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   This deservedly famous orchid was discovered in East Madagascar by Aubert Du Petit-Thouars (1758-1831), French botanist and traveler. His work on the orchids of Madagascar is the first illustrated monograph ever written on orchids.
   Original copies of this book are among the rarest orchid books and command astronomical prices today. It is such a rarity that not infrequently even prestigious orchidology books wrongly cite or at least truncate already the title of it, which reads in full as follows:
   Du Petit-Thouars, A. A.:
"Histoire particulière des plantes Orchidées receuillies sur les trois îles Australes d'Afrique, de France, de Bourbon et de Madagascar".   The book was published in Paris by A. Bertrand & Treuttel Wurtz, in 1822.
    It contains only 8 unnumbered plus 32 numbered pages text and there are 110 engraved plates (108 full page, two fold-outs) drawn and engraved beautifully by the author himself.
    The Angraecum generic name is derived from the Malaysian "Anggrek", which in the Indo-Malaysian Archipelago is used as a general term for epiphytes featuring thick roots. The Latin sesquipedalis means "one-and-half-foot long", referring to the prominent, up to 12-15 inches long, pendent spur of the flowers.
   The English vernacular names "Comet Orchid", "Christmas Star" or "The Star of Bethlehem Orchid" also allude to the star-shaped flowers and the long spur. The French common name, "l'Étoile de Madagascar" means the "Star of Madagascar" in English.
   Angraecum sesquipedale Thouars (1822.) is endemic to Madagacar and neigboring islands, where it is epiphytic on large trees or grows terrestrially in rocky grasslands of mountain slopes. This orchid became famous when Charles Darwin predicted that its natural pollinator must be a moth featuring a tongue which is matching the length of these extraordinary spurs.
   In Darwin's famous book titled "The Various Contrivances by which British and Foreign Orchids are Fertilised by Insects and on the Good Effects of Intercrossing" (Published in London by John Murray (1862.) the frequently referred to but by most of the referrers hardly if ever cited text runs as follows.
   "The Angraecum sesquipedale, of which the large six-rayed flowers, like stars formed of snow-white wax, have excited the admiration of travellers in Madagascar, must not be passed over. A green, whip-like nectary of astonishing length hangs down beneath the labellum. In several flowers sent me by Mr. J. Bateman I found the nectaries eleven and half inches long, with only the lower inch and a half filled with nectar.
   What can be the use, it may be asked, of a nectary of such disproportionate length? We shall, I think, see that the fertilisation of the plant depends on this length, and on nectar being contained within the lower and attenuated extremity. It is, however, surprising that any insect should be able to reach the nectar. Our English sphinxes have proboscides a long as their bodies; but in Madagascar there must be moths with proboscides capable of extension to a length of between ten and eleven inches! This belief of mine has been ridiculed by some entomologists, but we now know from Fritz Müller that there is a sphinx-moth in South Brazil which has a proboscis of nearly sufficient lenght, for when dried it was between ten and eleven inches long. When not protruded it is coiled up into a spiral of at least twenty windings."
  Then Darwin describes how he experimented with a "... a cylindrical rod one tent of an inch in diameter ..." to imitate the proboscis of a large moth and how he succeded in removing then attaching the pollinia to the stigma. Darwin was so elated by his success that the last, uninterrupted paragraph closing this subject became a stylistics monster running through more than one full page of the small format book.
    True to his form, here Darwin is highly anthropocentric and teleological again. Realizing his underlying presuppositions would call for supernatural mental abilities enabling living creatures to modify their genetically determined properties at will - by dreaming up and setting aims then undretaking transformations pointig towards specific goals. Of course in Darwin's time the biochemistry of genetical processes was absolutely unknown. Having said so, here comes a lengthy tirade on the supposed co-evolution of this orchid and at the time of writing still unknown giant moth:

   "If such great moths were to become extinct in Madagascar, assuredly the Angraecum would become extinct. On the other hand, as the nectar, at least in the lower part of the nectary is stored safe from the depredation of other insects, the extinction of the Angraecum would probably be a serious loss to these moths. We can thus understand how the astonishing length of the nectary had been acquired by successive modifications. As certain moths of Madagascar became larger through natural selection in relation to their general conditions of life, either in the larval state, or as the proboscis alone was lengthened to obtain honey from the Angraecum and other deep tubular flowers, those individual plants of Angraecum which had the longest nectaries (and the nectary varies much in some Orchids), and which, consequently, compelled the moths to insert their proboscides up to the very base, would be fertilised. These plants would yield most seed, and the seedlings would generally inherit long nectaries; and so it would be in successive generations of the plant and of the moth. Thus it would appear that there has been a race in gaining length between the nectary of the Angraecum and the proboscis of certain moths; but the Angraecum has triumphed, for it flourishes and abounds in the forests of Madagascar, and still troubles each moth to insert its proboscis as deeply as possible in order to drain the last drop of nectar."

   The speculations of Darwin based on his experiments concerning the existence of a giant moth in Madagascar were corroborated only eleven years later, when the indeed nocturnal hawk-moth, the pollinator of Angraecum sesquipedale was discovered and described for science no less than fifty-five years after Darwin's prediction. Since then the valid scientific name of this hawk moth is Xanthopan morganii praedicta Rothschild et Jordan (1903.), in honor of Darwin's prediction.
   Alas, so far neither Angraecum sesquipedale nor Xanthopan morganii praedicta seem to be aware of the genial breeding program Darwin devised for them. Which is a great pity because in that way their evolution remains exposed to the vagaries of unpredictable mutations - not controllable by occult powers at will ...
    The plant does not have pseudobulbs unlike many other of the orchids. Its leaves look like a large fan (see the bottom left quarter of the photo) and old specimens in nature may grow to be over one yard tall.

  The blossoms are star-shaped and reach up to 7" (17.8cm) in diameter. The blooms are a waxy white to greenish white in color.

   Each blossom also has a spur that begins at the bottom of the bloom which can reach over 12" (30.5 cm) in length. At the base of this spectacular spur is the sweet nectar that attracts the pollinator.

   Angraecum sesquipedale is a fairly easy orchid to grow, even in your windowsill. This orchid likes a little shade and no direct sun. Maintain day temperatures of 70-80 oF (21-27 oC) and night temperatures of 60-68 oF (16-20 oC).

  Keep the medium evenly moist and the humidity around 60%.

  Water less in the winter after flowering for a few months. Plant in baskets or pots with bark or other media that will provide good drainage.

   Fast grower this orchid is not but even fairly young and small, only 10-15 inches tall specimens start flowering if kept under suitable conditions.
Angraecum sesquipedale
 Angraecum sesquipedale with its pollinator, Xanthopan morganii praedicta. Scientifically correct illustration by S. Abonyi, 2006
   Sue Abonyi, our botanical illustrator artist friend recently on an inquiry from the Smithsonian National Museum of Natural History created the scientifically correct painting showing Angraecum sesquipedale and the famous moth Xantophan morganii predicta shown here.

   In contrast with numerous fantasy illustrations her work is based on careful measurements made on photos of the orchid including the photo above and photos of hard-to-find museum specimens of the moth and rendered true to scale.

   I am very pleased to show first time her awesome painting on-line for orchid enthusiasts.
 The painting will appear soon in a texbook by Professor Sungbin Imm of the Myongji University, South Korea.
Sue Abonyi's RB Portfolio Visit Sue's Website !
A Very Merry Christmas to all!