaf, 274
Autogamy, 334
Auto-Puccinia, 550
Avena, 45, 316, 317
Awl-shaped leaf, 272
Awn, 317
Axillary buds, 248
Axillary flowers, 312
Azolla, 502
Bacilli, 12, 14, 566
Bacteria, 14, 26, 566
Ballota, 493
Balm of Gilead, 70
Balsamodendron, 70
Balsam Poplar, 66
Balsam Tree, 193
Balsams, 37, 66, 416, 442,
470, 494
Bamboo, 55, 222, 225
Bambusa, 55, 222
Banana, v, 70
Baneberry, 261
Banyan, 192, 193, 236
Baobab, 181
Barbed bristles, 304
Barberry, 170, 405, 409, 430
Barley, 1, 2, 168
Basal style, 357
Basidia, 544
Basidiomycetes, 537
Basifixed'anther, 356
Bast-fibres, 78
Bast-tissues, 208
Batrachospermum, 557
Bauhinia, 216, 220
Bay-tree, 246
Bean, 26, 169, 172, 214, 226
416
Beard Moss, 529
Bedeguar, 304, 309
Bedstraws, 221, 309
Beech, 250, 305, 489
Bee Orchis, 3, 6
Beetroot, 46, 48
Beggiotoa, 566
Begonia, 248, 272, 324, 326
332
Bellis, 266, 273, 313, 325, 350
Bell-shaped corolla, 342
Berberis, 170, 405, 409, 430
Bermuda-grass, 188
Berry, 486
Bertholletia, 480
Beta vulgaris, 46, 48
Betula, 65, 198, 201, 203, 497
Biennial Plants, 218
Bignoniacese, 493
Bindweed, 235, 317, 329
Bipinnate, 256
Birch, 65, 198, 201, 203
Bird-pollination, 444
Bird's-eye Primrose, 389
Bird's-foot Trefoil, 362
Bird's-nest Fungus, 546
Birthwort, v, 356, 374, 384
Biserrula, 498
Bisexual flowers, 368
Biternate, 261
Bitter Cress, 373
Bitter Cucumber, 496
Bittersweet, 228
Blackberry, 474
Black Horehound, 493, 494
Blackthorn, 224, 229, 300
Blackwood-tree, 232
Bladderwort, 106-112
Bladder Wrack, 562, 565
Blade of leaf, 254
Bleeding Heart, 320
"Blood Portent," 14
" Bloom " of leaves and
fruit, 66
Blue-bell, 332
Blue-bottle, 492
Boehmeria, 62
Bog-moss, 33
Boletus, 544
Bomarea, 126, 132
Bombax, 236
Borage, 394
Borago, 394
Boswellia, 70
Botany, meaning of the
term, 6
Bo-tree, 242
Botrychium, 508, 509
Bottle-tree, 222
Box, 327
Bracken, 504
Bracteate flowers, 314
Bracte, 314
Bramble, 199, 200, 224, 226,
238
Brassica, 58, 169, 180, 289,
295
Brazil-nut, 480
Bread-fruit, 44, 474
Brefeldia, 149, 570, 572
Broom, 187, 188
Broomrape, 151, 153, 155,253
Brown Algfe, 560
Brownea, 444
Brownian Movements, 565
Brugmansia, 445
Brunsvigia, 214, 219
Bryonia dioica, 226, 231
Bryony, Black, 228, 237, 254
Bryony, White, 226, 231
Bryophyllum, 248, 250, 252
Bryophyta, 522
Bubonic Plague Bacillus, 12,
14
Buckbean, 35, 41
Buckler Ferns, 507
Buds : adventitious, 248 ;
axillary, 248 ; epiphyllous,
248 ; root, 248 ; terminal,
248
Bud-scales, 246
Bulbils, 248, 518
Bulbs, 212
Bulrush, 453
Bupleurum, 264, 266, 269
Burweed, 484. 485
Bush-rope, 216, 220
Butcher's Broom, 222
Butcher's Broom Helwingia,
250
Butomus, 26, 31
Buttercup, 179, 181, 317,
321, 333, 340, 342, 368,
409
Butterworts, 102-105, 108
Buttress-tree, 200, 217
Buxus, 327
Cabomba, 281
Cactaceae, 27, 33, 37, 46,
58, 126, 225, 237, 253
Cactus, 27, 33, 46, 58, 288 ;
Old Man, 58 ; Monster,
67, 237
Caducous calyx, 337
Cakile, 186
Caladium, 324
Calamus, 222, 230
Calceolaria, 346
Calceolate corolla, 348
Calendula vulgaris, 138
Calla, 361, 400, 441, 442
Callithamnium, 557
Calluna, 447
Caltha, 362
Calypter, 164, 524
Calystegia, 235
Calyx, 321 ; accrescent, 337 ;
caducous, 337 ; decidu-
ous, 337 ; dentate, 342 ;
galeate, 336 ; globose, 338 ;
persistent, 336 ; saccate,
338 ; spurred, 336; tubular,
338
Cambium, 129, 208
Camellia, 329
Campanula, 342, 347, 361,
425
Campanulacese, 382
Campanulate corolla, 342
Campion, White, 340
Campylotropous ovule, 465
Candle-snuff Fungus, 547,549
Candytuft, 482, 486
€ane, 230
Canna, 45
Canose, 48
•Canterbury Bell, 361
•Caoutchouc, 50
Capillitium, 571
•Capitulum, 318, 350, 554
Capsella, 262, 375, 381, 465,
482
Capsule, 474
Carbon, 57, 93
•Carbon dioxide, 94
Carbonic acid, 94, 96
•Cardamine, 248, 253, 373,
393, 413
Carduus, 302
•Carex, 184, 459
Carina, 350
Carlina, 492
•Carline-thistle, 492
Carludovica, 228
Carnation, 340
Carpels, 321, 332
Carpinus, 461, 497
•Carpogone, 557
•Carpophore, 493, 538
Carrageen, 558
•Carrot, 177, 180- 332, 336
Caryophyllaceae, 66
Caryophyllaceous corolla, 340
•Caryopsis, 488
Cassia, 446
Castdlia, 328, 464
Castanea, 367, 462
•Castor-oil Plant, 58, 498
Catasetum, 408, 409, 435
'Catchfly, 340, 365
Caterpillar-plant, 478, 481
Catkin, 318
Cat's-foot, 265
Caudex, 214
Caudicles, 433
•Cauline leaf, 272
Caulotretus, 218
•Cedar, 83, 84, 85, 242
Cedrus, 83, 84, 85, 242
Celandine, 49, 50, 248
•Celandine, Lesser, 182
Celery, 41
Cell-communities, 73
Cell-division, 9, 73, 76
Cells, 12, 24
•Cells : annular, 36 ; pitted
or dotted, 32 ; reticulated,
36 ; spindle-shaped, 32 ;
spiral, 33, 36 ; spiro-annu-
lar, 36 ; stellate, 28
Cellulose, 29, 54
Centaurea, 262, 325, 364,
371, 377, 492
Ceoma, 552
•Cephaelis, 182
Cephalotus, 6, 116, 279
•Cerasus, 252, 416
•Ceratopteris, 249
•Cereus, 27
INDEX
Ceropegia, 234, 240, 425
Ceterach, 246
Cetraria, 533
Chara, 552, 553
Characeae, 553
Cheiranthus, 318, 338
Chelidonium majus, 49 50
248
Cherry, 252, 256, 257, 313, 416
Chestnut, 28, 240
Chicory, 45, 48
Chlora, 264
Chlorella, 400
Chlorophyceae, 561
Chlorophyll, 38
Ghondrus, 558
Christmas Rose, 195, 246
Chrysanthemum, 350, 352
Cichorium, 45, 48, 269
Cicuta, 70, 72
Cinquefoil, 265, 268
Circcea, 326
Circinate vernation, 250, 508
Circular aestivation, 329
Circulation, 20
Circumnutation, 214, 233
Cirsium, 470
Cistus, 72
Citric acid, 46
Gitrullus, 496
Cladodes, 222
Cladonia, 75, 530, 532
Clarkia, 361
Clary, Wild, 33
Clavaria, 538, 545, 549
Claviceps, 541, 549
Clawed petals, 338
Cleavers, 484
Cleistogamic flowers, 370
Clematis, 20, 78, 226, 234,
326, 328, 335
Climbing Cobaea, 373, 378
Climbing Palms, 230
Climbing plants, 226
Closterium, 565
Clover, 92, 260, 362
Cloves, 66
Club-mosses, 504, 514
Club-rush, 226
Clusia, 193, 194
Cluster Cups, 546, 550
Cluster Pine, 186, 189
Cnicus, 264, 265, 299
Cobcea, 373, 378
Coccus, 566
Coco-nut, 170, 486
Cocos, 170, 486
Coelogyne, 380, 382, 405
Coffea, 170
Coffee, 170
Cohesion, 330
Coix, 490
Colchicum, 476
Collective fruits, 474
Collenchyma, 82
Colt's-foot, 492
579
Columbine, 345, 348, 478
Columel, 506
Comatricha obtusata, 15
Comfrey, 407, 414
Comma Bacillus, 12, 568
Commiphora, 70
Compass-plant, 290
Complete flowers, 369
Composite, 353, 369, 382
Composite flowers, 350
Compound leaf, 254
Compound pistils, 332
Compound umbel, 318
Conceptacles, 561
Conditions of plant life, 178
Conduplicate vernation, 250
Cone, 318
Cone-bearing plants, 36, 66
85, 224
Confervoideae, 562
Coniferce, 36, 66, 85, 173, 224
Conifers, 273
Conjugatae, 564
Conjugates, 564
Conjugation, 76
Conjugation of cells, 76
Connate leaf, 264
Connective, 321, 354
Conspicuousness of flowers ,
390
Convallaria, 210, 314
Convoluta, 38
Convolute vernation, 250
Convolvulaceae, 317
Convolvulus, 329, 342, 345
Coprinus, 163
Corallina, 553, 556, 557
Cordate leaf, 264
Cord Moss, 525
Cordyceps, 156-159, 549
Cork, 13, 31
Corms, 213
Corn-cockle, 45, 269, 474, 496
Corn-spurrey, 269
Cornus, 314, 327
Corolla, 321
Corollas : calceolate, 348 ;
campanulate, 342 ; cary-
ophyllaceous, 340 ; cruci-
form, 338 ; gamopetallous,
342 ; gibbous, 348 ; globose,
348 ; hypocraterif orm, 34 1 ;
infundibuliform, 342 ; labi-
ate, 344 ; ligulate, 352 ;
mitraeform, 349; papilion-
aceous, 352 ; paracorolla,
353; personate, 344; rosa-
ceous, 340 ; rotate, 341 ;
tubular, 341 ; urceolate,
349
Corona, 353
Cortex, 180
Corticium, 545
Coryanthes, 418, 438
Corylus, 416, 456, 488, 491
Corticium, 545
580
INDEX
Corymb, 318
Cosmarium, 565
Cotton-grass, 453
Cotton-plant, 13, 25
Cotton-thistle, 263
Cotyledon, 168
Cowbane, 70, 72
Cowslip, 250, 313, 314, 315
Cow-tree, 53
Cow-wheat, 498
Crab-tree, 264
Cranes-bill, 374, 382, 494
Cratcegus, 224
Craterellus, 548
Creeping fruits, 469
Creeping Loosestrife, 312
Cremocarps, 493
Crenate margin, 265
Cress, 169
Crimson Plume Seaweed, 567
Crithmum, 493
Crocus, 213, 218, 287, 288,
332, 334
Cross-fertilization, 389
Crowfoot, 268, 281, 409,
490
Crow-silk, 73
Cruciferse, 413
Cruciform corolla, 338
Cryptogamia, 500
Cryptogams, 29, 166, 254, 500
Cryptogramme, 504
Crystalloids, 53, 57, 58
Crystal formation and plant
growth contrasted, 2, 60
Crystals, 53, 58, 61
Crystalworts, 529
Cuckoo-flower, 393, 412
Cuckoo-pint, 42, 45, 131, 313,
394
Cucullate leaf, 280
Cucurbita, 337, 489
Culm, 222
Cuneate leaflet, 266
Cup Moss, 530, 532
Cupressus, 242
Cupules, 489
Currant, 250
Cuscuta, 152, 153, 173
Cut-grass, 372
Cyanic flowers, 396
Cyanophyll, 282
Cyathus, 546
Cycads, 88, 89
Cyclamen, 213, 368
Cyclosis, 554
Cylindrical leaf, 269
Cyme, 318
Cynodon, 188
Cypress, 242
Cypripedium, 444
Cypsela, 488, 490
Cystocarp, 559
Cystoliths, 54, 61
Cystopleris, 505
Cytisus, 187, 188
Daffodil, 353
Dahlia, 45
Daisy, 212, 266, 273, 313,
325, 350
Dalechampia, 414
Dammara, 88
Dandelion, 45, 50, 204, 270,
276, 313, 316, 329, 332,
350, 372, 467
Date Palm, 135
Datura, 476
Daucus, 177, 180, 332, 336
Dead-nettle, 354, 362
Deciduous calyx, 337
Deciduous leaves, 273
Decurrent leaf, 264
Decussate leaves, 270
Definite inflorescence, 317,
327
Degradation products, 56
Dehiscence, 356
Dehiscence of anthers : longi-
tudinal, 356 ; porous, 356 ;
transverse, 356 ; valvular,
356
Dehiscent drupe, 482
Dehiscent fruits, 474
Delabechea, 222
Delesseria, 557, 559
Delphinium, 336, 339. 390,
409, 478, 481, 496
Dentate margin, 274
Desmanthus, 281
Desmid, 26, 564
Desmodium, 293, 298
Devil's-fig, 378
Dewberry, 471
Dextrose cumbers, 226
Diadelphous stamens, 332
Dianthus,25, 317, 327, 340
Diastase, 133
Diatomaceae, 565
Diatoms, 26, 565
Dicentra, 318, 320
Dichogamy, 382
Dicotyledons, 78, 172, 206,
209
Dictamnus fraxinella, 141
Digitalis, 333, 343, 378
Digitate leaf, 257
Dioecious plants, 370, 526
Dionoea muscipula, 98, 105
Dioscorea, 212
Dipsacus, 264, 267, 297, 302
Discomyceteae, 548
Distichous leaves, 253
" Division of Labour," 28
Docidium, 565
Dock, 250
" Doctrine of Signatures," 532
Dodder, 152, 153, 173, 253
Dog-lichen, 532, 533
Dog-rose, 44, 254, 301, 333
Dogsbane, 364
Dog's Mercury, 212
Dogwood, 314, 327
Dorsifixed anther, 356
Dorycnium, 476
Dotted Cells, 33
Double Coco-nut, 486, 488
Draba, 289
Dracontium, 284
Dracunculus, 402
Dragon Arum, 141, 400
Dropwort, 182
Drosera, 84, 95, 100, 102-104
Drosophyllum, 101, 105
Drupe, 485
Dryad's Saddle, 197
"Dry rot," 161, 540, 542
Dutchman's Pipe, 425
Dutch Rushes, 512
Earth-ball, 162
Earth-nut, 478, 484
Earth-stars, 537, 546
Ebracteate flowers, 316
Ecballium, 469
Echinocactus , 67
Ectocarpus, 560
Edelweiss, iii, 314
Eel-grass, 450
Elaphomyces, 158, 159, 54 9>
Elaters, 512, 571
Elecampane, 45
Elder, 34
Elk's-horn Fern, viii
Elliptical leaf, 256
Elm, 207, 308
Elodea canadensis, 22, 40
Elymus arenarius, 184
Emarginate, 265
Embryo, 466
Embryo-sac, 466
Enchanter's Nightshade, 326.
Endocarp, 473
Endoderm, 180
Endosmose, 121
Endosperm, 466, 520
Endospore, 518
Entire leaf, 254
Entomophilce, 442
Eperua, 444
Ephedra, 186
Epicalyx, 337
Epicarp, 473
Epidermis, 85, 205
Epigynous flowers, 357
EpHobium, 372
Epipactis, 421
Epiphragm, 526
Epiphyllous buds, 248
Epiphytes, 193
Epiphytic Club-mosses,r51&
Epispore, 510, 518
Equisetaceae, 504, 512
Equisetinse, 504, 512
Equisetum, 78, 512—515
Ercilla, 228
Ergot, 540, 549
Erianthus, 209, 210
Erica, 349
Eriophoron, 453
Er -odium, 423, 424
Eryngium, 184, 186
Erythrina, 444
Eschscholtzia, 337
Essential floral organs, 321,
369
Eucalyptus, 236, 408
Eucalyptus, 231
Euphorbia, 53, 54, 76, 77,
81, 142, 152, 225, 230,
253, 288, 300, 396, 397, 414
Evergreens, 273
Evernia, 52 7
Exalbuminous seed, 170, 468
Exosmose, 121
Exospore, 578
Extine, 466
Extrorse anther, 356
Fagus, 250, 489
Fairy Clubs, 549
Fall of the Leaf, 310
False Cyperus, 459
False Dittany, 141
Fasciation, 309
Fascicle, 318
Ferns, 165, 166, 172, 250,
254, 255, 504
Fertilization, 466
Ferula, 70
Festuca, 302
Feverfew, 45
Fibrill*, 18
Fibro-vascular bundles, 85
Fibro- vascular tissue, 85, 205,
208
Ficus, 61, 192, 193, 242, 246,
248, 386, 397
Fig, 388, 397
Fig, Wild, 160
Figwort, 348, 350
Filament, 321, 356
Filices, 250, 502, 504
Filicinge, 504
Filiform leaf, 268
Filmy ferns, 506
Fir-cone, 253
Fission plants, 12
Fistular leaves, 288
Fixed oils, 54
Flag, 210, 268
Flagella, 9
Flamingo-flower, 399
Flax, 58
Flint, 32
Floral adhesion, 333
Floral envelopes, 321
Floral forms, 312
Floral number, 330
Floral variation, 330
Floral whorls, 330
Florets, 313, 350
Floridea?, 146, 449, 556
Flowering Rush, 26
Flowerless plants, 29, 500
INDEX
Flower odours, 304
Flowers and insects, 312
Foliose Hepatics, 526
Follicle, 478
Fames, 69, 534, 538, 544
Fontinalis, 165
Forget-me-not, 313, 327, 376
Forked Seaweed, 563
Foxglove, 333, 342, 343, 378
Fragaria, 214, 223, 337
Frankincense, 70
Fraxinus, 254, 368, 369
Free cell formation, 76
Fronds, 284
Fuchsia, 61, 310
Fucus, 555, 561, 565
Funaria, 525
Fundamental tissue, 205
Fungi, 85, 160, 166, 172,
254 ; luminous, 143, 147,
148 ; slime, 393
Furcellaria, 563
Furze, 188
Galactodendron, 53
Galanthus, 359, 360
Galbanum, 70
Galeate calyx, 336
Galium, 22 1, 309, 484
Galls, 301-311
Gametangia, 561
Gamete, 466, 537, 561
Gamopetalous corolla, 330
Gamosepalous calyx, 330
Garden Convolvulus, 373,
376, 392, 394
Garrya elliptica, 86, 90
Gasteromycetese, 546
Geaster, 537, 546
Genista, 224, 428
Gentian, 180, 317, 362
Gentiana, 180, 317
Geranium, 374, 382, 494
Germination, 168
Germ-tubes, 537
Gibbous corolla, 348
Gill-by-the-Ground, 265
" Gills," 542
Ginkgo, 88
Gladiolus, 213
Glands, 84
Glandular hairs on calyx,
364
Gleba, 548
Gleditschia, 280
Gleichenia, 249
Glittering Toadstool, 163
Globoids, 53, 57
Globose calyx, 338
Globose corolla, 348
Glomerulus, 318
Gloxinia, 248
Glucose, 49
Glumes, 317
Gluten, 57
Gnaphalium, 6
581
Goafs-beard, 316, 319, 364,
366, 490
Goafs-thorn, 56
Godwinia, 282, 284
Goodyera, 431
Gooseberry, 337
Goose-grass, 484
Gossypium, 13, 446
Gourd, 487, 489
Gramineae, 168, 172, 250, 354
Grape, 463
Grape-sugar, 49
Graphis elegans, 85
Grapnel-plant, 485
Grasses, 181, 211, 250, 261
288, 317, 354
Grass of Parnassus, 354
Grass-wrack, 449
Green Algae, 561
Green Mould, 22
Ground Ivy, 265, 268, 272
Ground-nut oil, 54
Groundsel, 262, 376
Ground tissue, 85, 205
Guard-cells, 125
Gum-arabic Plant, 478, 485
Gum tragacanth, 56
Gymnaic acid, 48
Gymnema, 48, 53
Gymnogramme, 505
Gymnosperms, 88, 89, 496
Gymnosporangium, 551, 552
Gymnostomous sporange, 391
Gynandrous adhesion, 334
Gynoecium, 357
Gyrophora cylindrica, 88
Haastias, 6
Habenaria, 426, 435
Hcematococcus, 8
Hairs of plants, 289, 295
Halesia, 194
Halimeda, 558
Halymenia, 561
Hard-fern, 501, 504
Hard-heads, 371
Hare's ear, 264, 266, 269
Harpagophytum, 485
Hart's-tongue, 249, 504
Hart-truffle, 158, 159, 549
Hastate leaf, 268
Haulm, 288
Hawthorn, 224," 550
Hay Maid, 265
Hazel, 416, 456
Heartsease, 170
Heath, 349, 350
Heather, 447
Hedera, 190, 191, 192, 196,
214, 226, 241, 258
Helianthus, 45,\138, 212
Hellebore, 258, 259, 336
Helleborine, 421
Helleborus, 195, 246, 258, 259,
336
Helminthia, 492
582
INDEX;
Helwingia, 250
Hemlock Spruce, 66
Hemlock Stork's-bill, 423,424
Hemlock Water-dropwort, 63,
72
Henbane, 336, 338, 343, 382
Henbit, 370
Hepatic*, 85, 502, 522, 524
Herbaceous plants, 216, 218
Herb-paris, 261, 313, 314
Herbs, 218
Hermaphrodite flowers, 368
Herminium, 440
Hesperidium, 488
Hesperis, 397
Heteroecism, 550
Heterophyllous leaves, 268
Hetero-Puccinia, 550
Heterostylism, 385
Hcvea, 50
Hilum, 169
Hip, 44
Hippeastrum, 125
Hippophae, 461
Hirneola, 540, 545
Holly, 246, 253, 272, 273,
288, 296, 298, 301
Hollyhock, 329
Holocyclic stems, 220
Honesty, 338
Honey, 406
Honey-flower, 418
Honey-guides, 340, 404
Honey-locust Tree, 280
Honeysuckle, 226, 239, 264,
266, 341, 364
Hook climbers, 226
Hookeria, 145
Hop, 25, 30, 34, 226, 233, 295
Hop Hornbeam, 497
Hop Trefoil, 92
Hordeum, 1
Horehound, 289, 295
Horminum, 391
Hornbeam, 461, 497
Horn of Plenty Fungus, 548
Horse-chestnut, 66, 175, 177,
245-247, 257, 366, 479, 482
Horsetails, 78, 166, 504,
512-515
Humulus,25, 30, 34, 226, 233
Huntsman's-horn, iv
Hyacinth, 213, 218, 396
Hyacinthus, 218, 396
Hydrangea, 351
Hydrogen, 57, 96
Hydrophihe, 448
Hydropteridese, 504
Hymenium, 542
Hymenomycetes, 542
Hymenophyllese, 502, 506
Hyoscyamus, 336,338, 343,353
Hypanthodium, 318
Hypericum, 325, 329
Hyphse, 550
Hyphomycetese, 553
Hypogynous flowers, 357
Hysteriacese, 549
Iberis, 482, 486
Iceland Moss, 533
Ilex, 246, 253, 273, 288, 298,
301
Imbricated aestivation, 329
Impari-pinnate leaf, 256
Impatiens, 37, 372, 416, 442,
446, 470, 494
Imperfect flowers, 369
Incomplete flowers, 369
Indian Crocus, 380, 382, 405
Indian Cups, 113
Indiarubber, 50, 61, 246, 248
Indefinite inflorescence, 317,
381
Indehiscent fruits, 474, 485
Indusium, 504, 506
Inflorescence, 313
Infundibuliform corolla, 342
Infusoria, 26
Innate anther, 356
Inorganic compounds, 129
Insectivorous'plants, 102-120
Integuments of ovule, 465
Intercellular 'spaces, 124
Interfascicular cambium, 209
Internodes, 220
Intine, 466
Introrse anther, 356
Inula, 45
Inulin, 45, 54
Involucre, 316
Involute vernation, 250
Ipomaa, 373, 376, 392, 394
Iriartea, 189
Iridacece, 214
Iris, 61, 210, 214, 268, 476
Irregular flowers, 340
Irregularity of form, 402
Irritability, 430
Isoetes, 502, 518, 520
Italian Reed. 76
Ithyphallus, 61
Ivory-nut, 170
Ivy, 190, 191, 192, 196, 214,
226, 241, 258
Jak-fruit, 39
Jania, 557, 558
Jasminum, 1, 64
Jatropha, 44, 498
Jerusalem Artichoke, 45, 212
Jessamine, i, 64
Jew's-earFungus,540,545,54S
Job's-tears, 490
John-go-to-bed-at-noon, 364
Juglans, 61, 62, 482
" Jumping Beans," 470
Jumping leaf, 249, 251
Juncus, 26
Juniper, 277, 551, 552
Juniperus, 277
Jurinea, 364
Kalmia, vii, 406, 430
Kamschatkan Lily, 462"
Keel, 350
Khus-Khus, 64, 142
Kidney-shaped leaf, 265-
Kidney Vetch, 254
Kieselguhr, 566
Kitasato bacillus, 14
Knapweed, 325, 377
Kon-tree, 202
Labiate corolla, 344
Laburnum, 330
Laciniated leaf, 286
Lactuca, 52, 300
Ladanum, 70
Lady Fern, 71, 167
Lady's Smock, 248, 253
Lady's Tresses, 419
Laminaria, 294, 554, 560
Lamium, 327, 344, 346, 354,.
370
Lanceolate leaf, 254
Land-turtle's Ladder, 216
Lapageria, 444
Laportea, 278, 279
Larch, 80, 85
Larch-leaf Rust, 552
Larix, 80, 85
Larkspur, 336, 339, 390, 409,.
481, 496
Lateral style, 357
Latex, 49, 53
Lathrcea, 118, 120, 121, 123
Lathyrus, 226
Lattice-leaf Plant, 284, 285
Laurel, 416
Laurus, 246
Lavandula, 56
Lavender, 56, 62, 72
Laver, 558
Layer of separation, 310
Leaf-bud, 245
Leaf climbers, 226
Leaf forms, 254
Leafless plants, 254
Leaf nectaries, 416
Lecanora parella, 86
Lecidea, 534
Lecythis, 477
Leersia, 372
Legume, 478
Legumin, 57
Leguminosae, 296
Leitneria, 356
Lens-shaped cells, 86
Lenticels, 129
Leocarpus, 572, 573
Leontopodium, iii, 314
Lepidium, 169
Leptodermis, 496, 498.
Leptothrix, 566
Lessonia, 237, 560
Lettuce, 46, 300
Leukoplasts, 42
Liantesse, 122
Liber, 209
Lichen-forming Fungi, 532
Lichens, ii, 38, 85, 86, 527,
534
Lignin, 29
Ligulate corolla, 350
Ligule, 254
Ligustrum, 264, 269, 270, 327
Lilac, 270, 377
Lilium, 138, 314, 409
Lily, 172, 213
Lily of the Valley, 210, 314
Lime-galls, 306, 309
Lime-secreting plants, 556
Lime-tree, 57, 61, 84, 242,
280, 317, 329
Linaria, 344, 349, 481, 483
Linear leaf, 254
Linseed-oil, 58
Linum, 58
Lip-cells, 506
Liriodendron, 246, 250, 274
Lislera, 401, 420, 421
Lithothamnium, 556, 558
Liverworts, 85, 126, 134, 166,
172, 522, 524, 528
Lobelia, 332
Loculi, 476
Loculicidal dehiscence, 476
Lodoicea, 486
Lomaria, 501, 504
Lomentum, 478, 485
London Pride, 266, 271
Lonicera, 239, 264, 266. 341,
364
Loosestrife, 312
Loranthaceae, 233
Loranthus, 176
Lotus, 362
Lousewort, 361, 365
Lucerne, 266, 482
Luminosity of plants, 137-
151
Luminous Mosses, 142
Lum-tree, 200
Lunaria, 338, 485
Lungs of Oak, 532
Lupins, 289, 294
Luzula, 318
Lychnis, 340, 474, 496
Lycogala miniata, 16
Lycoperdon, 535, 546
Lycopodiaceae, 504, 514
Lycopodinse, 504
Lycopodium, 501, 514-517
Lyme-grass, 181, 184
Lyrate leaf, 269
Lysimachia, 312
Lythrum, 363, 377, 378, 386
Macrocystis, 237, 560
Madder-plant, 125
Madwort, 289, 295
Magnolia, 379, 382, 478
Maidenhair Spleenwort, 500
Maiden Pink, 340
INDEX
Maize, 169, 173
Malacophilae, 442
Malcolmia, 25
Male Fern, 502, 503
Malic acid, 48
Mallow, 270, 336, 494
Malva, 270, 336, 494
Mamillaria, 33
Mamures, 228
Mandioc-root, 54
Mandragora, 180
Mandrake, 180
Mangrove, 200
Manihot, 54
Manubrium, 554
Maple, 173, 178, 180, 198, 493
Marattiaceae, 508
Marcgravia, 229, 445
Marchantia, 126, 134, 528
Marchantiaceaa, 526
Marigold, 138; African, 138
Maritime Pine, 68, 186
Marjoram, 60, 64
Marram, 181, 184, 185, 188,
212, 292
Marrubium, 289
Marsh Cypress, 202
Marsh Marigold, 362
Marsilea, 285, 512
Martagon Lily, 138, 409
Martynia, 482
Marvel of Peru, 289, 295
Masterwort, 261
Mat-grass, 302
Matthiola, 481, 482
Matricaria, 45
Matweed, 292
May-tree, 224
Meadow-cranesbill, 374, 382
Meadow-crocus, 287, 288
Meadow-rue, 256
Meadow-saffron, 476
Meadow-sweet, 323
Medicago, 266, 478, 482
Medick, 266
Medlar, 473, 475
Medulla, 208
Medullary rays, 208
Medullary sheath, 78
Megarrhiza, 466
Megasporange, 510
Megaspore, 510
Melampsora, 552
Melatnpyrum, 498
Melianthus, 418
Melocactus, 33
Melon, 337
Mentha, 57
Menyanlhes, 35, 41
Mericarps, 492
Mericyclic stems, 220
Meristem, 82
Merulius, 540, 542
Mesembryanthemum, 4, 6, 86
Mesocarp, 473
Mesophyll, 502
583
Mespilus, 475
Metabolism, 54
Metrosideros, 232
Micrasterias, 565
Micrococcus, 566
Micropyle, 169
Microsporange, 510
Microspore, 510
Midrib, 256
Mignonette, 332, 397
Milk-sap, 49, 52
Milk-thistle, 489
Mimosa, 21, 292, 296
Mint, 56
Mirabilis, 289
Mistletoe, 36, 37, 150, 153, 233
Mitraeform corolla, 349
Mitrula, 545
Mnium, 136
Molucella, 336
Monachanthus, 436
Monadelphous stamens, 332
Moneywort, 312
Moniliform pod, 478
Monkey-ladder, 218
Monkey-nut, 58
" Monkey-pots," 477
Monkshood, 180, 260, 262,
336
Monocotyledons, 78, 1 72, 209-
Monoecious plants, 370, 526
Monosymmetrical flowers, 340
Monstera, 133, 136, 285, 286
" Monstrous " flowers, 326
Moonwort, 508
Mora, 236
Mora-tree, 236
Morchella, 160, 164, 543, 548-
Morel, 160, 164, 543, 548
Morning Glory, 373, 376
Morus, 474
Moss " flowers," 514
Mosses, 85, 134, 136, 162,
165, 166, 168, 172, 254,
522, 525 ; luminous, 142,
145
Mossy Pink, 344
Motile plants, 10
Moulds, 22, 534, 536
Mountain-ash, 401
Mucor, 534, 537, 550
Mucilago, 568, 572
Mucronate leaf, 266
Mulberry, 473, 474
Mullein, 289, 291
Multicellular plants, 10
Murlins, 558
Musa, v, 70
Musci, 85, 134, 162, 522
Mushroom, 24, 147, 160, 161,
530
Mustard, 168, 269
Myanthus, 436
Mycele, 530, 540
Mycetozoa, 568
Mycorhiza, 540
584
INDEX
Myosotis, 313, 327, 370, 374,
396
Myristica, 496
Myrrh, 70
JMyxogasters, 149, 568
jMyxomycetes, 568
Narcissus, 353
Nardus, 302
Nasturtium, 139, 141, 226,
336, 337, 409, 494
Xectar, 406
Xectaries, 390, 398, 409
Xeedle-shaped leaf, 273
Xegro's-head Palm, 1 70
Nelumbium, 272, 276
Neottia, 437
Nepenthes, 107, 110-118, 279
Nepeto, 265, 268, 272
Nephrodium, 507
Nettles, 61, 212, 296, 303,
304, 305, 460
Net- veined leaf, 256
Neuropeltis, 317
Xeuter flowers, 369
Xew Holland Pitcher- plant,
113
Nicandra, 289, 295
Xight-flowering Stock, 397
Nitella, 16, 553
Xitrogen. 57, 97
Xodes, 220
Xon-nitrogenous compounds,
57
Xorfolk, or four-course rota-
tion, 93, 100
Xucellus, 465
Xuclear di\-ision, 74
Xucleoplasm, 18
Xucleus, 17, 569
Nut, 486
Xutmeg, 496
Xutrition, 92
Nymphcea, 328
Nymphseacese, 170, 468
Oak, 23, 24, 28, 32, 59, 66,
173, 240-244, 257, 260
452, 489, 495
Oak-galls, 301-311
Oak, Cowthorpe, 241 ; Green-
dale, 240, 242 ; in Xor-
mandy, 240 ; Salcey, 240 ;
Winfarthing, 240, 244
Oar- weed, 294
Oat, 45, 316, 317
Obcordate leaflet, 265
Oblique leaf, 272
Oblong leaflet, 266
Obovate leaf, 264
Obtuse apex, 274
Octastichous leaves, 253
Odontoglossum, 412
(Enanthe crocata, 63, 72
2
Sporophyte, 510
Sprossglied, 220
Sweet Pea, 226
Sweet William, 327
Spruce, 69, 309
Sword-shaped leaf, 268
Spur, 336
Sycamore, 270
Spurse, 53, 54, 77, 81, 152,
Symbiosis, 532
225, 230, 300, 396, 397, 414
Symphoricarpus, 25
Squirting Cucumber, 469
Symphytum, 407, 414
Stamens, 321
Syncarp, 474
Staminate flowers, 369
Syncarpous pistils, 333
Staminodes, 412
Synergidae, 466
Standard, 350
Syngenesious stamens, 332
Stangeria, 88, 502
Syringa, 270, 341, 377
Stanhopea, 440
Starch, 42, 45, 54
Tabasheer, 62
Star of Bethlehem, 213, 217
Tacsonia, 445
Star-thistle, 262
Tagetes, 138
Stele, 178
Tamus, 237, 254
Tangs, 560
Tannin, 66
Tapioca-plant, 44 ; S. Afri-
can, 81
Tap-roots, 180
Taraxacum, 45, 50, 204, 270,
313, 316, 332, 350, 467
Tassel-grass, 449
Taxus, 79, 85, 242, 465, 496
Teasel, 264, 267, 297, 302
Telegraph-plant, 293, 298
Teleutospores, 550
Tendrils, 226
Terebinth, 66
Terminal buds, 248
Terminal flowers, 312
Terminal style, 357
Ternate, 260
Testa, 169
Tetraspores, 557
Teucrium, 460
Thalamus, 473
I Thalictrum, 256
Thallasiophyllum, 286
Thalloid Hepatics, 526
Thallophyta, 238, 530
Thallus, 533
Thelephorea?, 544
Thistle, 302
Thorn-apple, 476
Thorns, 224
Thorow-wax, 264
Thread-moss, 136
Thyme, 61, 62
Thymus, 61
Thyrsus, 318
Tilia, 57, 61, 242, 280, 317,
329
Tilletia, 553
Tissues, 76, 81
Ti-tree, 232
Toadflax, 344, 349, 362, 483
Toadstool, 530, 538
Tobacco, 70
Toothed capsules, 474
Toothwort, 118, 120, 121, 123
Tortilla, 521, 525
Touch - me - not - Balsam, 37,
372
Tous-les-mois Starch, 45
Tower Mustard, 268
Tracheides, 85
Tradescantia, 17, 20,289
Tragopogon, 316, 364, 366
Transfusion tissue, 88
Transpiration, 128
Trapa, 281
Travellers' Joy, 20, 78, 226
Tree-fern, 232
Trees, 218
Trefoil, 260
Tremella, 544, 545
Trentepohlia, 5ti2
Triadelphous stamens, 332
Trichia, 569, 573
Trichogyne, 558
588
INDEX
Trifolium, 92, 260, 362, 478
Triglochin, 461
Trigonia, 496, 498
Trimorphic flowers, 386
Tripinnate, 256
Tripoli, 566
Tristichous leaves, 253
Triternate, 261
Triticum, 91, 171, 181, 186,489
Tropceolum, 139, 141, 226,
272, 294, 336, 337, 409, 494
Truffle, 549
Trumpet-flower, 22, 493
Trumpet-leaves,' 113
Truncate leaf, 274
Tuber, 549
Tubers, 181, 212
Tubular calyx, 338
Tubular corolla, 341
Tufted hairs, 289
Tulip-tree, 246, 250, 274
Tumboa, 240
Turbellaria, 38
Turnip, 180
Turpentine, 64
Turritis, 268
Tussilago, 492
Twayblade, 401, 420, 421
Typha, 286, 288, 453
Ulex, 188
Ulmus, 207, 308, 493
Umbel, 318
Umbellifera?, 72, 180
Unicellular plants, 8, 10, 26
Upas-tree, 54
Urceolate corolla, 349
Urceolate receptacle, 336
Urchin-crowfoot, 490
Uredinefe, 537, 550
Uredospores, 550
Urocystis, 553
Urtica, 303, 304, 305, 414, 460
Urticaceae, 61
Usnea, 529, 534
Ustilaginete, 552
Ustilago, 553
Utriciilaria, 106-112
Utricular vessels, 80
Vaccinium, 274, 344, 349, 356
Vacuoles, 46, 569
Vagine, 524
Valerian, 341, 348
Valeriana, 341, 348
Vallisneria, 21, 37, 38, 413,
414, 450
Valvular dehiscence, 356, 476
Variation, 278, 330
Vascular bundles, 502
Vascular Cryptogams, 501,
540
478
Vascular cylinder, 1 78
Water-thyme, 20, 22, 40
Vaucheria, 13, 16
Wax, 69
" Vegetable Caterpillar," 157,
" Weeping " of Grape-vines,
158
78
"Vegetable Coastguards,"
181
Wellingtonia, 236
Welwiischia, 240, 241
"Vegetable Ivory," 170
Weymouth Pine, 69
" Vegetable Sheep," 5, 6
Wheat, 25, 91, 166, 171, 181,
,489
" Vegetable Stones," 4, 62
489
226,
Venus' Fly-trap, 98, 105
Wheat Mildew, 550
494
Veil, 544
Wheel-shaped corolla, 341
Verbascum, 289, 291
Whitlow-grass, 289, 295
Verbena, 356, 362
Whorls, 269
Vernal-grass, 261, 264
Whortleberry, 274, 344, 349,
Vernation, 250
356
Veronica, 414
Willow, 68, 220, 246, 276,
Versatile anther, 354
496, 498
Vertical leaves, 290
Willow-herb, 372, 497
Verticillaster, 318
" Wind Witches," 472
Verticillate leaves, 269
Winged fruits and seeds, 493
Vervain, 356
Wings, 350
Vessels, 76 ; annular, 77 ;
Winter Cherry, 337, 341, 396
laticiferous, 80 ; pitted, 77 ;
Wistaria, 324, 326
reticulated, 77; scalariform,
Witches' Broom, 309
78 ; spiral, 77 ; utricular,
Wood-anemone, 316, 417
80
Woodruff, 221, 227
Vetch, 256, 258
Woodrush, 418
1
Vexillum, 350
Wood-sage, 460
Vibrio, 566
Woodsia, 169
Vicia, 26, 214, 256, 268, 416
Wood-sorrel, 51, 172, 214,
Victoria, 282, 283
221, 265, 290, 296, 372,
Vine, 226, 310, 344, 349, 463
373, 468, 469
Vine-galls, 310
Viola, 170, 250, 254, 264,
Woody Nightshade, 273, 302,
346
26
332, 358, 372, 392, 410, 478
Woody stems, 218
Violet, 250, 254, 264, 332,
Wracks, 148, 560
358, 372, 410, 478, 553
Virginia Creeper, 226, 232,
A fit
Xanthic flowers, 396
4U1
Virginian Spiderwort, 17
Virginian Stock, 25
Viscum, 36, 37, 153
Xanthium, 484, 486
Xylaria, 547, 549
Xylem, 88, 209, 501
460
Vitis, 226, 232, 310, 344,
349, 463
Yam, 212, 214
Volatile oils, 62
Yeast, 134
Volva, 544
Yellow Vetchling, 226
Volvox, 8, 10, 562
Yellow-wort, 264
Vorticella, 8, 10, 560
Yew, 79, 242, 496, 497
Yoke-threads, 564, 566
Wake-robin, 42, 131
Yucca, 410, 411, 439, 448
356
Wallaba-tree, 444
Wallflower, 318, 338
Zea, 169, 173
Walnut, 61, 62, 482
Zinnia, 394
Water-caltrops, 281
Zoochlorella, 562
Water-crowfoot, 268, 281, 378
Zoophila?, 448
413,
Water-ferns, 166, 504
Zoospores, 10, 537
Water-lily, 170, 281, 283,
Zostera, 449
476
328, 464
Zygnema, 74, 564, 566
Water-moss, 165
Zygomorphic flowers, 340
Water-pimpernel, 264
Zygomycetes, 537
501,
Water-smartweed, 66
Zygosperm, 537, 564
Water-stomata, 125
Zygote, 561
Printed by Hazell, Watson & Viney, Ld., London and Aylesbury.
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