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The second element in the triune political structure is thus, like
the first, developed by militancy. By this the ruler is eventually sep-
arated from all below him ; and by this the superior few become
integrated into a deliberative body separated from the inferior many.

That the council of war, formed of leading warriors who debate in
presence of their followers, is the germ out of which the consultative
body arises, is implied by the survival of usages which show that a
political gathering is originally a gathering of armed men. In har-



COXS UL TA TI VE B ODIES.



353



inony with this implication are such facts as that, after a compara-
tively settled state has been reached, the power of the assembled peo-
ple is limited to accepting or rejecting the proposals made, and that
the members of the consultative body, summoned by the ruler, who
is also the general, give their opinions only when invited by him to
do so.

Nor do we lack clews to the process by which the primitive war-
council grows, consolidates, and separates itself. Within the warrior-
class, which is also the land-owning class, war produces increasing dif-
ferences of wealth, as well as increasing differences of status ; so that,
along with the compounding and recompounding of groups which
war brings about, the military leaders come to be distinguished as
large land-owners and local rulers. Hence, members of the consulta-
tive body become contrasted with the freemen at large, not only as
leading warriors are contrasted with their followers, but, still more, as
men of wealth and authority.

This increasing contrast between the second and third elements of
the triune political body ends in separation when, in course of time,
war consolidates large territories. Armed freemen scattered ovef* a
wide area are deterred from attending the periodic assemblies by cost
of travel, by cost of time, by danger, and also by the experience that
multitudes of men, unprepared and unorganized, are helpless in pres-
ence of an organized few, better armed and mounted, and with bands
of retainers. So that, passing through a time during which only the
armed freemen living near the ])lace of meeting attend, there comes a
time when even these, not being summoned, are considered as having
no right to attend ; and thus the consultative body becomes completely
differentiated.

Changes in the relative powers of the ruler and the consultative
body are determined by obvious causes. If the king retains or ac-
quires the repute of supernatural origin or authority, and the law of
hereditary succession is so settled as to exclude election, those who
might else have formed a consultative body having coordinate power
become simply appointed advisers. But, if the king has not the pres-
tige of supposed sacred origin or commission, and continues to be elec-
tive, then the consultative body retains power, and is liable to become
an oligarchy.

Of course, it is not alleged that all consultative bodies have arisen
in the way described, or are constituted in like manner. Societies,
broken up by wars or dissolved by revolutions, may preserve so little
of their primitive organizations that there remain no classes of the
kinds out of which such consultative bodies as those described arise.
Or, as we see in our own colonies, societies may have been formed in
ways which have not fostered classes of land-owning militant chiefs,
and therefore do not furnish the elements out of which the consulta-
tive body, in its primitive shape, is composed. Under conditions of
roL. XIX. — 23



354 ^^ilE POPULAR SCIEXCE MONTHLY.

these kinds the assemblies answering to them, so far as may be in
position and function, are formed under the inliuence of ti-aditiou or
example ; and in default of men of the original kind are formed of
others — generally, however, of those who, by position, seniority, or
previous official experience, are more eminent than those forming pop-
ular assemblies. It is only to what may be called the normal consul-
tative body which grows up during that compounding and recom-
pounding of small societies into large ones which war effects that the
foregoing description applies ; and the senates, or superior chambers,
which arise under later and more complex conditions, may be consid-
ered as homologous to them in function and composition so far only
as the new conditions permit.



OX FRUITS AXD SEEDS.*

By Sir JOHN LUBBOCK, F. R. S.

IX a very large number of cases the diffusion of seeds is effected by
animals. To this class belong the fruits and berries. In them an
outer fleshy portion becomes pulpy, and generally sweet, inclosing
the seeds. It is remarkable that such fruits, in order, doubtless, to at-
tract animals, are, like flowei's, brightly colored — as, for instance, the
cherry, currant, apple, peach, plum, strawberry, raspberry, and many
others. This color, moreover, is not present in the unripe fruit, but is
rapidly developed at maturity. In such cases the actual seed is gener-
ally protected by a dense, sometimes almost stony, covering, so that it
escapes digestion, while its germination is perhaps hastened by the
heat of the animal's body. It may be said that the skin of apple and
pear pips is comparatively soft; but then they are imbedded in a
stringy core, which is seldom eaten.

These colored fruits form a considerable part of the food of mon-
keys in the tropical regions of the earth, and we can, I think, hardly
doubt that these animals are guided by the colors, just as we are, in
selecting the ripe fruit. This has a curious bearing on an interesting
question as to the power of distinguishing color possessed by our an-
cestors in bygone times. Magnus and Geiger, relying on the well-
known fact that the ancient languages are poor in words for color, and
that in the oldest books — as, for instance, in the Yedas, the Zend-
Avesta, the Old Testament, and the writings of Homer and Hesiod —
though, of course, the heavens are referred to over and over again, its
blue color is never dwelt on, have argued that the ancients were very
deficient in the power of distinguishing colors, and especially blue.
In our own country Mr. Gladstone has lent the weight of his great

* Continued from page 1 V 1 .



ox FRUITS AND SEEDS.



355



authority to the same coiichision. For my part I can not accept this
view. There are, it seems to me, very strong reasons against it, into
which I can not, of course, now enter ; and, though I should rely main-
ly on other considerations, the colors of fruits are not, I think, with-
out significance. If monkeys and apes could distinguish them, surely
we may infer that even the most savage of men could do so too.
Zeuxis would never have deceived the birds if he had not had a fair
])erception of color.









ia.H.—a.h\iT<locU(Lappa): b. agrimovy (Agrimonia) ; chnrpsirsXey (Caucalis); d, enchanter's
uiyh'shade (Circaa) ; e, cleavers {Galium) ; /, forget-me-nota (Myosotin).



In these instances of colored fruits, the fleshy edible part more or
less surrounds the true seeds ; in others the actual seeds themselves
become edible. In the former the edible part serves as a temptation
to animals ; in the latter it is stored up for the use of the plant itself.
When, therefore, the seeds themselves are edible they are generally
jirotected by more or less hard or bitter envelopes, for instance the



356 THE POPULAR SCIENCE MOXTHLW

horse-chestnut, beech, Spanish chestnut, wahnit, etc. Tliat these seeds
are used as food by squirrels and other animals is, however, by no
means necessarily an evil to the plant, for the result is that they are
often carried some distance and then dropped, or stored up and for-
gotten, so that in this way they get carried away from the parent tree.

In another class of instances animals, unconsciously or unwillingly,
serve in the dispersion of seeds. These eases may be divided into two
classes, those in which the fruits are provided with hooks, and those in
which they are sticky. To the first class belong, among our common
English plants, the burdock {Lappa, Fig. 14 a), agrimony (Ar/rinio-
nia, Fig. 14 b) ; the bur parsley {Caucalis, Fig. 14 c) ; enchanter's
nightshade {Circcea, Fig. 14 d) ; goose-grass or cleavers {Galixan,
Fig. 14 e), and some of the forget-me-nots {Mi/osotis, Fig, 14 /").
The hooks, moreover, are so arranged as to promote the removal of
the fruits. In all these species the hooks, though beautifully formed,
are small ; but in some foreign species they become truly formidable.
Two of the most remarkable are represented on page 357 — Martynin
prohoscidea (Fig. 15 b) and Ilaipogophyton j^^'ocumbens (Fig. 15 a).
Martynia is a plant of Louisiana, and if its fruits once get hold of an
animal it is most difficult to remove them. Harpagophytum is a South
African genus. The fruits are most formidable, and are said some-
times even to kill lions. They roll about over the dry plains, and, if
they attach themselves to the skin, the wretched animal tries to tear
them out, and sometimes getting them into his mouth perishes miser-
ably.

The cases in which the diffusion of fruits and seeds is affected by
their being sticky are less numerous, and we have no well-marked in-
stance among our native plants. The common plumbago of South
Europe is a case which inany of you no doubt have observed. Other
genera with the same mode of dispersion are Pittosjyoriim, Plsonia,
Boerhavia Siegesbeckia, Grin-delia, Drymaria, etc. There are com-
paratively few cases in which the same plant uses raoi-e than one of
these modes of promoting the dispersion of its seeds, still there are
some such instances. Thus in the common burdock the seeds have
a pappus, while the whole flower-head is provided with hooks which
readily attach themselves to any passing animal. Asterothrix, as Hil-
debrand has pointed out, has three provisions for dispersion ; it has a
hollow appendage, a pappus, and a rough surface.

But perhaps it will be said that I have picked out special cases ;
that others could have been selected, which would not bear out, or
perhaps would even negative, the inferences which have been indi-
cated ; that I have put the cart before the horse ; that the ash-fruit
has not a wing in order that it may be carried by the wind, or the
burdock hooks that the heads may be transported by animals, but
that, happening to have wings and hooks, these seeds are thus trans-
ported. Now, doubtless there are many jjoints connected with seed.>-:



Oy FRUITS AND SEEDS.



357



which are still unexplained ; in fact, it is because this is so that I
was anxious to direct attention to the subject. Still I believe the
ireneral explanations which have been given by botanists will stand
any test.

Let us take, for instance, seeds formed on the same type as that of
the ash — heavy fruits, with a long wing, known to botanists as a sa-



'A







Fic. 15— a. Harpagoputtos proclmu



size); 6, Martysia proboscidea (natural



size).

uiara. Xow, such a fruit would be of little use to low herbs, which,
however, are so numerous. If the wing was accidental, if it was not
developed to serve as a means of dispersion, it would be as likely to
occur on low plants and shrubs as on trees. Let us, then, consider on
what kind of plants these fruits are found. They occur on the ash,
maple, sycamore, hornbeam, pines, firs, and elm ; while the lime, as



358 THE POPULAR SCIENCE MONTHLY.

Ave have seen, has also a leaf attached to the fruits, which answers the
same purposes. Seeds of this character therefoi'e occur on a large pro-
portion of our forest-trees, and on them alone. But more than this :
I have taken one or two of the most accessible works in which seeds
are figured, for instance, Gartner's "De Fructibus et Serainibus," Le
Maout and Decaisne's (Hooker's translation) " Descriptive and Ana-
lytical Botany," and Baillon's " Ilistoire des Plantes." I find thirty
genera, belonging to twenty-one different natural orders, figured as
having seeds or fruits of this form. They are all trees or climl)ing
shrubs, not one being a low herb.

Let us take another case, that of the plants in which the disjiersion
of the seeds is effected by means of hooks. Now, if the presence of
these hooks was, so to say, accidental, and the dispersion merely a re-
sult, we should naturally ex23ect to find some species with hooks in all
classes of plants. They would occur, for instance, among trees and
on water-plants. On the other hand, if they are developed that they
might adhere to the skin of quadrupeds, then, having reference to the
habits and size of our British mammals, it would be no advantage for
a tree or for a water-plant to bear hooked seeds. Now, what are the
facts ? There are about thirty English species in which the dispersion
of the seeds is effected by means of hooks, but not one of these is
aquatic, nor is one of them more than four feet high. Nay, I might
carry the thing further. We have a number of minute plants, which
lie below the level at which seeds would be likely to be entangled in
fur. Now, none of these, again, have hooked seeds or fruits. It
would also seem, as Hildebrand has suggested, that in point of time,
also, the appearance of the families of plants in which the fruits or
seeds are provided with hooks coincided with that of the land mam-
malia.

Again, let us look at it from another point of view. Let us take
our common forest-trees, shrubs, and tall, climbing plants — not, of
course, a natural or botanical group, for they belong to a number of
different orders, but a group characterized by attaining to a height of
say over eight feet. We will in some cases only count genera ; that is
to say, we will count all the willows, for instance, as one. These ti-ees
and shrubs are plants with which you are all familiar, and are about
thirty-three in number. Now, of these thirty-three no less than eigh-
teen have edible fruits or seeds, such as the plum, apple, arbutus,
holly, hazel, beech, and rose. Three have seeds which are provided
with feathery hairs ; and all the rest, namely, the lime, maple, ash,
sycamore, elm, hop, birch, hornbeam, pine, and fir, are provided with
a wing. Moreover, as will be seen by the following table, the lower
trees and shrubs, such as the cornel. Guelder rose, rose, thorn, privet,
elder, yew, and holly, have generally edible berries, much eaten by
birds. The winged seeds or fruits characterize the great forest-
trees.



ox FRUITS AXD SEEDS.



359



:ks, siikl'bs, and climbing shrubs native or naturalizkd in

BRITAIN.





Seed or Frcit.


Edible.


Hairy.


Winged. Hooked.








-




X


Lime ( T'dia Europcea)

! Maple ( \ccr)


i Spindle-trce [Euonymus)

1 Buckthorn (Jihatnnn.s)




1 Rose (Rosa)

; Apple (PyrM.s)

1 Hawthorn ( Ci'cticenux) . . .


X

X 1

X 1


; Medlar (J/«/«7?«)

Ivy {Hedera)

Cornel iCornus) , .


X XX XXXXX




, Elder {Sambucm)

Guelder rose ( Viburnum)

Honeysuckle (Loniccra).

Arbutus (Ayhult(s)

Holly (//«)

Ash {Fraxinus)

Privet (Ligustrum)

Elm {Ulmus)

Hop {llumidus)

Alder (.!/«?«)


X
X




Hirch {Bdula)


X


X


Nut {Corylus)




Oak {QuercHs)




X
X




Willow (&(//j;)




Poplar {Popuhis)

Pine (Pinus)


' Fir (Abies)

Yew{Taxus)


X


1 X





Or lot us take one natural order. That of the roses is particularly
interesting. In the genus Geum the fruit is provided with hooks ; in
iJrijas it terminates in a long feathered awn, like that of Clematis.
On the other hand, several genera have edible fruits ; but it is curi-
ous that the part of a plant which becomes fleshy, and thus tempting
to animals, differs considerably in the different genera. In the black-
berry, for instance, and in the raspberry, the carpels constitute the
edible portion. When we eat a raspberry we strip them off and leave
the receptacle behind ; while in the strawberry the receptacle consti-
tutes the edible portion ; the carpels are small, hard, and closely sur-
round the seeds. In these genera the sepals are situated below the
fruit. In the rose, on the contrary, it is the peduncle that is swollen
:ind inverted, so as to form a hollow cup, in the interior of which the
carpels are situated. Here you will remember that the sepals are situ-
:ited above, not below, the fruit. Again, in the pear and apple, it is



3 bo



THE POPULAR SCIENCE MONTHLY.



the ovary which constitutes the edible part of the fruit, and in which
the pips are imbedded. At first sight, the fruit of the mulberry —
which, however, belongs to a different family — closely resembles that
of the blackberry. In the mulberry, however, it is the sepals which
becomes fleshy and sweet.

The next point is that seeds should be in a spot suitable for their
growth. In most cases the seed lies on the ground, into which it then
pushes its little rootlet. In plants, however, which 'live on trees, the
case is not so simple, and we meet some curious contrivances. Thus,
the mistletoe, as we all know, is parasitic on trees. The fruits are
eaten by birds, and the droppings often, therefore, fall on the boughs ;
but if the seed were like that of most other plants it would soon fall to
the ground and consequently perish. Almost alone among English
plants it is extremely sticky and thus adheres to the bark.




MxzoDEKDROx. (After Hooker.)



I have already alluded to an allied genus, Arceuthobium, parasitic
on junipers, which throws its seeds to a distance of several feet. These
also are very viscid, or, to speak more correctly, are imbedded in a
very viscid mucilage, so that if they come in contact with the bai'k of
a neighboring tree they stick to it.



ON FRUITS AXD SEEDS.



361



Another interesting genus, again of the same family, is Myzoden-
dron (Fig. 16), a Fuegian species, described by Sir Joseph Hooker,
and parasitic on the beech. Here the seed is not sticky, but is provided
with four flattened, flexible appendages. These catch the wind, and
thus carry the seed from one tree to another. As soon, however, as
they touch any little bough, the arras twist round it and there anchor
the seed.

In many epiphytes the seeds are extremely numerous and minute.
Their great numbers increase the chance that the wind may waft some
of them to the trees on which they grow ; and as they are then fully
supplied with nourishment they do not require to carry any store with
them. Moreover, their minute size is an advantage, as they are car-
ried into any little chink or cranny in the bark, while a larger or
heavier seed, even if borne against a suitable tree, would be more




Fig. 17.— Cakdamine ciienopodifolia. a a, ordinary po;lai ; b, subterranean pods



likely to drop off. In the genus Xeumannia, the small seed is pro-
iluced at each end into a long filament which must materially increase
its chances of adhering to a suitable tree.

Even among terrestrial species there are not a few cases in which



362



THE POPULAR SCIEXCE MONTHLY



]>lants are not contented simply to leave their seeds on the surface of
the soil, hut actually sow them in the ground.

Thus in Trifolium siihterraneum, one of our rarer English clovers,
only a few of the florets become perfect flowers, the others form a
rigid, pointed head, which at first is turned upward, and, as their ends
are close together, constitute a sort of spike. At first, I say, the flower-
heads point upward like those of other clovers, but, as soon as the
florets are fertilized, the flower-stalks bend over and grow downward,
forcing the flower-head into the ground, an operation much facilitated
by the peculiar construction and arrangement of the imperfect florets.
The florets are, as Darwin has shoAvn, no mere passive instruments.
So soon as the flower-head is in the ground they begin, commencing
from the outside, to bend themselves toward the peduncle, the result
of which, of course, is to drag the flower-head farther and farther into
the ground. In most clovers each floret produces a little pod. This




w



Fig. 18.— YiciA amphicarpa. a a, ordinary pods ; b b, Bubterrancan pods.



would in the present species be useless, or even injurious ; many young
plants growing in one place would jostle and starve one another.
Hence we see another obvious advantage in the fact that only a few
florets perfect their seeds.



ox FRUITS AND SEEDS.



363



I have already alluded to our cardamines, the pods of wbicli open
flastically and throw their seed some distance. A Brazilian species,
C . ehenopodifoUa (Fig. IT), besides the usual long pods (Fig. 17, aa\
produces also short, pointed ones (Fig. IT, b b), which it buries in the
ground.

Arachis hypogcea is the ground-nut of the West Indies. The
Hower is yellow and resembles that of a pea, but has an elongated
calyx, at the base of which, close to the stem, is the ovary. After the
flower has faded, the young pod, which is oval, pointed, and very
minute, is carried forward by the growth of the stalk, which becomes
two or three inches long and curves downward, so as generally to force
the pod into tiie ground. If it fails in this, the pod does not develop,
but soon perishes ; on the other hand, as soon as it is underground,
the pod begins to grow and develops two large seeds.

In Vicia ampMcarpa (Fig. 18), a south European species of vetch,




Fig. 19.— Latiitrcs amphicarpos. (After Sowerby.) a, ordinary pods ; h. subterranean pods.



there are two kinds of pods. One of the ordinary form and habit {at),
the other (/>) oval, pale, containing only two seeds, borne on under-
ground stems, and produced by flowers which have no corolla.



364



THE POPULAR SCIEXCE MONTHLY.



Again, a species of the allied genus Z,atJnjnis (Fig. 19), L. arnpJii-
carjjos, affords us another ease of the same phenomenon.

Other species possessing the same faculty of burying their seeds
are Okenia hypogwa, several species of Commelyna, and of Arnphi-
carpc^a, Voandzeia suhterranea, Scropjhularia arguta, etc. ; a'nd it is
very remarkable that these species are by no means nearly related, but
belong to distinct families, namely, the Cruciferce, Legumi7ios(e, Com-
melyriacetx^ Jlokicece, and Scropkulariacece.

Moreover, it is interesting that in X. amphicarpos, as in Vicia
amp/ii'carjMt and Cardamine ehenojwdifoUum, the subterranean pods
differ from the usual and aerial form in being shorter and containing
fewer seeds. The reason of this is, I think, obvious. In the ordinary
pods the number of seeds of course increases the chance that some will
find a suitable place. On the other hand, the subterranean ones are
carefully sown, as it were, by the plant itself. Several seeds together
would only jostle one another, and it is therefore better that one or
two only should be produced.

In the Erodlums, or cranesbills, the fruit is a capsule which open
elastically, in some species throwing the seeds to some
;.\ little distance. The seeds themselves are more or less

spindle-shaped, hairy, and produced into a twisted hairy
awn as shown in Fig. 20, representing a seed of -£". glaxi-
copjhyllum. The number of spiral turns in the awn de-
pends upon the amount of moisture ; and the seed may
thus be made into a very delicate hygrometer, for, if it
be fixed in an upright position, the awn twists or un-
twists according to the degree of moisture, and its
extremity thus may be so arranged as to move up and
down like a needle on a register. It is also affected by
heat. Now, if the awn were fixed instead of the seed,
it is obvious that, during the process of untwisting, the
seed itself would be pressed downward, and, as M. Roux
has shown, this mechanism thus serves actually to bury
the seed. His observations were made on an allied
species, Erodium ciconhan, which he chose on account
of its size. He found that, if a seed of this plant is laid
on the ground, it remains quiet as long as it is dry ; but
as soon as it is moistened — i. e., as soon as the earth be-
F10-. 20.— Erodicm comes in a condition to permit growth — the outer side
(After Sweet.) of the awn contracts, and the hairs surroundmg the
seed commence to move outward, the result of which
is gradually to raise the seed into an upright position with its point
on the soil. The awn then commences to unroll, and consequently to
elongate itself upward, and it is obvious that, as it is covered Avith
reversed hairs, it will probably press against some blade of grass or
other obstacle, which will prevent its moving up, and will therefore




ox FRUITS AXD SEEDS.



365



tend to drive the seed into the ground. If, then, the air becomes



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