WILD FLOWERS OF THE BRITISH ISLES 
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in appearance that they are frequently likened to animals, reptiles, and insects, as we 
may see by their names, the Monkey-, Frog-, Lizard-, Bee-, Fly-, Spider-, and Butterfly- 
Orchids. 
But it is in the hot, moist climate of the tropics that these strange plants are seen at their 
best. There they do not root in the earth — their thick, contorted, grey, snake-like roots 
twine and twist in the branches of trees and huge ferns ; they are nearly leafless, and bear 
on slender stalks gorgeous and fantastical flowers, coloured and marked in marvellous fashion, 
and often filling the air with their sweet perfume. Though growing on trees they are not 
parasites ; they derive their food from the hot, damp air and from any decaying vegetable matter 
that may have collected round their roots — they are epiphytes. 
Not only are the flowers of such strange and exceeding beauty of form and construction, 
but they are marvellously planned with a view to fertilisation — usually with a definite intention 
of insect pollination, that is to say with the idea of insects carrying the pollen from one flower to 
another. The perianth always protects the column so as to allow the entrance of insects in such a 
way only as to remove the pollen. The pollen-masses, or pollinia as they are called, are attached 
to the column by a sticky gland, against which the insect brushes on entering the flower. This 
action ruptures a delicate membrane covering the sticky gland, and the gland with its pollen- 
bag adheres to the insect and separates from the column. While the insect is obtaining his 
store of honey the sticky matter sets as hard as cement, so that there is no chance of the 
pollen-bag being moved on the insect. This is not all, however, for if the pollen-bag remains in 
the same position it is clear that when the insect enters another flower the pollen will touch 
the stamen of that flower and not the stigma which is lower down on the column. This would 
be of no use, the end in view being the fertilisation of the stigma of the next flower entered. A 
wonderful mechanism is provided. The sticky gland, though now set as hard as a rock, has the 
power of contraction when exposed to the air, and from being upright on the insect the 
contraction of the gland bends the stalk of the pollen-mass downwards, into a position where, 
as the insect enters the next flower, the pollen strikes the stigmatic surface. Only a part of the 
pollen is torn off and one pollen-mass is able to fertilise many flowers. The nectar is not 
always free and easily obtained ; sometimes it answers the purpose of fertilisation better to delay 
the exit of the insect, and in these instances Darwin discovered that the honey was secreted 
between the layers of tissue which compose the tube, so that the outer tissue has to be pierced in 
several places before the nectar can be obtained, giving ample time for the sticky disk to set as 
hard as a rock. It is due primarily to Darwin’s researches that the exact mechanism of the 
orchid with regard to fertilisation has been made clear. In his “ Fertilization of Orchids ” the 
process is lucidly explained. 
Apart from the beauty of the flowers and wonder of construction, the orchid order is of 
little known use. The Vanilla (Vanilla planifolia), a native of Mexico, but now cultivated in 
all tropical countries, a species which climbs over walls and trees like our Ivy, produces capsules 
which are useful, when dried, as a flavouring in cookery. From another genus a gluey matter is 
extracted which is used in Brazil ; the roots of Eutophia vera and Eutophia campestris, natives of 
India, furnish Salep, as do two of our own orchids, Orchis mascula and Orchis Morio. Otherwise 
the attraction of the order lies in the weird beauty of the flowers. 
Some interesting tropical families — the Musaceae, Marantaceae, Cannaceae, and Zingiberaceae 
— frequently have only one fertile stamen, the others being like petals, and sometimes being 
united into a lip (labellum). Members of the first two mentioned orders are cultivated in 
tropical countries, such as the Banana (Musa sapientum), the Plantain (Musa paradisiaca), and 
