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I have left Cypripediums to the last, in these hasty notes,
because that supremely interesting genus demands more than a record of dry
facts. Darwin pointed out that Cypripedium represents the primitive form of
orchid. He was acquainted with no links connecting it with the later and more
complicated genera; some have been discovered since that day, but it is
nevertheless true that "an enormous extinction must have swept away a multitude
of intermediate forms, and left this single genus as the record of a former and
more simple state of the great orchidacean order." The geographical distribution
shows that Cypripedium was more common in early times—to speak vaguely—and
covered an area yet more extensive than now. And the process of extermination is
still working, as with other primitive types.
Messrs. Veitch point out that although few genera of plants are scattered so
widely over the earth as Cypripedium, the species have withdrawn to narrow
areas, often isolated, and remote from their kindred. Some are rare to the
degree that we may congratulate ourselves upon the chance which put a few
specimens in safety under glass before it was too late, for they seem to have
become extinct even in this generation. Messrs. Veitch give a few striking
instances. All the plants of Cyp. Fairieanum known to exist have sprung from
three or four casually imported in 1856. Two bits of Cyp. superbiens turned up
among a consignment of Cyp. barbatum; none have been found since, and it is
doubtful whether the species survives in its native home. Only three plants of
Cyp. Marstersianium have been discovered. They reached Mr. Bull in a
miscellaneous case of Cypripediums forwarded to him by the Director of the
Botanic Gardens at Buitzenzorze, in Java; but that gentleman and his successors
in office have been unable to find another plant. These three must have reached
the Gardens by an accident—as they left it—presented perhaps by some Dutchman
who had been travelling.
Cyp. purpuratum is almost extinct at Hong Kong, and is vanishing fast on the
mainland. It is still found occasionally in the garden of a peasant, who, we are
told, resolutely declines to sell his treasure. This may seem incredible to
those who know the Chinaman, but Mr. Roebelin vouches for the fact; it is one
more eccentricity to the credit of that people, who had quite enough already.
Collectors expect to find a new habitat of Cyp. purpuratum in Formosa when they
are allowed to explore that realm. Even our native Cyp. calceolus has almost
disappeared; we get it now from Central Europe, but in several districts where
it abounded the supply grows continually less. The same report comes from North
America and Japan. Fortunate it is, but not surprising to the thoughtful
observer, that this genus grows and multiplies with singular facility when its
simple wants are supplied. There is no danger that a species which has been
rescued from extinction will perish under human care.
This seems contradictory. How should a plant thrive better under artificial
conditions than in the spot where Nature placed it? The reason lies in that
archaic character of the Cypriped which Darwin pointed out. Its time has
passed—Nature is improving it off the face of the earth. A gradual change of
circumstances makes it more and more difficult for this primitive form of orchid
to exist, and, conscious of the fate impending, it gratefully accepts our help.
One cause of extermination is easily grasped. Cypripeds have not the power of
fertilizing themselves, except a single species, Cyp. Schlimii,
which—accordingly, as we may say—is most difficult to import and establish;
moreover, it flowers so freely that the seedlings are always weak. In all
species the sexual apparatus is so constructed that it cannot be impregnated by
accident, and few insects can perform the office. Dr. Hermann Muller studied Cyp.
calceolus assiduously in this point of view. He observed only five species of
insect which fertilize it. Cyp. calceolus has perfume and honey, but none of the
tropical species offer those attractions. Their colour is not showy. The
labellum proves to be rather a trap than a bait. Large insects which creep into
it and duly bear away the pollen masses, are caught and held fast by that sticky
substance when they try to escape through the lateral passages, which smaller
insects are too weak to force their way through.
Natural hybrids occur so rarely, that their existence is commonly denied. The
assertion is not quite exact; but when we consider the habits of the genus, it
ceases to be extraordinary that Cypripeds rarely cross in their wild state.
Different species of Cattleya, Odontoglots, and the rest live together on the
same tree, side by side. But those others dwell apart in the great majority of
cases, each species by itself, at a vast distance perhaps from its kindred. The
reason for this state of things has been mentioned—natural laws have
exterminated them in the spaces between, which are not so well fitted to
maintain a doomed race.
Doubtless Cypripeds rarely fertilize—by comparison, that is, of course—in their
native homes. The difficulty that insects find in performing that service has
been mentioned. Mr. Godseff points out to me a reason far more curious and
striking. When a bee displaces the pollen masses of a Cattleya, for instance,
they cling to its head or thorax by means of a sticky substance attached to the
pollen cases; so, on entering the next flower, it presents the pollen outwards
to the stigmatic surface. But in the case of a Cypriped there is no such
substance, the adhesive side of the pollen itself is turned outward, and it
clings to any intruding substance. But this is the fertilizing part. Therefore,
an insect which by chance displaces the pollen mass carries it off, as one may
say, the wrong side up. On entering the next flower, it does not commonly
present the surface necessary for impregnation, but a sterile globule which is
the backing thereof. We may suppose that in the earlier age, when this genus
flourished as the later forms of orchid do now, it enjoyed some means of
fertilization which have vanished.
Under such disadvantages it is not to be expected that seed capsules would be
often found upon imported Cypripeds. Messrs. Veitch state that they rarely
observed one among the myriads of plants that have passed through their hands.
With some species, however, it is not by any means so uncommon. When Messrs.
Thompson, of Clovenfords, bought a quantity of the first Cyp. Spicerianum which
came upon the market, they found a number of capsules, and sowed them, obtaining
several hundred fine plants. Pods are often imported on Cyp. insigne full of
good seed.
In the circumstances enumerated we have the explanation of an extraordinary
fact. Hybrids or natural species of Cypripediums artificially raised are
stronger than their parents, and they produce finer flowers. The reason is that
they get abundance of food in captivity, and all things are made comfortable for
them; whilst Nature, anxious to be rid of a form of plant no longer approved,
starves and neglects them.
The same argument enables us to understand why Cypripeds lend themselves so
readily to the hybridizer. Darwin taught us to expect that species which can
rarely hope to secure a chance of reproduction will learn to make the process as
easy and as sure as the conditions would admit—that none of those scarce
opportunities may be lost. And so it proves. Orchidaceans are apt to declare
that "everybody" is hybridizing Cypripeds nowadays. At least, so many persons
have taken up this agreeable and interesting pursuit that science has lost count
of the less striking results. Briefly, the first hybrid Cypripedium was raised
by Dominy, in 1869, and named after Mr. Harris, who, as has been said, suggested
the operation to him. Seden produced the next in 1874—Cyp. Sedeni from Cyp.
Schlimii × Cyp. longiflorum; curious as the single instance yet noted in which
seedlings turn out identical, whichever parent furnish the pollen-masses. In
every other case they vary when the functions of the parents are exchanged.
For a long time after 1853, when serious work begun, Messrs. Veitch had a
monopoly of the business. It is but forty years, therefore, since experiments
commenced, in which time hundreds of hybrids have been added to our list of
flowers; but—this is my point—Nature has been busy at the same task for unknown
ages, and who can measure the fruits of her industry? I do not offer the remark
as an argument; our observations are too few as yet. It may well be urged that
if Nature had been thus active, the "natural hybrids" which can be recognized
would be much more numerous than they are. I have pointed out that many of the
largest genera show very few; many none at all. But is it impossible that the
explanation appears to fail only because we cannot yet push it far enough? When
the hybridizer causes by force a fruitful union betwixt two genera, he seems to
triumph over a botanical law. But suppose the genera themselves are artificial,
only links in a grand chain which Nature has forged slowly, patiently, with many
a break and many a failure, in the course of ages? She would finish her work bit
by bit, and at every stage the new variety may have united with others in
endless succession. Few natural hybrids can be identified among Cattleyas, for
instance. But suppose Cattleyas are all hybrids, the result of promiscuous
intercourse among genera during cycles of time—suppose, that is, the genus
itself sprang from parents widely diverse, crossing, returning, intercrossing
from age to age? It is admitted that Cypripedium represents a primeval
form—perhaps the primeval form—of orchid. Suppose that we behold, in this
nineteenth century, a mere epoch, or stage, in the ceaseless evolution? Only an
irresponsible amateur could dare talk in this way. It would, in truth, be very
futile speculation if experiments already successful did not offer a chance of
proof one day, and others, hourly ripening, did not summon us to think.
I may cite, with the utmost brevity, two or three facts which—to me
unscientific—appear inexplicable, unless species of orchid were developed on the
spot; or the theory of special local creations be admitted. Oncidium cucullatum
flourishes in certain limited areas of Peru, of Ecuador, of Colombia, and of
Venezuela. It is not found in the enormous spaces between, nor are any Oncidiums
which might be accepted as its immediate parents. Can we suppose that the winds
or the birds carried it over mountain ranges and broad rivers more than two
thousand miles, in four several directions, to establish it upon a narrow tract?
It is a question of faith; but, for my own part, I could as soon believe that
æsthetic emigrants took it with them. But even winds and birds could not bear
the seed of Dendrobium heterocarpum from Ceylon to Burmah, and from Burmah to
Luzon in the Philippines; at least, I am utterly unable to credit it. If the
plants were identical, or nearly, in their different habitats, this case would
be less significant. But the D. heterocarpum of Ceylon has a long, thin
pseudo-bulb, with bright yellow flowers; that of Burmah is short and thick, with
paler colouring; that of Luzon is no less than three feet high, exaggerating the
stature of its most distant relative while showing the colour of its nearest;
but all, absolutely, the same botanic plant. I have already mentioned other
cases.
Experience hitherto suggests that we cannot raise Odontoglossum seedlings in
this climate; very, very few have ever been obtained. Attempts in France have
been rather more successful. Baron Adolf de Rothschild has four different
hybrids of Odontoglossum in bud at this present moment in his garden at
Armainvilliers, near Paris. M. Moreau has a variety of seedlings.
Authorities admit now that a very great proportion of our Odontoglossums are
natural hybrids; so many can be identified beyond the chance of error that the
field for speculation has scarcely bounds. O. excellens is certainly descended
from O. Pescatorei and O. triumphans, O. elegans from O. cirrhosum and O. Hallii,
O. Wattianum from O. Harryanum and O. hystrix. And it must be observed that we
cannot trace pedigree beyond the parents as yet, saving a very, very few cases.
But unions have been contracting during cycles of time; doubtless, from the laws
of things the orchid is latest born of Nature's children in the world of flora,
but mighty venerable by this time, nevertheless. We can identify the mixed
offspring of O. crispum Alexandræ paired with O. gloriosum, with O.
luteopurpureum, with O. Lindleyanum; these parents dwell side by side, and they
could not fail to mingle. We can already trace with assurance a few double
crosses, as O. lanceans, the result of an alliance between O. crispum Alexandræ
and O. Ruckerianum, which latter is a hybrid of the former with O. gloriosum.
When we observe O. Roezlii upon the bank of the River Cauca and O. vexillarium
on the higher ground, whilst O. vexillarium superbum lives between, we may
confidently attribute its peculiarity of a broad dark blotch upon the lip to the
influence of O. Roezlii. So, taking station at Manaos upon the Amazons, we find,
to eastward, Cattleya superba, to westward C. Eldorado, and in the midst C.
Brymeriana, which, it is safe to assume, represents the union of the two; for
that matter, the theory will very soon be tested, for M. Alfred Bleu has "made
the cross" of C. superba and C. Eldorado, and its flower is expected with no
little interest.
These cases, and many more, are palpable. We see a variety in the making at this
date. A thousand years hence, or ten thousand, by more distant alliances, by a
change of conditions, the variety may well have developed into a species, or, by
marriage excursions yet wider, it may have founded a genus.
About Orchids
About Orchids, 1893
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