The beginnings of the orchid family are shrouded in mystery. Since most orchids are epiphytic—that is, having aerial roots through which they receive sustenance from the minerals in the moisture-laden air of the tropics—they have left no traces such as the fossilized remains of ground-growing plants. Dr. E. Soysa, writing in Orchid Culture in Ceylon, advances the delightful and plausible, if unproved, theory that orchids antedated the fossil era, but in their love of light ascended trees to escape the advanc­ing jungle. There they lived, died, dried up, and floated away, leaving no trace. Whatever the genesis of the orchid family, it cannot be doubted that the orchid family is very old, judging both by its great variety and its highly complex structural develop­ment, attainable only through the passage of time.

The orchid is among the largest and most highly developed of the plant families, with some fifteen to twenty thousand species. A provident nature has lavished every means to insure the per­petuation of this favorite child. She has provided the flower with all the charm and allure of a fairy princess to win insect vassals to perform the service of cross-pollination. Nature has decreed that the orchid should be dependent on some outside insect agent, and the resultant relation is a beautiful example of co­operation between the plant and animal kingdoms. The highest means of perpetuation in plants, cross-pollination is necessary in all but a very few species of orchids. In the few cases of self-pollination the seeds are frequently infertile.

The insects performing the service of cross-pollination vary with the species and are as diverse as the ingenious contrivances by which the orchids utilize them. It is in every case a reciprocal arrangement, the plant receiving the benefits of fertilization, the insect the largess of food and drink. Each species usually has its particular insect, as is shown by the special means each flower uses to attract its insect.

Darwin first noted a striking example of this specialization. On a trip to South America he had an opportunity to see a plant of Angraecum sesquipedale. This starry-white flower, a rare orchid of Madagascar, has a weirdly elongated lip containing a nectary, about eleven inches long, that holds one-and-a-half ounces of the sweet fluid produced by the sugar-secreting glands. Darwin im­mediately predicted that some day a moth with a proboscis at least twelve inches long would be discovered to be responsible for cross-pollination of this peculiar orchid. In time such a moth was found and was duly named Xanthopan morgani praedicta. In this particular alliance it is probable that the moth would starve without the orchid and that the orchid would become extinct without the moth. Such high specialization has insured the purity of species that has marked the progress of the orchid family.

This specialization is reflected in the extremely varied forms of the reproductive organs. These organs lie within the lip, more scientifically known as the labellum, along a fleshy enlargement called the column. The anther-bearing stamens are usually sealed together into the column, and a projection of this elongated fleshy organ is the rostellum, whose purpose seems to be to sep­arate the pollen and the stigmatic cavity, thus minimizing the danger of self-pollination. The anthers produce tiny powdery grains of fertile pollen, usually held together by a mysterious viscid fluid that hardens on exposure to air and is not affected by wind or rain. The stigmatic cavity with its receptive ovum (egg) waits for the 'marrying' insect to deposit pollen from another flower.

The labellum serves in three capacities: it provides storage space for the pollen, an antechamber to the ovary, and a banquet room for the insect. On entering any orchid flower the insect must first brush the empty stigmatic cavity in his search for the nectar or other food. Drunk with the repast, he blunders out, the narrow passage compelling him on the way to brush past the pollen masses, which become dislodged and, because of the sticky fluid, adhere to him. These masses hold firmly until he enters another flower of the same species. The feeding position is ideal for de­positing the pollen.

In some species the insect is not allowed to enter the storage chamber but, by lighting on the labellum, he releases a tiny gun that projects the pollen masses toward him in the shape of a blunt arrow. With this attached to his body he flies to the next flower where, as he sups, the arrow of pollen fits neatly into the cavity. He probably picks up another load of precious pollen as he leaves, and hunger, or perhaps the memory of his recent feast, leads him again to the proper flower, where he once more deposits his burden.

Most flowers offer nectar but some offer solid food to the insect performing the pollination service. Insects have been observed feeding on the crest, a crisp ridge on the labellum. Some pervade the air with perfume, while others bring visitors by their hand­some size and showy color. Small inconspicuous flowers cluster together on the stems to win attention. Some wear shining white that gleams in the moonlight and draws night-flying moths.

Once arrived at the flower, the insect's path is not left to chance but is carefully charted. Lines on the lip lead inward, crests are raised to keep his steps from straying, dark spots on the bright throats, or the large white spots common to some species and called 'eyes,' act as beacons. Although the flowers differ in their insect-attracting characteristics, there is one feature common to all: the insect must always pass the empty receptive stigmatic cavity first, thus depositing his load of pollen before feeding and picking up more pollen.

In most of the flowers the exaggerated labellum twists from normal to flatten out and form a welcome mat to the feast within. After pollination, this mat is lifted or twisted back to normal to prevent further intrusion. The ovary lies just behind the column and part-way down the stem. After pollination the male pollen cells travel down a long passage to fertilize the waiting egg. This requires a period of twenty-four hours or longer, and sometimes fails entirely. If fertilization has taken place, the ovary begins to swell and the fruit or seed pod begins to form below the flower. Maturation will require from nine to eighteen months, depending on the species. Seeds require five to seven years or more to pro­duce blooming plants, although some of the so-called 'botanicals' may require less.

Beauty and use seem to go hand-in-hand in the orchid family. The lovely petals and sepals of the flowers guard and protect the vital organs hidden in the labellum: in some cases as extra pro­tection they never entirely open, and in others they fold as soon as the flower has been pollinated. This last evidence of protection often comes as a shock to the amateur orchid grower. When an uninvited bee enters the greenhouse and pollinates a bloom being cherished for a special exhibit, the flower responds by blushing violently and soon thereafter folds its petals or 'wilts,' much to the distress of the grower.

Nature's schemes for perpetuation of the orchid species work with wonderful precision. A peculiar balance seems to be observed in that rarer and less productive orchids have developed a more complicated and thus more accurate and certain method of cross-pollination. Self-pollination is discouraged by nature. Even in the few orchids capable of it, the process seems only to be used when insects fail to appear.

The process of pollination is comparatively simple in genera with large, open flowers, having short, fairly wide, easily acces­sible nectaries as, for example, Cattleya, Laelia, Phaius, Sophro-nites, Bletia, Coelogyne, and Cymbidium. Bees readily perform the service. In greenhouses with wide-open vents the bees frequently pollinate indiscriminately and many wilted flowers result. Those having a longer nectary, like the Angraecum, are pollinated by moths. Members of the genus Vanda and perhaps of Aerides are probably pollinated by a larger moth. Some of these that produce only a few flowers also manufacture extremely firm cement for attaching the pollen masses to the insect, preventing loss in flight. Certain types of Cypripediums are attractive only to small bees. Epipactus latifolia finds its needs best served by wasps.

Darwin reported that a Dr. Criiger had observed swarms of bees actually feeding on the crests of the labellum of Coryanthes, a weird flower with a hooded dorsal that appears to crouch down over the labellum. Its most interesting characteristic is a bucket-shaped appendage peculiar to the species. This is filled with a slow-dripping fluid, not a nectar, whose purpose seems to be to wet the wings of the hungry bee when he passes the slippery sides and thus force him to creep through a narrow passage. Here he forcibly brushes the stigmatic cavity, finds crests spread for him to nibble, and picks up the pollen while feeding. He flies off and repeats the process on another Coryanthes and the cycle is com­pleted.

In Pterostylus, after the insect enters, the labellum shuts a little trap door, forcing him to leave by the back through a passageway where the cramped quarters facilitate the performance of his function. Masdevallia fenestra never fully opens but has tiny windows that remain open until pollination occurs, when they are drawn shut. Darwin admitted that he was never able to de­termine the method of pollination for this flower.

As amazing as are these structural oddities, they are no more so than the means by which the pollen masses adapt themselves to a position suited to their proper delivery. Rutherford Platt in This Green World has reported that the Orchis, fertilized by bees, attaches the pollen masses to the bee in erect horns, which, however, wilt down in a manner that permits them to hit exactly the waiting cavity of the next flower. If they remained erect they would not fit.

Calopogon carries its stigma on the bottom part of the petal, and when the bee lands with a pollen load he is neatly flip-flopped into a somersault that brings the pollen on his back to proper contact. In Cypripedium acaule the bee is attracted to the en­trance by white lines, pushes through the softly drawn drapes of the pouch of the 'lady's slipper,' and sips the nectar, but when he seeks to retreat, the drapes are closed tight behind him. By squeezing through the only open place, the hole at the top, he first scrapes the pollen on to the stigma and then, pushing past the pollen masses at the top, picks up another load. Apparently undaunted he flies to another rosy slipper and repeats the routine.

In Catasetum the vital pollen is stored in a secret chamber inaccessible to the visitor and, as already described, is discharged by a miniature catapult at the intruding insect. Most interesting of orchids, Catasetum appears to be an exclusively male form, and Momtchanthus viridis, which has only rudimentary pollen masses, the female of the same species.

The pollination of orchids is a subject that still has ample room for original research. Far too little is known about the subject. Are the so-called spider orchids (Cryptostylis arachnitis) fertilized by spiders, the Arachnis muscifera, resembling flies, by flies, and the bee orchids (Bee Ophrys) by bees? Is it the putrid smell of Bulbophyllum putridum, or foetidum, that attracts, and are the attracted insects those that feed on decayed vegetable matter? Patient and close observation will be needed to discover the answers.

In addition to the great variety of inducements and ingenuity of nature to insure pollination, the orchid plant, compensating for the extreme danger threatening its very tiny and powdery seed progeny, produces this seed in great profusion. Darwin cited an instance of one pod with approximately 6,020 fertile seeds, the plant bearing four such capsules. One plant of Orchis maculate produced thirty seed pods, each pod containing about 6,200 seeds, or a total of 186,300. Fritz Miiller found 1,756,440 seeds in a single Maxillaria pod. The world would be overrun by orchids were it not that the seed prospers under conditions that are equally favorable to its enemies, pests and fungi. The orchid seed's chance for survival is further reduced by the fact that it is not in itself supplied with sufficient food but must depend on outside help—a friendly fungus called Rhizoctonia, supplanted in artificial cultivation by chemical nutrient. Another important dis­advantage of the orchid seed is that, as compared to other plants, it is singularly undifferentiated into roots, leaves, and endosperm.

The matter of propagation is of utmost concern to the grower. Propagating from seed, which will be considered in a later chap­ter, is a rather technical method for beginning amateurs, but other methods of propagation, either natural or artificial, seem prosaic compared to the thrilling story of seed production and seed growing. In some ways, however, they are more advanta­geous, in that they are simpler and produce a flower of certain appearance.

Plants of sympodial growth, that is with the new growth coming out of the base of and alongside the old bulbs, will be found to propagate readily by division. Cattleya, Laelia, and Cym-bidium are typical of this type. Cypripedium is frequently found to divide itself in nature even more readily than others of the type.

The Cattleya permits division as long as three or four bulbs are allowed. Each year in the life of the Cattleya adds a new growth at the front end of the plant, and certain species may occasionally grow in two and, more rarely, in three directions. As the new bulbs form, the old ones frequently begin to lose their leaves and roots. They become 'poor relations,' a drag on the living plant. On being severed from the living plant the backbulbs, as these old drybulbs are called, will, if placed in a warm, moist spot, start life over. After two, three, or perhaps four years these will be new plants and will flower. The advantage of the backbulb type of propagation over the growing of seedlings is that the flower will exactly resemble that of the original plant, while in the seedling there is no way to tell whether it will resemble one parent plant or the other or be something entirely different.

Plants of monopodial growth, like Vanda, Renanthera, and Angraecum, with the new growth appearing continuously from the top or crown, will not divide so readily. The only method of propagation for them, other than seed growing, is to cut off the top of the plant below several of the husky aerial roots. On being potted, the top part may take root and become a new plant. It is a risky practice, however, and is not especially recommended to amateurs unless for some reason the crown of the plant has become damaged and appears dead. When the top is cut off or injured in this fashion the bottom part will probably develop adventitious plants. This type of plant is a slow grower and needs to be very large before flowering, so that any kind of propagation is a slow and tedious process at best.

Phalaenopsis, while differing from Vanda in that it is stemless, is also of monopodial growth and not divisible. It will occasion­ally throw adventitious plants from the nodes of the flower stem. Experiments have shown that it is possible, by wrapping the flower node in damp Osmunda and keeping it warm and damp, to force the growth of a new plant.

Dendrobium, of sympodial growth, will put forth little plant-lets, complete with bulb and roots, at the slightest provocation. These plantlets develop from the cane-like flower stems. If the beginner keeps his Dendrobiums, especially the deciduous type, too warm and moist during the dormant season they will waste their strength in plantlets and fail to bloom. Many commercial growers pick the entire cane on flowering and, after cutting off the blooms, lay the canes on damp, warm sand or gravel to allow plantlets to develop from the dormant eyes. Dendrobiums are easily divided or grown from seed.

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