Chapter XII: Part 12

The _Cayos Flamenco_, _Bonito_, _de Diego Perez_, and _de Piedras_,
are coral islands, rising only from 8 to 15 inches above the level of
the sea. The upper edge of the reef does not consist merely of dead
polyp-trunks, but is rather formed of a true conglomerate, in which
angular pieces of coral, lying in various directions, are embedded in
a cement composed of granules of quartz. In Cayo de Piedras I saw such
embedded masses of coral, some of them measuring upwards of three
cubic feet. Several of the West Indian smaller coral islands have
fresh water, a phenomenon which merits a careful investigation
wherever it occurs (as for instance near Radak in the South Sea),[KZ]
since it has sometimes been ascribed to hydrostatic pressure, acting
from a distant coast (as in Venice, and in the Bay of Xagua, east of
Batabano), and sometimes to the filtration of rain-water.[LA]

The living gelatinous covering of the calcareous fabric of the
coral-trunks attracts fishes and even turtles in search of food. In
the time of Columbus the now desolate district of the Jardines del Rey
was animated by a singular branch of industry pursued by the
inhabitants of the sea-coasts of Cuba, who availed themselves of a
little fish, the Remora, or sucking-fish (the so-called Ship-holder),
probably the Echeneis naucrates, for catching turtles. A long and
strong line, made of the fibres of the palm, was attached to the tail
of the fish. The Remora (called in Spanish _Reves_, or reversed,
because at first sight the back and abdomen might easily be mistaken
for each other), attaches itself by suction to the turtle through the
indented and moveable cartilaginous plates of the upper shell that
covers the head. The Remora, says Columbus, would rather let itself be
torn to pieces than relinquish its prey, and the little fish and the
turtle are thus drawn out of the water together. “Nostrates,” says
Martin Anghiera, the learned secretary of Charles V, “piscem Reversum
appellant, quod versus venatur. Non aliter ac nos canibus gallicis per
æquora campi lepores insectamur, illi (incolæ Cubæ insulæ) venatorio
pisce pisces alios capiebant.”[LB] We learn from Dampier and
Commerson, that this artifice of employing a sucking-fish to catch
other fishes is very common on the eastern coasts of Africa, near Cape
Natal and Mozambique, as well as on the island of Madagascar.[LC] An
acquaintance with the habits of animals, and the same necessities,
lead to similar artifices and modes of capture amongst tribes having
no connection with one another.

Although, as we have already remarked, the actual seat of the
Lithophytes who build calcareous walls, lies within a zone extending
from 22 to 24 degrees on either side of the equator, yet coral-reefs,
favoured, it is supposed, by the warm Gulf Stream, are met with around
the Bermudas in 32° 23′ lat., and these have been admirably described
by Lieutenant Nelson.[LD] In the southern hemisphere corals
(Millepores and Cellepores) are found singly as far as Chiloe and even
to the Chonos-Archipelago and Tierra del Fuego, in 53° lat., while
Retepores have even been found as far as 72½° lat.

Since Captain Cook’s second voyage, the hypothesis advanced by him as
well as by Reinhold and George Forster, that the flat coral islands of
the South Pacific have been built up by living agents from the depths
of the sea’s bottom, has found numerous advocates. The distinguished
naturalists Quoy and Gaimard, who accompanied Captain Freycinet on his
voyage of circumnavigation in the frigate “Uranie,” were the first who
expressed themselves, in 1823, with much freedom against the views
advanced by the two Forsters (father and son), by Flinders, and
Péron.[LE] “In directing the attention of naturalists to
coral-animalcules,” they say, “we hope to be able to prove that all
which has been hitherto affirmed or believed up to the present time,
regarding the immense structures they are capable of raising, is for
the most part inexact, and in all cases very greatly exaggerated. We
are rather of opinion that coral-animalcules, instead of rearing
perpendicular walls from the depths of the Ocean, only form strata or
incrustrations of some few toises in thickness.” Quoy and Gaimard (p.
289) have also expressed an opinion, that Atolls (coral walls
inclosing a lagoon) owe their origin to submarine volcanic craters.
They have undoubtedly underrated the depth at which animals who
construct coral-reefs (as for example the Astræa) can exist, as they
place the extreme limits at from 26 to 32 feet below the level of the
sea. Charles Darwin, a naturalist, who has known how to enhance the
value of his own observations by a comparison with those of others in
many parts of the world, places the region of living coral-animals at
a depth of 20 or 30 fathoms,[LF] which corresponds with that in which
Professor Edward Forbes found the greatest number of corals in the
Ægean Sea. This is Professor Forbes’s fourth region of marine-animals,
as given in his ingenious memoir on the _Provinces of Depth_, and the
geographical distribution of Mollusca at perpendicular distances from
the surface.[LG] It would appear, however, that the depth at which
corals live is very different in the different species, especially in
the more delicate ones which do not form such considerable structures.

Sir James Ross, in his Antarctic expedition, brought up corals from a
great depth with the lead; and these he remitted for accurate
examination to Mr. Stokes and Professor Forbes. Westward of Victoria
Land, in the neighbourhood of the Coulman Island, in 72° 31′ south
lat., and at a depth of 270 fathoms, Retepora cellulosa, a Hornera,
and Prymnoa Rossii. (the latter very similar to a species common to
the coasts of Norway,) were found alive and in a perfectly fresh
condition.[LH] In the far north too, the Greenland _Umbellaria
Grœnlandica_ has been brought up alive by whale fishers from a depth
of 236 fathoms.[LI] The same relation between species and locality is
met with among sponges, which however are now regarded as belonging
more to plants than to zoophytes. On the shores of Asia Minor, the
common marine sponge is brought up from depths varying from 5 to 36
fathoms, although one very small species of the same genus is only
found at a depth of at least 180 fathoms.[LJ] It is difficult to
divine what hinders the Astræas, Madrepores, Mæandrinas, and the whole
group of tropical phyto-corals, which are capable of constructing
large cellular calcareous walls, from living in very deep strata of
water. The decrease of temperature is very gradual, the diminution of
light nearly the same, and the existence of numerous Infusoria at
great depths of the Ocean proves that there cannot here be any
deficiency of food for polyps.

In opposition to the hitherto generally adopted opinion respecting the
absence of all organisms and living creatures in the Dead Sea, it is
worthy of notice that my friend and fellow-labourer, M. Valenciennes,
has received, through the Marquis Charles de l’Escalopier, and through
the French Consul Botta, beautiful specimens of Porites elongata from
the Dead Sea. This fact is the more interesting, because this species
is not found in the Mediterranean, but only in the Red Sea, which,
according to Valenciennes, has but few organisms in common with the
Mediterranean. As a sea-fish, a species of Pleuronectes, advances far
into the interior of France, and accustoms itself to gill-respiration
in fresh water, so also does a remarkable flexibility of organization
exist in the above-mentioned coral-animal (Porites elongata of
Lamarck), as the same species lives both in the Dead Sea, which is
supersaturated with salt, and in the open ocean near the Séchelles
Islands.[LK]

According to the most recent chemical analyses of the younger
Silliman, the genus Porites, like many other cellular coral-trunks
(Madrepores, Astræas, and Mæandrinas of Ceylon and the Bermudas),
contains besides from 92 to 95 per cent. of carbonate of lime and
magnesia, a portion of fluorine and phosphoric acid.[LL] The presence
of fluorine in the hard skeleton of the polyps reminds us of the
fluoride of calcium found in fish bones according to Morechini’s and
Gay-Lussac’s experiments at Rome. Silex is mixed only in very small
quantities, with the fluoride of calcium and phosphate of lime found
in the coral-trunks; but one coral animal allied to the Horn corals
(Gray’s _Hyalonema_, Glass thread) has an axis of fibres of pure
silex, resembling a hanging tuft of hair. Professor Forchhammer, who
has recently been engaged in a thorough analysis of sea-water in the
most opposite parts of the earth’s surface, finds the quantity of lime
in the Caribbean Sea remarkably small, it being only ²⁴⁷⁄₁₀₀₀₀, whilst
in the Cattegat it amounts to ³⁷¹⁄₁₀₀₀₀. He is disposed to ascribe
this difference to the numerous coral-banks near the West India
Islands, which appropriate the lime to themselves, and thus exhaust
the sea-water.[LM]

Charles Darwin has with great ingenuity developed the genetic
connection between shore-reefs, island-encircling reefs, and lagoon
islands, _i. e._, narrow, annular coral banks which surround inner
lagoons. According to his views, these three kinds of structure depend
upon the oscillating condition of the bottom of the sea, or on
periodical elevations and subsidences. The often-advanced hypothesis,
according to which the lagoon-islands, or atolls, mark by their
circularly enclosed coral-reefs, the outline of a submarine crater,
raised on a volcanic crater-margin, is opposed by the great extent of
their diameters, which are in some instances upwards of 30, 40, or
even 60 miles. Our fire-emitting mountains have no such craters, and
if we would compare the lagoon, with its submerged mural surface and
narrow encircling reef, with one of the annular lunar mountains, we
must not forget that these annular mountains are not volcanoes, but
tracts of land enclosed by walls. According to Darwin, the following
is the process of formation. An island mountain closely encircled by a
coral reef subsides, while the _fringing_ reef that had sunk with it,
is constantly recovering its level owing to the tendency of the coral
animals to regain the surface by renewed perpendicular structures;
these constitute first a reef encircling the island at a distance, and
subsequently, when the inclosed island has wholly subsided, an
_atoll_. According to this view, which regards islands as the most
prominent parts, or the culminating points of the submarine land, the
relative position of the coral islands would disclose to us what we
could scarcely hope to discover by the sounding line, viz., the former
configuration and articulation of the land. This attractive subject
(to the connection of which with the migrations of plants and the
distribution of the races of men we drew attention at the beginning of
this note), can only be fully elucidated when we shall succeed in
acquiring further knowledge of the depth and nature of the different
rocks which serve as a foundation for the lower strata of the dead
polyp-trunks.

Footnote 78:

p. 216—“_Of the Samothracian Traditions_.”

Diodorus has preserved to us these remarkable traditions, the
probability of which has invested them with almost historical
certainty in the eyes of geologists. The island of Samothrace, once
also named Ethiopea, Dardania, and Leucania or Leucosia in the
Scholiast of Apollonius Rhodius, the seat of the ancient mysteries of
the Cabiri, was inhabited by the remnant of an aboriginal people,
several words of whose vernacular language were preserved in later
times in sacrificial ceremonies. The position of Samothrace, opposite
to the Thracian Hebrus, and near the Dardanelles, explains why a more
circumstantial tradition of the great catastrophe of an outburst of
the waters of the Pontus (Euxine) should have been especially
preserved in this island. Sacred rites were here performed at altars
erected on the supposed limits of this inundation; and among the
Samothracians, as well as the Bœetians, a belief in the periodical
destruction of the human race (a belief which also prevailed among the
Mexicans in their myth of the four destructions of the world) was
associated with historical recollections of individual
inundations.[LN] According to Diodorus, the Samothracians related that
the Black Sea had been an inland lake, which, swelled by the influx of
rivers (long prior to the inundations which had occurred among other
nations) had burst, first through the straits of the Bosphorus, and
subsequently through those of the Hellespont.[LO] These ancient
revolutions of nature have been considered in a special treatise, by
Dureau de la Malle, and all the facts known regarding them collected
by Carl von Hoff, in an important work on the subject.[LP] The
Samothracian traditions seem reflected as it were in the Sluice-theory
of Strato of Lampsacus, according to which the swelling of the waters
in the Euxine first formed the passage of the Dardanelles, and next
the opening through the Pillars of Hercules. Strabo, in the first book
of his Geography, has preserved among the critical extracts from the
works of Eratosthenes, a remarkable fragment of the lost work of
Strato, which presents views that embrace almost the whole
circumference of the Mediterranean.

“Strato of Lampsacus,” says Strabo,[LQ] “enters more fully than the
Lydian Xanthus (who has described the impressions of shells far from
the sea) into a consideration of the causes of these phenomena. He
maintains, that the Euxine had formerly no outlet at Byzantium, but
that the pressure of the swollen mass of waters caused by the influx
of rivers had opened a passage, whereupon the water rushed into the
Propontis and the Hellespont. The same thing also happened to _our_
sea (the Mediterranean), for here too a passage was opened through the
isthmus at the Pillars of Hercules, in consequence of the filling of
the sea by currents, which in flowing off left the former swampy banks
uncovered and dry. In proof of this, Strato affirms, first, that the
outer and inner bottoms of the sea are different; then that there is
still a bank running under the sea from Europe to Lybia, which shows
that the inner and outer sea were formerly not united; next that the
Euxine is extremely shallow, while the Cretan, the Sicilian and the
Sardinian seas are, on the contrary, very deep; the cause of this
being that the former is filled with mud from the numerous large
rivers flowing into it from the north. Hence too the Euxine is the
freshest, and the streams flowing from it are directed towards the
parts where the bottom is deepest. It would also appear that if these
rivers continue to flow into the Euxine, it will some day be
completely choked with mud, for even now, its left side is becoming
marshy in the direction of Salmydessus (the Thracian Apollonia), at
the part called by mariners ‘The Breasts,’ before the mouth of the
Ister and the desert of Scythia. Perhaps, therefore, the Lybian Temple
of Ammon may also have once stood on the sea-shore, its present
position in the interior of the country being in consequence of such
off-flowings of rivers. Strato also conjectures that the fame and
celebrity of the Oracle (of Ammon) is more easily accounted for, on
the supposition that the temple was on the sea-shore, since its great
distance from the coast would otherwise make its present distinction
and fame inexplicable. Egypt also was in ancient times overflowed by
the sea as far as the marshes of Pelusium, Mount Casius, and Lake
Serbonis; for whenever in digging it happened that salt-water was met
with, the borings passed through strata of sea-sand and shells, as if
the country had been inundated, and the whole district around Mount
Casius and Gerrha had been a marshy sea, continuous with the Gulf of
the Red Sea. When the sea (the Mediterranean) retreated, the country
was uncovered, leaving, however, the present Lake Serbonis.
Subsequently the waters of this lake also flowed off, converting its
bed into a swamp. In like manner the banks of Lake Mœris resemble more
the shores of a sea than those of a river.” An erroneous reading
introduced as an emendation by Grosskurd, in consequence of a passage
in Strabo,[LR] gives in place of Mœris, “the Lake Halmyris,” but the
latter was situated near the southern mouth of the Danube.

The Sluice-theory of Strato led Eratosthenes of Cyrene (the most
celebrated in the series of the librarians of Alexandria) to
investigate the problem of the uniformity of level in all external
seas flowing round continents, although with less success than
Archimedes in his treatise on floating bodies.[LS] The articulation of
the northern coasts of the Mediterranean as well as the form of its
peninsulas and islands had given origin to the geognostic myth of the
ancient land of Lyctonia. The origin of the lesser Syrtis, of the
Triton Lake,[LT] and of the whole of Western Atlas,[LU] had been
embodied in an imaginary scheme of fire-eruptions and earthquakes.[LV]
I have recently entered more fully into this question,[LW] in a
passage with which I would be allowed to close this note:

“The northern shore of the Mediterranean possesses the advantage of
being more richly and variously articulated than the southern or
Lybian shore, and this was, according to Strabo, already noticed by
Eratosthenes. Here we find three peninsulas, the Iberian, the Italian,
and the Hellenic, which, owing to their various and deeply indented
contour, form, together with the neighbouring islands and the opposite
coasts, many straits and isthmuses. Such a configuration of continents
and of islands that have been partly severed and partly upheaved by
volcanic agency in rows, as if over far-extending fissures, early led
to geognostic views regarding eruptions, terrestrial revolutions, and
outpourings of the swollen higher seas into those below them. The
Euxine, the Dardanelles, the Straits of Gades, and the Mediterranean
with its numerous islands, were well fitted to originate such a system
of sluices. The Orphic Argonaut, who probably lived in the Christian
era, has interwoven old mythical narrations in his composition. He
sings of the division of the ancient Lyctonia into separate islands,
‘when the dark-haired Poseidon in anger with Father Kronion struck
Lyctonia with the golden trident.’ Similar fancies, which may often
certainly have sprung from an imperfect knowledge of geographical
relations, were frequently elaborated in the erudite Alexandrian
school, which was so devoted to everything connected with antiquity.
Whether the myth of the breaking up of Atlantis be a vague and western
reflection of that of Lyctonia, as I have elsewhere shown to be
probable, or whether, according to Otfried Müller, ‘the destruction of
Lyctonia (Leuconia) refers to the Samothracian tradition of a great
flood, which changed the form of that district,’ is a question which
it is here unnecessary to decide.”

Footnote 79:

p. 217—“_Precipitation from the clouds_.”

The vertical ascent of currents of air is one of the principal causes
of the most important meteorological phenomena. Where a desert or a
sandy surface devoid of vegetation is surrounded by a high
mountain-chain, the sea-wind may be observed driving a dense cloud
over the desert, without any precipitation of vapour taking place
before it reaches the crest of the mountains. This phenomenon was
formerly very unsatisfactorily referred to an _attraction_ supposed to
be exercised by the mountain-chain on the clouds. The true cause
appears to lie in the ascent from the sandy plain of a column of warm
air, which prevents the condensation of the vesicles of vapour. The
more barren the surface, and the greater the degree of heat acquired
by the sand, the higher will be the ascent of the clouds, and the less
readily will the vapour be precipitated. Over the declivities of
mountains these causes cease. The play of the vertical column of air
is there weaker; the clouds sink, and their disintegration is effected
by a cooler stratum of air. Thus _deficiency of rain_ and _absence of
vegetation in the desert_ stand in a reciprocal action to one another.
It does not rain because the barren and bare surface of sand becomes
more strongly heated and radiates more heat; and the desert is not
converted into a steppe or grassy plain because without water no
organic development is possible.

Footnote 80:

p. 218—“_The indurating and heat-emitting mass of the earth_.”

If according to the hypothesis of the Neptunists (now long since
obsolete), the so-called primitive rocks were also precipitated from a
fluid, the transition of the earth’s crust from a condition of
fluidity to one of solidity, must have been followed by the liberation
of an enormous quantity of caloric, which would have given rise to new
evaporation and new precipitations. The more recent these
precipitations, the more rapid, the more tumultuous, and the more
uncrystalline would they have been. Such a sudden liberation of
caloric from the indurating crust of the earth, independent of the
latitude, and the position of the earth’s axis, might indeed occasion
local elevations of temperature in the atmosphere, which would
influence the distribution of plants. The same cause might also
occasion a kind of porosity which seems to be indicated by many
enigmatical geological phenomena in floetz rocks. I have developed my
conjectures on this subject in detail in a small memoir on primitive
porosity.[LX] According to the views I have more recently adopted, it
appears to me that the variously shattered and fissured earth, with
its fused interior, may long have continued in the primeval period, to
impart to its oxidised surface a high degree of temperature,
independent of its position with respect to the sun and to latitude.
What an influence would not, for instance, be exercised for ages to
come on the climate of Germany by an open fissure a thousand fathoms
in depth, extending from the Adriatic Gulf to the northern coast?
Although in the present condition of the earth, long-continued
radiation has almost entirely restored the stable equilibrium of
temperature first calculated by Fourier in his _Théorie analytique de
la Chaleur_, and the outer atmosphere is now only brought into direct
communication with the molten interior of the earth, by means of the
insignificant openings of a few volcanoes; yet in the primitive
condition of our planet, this interior emitted hot streams of air into
the atmosphere through the various clefts and fissures formed by the
frequently recurring foldings (or corrugations) of the mountain
strata. This emission was wholly independent of latitude. Every newly
formed planet must thus in its earliest condition have regulated its
own temperature, which was, however, subsequently changed and
determined by its position in relation to the central body, the sun.
The moon’s surface also exhibits traces of this reaction of the
interior upon the crust.

Footnote 81:

p. 218—“_The mountain-declivities of the most southern parts of
Mexico_.”

The spherical greenstone in the mountain district of Guanaxuato is
perfectly similar to that of the Fichtelberg in Franconia. Both form
grotesque domes, which break through and are superimposed on
transition argillaceous schists. In the same manner pearl-stone,
porphyritic schist, trachyte, and pitch-stone porphyry present
analogous forms in the Mexican mountains, near Cinapecuaro and Moran,
in Hungary, Bohemia, and in Northern Asia.

Footnote 82:

p. 220—“_The Colossal Dragon-tree of Orotava_.”

This colossal dragon-tree (Dracæna draco) stands in the garden of M.
Franqui, in the little town of Orotava, called formerly Taoro, one of
the most charming spots in the world. In June, 1799, when we ascended
the Peak of Teneriffe, we found that this enormous tree measured 48
feet in circumference. Our measurement was made at several feet above
the root. Nearer to the ground Le Dru found it nearly 79 feet. Sir G.
Staunton asserts that at an elevation of ten feet from the ground, its
diameter is still 12 feet. The height of the tree is not much more
than 69 feet. According to tradition it would appear that this tree
was venerated by the Guanches (as was the ash-tree of Ephesus by the
Greeks, the Plantain of Lydia, which Xerxes decorated with ornaments,
also the sacred Banyan-tree of Ceylon), and that in the year 1402,
which was the period of Béthencourt’s first expedition, it was as
large and as hollow as in the present day. When it is remembered that
the dragon-tree is everywhere of very slow growth, we may conclude
that the one at Orotava is of extreme antiquity. Berthollet says, in
his description of Teneriffe, “On comparing the young dragon-trees
which grows near this colossal tree, the calculations we are led to
make on the age of the latter strike the mind with astonishment.”[LY]
The Dragon-tree has been cultivated from the most ancient times in the
Canary isles, in Madeira, and Porto Santo, and that accurate observer,
Leopold von Buch, found it growing wild near Iguesti in Teneriffe. Its
original habitat is not therefore the East Indies, as has long been
believed; and its appearance does not afford any refutation of the
opinion of those who regard the Guanches as a wholly isolated
primitive Atlantic race, having no intercourse with African or Asiatic
nations: The form of the _Dracænæ_ is repeated on the southern
extremity of Africa, in the Isle of Bourbon, in China, and in New
Zealand. In these remotely distant regions we recognise species of the
same genus, but none are to be found in the New Continent, where this
form is supplied by the Yucca. The _Dracæna borealis_ of Aiton is a
true _Convallaria_, the nature of both being perfectly identical.[LZ]

I have given a representation, in the last plate of the Picturesque
Atlas of my American journey,[MA] of the dragon-tree of Orotava, taken
from a drawing made in 1776 by F. d’Ozonne, and which I found among
the posthumous papers of the celebrated Borda, in the still unprinted
journal entrusted to me by the Dépôt de la Marine, and from which I
have borrowed important astronomically-determined geographical, data
besides many barometrical and trigonometrical notices.[MB] The
measurement of the dragon-tree in the Villa Franqui was made in
Borda’s first voyage with Pingré in 1771, and not in the second, made
1776 with Varela. It is asserted, that in the fifteenth century,
during the early periods of the Norman and Spanish conquests, mass was
performed at a small altar erected in the hollow trunk of this tree.
Unfortunately, the Dracæna of Orotava lost one side of its leafy top
in the storm of the 21st of July, 1819. There is a fine large English
copper-plate engraving, which gives an exceedingly true representation
of the present condition of the tree.

The monumental character of these colossal living forms, and the
impression of reverence which they have created among all nations,
have led, in modern times, to a more careful study of the numerical
determination of their age, and of the size of their trunks. The
results of such investigations induced the elder Decandolle, (the
author of the important treatise, entitled _De la Longévité des
Arbres_,) Endlicher, Unger, and other distinguished botanists to
conjecture, that the age of many existing vegetable forms may extend
to the earliest historical times, if not to the records of the Nile,
at least to those of Greece and Italy. In the _Bibliothèque
Universelle de Genève_ (t. xlvii. 1831, p. 50) we find the following
passage: “Numerous examples seem to confirm the idea, that there still
exist, on our planet, trees of a prodigious antiquity—the witnesses,
perhaps, of one or more of its latest physical revolutions. If we
consider a tree as the combination of as many individual forms as
there have been buds developed on its surface, one cannot be surprised
if the aggregate resulting from the continual addition of new buds to
the older ones, should not necessarily have any fixed termination to
its existence.” In the same manner, Agardh says: “If in each solar
year new parts be formed in the plant, and the older hardened ones be
replaced by new parts capable of conducting sap, we have a type of
growth limited by external causes alone.” He ascribes the short
duration of the life of herbaceous plants, “to the preponderance of
the production of blossoms and fruit over the formation of leaves.”
Unfruitfulness in a plant insures a prolongation of its life.
Endlicher adduces the instance of an individual plant of Medicago
sativa, var. β versicolor, which lived eighty years because it bore no
fruit.[MC]

To the dragon-trees, which, notwithstanding the gigantic development
of their closed vascular bundles, must be classed, in respect to their
floral parts, in the same natural family as Asparagus and the garden
onion, belongs the Adansonia, (the monkey bread-tree, _Baobab_),
undoubtedly among the largest and most ancient inhabitants of our
planet. In the earliest voyages of discovery made by Catalans and
Portuguese, the sailors were accustomed to carve their names on these
two species of trees; not always from a mere wish of perpetuating
their memory, but also as “marcos,” or signs of possession, and of the
rights which nations assume in virtue of first discovery. The
Portuguese mariners often selected for carving on the trees, as a
“marco,” or mark of possession, the elegant French motto _talent de
bien faire_, so frequently employed by the Infante Don Henrique, the
Discoverer. Thus Manuel de Faria y Sousa says expressly;[MD] “Era uso
de los primeros Navegantes de dexar inscrito el motto del Infante,
_talent de bien faire_, en la corteza de los arboles.”[ME] (It was the
custom of the early navigators to inscribe the motto of the Infante in
the bark of the trees.)

The above-named motto, cut on the bark of two trees by Portuguese
navigators in the year 1435, and therefore twenty-eight years before
the death of the Infante Don Henrique, Duke of Viseo, is singularly
connected, in the history of discoveries, with the discussions that
have arisen from a comparison of Vespucci’s fourth voyage with that of
Gonzalo Coelho (1503). Vespucci relates, that the Admiral’s ship of
Coelho’s squadron was wrecked on an island which was sometimes
supposed to be that of San Fernando Noronha; sometimes, Peñedo de San
Pedro; and sometimes, the problematical island of St. Matthew. The
last-named island was discovered on the 15th of October, 1525, by
Garcia Jofre de Loaysa in 2½ south lat., in the meridian of Cape
Palmas, and almost in the Gulf of Guinea. He remained there eighteen
days at anchor, and found crosses, orange-trees that had become wild,
and two trunks of trees having inscriptions that bore the date of
ninety years back.[MF] I have in another place,[MG] in an inquiry
regarding the trustworthiness of Amerigo Vespucci, more fully
considered this problem.

The oldest description of the Baobab (Adansonia digitata) is that of
the Venetian, Aloysius Cadamosto. (whose real name was Alvise da Ca da
Mosto) in 1454. He found at the mouth of the Senegal. (where he joined
Antoniotto Usodimare), trunks, whose circumference he estimated at 17
fathoms, or 112 feet.[MH] He might have compared them to dragon-trees,
which he had already seen. Perrottet says,[MI] that he had seen
monkey-bread fruit trees, which had a diameter of about thirty-two
feet, with a height of only from seventy to eighty-five feet. The same
dimensions had been given by Adanson in his voyage, 1748. The largest
trunks of the monkey bread-fruit trees, which he himself saw, in 1749,
some on one of the small Magdalena islands near Cape de Verd, and
others at the mouth of the Senegal, were from 26 to nearly 29 feet in
diameter, with a height of little more than 70 feet, and a top
measuring upwards of 180 feet across. Adanson, however, makes the
remark that other travellers had found trunks having a diameter of
about 32 feet.[MJ] French and Dutch sailors had carved their names on
the trunks in characters six inches in length. One of these
inscriptions was of the fifteenth century,[MK] while all the others
were of the sixteenth. From the depth of the cuts, which are covered
with new layers of wood,[ML] and from a comparison of the thickness of
trunks, whose various ages were known, Adanson computed the age of
trees having a diameter of 32 feet at 5150 years.[MM] He however
cautiously subjoins the following remarks, in a quaint mode of
spelling which I do not alter: “le calcul de l’aje de chake couche n’a
pas d’exactitude géometrike.” In the village of Grand Galarques, also
in Senegambia, the negroes have adorned the entrance of a hollow
Baobab with carvings cut out of wood still green. The inner cavity
serves as a place of general meeting in which the community debate on
their interests. This hall reminds us of the hollow (specus) in the
interior of a plantain in Lycia, in which the Roman ex-consul,
Lucinius Mutianus, entertained twenty-one guests. Pliny (xii. 3) gives
to a cavity of this kind the somewhat ample breadth of eighty Roman
feet. The Baobab was seen by René Caillié in the valley of the Niger
near Jenne, by Cailliaud in Nubia, and by Wilhelm Peters along the
whole eastern coast of Africa, where this tree, which is called
_Mulapa_, _i.e._ _Nlapa-tree_, or more correctly _muti-nlapa_,
advances as far as Lourenzo Marques, almost to 26° south lat. The
oldest and thickest trunks seen by Peters “measured from 60 to 75 feet
in circumference.” Although Cadamosto observed, in the fifteenth
century, _eminentia non quadrat magnitudini_; and although
Golberry[MN] found, in the “Vallée des deux Gagnacks,” trunks only 64
feet in height whose diameter was 36 feet, this disproportion between
thickness and height must not be assumed to be general. “Very old
trees,” says the learned traveller, Peters, “lose their crowns by
gradual decay, while they continue to increase in circumference. On
the eastern coast of Africa one not unfrequently meets with trees
having a diameter of more than 10 feet which reach the height of
nearly 70 feet.”

While therefore the bold calculations of Adanson and Perrottet assign
to the Adansonias measured by them, an age of 5150 or even 6000 years,
which would make them coeval with the builders of the Pyramids, or
even with Menes, and would place them in an epoch when the Southern
Cross was still visible in Northern Germany;[MO] the more certain
estimations yielded by annular rings, and by the relation found to
exist between the thickness of the layer of wood and the duration of
growth, give us, on the other hand, shorter periods for our temperate
northern zone. Decandolle finds that of all European species of trees,
the yew attains the greatest age; and according to his calculations,
30 centuries must be assigned as the age of the _Taxus baccata_ of
Braburn in Kent, from 25 to 26 to the Scotch yew of Fortingal, and 14½
and 12 respectively to those of Crowhurst in Surrey and Ripon
(Fountains Abbey) in Yorkshire.[MP] Endlicher remarks that “another
yew-tree in the churchyard of Grasford, North Wales, which measures
more than 50 feet in girth below the branches, is more than 1400 years
old, whilst one in Derbyshire is estimated at 2096 years. In Lithuania
linden trees have been felled which measured 87 feet round, and in
which 815 annular rings have been counted.”[MQ] In the temperate zone
of the southern hemisphere some species of the Eucalyptus attain an
enormous girth, and as they at the same time attain a height of nearly
250 feet, they afford a singular contrast to our yew trees, which are
colossal only in thickness. Mr. Backhouse found in Emu Bay, on the
shore of Van Diemen’s Land, Eucalyptus trunks which, with a
circumference of 70 feet at the base, measured as much as 50 feet at a
little more than 5 feet from the ground.[MR]

It was not Malpighi, as has been generally asserted, but the
intellectual Michel Montaigne, who had the merit of first showing, in
1581, in his _Voyage en Italie_, the relation that exists between the
annual rings and the age of the tree.[MS] An intelligent artisan,
engaged in the preparation of astronomical instruments, first drew
Montaigne’s attention to the significance of the annual rings,
asserting that the part of the trunk directed towards the north had
narrower rings. Jean Jacques Rousseau entertained the same opinion;
and his Emile, when he loses himself in the forest, is made to direct
his course in accordance with the deposition of the layers of wood.
Recent phyto-anatomical observations[MT] teach us, however, that the
acceleration of vegetation as well as the remission of growth, and the
varying production of the circles of the ligneous bundles (annual
deposits) from the cambium cells, depend on other influences than
position with respect to the quarter of the heavens.

Trees which in the case of some examples attain a diameter of more
than 20 feet, and an age of many centuries, belong to very different
natural families. We may here instance Baobabs, Dragon trees, various
species of Eucalyptus, Taxodium distichum. (Rich.,) Pinus Lambertiana.
(Douglasii,) Hymenæa Courbaril, Cæsalpinieæ, Bombax, Swietenia
Mahagoni, the Banyan tree (_Ficus religiosa_), Liriodendron
tulipifera(?), Platanus orientalis, and our Lindens, Oaks, and Yews.
The celebrated Taxodium distichon, the Ahuahuete of the Mexicans
(_Cupressus disticha_, Linn., _Schubertia disticha_, Mirbel), of Santa
Maria del Tule, in the State of Oaxaca, has not a diameter of 60 feet,
as stated by Decandolle, but exactly 40½ feet.[MU] The two beautiful
Ahuahuetes which I have frequently seen at Chapoltepec (growing in
what was probably once a garden or pleasure ground of Montezuma)
measure, according to the instructive account in Burkardt’s travels
(bd. i. s. 268) only 36 and 38 feet in circumference, and not in
diameter, as has often been erroneously maintained. The Buddhists of
Ceylon venerate the colossal trunk of the sacred fig-tree of
Anurahdepura. The Banyan, which takes root by its branches, often
attains a thickness of 30 feet, and forms, as Onesicritus truly
expresses himself, a leafy roof resembling a many-pillared tent.[MV]
On the Bombax Ceiba see early notices from the time of Columbus in
Bembo.[MW]

Among those oak trees which have been very accurately measured, the
largest in Europe is undoubtedly the one near Saintes on the road to
Cozes, in the Department de la Charente inférieure. This tree, which
has an elevation of 64 feet, measures very nearly 30 feet in diameter
near the ground, while 5 feet higher up it is nearly 23 feet, and
where the main branches begin more than 6 feet. A little room, from 10
feet 8 inches to 12 feet 9 inches in width and 9 feet 7 inches in
height, has been cleared in the dead part of the trunk, and a
semi-circular bench cut within it from the green wood. A window gives
light to the interior, and hence the walls of this little room, which
is closed by a door, are gracefully clothed with ferns and lichens.
From the size of a small piece of wood that had been cut out over the
door, and in which two hundred ligneous rings were counted, the age of
the oak of Saintes must be estimated at 1800 or 2000 years.[MX]

With respect to the rose-tree (_Rosa canina_) reputed to be a thousand
years old, which grows in the crypt of the Cathedral of Hildesheim, I
learn from accurate information, based on authentic records, for which
I am indebted to the kindness of the Stadtgerichts-Assessor Römer,
that the main stem only has an age of eight hundred years. A legend
connects this rose-tree with a vow of the first founder of the
cathedral, Louis the Pious; and a document of the eleventh century
says, “that when Bishop Hezilo rebuilt the cathedral, which had been
burnt down, he enclosed the roots of the rose-tree within a vault
still remaining, raised on the latter the walls of the crypt, which
was re-consecrated in 1061, and spread the branches of the rose-tree
over its sides.” The stem, still living, is nearly 27 feet in height,
and only 2 inches thick, and spreads across a width of 82 feet over
the outer wall of the eastern crypt. It is undoubtedly of very
considerable antiquity, and well worthy of the renown it has so long
enjoyed throughout Germany.

If excessive size, in point of organic development, may in general be
regarded as a proof of a long protraction of life, special attention
is due, among the thalassophytes of the submarine vegetable world, to
a species of fucus, _Macrocystis pyrifera_, Agardh (_Fucus
giganteus_). This marine plant attains, according to Captain Cook and
George Forster, a length of 360 feet, and exceeds therefore the height
of the loftiest Coniferous trees, not excepting _Sequoia gigantea_,
Endl. (_Taxodium sempervirens_, Hook, and Arnott) of California.[MY]
Captain Fitz-Roy has confirmed this statement.[MZ] Macrocystis
pyrifera grows from 64° south lat. to 45° north lat., as far as the
Bay of San Francisco on the north-west coast of the New Continent;
indeed Joseph Hooker believes that this species of Fucus advances as
far as Kamtschatka. In the waters of the Antarctic seas it is even
seen floating between the pack-ice.[NA] The cellular band and
thread-like structures of the Macrocystis (which are attached to the
bottom of the sea by an adhesive organ resembling a claw) seem to be
limited in their length by accidental disturbing causes alone.

Footnote 83:

p. 220—“_Phanerogamic plants already recorded in herbariums_.”

Three questions must be carefully distinguished from one another: 1.
How many species of plants have been described in printed works? 2.
How many of those discovered—that is to say included in
herbariums—still remain undescribed? 3. How many species probably
exist on the surface of the earth? Murray’s edition of the Linnæan
system contains, including cryptogamic plants, only 10,042 species.
Willdenow, in his edition of the _Species Plantarum_ from 1797 to
1807, has described as many as 17,457 species of phanerogamia,
reckoning from Monandria to Polygamia diœcia. If to these we add 3000
species of cryptogamic plants, we shall bring the number as given by
Willdenow to 20,000. More recent investigations have shown how far
this estimate of the species described, and of those preserved in
herbariums, falls short of the truth. Robert Brown[NB] first
enumerated above 37,000 phanerogamia, and I at that time attempted to
describe the distribution of 44,000 species of phanerogamic and
cryptogamic plants, over the different portions of the world already
explored.[NC] Decandolle finds, on comparing Persoon’s _Enchiridium_
with his _Universal System divided into twelve families_, that more
than 56,000 species of plants may be enumerated from the writings of
botanists and European herbariums.[ND] If we consider how many new
species have been described by travellers since that time, (my
expedition alone afforded 3600 of the 5800 collected species of
equinoctial plants), and if we bear in mind that there are assuredly
upwards of 25,000 phanerogamic plants, cultivated in all the different
botanical gardens, we shall soon see how much Decandolle’s estimate is
below the truth. From our complete ignorance of the interior of South
America (Mato-Grosso, Paraguay, the eastern declivity of the Andes,
Santa-Cruz de la Sierra, and all the countries lying between the
Orinoco, the Rio Negro, the Amazon, and Puruz), of Africa, of
Madagascar, and Borneo, and of Central and Eastern Asia, the idea
involuntarily presents itself to the mind that we are not yet
acquainted with one third, or probably even with one fifth part of the
plants existing on the earth. Drège has collected 7092 phanerogamic
species in Southern Africa alone; and he believes that the flora of
that region consists of more than 11,000 phanerogamic species, seeing
that in Germany and Switzerland, on an equal area (192,000 square
miles,) Koch has described only 3300, and Decandolle only 3645
phanerogamia in France. I would here also instance the new genera,
consisting partly of high forest trees, which are still being
discovered in the neighbourhood of large commercial towns in the
lesser Antilles, although they have been visited by Europeans for the
last three hundred years. Such considerations, which I purpose
developing more fully at the close of this illustration, seem to
verify the ancient myth of the Zend-Avesta, that “the creating
primeval force called forth 120,000 vegetable forms from the sacred
blood of the bull.”

If therefore no direct scientific solution can be afforded to the
question, how many vegetable forms—leafless cryptogamia (water algæ,
fungi, and lichens), characeæ, liverworts, foliaceous mosses,
marsilaceæ, lycopodiaceæ, and ferns—exist on the dry land, and in the
wide basin of the sea, in the present condition of the organic
terrestrial life of our planet, it only remains for us to employ an
approximative method for ascertaining with some degree of probability
certain “extreme limits” (numerical data of minima). Since the year
1815, I have, in my arithmetical considerations on the geography of
plants, calculated the numbers expressing the ratio which the
aggregate of species of different natural families bears to the whole
mass of the phanerogamia in those countries where the latter is
sufficiently determined. Robert Brown,[NE] the greatest botanist of
our age, had, prior to my researches, already determined the numerical
proportion of the principal divisions of vegetable forms, as for
instance of acotyledons (_Agamæ_, cryptogamic or cellular plants) to
cotyledons (_Phanerogamia_, or vascular plants), and of monocotyledons
(_Endogenæ_) to dicotyledons (_Exogenæ_). He finds the ratio of
monocotyledons to dicotyledons in the tropical zone as in the
proportion of 1 to 5, and in the frigid zone, in the parallels of 60°
north, and 55° south lat. as 1 to 2½.[NF] The absolute numbers of the
species are compared together in the three great divisions of the
vegetable kingdom, according to the method developed in Brown’s work.
I was the first who passed from these principal divisions to the
individual families, and considered the number of the species
contained in each, in their ratio to the whole mass of phanerogamia
belonging to one zone.[NG]

The numerical relations of the forms of plants, and the laws observed
in their geographical distribution, admit of being considered from two
very different points of view. When we study plants in their
arrangement according to natural families, without regard to their
geographical distribution, the question arises: What are the
fundamental forms or types of organization, in accordance with which
the greater number of their species are formed? Are there more
Glumaceæ than Compositæ on the earth’s surface? Do these two orders of
plants combined, constitute one-fourth of the phanerogamia? What
numerical relation do monocotyledons bear to dicotyledons? These are
questions of general phytology, a science that investigates the
organization of plants and their mutual connection, and therefore has
reference to the now existing state of vegetation.

If, on the other hand, the species of plants that have been connected
together according to their structural analogy, are considered not
abstractedly, but in accordance with their climatic relations, and
their distribution over the earth’s surface, these questions acquire a
totally different interest. We then examine what families of plants
predominate in the torrid zone more than towards the polar circle over
other phanerogamia? We inquire, whether the Compositæ are more
numerous in the new than in the old world, under equal geographical
latitudes or between equal isothermal lines? Whether the forms which
gradually lose their predominance in advancing from the equator to the
poles, follow a similar law of decrease in ascending mountains
situated in the equatorial region? Whether the relations of the
different families to the whole mass of the phanerogamia differ under
equal isothermal lines in the temperate zones on either side of the
equator? These questions belong to the geography of plants properly so
called, and are connected with the most important problems that can be
presented by meteorology and terrestrial physics. Thus the
predominance of certain families of plants determines the character of
a landscape, and whether the aspect of the country is desolate or
luxuriant, or smiling and majestic. Grasses, forming extended
Savannahs, or the abundance of fruit-yielding palms, or social
coniferous trees, have respectively exerted a powerful influence on
the material condition, manners, and character of nations, and on the
more or less rapid development of their prosperity.

In studying the geographical distribution of forms, we may consider
the species, genera, and natural families of plants separately. A
single species, especially among social plants, frequently covers an
extensive tract of land. Thus we have in the north, Pine or Fir
forests, and Heaths (_ericeta_); in Spain, Cistus groves; and in
tropical America, collections of one and the same species of Cactus,
Croton, Brathys, or Bambusa Guadua. It is interesting to study more
closely these relations of individual increase, and of organic
development; and here we may inquire, what species produces the
greatest number of individuals in one certain zone; or, merely what
are the families to which the predominating species belong in
different climates. In a very high northern latitude, where the
Compositæ and the Ferns stand in the ratios of 1 : 13 and 1 : 25 to
the sum of all the phanerogamia (_i. e._, where these ratios are found
by dividing the sum total of all phanerogamia by the number of species
included in the family of the Compositæ, or in that of the Ferns); one
single species of Fern may, however, cover ten times more space than
all the species of the Compositæ taken together. In this case the
Ferns predominate over the Compositæ by their mass, and by the number
of the individuals belonging to the same species of Pteris, or
Polypodium; but they will not be found to predominate, if we only
compare the number of the different specific forms of the Filices, and
of the Compositæ, with the sum total of all Phanerogamia. As,
therefore, multiplication of plants does not follow the same laws in
all species, and as all do not produce an equal number of individuals,
the quotients obtained by dividing the sum of all phanerogamic plants
by the species of one family, do not _alone_ determine the leading
features impressed on the landscape, or the physiognomy of nature
peculiar to different regions of the earth. If the attention of the
travelling botanist be arrested by the frequent repetition of the same
species, by its mass, and the uniformity of vegetation thus produced,
it will be still more forcibly arrested by the infrequency of many
other species useful to man. In tropical regions, where the Rubiaceæ,
Myrtles, Leguminosæ, or Terebinthaceæ, compose the forests, one is
astonished to meet with so few trees of Cinchona, or of certain
species of mahogany (_Swietenia_), of Hæmatoxylon, Styrax, or balsamic
Myroxylon. I would also here refer to the scanty and detached
occurrence of the precious febrifuge-bark trees (species of Cinchona)
which I had an opportunity of observing on the declivity of the
elevated plains of Bogota and Popayan, and in the neighbourhood of
Loxa, in descending towards the unhealthy valley of the Catamayo, and
to the river Amazon. The _febrifuge-bark hunters_ (Cazadores de
Cascarilla), as those Indians and Mestizoes are called at Loxa, who
each year collect the most efficacious of all the medicinal barks, the
_Cinchona Condaminea_, among the lonely mountains of Caxanuma,
Uritusinga, and Rumisitana, undergo considerable danger in climbing to
the summits of the highest forest-trees, in order to obtain an
extended view, from which they may distinguish the scattered, slender,
and aspiring trunks of the Cinchona, by the reddish tint of their
large leaves. The mean temperature of this important forest region
(between 4° and 4½° south lat.) varies from 60° to 68° Fahr., at an
absolute height of from 6400 to 8000 feet above the level of the
sea.[NH]

In considering the distribution of species, we may also, independently
of individual multiplication and mass, compare together the absolute
number which belong to each family. Such a mode of comparison, which
was employed by Decandolle,[NI] has been extended by Kunth to more
than 3300 of the species of Compositæ with which we are at present
acquainted. It does not show what family preponderates by individual
mass, or by the number of its species, over other phanerogamic forms,
but it simply indicates how many of the species of one and the same
family are indigenous in any one country or portion of the earth. The
results of this method are, on the whole, more exact, because they are
obtained by a careful study of the separate families, without
requiring that the whole number of the phanerogamia of every country
should be known. Thus, for instance, the most varied forms of Ferns
are found in the tropical zone, each genus presenting the greatest
number of species in the temperate, humid, and shaded mountainous
parts of islands. While these species are less numerous in passing
from tropical regions to the temperate zone, their _absolute number_
diminishes still more in approaching nearer to the poles. Although the
frigid zone, as, for instance, Lapland, supports species of the
families which are best able to resist the cold, Ferns predominate
more over other phanerogamia in Lapland than either in France or
Germany, notwithstanding the absolute inferiority of the gross number
of ferns indigenous to the northern zone, when compared with other
countries. These relations are, in France and Germany, as ¹⁄₇₃ and
¹⁄₇₁, while in Lapland they are as ¹⁄₂₅. These numerical relations
(obtained by dividing the sum total of all the phanerogamia of the
different floras by the species of each family) were published by me
in 1817, in my _Prolegomena de distributione geographica Plantarum_,
and corrected in accordance with the great works of Robert Brown, in
my Essay on the Distribution of Plants over the earth’s surface, which
I subsequently wrote in French. These relations, as we advance from
the equator towards the poles, necessarily vary from the ratios
obtained by a comparison of the absolute number of the different
species belonging to each family. We often see the value of the
fractions increase by the decrease of the denominator, whilst the
absolute number of the species is reduced. In the fractional method
which I have followed as the most applicable to questions relating to
the geography of plants, there are two variable quantities; for in
passing from one isothermal line to another, we do not find the sum
total of the phanerogamia change in the same proportion as the number
of the species of one particular family.