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call them, localized species, which are scattered more or
less widely among the more ordinary forms. And again,
a very few other parts are still more distinctly marked,
are made very distinCt areas, by the more or less corn-



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Notes on Plants at Roraima. 153

plete absence of the more ordinary forms and the sub-
stitution within their limits of an entirely new and
generally very distinft set of species. These areas with
a few localized species, of which several were passed by
us on our way to Roraima, and still more these areas of
quite distinft vegetation, of which the Kaieteur savan-
nah, across which we passed, and still more Roraima
itself, are remarkably fine examples, seem of the utmost
botanical interest.

A few notes must first be given of the species here
described as localized. It must be remembered that
these notes were made during a single walk, long as it
was, through a country otherwise almost absolutely un*
known ; so that though these species were noticed by
me because I saw them either only in one spot or at
least in very few spots — i.e. I passed through either only
one distinct group or through very few such groups of
them — yet it is of course impossible to assert that many
other such distinft groups do not occur wherever the
requisite soil and other circumstances permit.

A considerable number of such localized species occur
on tra&s where the soil is of so peculiar a nature as to
have earned a special name for such places from the
Indians, who call them Eppellings. This name is applied
by the Arekoonas to certain trafts in which the underly-
ing substance of very soft sandstone is overlaid by a
coating of hard dense and dry mud or, in some other
cases, of hard conglomerate. Wherever, as is often the
case, this hard mud surface is unbroken it resembles an
asphalt pavement, or perhaps rather a floor made of
hard-beaten earth. But this curious earth-surface over-
lies hill and dale alike, and is therefore not often level.

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154 TlMEHRI.



Wherever, then, there has been the slightest crack in
its surface, rain water gathers, and having once obtained
a lodgment it eats away and enlarges the crack. The
result is an eppelling surface which, instead of being like
an asphalt pavement, is like a pavement formed of irreg-
ularly-shaped and scattered flag-stones. But again, the
mud-layer which overlies the eppelling being by no
means thick, whenever this has once been indented, as
just described, by many cracks enlarged by water, these
cracks are soon engraved through the mud-layer down to
the soft sandstone below ; and, when this has once
occurred, the sandstone thus exposed, which yields to
the aflion of the water even more readily than does the
hard mud, is rapidly worked out. In this way the eppel-
ling is made to assume the form of a number of blocks,
often pillar-like, of sandstone, each of these blocks being
capped and prote6led by a patch of the original hard
earth, or, in other cases, of the original conglomerate.

Now, where the original eppelling surface is unbroken,
in which state we have compared it to an asphalt pave-
ment, it is as entirely devoid of vegetation as such an
artificial pavement would be. But where the surface of
the eppelling has reached its furrowed stage, a few plants
find lodgment, chiefly certain orchids and other such
plants, of which the roots are of such a nature that, in
the dry season, when the furrows are water-less, the
whole plant shrinks into complete rest, and even in some
cases loses its root-hold and is blown about on the
surface of the eppelling until, when the next rains
come, it again throws out anchor-like roots into some
new furrow. One orchid of this wandering tendency
is a Gatasetum (C. cristatum?) [No. 148] ; another is



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Notes on Plants at Roraima. 155

the new, and very beautiful Oncidium named and
described by Mr. Ridley in the appended list as
O. orthostates [No. 12]. Sometimes, too, in this same
state of the eppelling, especially where such ground
occurs on the brows of exposed hills, shrubs of consider-
able size find anchorage in the furrows and flourish. One
such hill-top which we passed was made very beautiful
in this way by a large and isolated patch of the large
rosy flowered Bonnetia sessilis, Benth, [No. ii]. In
another similar place we passed through a distin6lly
marked patch of the compaft Stiff tia condensate*. Baker*
[No. 10]. And more than one such place was distin-
guished by thickets of Gomphia guianensis [No. 15 J.

Lastly, as regards the eppellings, where the furrows of
these places have been worked down into the sandstone,
and have been much enlarged, the deep ravines and pits
of all sizes thus formed, though bare of vegetation
wherever the process of water- washing still continues in
violent a6lion, are where this aftion has ceased, owing to
the stoppage of the outlet, or has become much modera-
ted, compatively thickly clothed with vegetation.

Another remarkable localized plant, though not occur-
ring on an eppelling, was the beautiful Aphelandra
pulcherrima [No 14], It has already been said that
even on the otherwise open savannah, more or less
extensive belts of forests often clothe the sides of the
narrower parts of the valley through which the rivers
run'. One such place we came to, where, after crossing
the Ireng river and the low watershed which there
separates that river from its tributary the Karakanang,
we were descending toward the levej of the last-named
river. It was here that, in a somewhat extensive wood

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156 TlMEHRI.



of which most of the trees were common species of
Cassia, we found the dense, shrubby underwood to
consist almost entirely of this beautiful, scarlet flowered
Aphelandra.

Throughout a small traft on either side of the Ireng
river, where the ground was almost entirely covered by
a gravelly layer of shattered conglomerate, a very beau-
tiful herb, with flowers of an intense violet blue — a very
rare colour in Guiana, — was common and pleasantly
reminded me of our English 'vipers bugloss.' It was
Stachytarpheta mutabilis. v. [No. 1], which seems to me
to correspond to my description of a localized species.

Again, between the Ireng and the Cotinga rivers grew
in abundance, and evidently as a native, a plant [Four-
croya gigantea\ which, common enough near the coast
of Guiana in cultivation, is nowhere else, as far as I have
seen in many wanderings, wild in that colony.

Lastly, as regards localized species, I would mention
several dwarf bamboos, none of which unfortunately did
I succeed in finding in flower. One of these, a wonder-
fully graceful species, appears to me peculiar in Guiana,
in that it grows in dense thickets, on the open savannah.
This was on the Ireng river, and more sparingly onward
from there toward the Cotinga. Another of these bam-
boos (Chusquea [sp. ?] No. 18), I think the most graceful
plant I ever saw occurred sparingly, and only in one
spot, on the Arapoo river close to the village of Tooroi-
king. A third bamboo, a climbing form [No. 359], occurred
to me first on the same river, but is much more common
on Roraima itself, and should perhaps be spoken of in
connexion with the vegetation of that mountain.

Turning next to the areas of distinfl vegetation, the



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Notes on Plants at Roraima. 157

first to be mentioned is that of the Kaieteur savannah.*
This is certainly a very remarkable place with a
very remarkable vegetation. It is an open space,
some two miles long by one across, in the heart of
the ordinary dense forest, and some four days' journey
on foot from the nearest open country. It has been
said that the descent from the table-land of the inte-
rior toward the sea is not a gradual slope but occurs chiefly
in a series of steplike descents which are generally of
no great individual height. But the descent at the
Kaieteur takes the form of an almost abrupt cliff — at the
Kaieteur fall itself it is an aftual cliff — of between seven
and eight hundred feet in height The Potaro river, rising
apparently from the neighbourhood of, but not aftually
on, Roraima, after an unknown upper course of con-
siderable length, here runs along one side of the almost
perfectly level Kaieteur savannah and precipitates
itself, at the east end of that savannah, down the abrupt
descent of 800 feet. The savannah itself is virtually a
flat exposed rock, many parts of which are as absolutely
bare as a London pavement. This rock is sandstone,
which, as in the eppelling — indeed it probably is an
eppelling, but of unusually unbroken surface — is capped
by a harder material, by a layer of conglomerate. Just
as the hard surface of the eppel lings cracks and
eventually affords roothold in the fissures thus made for
plants, so the hard conglomerate covering of the
Kaieteur savannah has cracked, and in many of the
fissures thus produced has given root-hold to plants.

* A very instructive paper on * The aspect and flora of the Kaieteur
Savannah' by Mr. G. S. Jenman, F.L.S., is to be found in the firsr
volume of Timehri, p. 229.



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158 TlMEHRl.

Some of these latter fissures have gradually been filled
up by the accumulation of vegetable matter ; others
remain still open. On this savannah, however, the
fissures are larger than is commonly the case in
eppellings, are in fact often very long, though generally
narrow. Many of these are now entirely occupied
by shrubs and dwarf trees. The lines of these masses
of vegetation, necessarily following the lines of the
fissures, present, in most remarkable degree, the
appearance of the well marked Enes designed by a
landscape gardener ; and the whole effect is as of an arti-
ficial garden, with regular groups of shrubs separated by
wide paths and roads of clean bare rock. Moreover it is
not only in the fissures that plants grow on this savannah.
As on the eppellings so here to, a certain number of
plants find sufficient roothold in the vegetable accumula-
tions in the slight depressions in the conglomerate sheet
before these have been engraved deeply enough to leave
the sandstone exposed and to make regular fissures.

But not only is the arrangement of the vegetation of
the savannah thus very remarkable. The plants compos-
ing this vegetation are also individually of great interest.
As. might be expected, very few of them occur in the
forest which everywhere, and for a great distance,
surrounds this strange open space. Much more remark-
able is it that very few of these plants occur on the
nearest savannah, nor indeed, on the general savannah
land of the interior. And most noteworthy of all isit that a
very large number of these peculiar plants of this isolated
savannah occur, often with slight but interesting differ-
ences, on Roraima.

By far the most striking, as it is* also the most abun-



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Notes on Plants at Roraima. 159

datrt, plant on the Kaieteur savannah is a huge aloe-like
Brocchinia (B. cordylinoides, Baker) which was gathered
there by Mr. JENMAN and myself some years ago but
which was, until the Roraima expedition, unknown from
elsewhere. This gigantic plant, of such striking aspeft as
to compel notice even from the most unobservant travel-
ler, is ranged in enormous numbers over the Kaieteur sa-
vannah, and indeed makes, to a large extent, the strange-
ness of that strange scene. There the height of a full
grown specimen is, under the most favourable circumstan-
ces, about 15 feet ; and, in the older specimens at
least, the crown of leaves is supported on a tall bare
stem. It seems also there to flower abundantly. We
shall see that the plant occurs, but with slightly different
charafters, on Roraima. Moreover, at the Kaieteur, in
the axils of the leaves of this Brocchinia, end only in
that position, grows a very remarkable and beautiful
Utricularia (U. Humboldtii. Schk.), with flower stems
3 or 4 feet long, supporting many splendidly large violet
flowers. This plant too we shall find on Roraima, but
also with slightly different characters from those which
it exhibits at the Kaieteur. Another remarkable and
distinft plant on the Kaieteur savannah is a low-growing
Brocchinia (B. redufto, Baker,/, also previously known
only from there, which may be roughly described as
resembling three or four sheets of yellowish grey fools-
cap paper, rolled loosely one round the other, the whole
standing on one end of the roll. This plant I did not
observe on Roraima, though I feel convinced that it will
one day be found there ; but I did see it, in very consi-
derable quantity, in one small distriS about half way
between the Kaieteur and Roraima. Only one other



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I§0 TlMEHRI.



plant common, hut with a difference of form, to the two
distri&s can be mentioned here. Mr. Jenman found at
the Kaieteur a very striking new Moronobea (M. Jen-
manni) ; and I found on Roraima another very striking
new Moronobea (M. intermedia, N. sp., Engler No. 337)
of which its describer, says that its intermediate between
M. riparia and M. Jenmanni.

In short, the Kaieteur savannah and Roraima may be
regarded as two isolated areas marked by the very pecu-
liar vegetation, which vegetation is, however, to a note-
worthy extent, common to the two.

Before passing on to the distrift of Roraima, I may
mention that if I may judge from the reports of the
Indians, and of the one or two white men who have
been there, savannahs curiously like this very remark-
able example at the Kaieteur occur (1) above Amailah
fall on the Curiebrong river, a tributary of the Po-
taro, (2) above Orinidouie fall on the Ireng river,
and (3) above a certain very large fall which is re-
ported to exist — indeed I have myself heard the roar
of its waters — on the Potaro, about two days boat
journey above the Kaieteur, In each of these places
the large and not easily mistakable Brocchinia cordyli-
noides is credibly said to occur ; and it seems highly
probable that, with this, some of the other, but less
conspicuous, plants of the Kaieteur occur also on these
other savannahs. In short, it may very probably be
that each of these reported fall-savannahs is a distinft
area, parallel, and similar in vegetation to the Kaieteur
savannah and to Roraima. In passing it may also here
be noted that apparently a Brocchinia, similar to B.
cordylinoides occurs on the Organ Mountains near Rio



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Notes on Plants at Roraima. 16*

in Brazil, reached by GARDNER in 1837, and that in the
axils of its leaves occurs an Utricularia (U. nelumbifolia^
which, to judge from GARDNER'S passing descriptions,
must be strikingly similar to U. Humboldtii as it occurs
on the Kaieteur savannah.* Possibly, nay probably, the
Organ Mountains, too, resemble in some other of their
vegetable features the Kaieteur savannah and Roraima.

Let us now pass to the consideration of Roraima itsett
as an area of distinft vegetation. And in so doing a few
words must just be said to recall the physical features of
the mountain.

Roraima is one, certainly the best known, perhaps the
most remarkable, of a group of pillar-like sandstone
mountains capped with hard conglomerate, which group
is, it seems to me, identical in nature and origin with the
groups of sandstone pillars, capped with conglomerate or
hardened mud, of the eppellings already described. In
short, Roraima and its fellow mountains seem to be an
eppelling on a gigantic scale. Some notion of how large
the scale is may be gathered from the fa6ts that Roraima
itself, one pillar of the group, is almost exaftly four
miles wide along its south-eastern face, and is apparently
seven or eight miles long from south to north, and that
its height is some 5,000 feet above the general level of
the plain from which it rises.f

* Gardner's description of the vegetation of the Organ mountains
(see his " Travels in Brazil." London, 1849. Especially pp. 50-52 and
402-403) reads extraordinarily like an account of the vegetation of
Roraima. The height of the two elevations is about the same, but the
Organ range consists almost exclusively of granite, not, as does
Roraima, of sandstone.

t In a recent number of the Proceedings of the Royal Geographical
Society (June 1886) is a paper by Mr. James W. Wells, C.E., on a

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162 TlMEHRI.

This 5,000 feet of height, it must be explained, is
made up of a sloping base, the pediment of the pillar,
of about 3,000 feet, which is surmounted by the more
9triftly pillar-like portion, 2,000 feet in height. The
plateau on top of the pillar is a very slightly, indeed
almost imperceptibly, hollowed basin — four miles wide
by some seven or eight miles long, it must be remem-
bered — over which are scattered innumerable single
rocks and piles of rocks, the largest of which are appar-
ently some eighty or ninety feet in height. The sloping
basal part of the mountain is, everywhere but toward
the south-east covered by dense, but not lofty, forest ;
while on the south-east a considerable portion of it,
which portion does not however extend up to the foot of
the aftual cliff, is treeless and grass-covered. The cliff
itself is bare, but for a comparatively few mosses, ferns,
grasses and trailing plants clinging closely to the rougher
parts of its surface, especially where the many water-falls
trickle down the rock-face, and for the dwarf shrubs,
ever dwarfer and more alpine in charafter toward the
top, which have found a lodgement on the few trans-
verse ledges which break the evenness of the surface.
The hollow basin at the top of the pillar is, wherever a
little soil has accumulated in the depressions of the bare

group of mountains apparently very similar in physical feature to Ro-
rajma, though on a much smaller scale, which he discovered further
south on the continent. Mr. Wells was kind enough to show me a
series of his sketches of these mountains and the country surrounding
them. Not only was the similarity of the mountains to Roraima
striking, but I was also much struck by some sketches of places exactly
corresponding to what I have described as Epp el lings. Mr. Wells,
while disclaiming all botanical knowledge, assures me that the vegeta-
tion of his group does not correspond with that of Roraima.



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Notes on Plants at Roraima. 163

rock which constitutes the greater part of its surface,
clothed with a dwarf herb-like vegetation of most remark-
able appearance, consisting largely of various species of
P&palantkus, a Drosera, a few terrestrial orchids —
these not very conspicuous in flower — , a remarkable low
growing aloe-like Abolboda of which I shall have more
to say hereafter, various ground-clinging shrubs, of
Alpine, vaccinium-like, character, and of a very few
single shrubs, all of one species \Bonnetia Roraimae
Sp. N. OLIVER No. 330], of larger growth, though even
this is but some three feet high.

Nor in this brief sketch of the physical features of
Roraima in their bearing on the vegetation is it possible
to avoid mention of the great moisture of the atmosphere
which surrounds the mountain. The shallow basin of the
upper plateau ever holds much water, and probably at
times is almost full ; the sides of the cliff are ever mois-
tened by the innumerable rills and streams poured down
from the plateau above to the sloping base ; and this
basal portion itself is, on the more level, undulating
parts of its exposed surface, a mere spongy swamp,
while in its forested parts it is traversed by almost
innumerable rills hastening down to join the large rivers
of the plain below.

As when dealing with the vegetation along our line of
march to Roraima I pointed out that I could only pretend
to speak of the plants actually along that line, so in now
dealing with the vegetation of Roraima itself I can only
speak of that of the south-eastern side of this mountain,
which alone I was able to examine closely. We spent
nearly a month on this side, where it is comparatively
treeless, savannah-like and swampy; and we climbed to

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164 TlMEHRI.



the top of the mountain by a ledge running- obliquely up
this south-eastern face of its cliff.

It was not till we reached the top that we saw
the most remarkable features in the wonderful plant-
iife of this very distinft area of vegetation ; but
even while only approaching the base of the moun-
tain, which for convenience of description I will take
to be marked, on the south-eastern side, by the bed
of the Kookenaam river, and while we were still far
off wfc saw for the first time plants which Ave after-
wards found commonly on Roraima — the out-posts, as
k were, of the remarkable group of plant-forms centred
oil Roraima. And from the moment when the first of
these (Jistinflive plants of the mountain was met with
till the moment, some weeks later, when we reached the
top we ever travelled onward into a more and more
peculiar flora.

Our discovery on the savannah, a full day's jdurney
from Roraima, of the first out-post of the vegetation of
that mountain was a very distinft event. We found a
well-marked dense patch, perhaps some 40 yards in
diameter, of Abolboda sceptrum, nov. sp. OLIVER,
[No. 312], a compaft and dwarf, yucca-like plant — a
rosette, perhaps a foot and half in diameter, of most
acutely needle-pointed leaves. This plant appeared
again in patches once or twice before we reached Ro-
raima, and formed much of the turf, as it were, both of
the savannah slope of the base of that mountain and also
<m the top. Wherever it appeared, it was a constant
source of annoyance and of danger, not only to the naked
feet of my Indian companions, hut also to our own can-
vas-ctad feet. Luckily, a rumour Which in some, way



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Notes on Plants at Roraima. 165

spread among us that these rosettes of vegetable*
bayonets were poisonous, after causing some rather
comic alarm, proved groundless. Where we first found
the plant, as also on the sloping base of the mountain,
it was out of flower, and though its withered flower-stems
were extant, was even already seedless ; but on the top
we found it in full and striking flower. From the centre
of the rosette of leaves rises a single stem, perhaps
eighteen inches in height, crowned by a very regularly
formed whorl of dependent yellow flowers. The general
appearance — the fades > to use a term recognized by botan-
ists — was remarkably like that of the yellow form of the
Crown Imperial {Fritillaria imperialis). For the botan-
ical description of this interesting plant, as indeed of all
the other new plants of which 1 shall attempt to describe
the fades, I must refer to the list carefully worked out
at Kew. *

After passing the first station of Abolboda sceptrum,
till we reached the aftual foot of Roraima, at the bed of
the Kookenaam river, we continued through' a country
over which, though it was still furnished chiefly with the
ordinary savannah vegetation, were scattered a few
new plants ; and indeed as we advanced we met with
an ever increasing number of these. Across this traft,
about half-way between the station of Abolboda and
the Kookenaam, flows the Arapoo river, which, falling
down from Roraima. has its course marked in a

* It may be here mentioned that three volumes of admirable original
sketches of British Guiana plants made under the direction of (Sir
Robert?) Schomburgk exist in the Herbarium of the British Museum.
Among these sketches are to be found many Roraima plants, and,
among others, Abolboda sceptrum.



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166 TlMEHRI.



pronounced way by plants chara6teristic of that moun-
tain, such as Marcetia taxifolia Tr. [No. 68], Cassia
Roraimae, Bth. [No. 71], Dimorphandra macrostachya,
Bth. [No. 39], Meissneria microlicioides Ndn. [No. 174],
Calea ternifolia ) Oliver, N. sp. [No. 27]. To me the
most interesting plant on this river was a very beau-
tiful little slipper orchid (Selenipedium Klotzschianum y )
Reich, fil. [No. 31], which grew in the moist gravel of
the river bed, where the plants must frequently be
under water. This plant we also found in great abund-
ance on an island in the Cotinga river, another of the
Roraima rivers, and on a small creek, called A rote, a
tributary of the Cotinga. Naturally the Arapoo river,
as are its fellows flowing from Roraima, is an artery
allowing of the dissemination of plants from that moun-


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