But strange as these Broomrapes and Toothworts may be, they are quite inconspicuous as compared with the gigantic parasites found in Sumatra and Java.
In 1818, when Sir Stamford Raffles was making a tour in the interior of Sumatra, his party came across one of those extraordinary plants which have been called after him.
Imagine a gigantic flower in shape resembling a very fleshy forget-me-not, but more than a yard across! The colour is a livid, fleshy tint, and the smell is like that of a charnel-house. This extraordinary Rafflesia Arnoldii is the biggest flower in the world. It has no proper stems or leaves, but consists merely of this huge flower-bud attached to the roots of Figs, etc., which traverse the ground in these forests. It is said to be only found in places frequented by elephants, which are supposed to carry its seeds on their feet.
There are four other kinds known: all of them occur in Sumatra, Java, and other neighbouring islands. R. Padma for example, has a flower about eighteen inches across. The central part is a dirty blood-red, while the lobes have almost the colour of the human skin. This also has a "cadaverous smell, anything but pleasant."
These weird Rafflesias seated on the roots "which wind about on the dark forest ground" have impressed every observer.
Yet if one glances back, it is interesting to see how insensible are the transitional steps which lead from independent life by the plant's own exertions to these last "pure parasites," which are entirely dependent on other plants for everything that they require.
The only other flowering plant which we shall mention in this chapter is now fortunately very rare in Great Britain. This is the Dodder, Cuscuta. It belongs to the Convolvulus or Bindweed order, but is entirely different from the rest of the family. Some climbing plants do throttle or choke the trunks of young trees if they twine round them too closely, but the Dodder has an entirely special and peculiar way of supporting itself to the detriment of others. It has no roots, no leaves, and scarcely any green chlorophyll; the Dodder is just a twining, thread-like, yellowish stem which carries here and there small round clusters of little convolvulus-like flowers. Wherever the Dodder thread twines round a hop or other plant, it puts out small suckers which drive their way into the stem of the hop and take from it all the food which the Dodder requires. When well developed it forms dense yellowish tangles of intricately entwined threads, which may cover whole bushes and entirely destroy the supporting plants. The Flax, Clover, and Hop Dodders are perhaps the worst of them all.
There are some rather interesting points in the history of the tiny dodder-seedling. It remains, quietly waiting, for about a month after most other plants have germinated.
Then it begins to grow rapidly: its tip pierces the soil and becomes fixed in it; then the rest of the little thread-like seedling begins to curve round or revolve. If it touches a grass or even a nettle stem, it twines itself or coils round it, drives in its suckers, and, on the strength of the nourishment which it extracts, it goes on revolving or turning until it forms the dense tangled masses referred to.
Then an eruption of flowers appears, from which later on hundreds of tiny seeds are let loose which will become Dodders in their turn.