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—tho key, by means of which every variation of 
form, however remarkable, every deviation from 
type, however wide, every abnormality, however 
apparently capricious, may be referred to a 
common and well-known elementary standard 
by conlrast with which its deviations may be 
measured and its abnormality explained. 
It is in the comparison of parts and i, careful 
study of the relations which they bear to each 
vation many species “ double as the garden¬ 
ers say—and this is done by stamens changing 
back into petals. Tho Fuchsias often give fine 
illustrations of the plasticity of these organs as 
they are molded by tho hands of man. Stamens 
are but changed petals, and petals are leaves. 
In the same way wo can sea that pistils are also 
leaves. Fig. 3 represents two regular leaves a. 
and d. and two simple pistils b. and c,, and it is 
soarcely necessary to add that a leaf with its 
edges folded in and united, makes the ordinary 
female organ of the flower. Monstrosities are 
often found where, from some unknown cause, 
ordinary Jeaves have taken tho place of pintils, 
showing that tho pistils havo reverted to the 
simple element from which they had been differ¬ 
entiated. Wo thus arrive at tho structural 
nature of a flowor through tho study of com¬ 
parative morphology, and express our result in 
the following tonus: A flower is a metamor¬ 
phosed axis, with its metamorphosed leaves. 
We now come to a consideration of the 
FUNCTION WHICH THE FLOWER FULFIlLS 
in the economy of the plant. Functionally a 
flower is a structure by means of which ono 
plaut individual acts upon another for the pro¬ 
duction of a third. In the elaboration of this 
theme wo must see, iu the first place, what is 
understood by the term individual, as used 
among plants. Among tho higher anim»ls ihe 
conception of an individual is clear and well de¬ 
fined. With lower animals such is not the case, 
where, as iu the coralM, many individuals remain 
attached to each other through life, and exist as 
a community of individuals. Among plants the 
unit is often still more difficult to determine, 
and upon this point some difference of opinion 
is still held. Some have considered all that re¬ 
sults from a tingle Beed as a single individual, 
but this would make all our Weeping Willows an 
individual, because they are propagated entirely 
by cuttings in this country. Likewise each 
variety of fruit which is propagated in like 
manner, is but a single individual, though there 
may be millions and millions of treoa. Another 
view, and the one generally accepted is, (hat a 
plant unit is that smallest part which, in general, 
will live and grow when separated from its 
/firmer place in a plant c&bimunily, and given 
the fitting conditions fur growth by itself. To 
snob a plant individual tho term “ pbyton ” has 
been given, and it consists of a node with its 
leaf and bud and iuteruode. A cion is often 
such an individual. The gardener divides his 
young branches of Verbena, etc., into these pby- 
tons, and places them in moist sand, where they 
begin an independent existence. With this view, 
a tree or shrub is a community of individuals, 
each one of which id joined to, and iu great 
measure dependent npou, thodo arouud it, and 
often assigned some particular office in the com¬ 
bined labors of tho community. 
It is not ditfionlt for us to carry our idea of a 
plant individual to tho flower which we have 
previously seen to consist of simply stem and 
leaves—a stmmou with its portiou of the stem is 
an individniB and tho same with the pistil. 
Fig. 4 represents the division of a plant into its 
loaf—the female—to produce a new individual 
—the seed. 
HOW THE SEED IS PRODUCED 
is the question for us now to consider. The 
stamen has a work to do widely different from 
that of exposing a large surface of green to the 
air and Buuehine; so that the cells beneath the 
epidermis of the anther, in place of containing 
chlorophyl grains—those bodies which give 
the green color to vegetatiou—have pollen 
THE STRUCTURE AND FUNCTION OF 
FLOWERS. 
BYRON D. HALSTEAD 
ANCIENT AND MODERN IDEAS DF FLOWERS. 
There are perhaps no objects in nature whioh 
have received more attention than flowers. They 
are tho emblems of purity and beauty, whioh 
cheer the sick, gladden the hearts of the sad, 
give the last touched cf charm and beauty to the 
bride, and fall as the fitting tribute of love upon 
tho coffin at the open grave. The part flowers 
play in the culture aud expression of the finer 
nature of man wo all know full well, and we 
must not pause to dwell upon a subject whioh 
has been tho theme of admiration and poetic 
praise since tho world began. 
If we could present the ideas of the nature of 
flowers, which have been held by great scien¬ 
tific men iu tho successive ages of the past, we 
would have one of the best illustrations of pro¬ 
gress in human investigation aud evolution in 
human thought. Not long ago flowers were 
considered as parts of plants for decoration only. 
Even Linmnud, the great Swedish naturalist 
aud the acknowledged Father of liotany, of 
whom it has been well said: “Ho was one of 
that handful of man whoso appsarance in all 
ngos of tho world has marked an ora in philoso¬ 
phy—ono of those human land-marks whose 
personal history is the history of sciouce ”—oven 
he, living only a century ago, held to the idea 
that the calyx of the flower was the outer bark, 
the corolla the inner bark, the stami us the 
wood, and the pistils the pith of a floral stem. 
In this transformation of parts wo see the first 
glimpse of that idea which was soon to dawn as 
bright aud clear as a cloudless morning in June. 
This was the advent of tho full conception of 
Morphology, born of one of Germany’s greatest 
poets, Gootho, and sot forth at length in his 
immortal work, “The Metamorphoses of Plants.” 
Goethe reduced all parts of plants to leaf and 
axis, and showed that all organs, whatever they 
may be, are but these shaped aud adapted to the 
functions they are called upon to perform. It 
was not until nearly a century laier, upon the pub¬ 
lication of Darwiu’s work on the “ Origin of Spe¬ 
cies,” in 1850, that tho law of morphology came 
boldly to tho front, and was so clearly and thor¬ 
oughly presented that it at once commanded 
and received the attention of scientific men. 
Before this, tho students of nature had been 
toiling for ages in accummulating facts, and 
now a theory was given founded on those faota 
as viewed in the light of the law of morphology 
RSANA LUXCKIAN3—“ TKOSINTE.” 
grains. Figure 2 shows a part of an or¬ 
dinary leaf above and a portiou of anther 
below. These pollen grains represent the male 
element in floweriug plants and consist of Btnail 
roundish masses of protoplasm (Fig. 2, c, d, e 
and /,) provided with two protecting coats of 
oefiulose, tho outer often beautifully marked 
with bands and spines. This pollen is the “ ferti¬ 
lising dust” of flowers, and, when mature, 
oscapes into tho air through a rupture iu the 
anther sacs. The production of those pollen 
graiuB is the aim and end of all stamens, and 
when this is done, they wither away and soon 
cease to be. 
The pistil is a specialized organ also, consisting, 
when of a simple form, of a single leaf, with its 
edges folded iu and united, thus forming an in¬ 
closed space called the ovary, above which the 
leaf is prolonged into the style and terminates 
in the Btigma. Along the infolded edges of that 
portion of the loaf whioh makes the ovary, small 
bodieB are produced whioh have received the 
name of ovules. Each ovule is an outgrowth 
from tho leaf-edges, and consists of two coats of 
cellular tissuo, not quite inclosing a mass of 
cells, within the central one of which is the 
embryo sac, which contains a little globule of 
protoplasm, the embryonal vesicle. (See Fig. 5 ) 
This is tho female element of flowering plants. 
Pollen grains and embryonal vesicles are thus 
tho sexual elements. The pollen grains are 
small masses of highly endowed protoplasm, 
formed from the central cells of stamiuate 
leaves, which, by the breaking away of the sur¬ 
rounding membrane, are set at liberty from the 
male phyton which has produced them. The 
embryonal vesicles are also peculiarly vitalized 
masses of protoplasmic matter borne iu the 
center of protecting layers of cellular tissue, aud 
are not sot free from the female individual which 
produces them. 
SEXUAL ACTION IN FLOWERING PLANTS 
consists ia tho union of the contents of a pollen 
grain with that of an embryonal vesicle, aud is 
called fertilization, and is brought about, first by 
transfer of the pollen from the anther where it 
is produced to the sticky, receptive surface of 
the stigma—pollination—secondly, in the growth 
of a tube from the pollen grain, down through 
the style to the embryo sac. where the contents 
of the grain—by moans of the tube—pass by 
osmose, or membrane diffusion, into the female 
oell. It is, then, through this portable mass of 
protoplasm that one plaut individual acts upon 
another for tho production of a third. This 
third and new individual ia the embryo piautlet 
which develops from the embryonal vesicle 
which has been stimulated into new growth by 
the pollou grain, whose contents have mingled 
with its own, and when the proper time comes 
the little individual, provided with fool and 
protection, is thrown off from the parent com¬ 
munity to begin a now colony and thus continue 
the species. The end of the flower is tho seed ; 
and the esaeutial organs in the production of 
the seed are the irtamons and pistils. The end 
of the seed is the beginning of a new commu¬ 
nity of plant individuals, all working together 
for the same common end—the production oC 
new seeds. 
And thus seed time and harvest do not 
fail, and the cycles of life move constantly 
forward. 
1 
Fig. 4—Plant with floral parts separated, a. 
bract; o. sepal; c. sepal; d. stamen ; e. pistil. 
Fig. 6.— A. pistil of Buckwheat with ovary and 
ovule divided lengthwise; a. embryonal sac 
w ith lta embryonal vesicle b.; pollen tube at 
c.; d. pollen with tube free (after Graj); B. 
ovary or Funkla very much enlarged; a. and b. 
the youug coals; c. embryonal sac with vesicle 
(after Sachs). 
other, and the special purpose which each modi¬ 
fication subserves, that the moat interesting and 
ennobling Btudy lies. With these principles be¬ 
fore us let us consider 
THE flOWER IN A STRUCTURAL POINT OF VIEW. 
In a complete and porroet flower, like that of 
tho Lily, Apple or common flax (Fig. 1), we have 
an outer whorl, with its separate or united parts, 
as the case may bo, doing tho duty of support- 
iug or protecting the parts within. It is often 
of a greon color, and thus shares with the ordi¬ 
nary foliage the important work of assimilating 
food for the growth of tho plant. Next within 
is the corolla, with its usually conspicuous petals 
or lobes. Within the corolla is the next whorl 
of organs, tho andrcecium, made up of the 
stamens, tho male organa of the plant. At the 
center, surrounded by the calyx, corolla and 
audroccium, is the gynaecium, consisting of one 
or more pistils, tho female parts. 'These four 
parts, which are shown iu section i n a flax flow¬ 
er, in fig. I, make up what the child as well as 
the botanist recognizes at once as a flower. But 
what is the nature of these strangely-formed 
and highly-colored parts ? If all parts of plants 
are reduced to leaf and axis, our flower must bo 
one or the other, or a combination of these two. 
Iu an ordinary Btern, as any which wo might cut 
from an apple Or willow tree, we fluff there is an 
axis—the atom, with certain expansions upon 
it—the leaves. The axis may be long and the 
leaves widely separated upon it, as in a twining 
hop vine ; or it may be reduced to tho shortest 
possible length, and hid from view by tho nu¬ 
merous closely-paokod loaves npou it, as in the 
house look, lily bulb, or any stem while It is in 
the bnd condition. In every flower there is an 
axis, however short, upon which the floral or¬ 
gans are borne. It remains to bo seen that these 
organs are leaves. There is no doubt about tho 
calyx ; in general it is Joaf-Jiko in shape and func¬ 
tion. Tho petals are “ tho leaves of tho flower,” 
but are usually of other than a green color. 
But many true leaves have bright colorB, as 
those of the Coleus, Poiusettia ami many other 
common greenhouse plants. The true loaves of 
tho Pitcher-plant aud Venus’s Fly Trap, are 
more curious in shape than almost any petals. 
The sepals and petals aro leaves ; but how as 
regards the stamens ? Tho cases are numerous 
where we find all gradations between petals and 
these male organs of tho flower. The white 
Water-lily illustrates thiB in nearly every one of 
its large, showy flowers. (Fig. 2, a). Under culti- 
Pkakl Millet in Frpit from I.ifk, 
phytons, tho upper ones of whioh are floral in¬ 
dividuals. We have said one individual in the 
flower acted upon another for the production of 
a third. The stamiuate leaf is one such indi¬ 
vidual—the male—whioh acts upon the pistillate 
