Año
22. Nº 2
Año
22. Nº 2
REMARK UPON THE ORQUIDEOUS PLANTS OF CHILE
John Lindley
Much has been done in investigating the vegetable productions of South America, it must be confessed that we still are far from processing any definite notion of the botany of that vast continent. But if this be true of the South America Flora in general, it is much more so with respect to the more southern provinces, and especially with regards to Chile. The number of plant recorded in scientific works, as natives of that region, are so few compared with what from analogy it may be presumed to contain, that is botany may be considered almost entirely unknown. It is true, indeed, that a very considerable addition to the published list of Chilean plants might be made from an examination of certain private herbaria; but as far has the scientific world in general is concerned, the statement above made is strictly accurate.
From the copious materials relating to the vegetation of Chile which exist in this country, much information of the most important nature is derived; but from no source so extensively, perhaps, as from the collection formed for the Horticultural Society by Mr. James Mc Rae. From these I have selected the highly curious tribe of Orquideous plants as the subject of the following remarks.
The distribution of Orchideĉ with respect to the surface of the globe, is one which has hitherto scarcely occupied the attention of geographical botanist; not can our notions respecting it, for some time to come, be expected to acquire any considerable degree of accuracy. So much difficulty exist in preserving dried specimens of this tribe of plants, and in the determination of them when preserved, that, with the exception of Europe and North America, we can form no conception of the proportion that they bear to the Flora of the world, or of the relation which the form of one Flora bear to those of another.
A few striking facts appear, however, to be ascertained, which may serve as the basis of future observation; and which are well worthy of consideration, as they seem to indicate between the minute parts of the structure of Orchideae, and their general economy, a close connection which is not at present susceptible of explanation.
In a extra-tropical countries, where the species grows on the earth among grassy herbage and are supported by fleshy or fasciculate roots, the greatest number belong to genera with decompound pollen-masses, or, more correctly speaking, with their pollen in a very incomplete state of cohesion; - those with solid pollen masses and glandular appendages either no existing at all, as in Europe and the North of Asia, or constituting not more than a thirteenth part of the whole, as in North America, and, perhaps, the Cape Of Good Hope; and those with solid pollen, without appendages, not exceeding that proportion, or being altogether unknown, as in the southern point of Africa. Within the tropics this order seems to be reversed: there the species are, for the most part, found upon trees, or growing on decaying woods, their roots are no longer fasciculate and fleshy, and fitted for deriving sustenance from the earth, but filiform and dry, and adapted to clinging to foreign bodies for support and nutriment; in this the pollen is solid, and generally fitted with a glandular apparatus. But whether in intra or extra-tropical countries, it seems to be a general law that species are everywhere to be found with their pollen and collumna in five at least of the seven different modifications of which organs are susceptible. In this I do not include Cypripedium, which is a genus altogether with a peculiar character, and only know in the Northern Hemisphere.
To the law just stated I am aware of only two exceptions --both very remarkable; the one being the Cape of Good Hope, and the other Chile. In Southern Africa, the Orquideĉ consist entirely of Ophrydeĉ, but of a structure quite peculiar to that promontory; there is only one Neottiea and a very few Vandeĉ. The genera are all strictly what Mr. De Candolle calls endemical; they are numerous and extremely dissimilar to the one from the other, while no immediate affinity is to be traced between them and the genera of other districts, except the isles of France and Madagascar, and the more equinoctial district of African Continent. Upon the whole whatever peculiarity may be found in the Colony of the Cape of Good Hope as to the genera which inhabit it, there are no great deviation from the general proportion which genera and species bear to the surface of the district they occupy.
But with Chile the case is widely different. In this country, which, in the eyes of the botanical geographers, form a vegetative region of itself, -which extends through twenty degree of southern latitude, and which as a surface varied with all the irregularity of mountain covered with eternal snow, rich valleys, and extensive plains, no more than three species of Orquideĉ are at this moment recorded to exist, and this are known only by the figures and imperfect description of Feuillée.
To this number I have now to add nine new species, together with some observation upon the three previously recorded. Upon referring to the end of this remarks, it will be seen, that after taking into account both the published and unpublished species of Chilean Orquideĉ, that portion of the Flora comprehends only four genera, three belong to Arethuseĉ, the other Neottieĉ; and there is strong reason to believe that this is not the only Orquideous genera to be discovered in Chile, do constitute almost the entire feature of that part of vegetation which they represent; for among the extensive collection of drawings made by Mr. Miers, during a long and active residence in the country, I observed nothing to contradict such opinion. Of this Chloraea, Bipinnula and Asarca are absolutely confined to the province, and to that of Buenos Ayres; while Spiranthes is one of the most widely diffused of all know genera, species of it having been found in the temperate parts of Europe and Siberia, in Northern India and New Holland, in the islands of the Indian Archipelago and off the coast of Southern Africa, in North America and West Indies, in Brazil, and lastly, in Chile; in fine, there are not more than five of the twenty botanical region into which the surface on the globe is divided by writers upon botanical geography, in which Spiranthes is not known to exist; and analogy leads us to believe that in three of this five it will be found by future inquirers.
Is highly curious that the botanical affinities of Chloraea, Bipinnula and Asarca, the endemic genera of the province, are not so immediately with other South America genera as with those of New Holland. While the totally disagree with Stenorhynchus, Cranichis, Ponthieva, and Prescottia, all exclusively American genera they represent, on American Ground, the numerous tribes of Arethuseĉ peculiar to New Holland, and specially Liperanthus and Caladenia. Chloraea galeata has very much the appearance of the New New Holland Perostylis rufa in a gigantic state; and even Prasophyllum fimbriatum of the same country has a closely analogous structure with that of Bipinnula plumosa.
I now proceed to state the technical character and botanical history of the plant which are the subjects of these observations