PDF - Wallace Online

n EQUATORIAL VEGETATION 253parts of the world might occupy a volume ;but the precedingsketch will serve to give an idea of how important a part isfilledby this noble family of plants, whether we regard themas a portion of the beautiful vegetation of the tropics, or inrelation to the manners and customs, the lives and the wellbeing,of the indigenous inhabitants.FernsThe type of plants which, next to palms, most attractsattention in the equatorial zone is perhaps that of theferns, which here display themselves in vast profusion andvariety. They grow abundantly on rocks and on decayingtrees ; they clothe the sides of ravines and the margins ofstreams ; they climb up the trees and over bushes ; they formtufts and hanging festoons among the highest branches.Some are as small as mosses, others have huge fronds eight orten feet long, while in mountainous districts the most elegantof the group, the tree-ferns, bear their graceful crowns onslender stems twenty to thirty, or even fifty feet high. It isthis immense variety rather than any special features thatcharacterises the fern -vegetation of the tropics. We havehere almost every conceivable modification of size, form of.fronds, position of spores, and habit of growth, in plants thatstill remain unmistakably ferns. Many climb over shrubsand bushes in a most elegant manner ;others cling closelyto the bark of trees like ivy.The great birds'- nest fern(Platycerium) attaches its shell-like fronds high up on thetrunks of lofty trees. Many small terrestrial species havedigitate, or ovate, or ivy -shaped, or even whorled fronds,resembling at first sight those of some herbaceous floweringplants. Their numbers may be judged from the fact that inthe vicinity of Tarrapoto, in Peru, Dr. Spruce gathered twohundred and fifty speciesof ferns, while the single volcanicmountains of Pangerango in Java (ten thousand feet high) issaid to have produced three hundred species.Ginger-worts and wild BananasThese plants, forming tlie families Zingiberaceae andMusacese of botanists, are very conspicuous ornaments of theequatorial forests, on account of their large size, fine foliage,