which we admired just now; and, black as yew against the blue sky
and white cloud, the plumes of one Palmiste, who has climbed toward
the light, it may be for centuries, through the green cloud; and
now, weary and yet triumphant, rests her dark head among the bright
foliage of a Ceiba, and feeds unhindered on the sun.
There, take your tired eyes down again; and turn them right or left,
where you will, to see the same scene, and yet never the same. New
forms, new combinations; wealth of creative Genius--let us use the
wise old word in its true sense--incomprehensible by the human
intellect or the human eye, even as He is who made it all, whose
garment, or rather whose speech, it is.
MILK-SAP PLANTS
--M. J. SCHLEIDEN
All the plants which count caoutchouc among their products belong to
the torrid zone. A. von Humboldt, in his _Ideas of a Geography of
Plants_, remarked that the plants yielding _milky_ juices multiply as
we approach the tropics. This _milky juice_ of plants it is which
contains the peculiar elastic substance. The tropical heat seems
to exert a distinct influence in its perfect formation, for it has
been remarked that the same plants which under the equator yield
abundance of caoutchouc contain instead, with us, even in hothouses,
a substance which resembles the bird-lime obtained from our native
mistletoe.
Who among my readers has not seen our indigenous wolf’s-milk
or spurge, the white milky juice of which popular superstition
recommends as a remedy against warts? Who has not in youth at least
become acquainted with the celandine, from the broken stalk and leaf
of which a bright orange-colored juice runs out? Who has not observed
that the lettuce, when it has run up to flower, ejects a milk-white
fluid at the slightest touch? But the occurrence of milky juices in
plants is not limited to these few. The vegetable world presents to
us most useful as well as poisonous matters in this milky sap, and I
will content myself at present with recalling to recollection opium,
the dried milky juice of our large garden poppy.
A great number of plants, which principally belong to three great
families, namely, the Spurges, the Apocynoceæ, and the Nettle plants,
are distinguished by a peculiar anatomical structure. In their bark,
and also partly in their pith, we find a quantity of long, variously
curved and branched tubes, which are not unlike the veins of animals.
In these tubes we find a thick juice of the consistence of very rich
milk, whence it is called milk-sap. Its color is usually milk-white,
but yellow, red, and, very rarely, blue milk-saps are met with,
but more frequently still they are wholly colorless. Like animal
milk, this juice consists of a colorless fluid and small globules.
The composition displays the most varied constituents, and upon the
variation of quantity and modes of mixture of these matters depend
the abundant varieties of this juice. All contain more or less
caoutchouc, which occurs in the form of little globules. These are
prevented from coalescing by an albuminous substance, in the same
way as are the butter globules in milk. Exactly like the cream (the
butter) in milk, the caoutchouc globules rise to the surface of the
milk-sap of plants when left to stand, here form a cream, and can
not, any more than butter, be separated again into their distinct
globules.
All those three great families which are distinguished by their
abundance of milk-sap, although differing very widely botanically,
exhibit some most remarkable agreements through the nature of their
milk-sap.
The spurges or Euphorbiaceæ constitute the most important group in
reference to the amount of caoutchouc contained. From the Port of
Para in South America, from Guiana, and the neighboring states, an
incredible quantity of India-rubber is shipped for Europe, and this
is principally obtained from a large tree growing in those regions,
called the Siphonia elastica. That beautiful tree, the Siphonia, is
about sixty feet high, and has a smooth brownish-gray bark, in which
the Indians make long and deep incisions down to the wood, from
whence the white juice then abundantly flows forth.
Many other plants of this group contain caoutchouc, but from none is
it so easy to obtain in large quantity. Though the sap of Siphonia is
at least harmless, though the juice of the Tabayba dolce (Euphorbia
balsamifera) is even similar to sweet milk and, thickened into a
jelly, eaten as a delicacy by the inhabitants of the Canary Islands,
as Leopold von Buch relates in his interesting description of the
Canaries; yet most of the plants of this group are to be counted
among the suspicious, or even most actively poisonous, on account
of this very juice. And yet, strangely enough, they also furnish
a most wholesome food, which we have scarcely anything to compare
with. Throughout all the hotter part of America the culture of the
mandioc-root (Jatropha Manihot) is one of the most important branches
of husbandry. The native savages and the Europeans, the black slave
and free man of color alike substitute for our white bread and rice
the tapioca and the Mandiocca farinha, or Cassava-meal, and the
cakes prepared from it (_pan de tierra caliente_ of the Mexicans).
The sweet yucca (Yuca dulce), which is the name applied there to the
mandioc plant, must be distinguished from the sour or bitter kind
(Yuca amara). The former, which is therefore cultivated with great
care, may be eaten at once without danger; while the latter, eaten
fresh, is an active poison. They serve the uncivilized son of the
South American tropics for food.
The sated savage saunters round to seek a new sleeping-place, but
woe to him! inadvertently he has prepared his couch beneath the
dreadful manchineel (Hippomane Mancinella), and in a sudden shower
the rain drips from its leaves upon him. In frightful pain he wakes
up, covered with blisters and ulcers, and if he escapes with life,
he is at least the richer of a fearful experience of the poisonous
properties of the Euphorbiaceæ. But this will seldom happen to a
native; the manchineel is avoided in America with the same mysterious
and almost superstitious awe as the fabulous poison-tree in Java.
Happily, the trumpet-tree (Bignonia leucoxylon), the sap of which
is the surest antidote against the manchineel, usually rears its
beautiful purple blossoms close at hand, the constant companion of
that dangerous Euphorbiacean.
The planter of the Cape strews over pieces of flesh the pounded fruit
of a plant that grows there (Hyænanche globosa), and lays them as an
infallible poison for the hyena. The wild inhabitants of southern
Africa, according to Bruce, poison their arrows with a spurge
(Euphorbia caput Medusæ). Virey states that the Ethiopians make a
similar application of others (Euphorbia heptagona, Euphorbia virosa,
Euphorbia cereiformis), while the savages of the most southern part
of America use the sap of a third (Euphorbia cotinifolia). Nay, even
our seemingly so innocent box, which also belongs to this family,
is so injurious that in places in Persia, where it much abounds, no
camels can be kept, because it is impossible to prevent their feeding
on this plant, which is deadly to them. I can not take leave of this
family without mentioning a remarkable phenomenon, reported to us by
Martius, in that work so full of information, his _Travels Through
Brazil_. A spurge grows there (Euphorbia phosphorea), the milk of
which, when it flows forth from the stem in the dark, hot summer
nights, emits a bright phosphoric light.
While the family just alluded to, the blossoms being generally
insignificant, attract the attention of our horticulturists almost
solely through their strange forms, which, in some of them, approach
to those of the cactus plants, the family of the Apocynaceæ is,
on the contrary, a rich ornament of our gardens and hothouses,
on account of the wonderful beauty of its blossoms, and is often
still more attractive from the remarkable structure of the flowers,
and the aberrant, also cactus-like form of the plant itself. What
lover of flowers knows not the splendid blossom of the species of
Carissa, Allamanda, Thevetia, Cerbera, Plumieria, Vinca, Nervium,
and Gelsemium; the strange stalk and toad-colored, ill-smelling
flowers of the Stapelia? But this family is not less interesting in
other respects. The best caoutchouc at present known, that from Pulo
Penang, comes from a plant of this family (Cynanchum ovalifolium).
Also that from Sumatra (Urceola elastica), from Madagascar (Vahea
gummifera), a part of the Brazilian Collophora utilis and Hancornia
speciosa, and the East Indian Willughbeia edulis are obtained from
plants which belong to the group of Apocynaceæ.
Most strangely, this family also, as well as the following and
last, exhibits the peculiar phenomenon which was described in the
first-named, the Euphorbiaceæ, namely, that the milk-sap is in some
species rich in India-rubber, in others it is tempered into a clear,
agreeably smelling and wholesome milk, while in certain others, on
the contrary, this fluid grows, step by step, through successively
increasing quantity of noxious matter to a most dreadful poison.
In the forests of British Guiana grows a tree which the natives
call Hya-Hya (Tabernæmontana utilis). Its bark and pith are so rich
in milk that an only moderate-sized stem, which Arnott and his
companions felled on the bank of a large forest brook, in the course
of an hour colored the water quite white and milky. This milk is
perfectly harmless, of a pleasant flavor, and is taken by the savages
as a refreshing drink. Still more pleasant must be the taste of the
milk of the Ceylon cow-tree, the Kiriaghuma (Gymneura lactiferum),
which, according to Burmann’s narrative, the Cingalese use exactly as
we do milk.
Dreadful, on the contrary, is the action of the terrible wourali
poison, which the inhabitants of the banks of the Orinoco concoct
with mystic conjurations, the chief ingredients of which are
furnished by the juice of a plant belonging here (Echites suberecta)
and the bark of another, likewise an Apocynaceous tree, Strychnos
guinanensis and Strychnos toxifera. The North Americans also use an
Apocynaceous plant (Gonolobium macrophyllum) to poison their arrows;
and Mungo Park related the like of the Mandingoes of the Niger
(according to him it is a species of Echites).
Many allied plants are among the most active poisons (Cerbera
Thevetia and Cerbera Ahovai), and the seeds of this group, in
particular, are almost more remarkable for their deadliness than
those of the foregoing, for two of the most violent vegetable
poisons, strychnine and brucine, occur in them. Some of our most
active medicinal substances are especially known on this account; for
instance, the St. Ignatius’s beans (Ignatia amara from Manila), and
the Nux vomica (Strychnos nux Vomica), distributed throughout the
tropics.
It would not be difficult to make some of the more important
characters of the two families I have mentioned so clear, even to a
person unacquainted with botany, that he would be enabled readily to
distinguish any plant belonging to them. Very different is it with
the following, the last group, the Jussieuan family of nettle-plants,
or Urticaceæ. The plants belonging to this vary in the most striking
manner in their external forms, from the smallest, most insignificant
weeds, like our common pellitory of the wall and our nettles, to
vast and stately trees like the breadfruits (Artocarpus integrifolia
and incisa), which, with their wide-stretched branches and broad,
beautifully formed leaves, overshadow the huts of the South Sea
Islander, who lives upon their savory fruit. As in the family of
the spurges, only some few plants bestow in their seed a pleasant
nut-like kernel (as Aleurites triloba in the Moluccas, Conceveiba
guianensis in South America); as in the Apocynaceous group, several
trees afford cooling, juicy, and therefore highly valued fruits
to the inhabitants of hot regions (Carissa Carandas in the East
Indies, Carissa edulis in Arabia, etc.), so the family of the
Urticaceæ includes the strangest multiplicity of fructifications. The
little oil grains of the hemp, the green grape-like bunches which
gracefully adorn the slender twining hop, the aromatic mulberry,
the sweet fig, the useful bread-fruit, all those so various forms
belong to one group of plants, and the botanist traces in all the
same fundamental structure, however incongruous these manifold shapes
may appear to the eye of the uninitiated. One peculiarity alone
extends without exception throughout all the species of this large
order, namely, the presence of fine but strong bass-fibres in the
bark. The German name for muslin, Nessel-tuch (nettle-cloth), denotes
the source from whence the fibre of which it is made was originally
obtained (Urtica cannabina), and the skilful industry of the gentle
Tahitan prepares the most delicate stuff, without spinning-wheel
or loom, from the fine white bass of the auté of paper-mulberry
(Broussonetia papyrifera).
An elegant tree, allied to the last, the Holquahuitl of the Mexicans,
or Ule di Papantla of the Spaniards (Castilloa elastica Deppe),
furnishes the caoutchouc of New Spain, and the inconceivable
quantities of this substance which are brought to our ports from the
East Indies are collected in great part from the venerable fig-trees
in which that Asiatic tropical world is so rich. On a trunk of giant
girth, but seldom more than fifteen feet high, rests the enormous
crown of the banyan, or holy fig (Ficus religiosa); the branches
often run a hundred feet horizontally out from the trunk, sending
down to the ground, at various intervals, long straight roots, which
quickly penetrate and take firm hold, thus becoming props to the long
branches. These wonderful trees, each one resembling a small wood,
are dedicated to the god Fo, and the helpless, lazy Bonze builds his
hut, not unlike a bird-cage, in its branches, in which he passes the
day, sometimes asleep, sometimes dreaming in contemplative indolence
in the pleasant cool shade. These great fig-trees (Ficus religiosa,
indica, benjaminea, elastica) have sweet fruits, and their milk-sap
contains the interesting caoutchouc. Some of these plants also yield
a harmless juice. By far the most remarkable in this respect is
the Palo de Vacca or Arbol de Leche, the cow-tree of South America
(Galactodendron utile), which was first made known to us by Alexander
von Humboldt. When a tolerably large incision is made into the trunk
of this tree, a white, oily, fragrant, and sweet fluid, very similar
to animal milk, flows out in sufficient quantity to refresh and
satisfy the hunger of several persons.
A striking contrast to this is afforded by the properties of other
nettle-plants. One is tempted to call them the serpents of the
vegetable kingdom; and the parallel is not difficult to carry out.
The similarity between the instruments with which both produce and
poison their wounds is very remarkable. The snakes have in the front
of the upper jaw two long, thin, somewhat curved teeth, which are
perforated lengthwise by a minute canal, which opens in front at the
sharp point. These teeth are not fixed firmly in the jaw like the
others, but movable, like, but in a less degree, the claws of a cat.
Beneath each tooth, in a cavity in the jaw, lies a little gland, in
which the poison is prepared, and the excretory duct of this gland
runs through the canal in the tooth, and opens at its apex. When
the animal bites, the resistance of the bitten body pushes back the
tooth, so that it presses upon the gland, which squeezes out of it
the deadly fluid into the wound. If we examine, now, the hairs on the
leaf of the nettle, we find a wonderful agreement. The stinging hair
consists of a single cell, terminating above in a little knob. Below,
it expands into a small sac, which contains the irritating juice.
The slightest touch breaks off the brittle point with the little
knob, the canal of the hair is thus opened, and it penetrates any
soft substance; in consequence of the pressure which the resistance
to its entry exerts upon the sac, a portion of the poisonous juice
is ejected out into the wound. The poisons of our native nettles and
snakes are not of much consequence, but the nearer we approach the
tropics, the more frequent and more deadly they both become. Where
the glowing Indian sun ripens the poison of the fearful spectacle
snake, there grow the most dangerous nettles.
Every one among us has felt the slight but irritating sting of the
nettle which it produces by its slender poisonous hair, but we have
no notion of the torture which its near allies (Urtica stimulaus,
Urtica crenulata) produce in the East Indies. A gentle touch suffices
to cause the arm to swell up with the most frightful pain, and the
suffering lasts for weeks; nay, a species growing in Timor (Urlica
urentissima) is called by the natives Daoun Setan (devil’s leaf),
because the pain lasts for years, and often even death can only be
avoided by the amputation of the injured limb.
We do, indeed, find many violent poisons in this family, and even
some species of fig are included among the most dangerous plants
(Ficus toxicaria), but it is not worth while to linger among those
of lesser importance. The tales recounted of the Upas and the
Poison-valley mingle almost like a dark and gloomy legend in our
knowledge of the East Indian islands.
In the Sixteenth Century stories circulated about the macassar
poison-tree of the Celebes; and physicians and naturalists came
gradually to tell of the action of the poison, the descriptions of
which had become so terrible that if the smallest quantity entered
the blood, not only immediate death resulted, but its action was so
fearfully destructive that within half an hour afterward the flesh
fell from the bones. From Rumph we learned that the poison-tree is
also met with in Sumatra, Borneo, and Bali, as well as in Celebes.
But the Dutch surgeon, Försch, first spread the wild tales of the
poison-tree of Java about the end of the Eighteenth Century.
Two very different trees grow in those little visited primeval
forests of Java. All the paths leading to them are closed and
watched, like those leading to the gates of the Holy of Holies.
With fire and axe must the road be made through the impenetrably
interwoven mass of lianes, the paullinias, with their clusters of
great scarlet blossoms several feet long, the cissi or wild vines,
on the widespread creeping roots of which thrives the gigantic
flower of the Rafflesia Arnoldi. Palms, with spines and thorns,
rush-like plants with cutting leaves, wounding like knives, warn the
intruder back by their attacks, and in every part of the thicket
threaten the fearful nettles formerly mentioned. Great black ants,
whose painful bite tortures the wanderer, and countless swarms of
tormenting insects pursue him. Are these obstacles overcome? Yet
follow the dense bundles of bamboo stems, as thick as a man’s arm,
and often fifty feet high, the firm glassy bark of which repels even
the axe. At last the way is opened and the majestic aisles of the
true primeval forest now display themselves. Gigantic trunks of the
bread-fruit, of the iron-like teak (Tectona grandis), of Leguminosæ,
with their beautiful blossoms, of Barringtonias, figs, and bays, form
the columns which support the massive green vault. From branch to
branch leap lively troops of apes, provoking the wanderer by throwing
fruit upon him. From a moss-clad rock the melancholy orang-outang
raises himself gravely on his staff, and wanders into deeper
thickets. All is full of animal life; a strong contrast to the desert
and silent character of many of the primeval forests of America. Here
a twining, climbing shrub, with a trunk as thick as one’s arm, coils
round the columns of the dome, overpassing the loftiest trees, often
quite simple and unbranched for a length of a hundred feet from the
root, but curved and winding in the most varied forms. The large,
shining green leaves alternate with the long and stout tendrils
with which it takes firm hold, and greenish-white heads of pleasant
smelling flowers hang pendent from it. This plant, belonging to the
Apocynaceæ, is the Tjettek of the natives (Strychnos Tieute), from
the roots of which the dreadful Upas Radia, or Sovereign Poison, is
concocted. A slight wound from a weapon poisoned with this--a little
arrow made of hard wood, and shot from the blow-tube, as by the South
Americans--makes the tiger tremble, stand motionless a minute, then
fall as though seized with vertigo, and die in brief but violent
convulsions. The shrub itself is harmless, and he whose skin may
have been touched with its juice need fear no consequences. As we
go forward, we meet with a beautiful slender stem, which overtops
the neighboring plants. Perfectly cylindrical, it rises sixty or
eighty feet, smooth and without a branch, and bears an elegant
hemispherical crown, which proudly looks down on the more humble
growths around, and the many climbers struggling up its stem. Woe to
him who heedlessly should touch the milk-sap that flows abundantly
from its easily wounded bark. Large blisters, painful ulcers, like
those produced by our poisonous sumach, only more dangerous, are the
inevitable consequences. This is the Antiar of the Javanese, the
Pohon Upas (signifying poison-tree) of the Malays, the Ipo of Celebes
and the Philippines (Antiaris toxicaria).
NUTS
--GRANT ALLEN
On the wooded slope where the park shelves slowly toward the Bourne
Brook, the ground to-day (October) is thickly strewn in many places
with the sharp, prickly husks and small, barren, angular nutlets
of the beautiful Spanish chestnuts. They are not truly indigenous
to Britain, these noble spreading forest trees, though they have
been planted so long in our pleasure grounds and lawns that we have
got to look upon them almost as naturalized British subjects; and
the climate, though it suits the leaves and wood well enough, is
not sufficiently kindly to ripen the fruits in due season; they
are almost always mere empty, shriveled shells here in England, so
that we have to import seed for sowing from the mountain regions
of Southern Europe. There we have all seen them growing in their
own wild luxuriance on the lower escarpments of the Alps or the
Apennines, and bringing forth fertile nuts sufficient to feed half
the teeming population of the Lombard plain in seasons of scarcity.
Side by side with them in the park here, the boys are impartially
shying sticks at the very similar, though wholly unrelated, clusters
of the common horse-chestnuts, which, in spite of their close
external likeness, belong in reality to a totally different and much
more restricted family. The true chestnut is a catkin bearer, a near
relation of the English oak, as one might almost guess at sight from
its foliage and habit; the horse-chestnut is a member of a tribe
unrepresented in our native English flora, but not very unlike the
maples and sycamores in its principal characters. It is interesting
to note how in the case of these two wholly different and originally
dissimilar trees similarity of circumstances has at last produced
such great similarity of adaptive peculiarities.