704 
THE VOYAGE OF H.M.S. CHALLENGER. 
by the waves, but they nevertheless have large woody fungi growing upon them, some- 
times attached so low down that they are frequently immersed in salt water. The 
overhanging branches are loaded with a thick growth of epiphytes ; and it was necessary 
to wade up to the middle in order to collect specimens of orchids and ferns which hung 
often only a couple of feet above the water. 
In other places the shore is swampy, and is either covered with mangroves or with a 
dense growth of high trees with tall straight trunks, so closely set that it was very 
sensibly dark beneath them. In such a grove near Pigeon Island, a small outlier near 
the anchorage, whilst the ground beneath is bare and muddy and beset with bare roots, 
the trunks of the trees and fallen logs are covered with a most luxuriant growth of feathery 
mosses and Jungermannias. 
On one of these trunks was found a very curious and rare Fern ( Trichomanes 
peltatum), known before only from Samoa and New Caledonia, the fronds of which are 
circular in form, and, connected by a slender rhizome, adhere in rows to the bark. They 
are pressed absolutely flat against the bark, so as to look like an adherent crust, and have 
all the appearance of a Riccia or some such liverwort, for which indeed they were 
mistaken, when gathered by shaving off the bark. A species of Adder’s-tongue Fern 
( Ophioglossum pendulum), unlike the humble little English form, grows in abundance 
attached to tree stems with long pendulous fronds a yard in length. 
Before the visit of the Challenger the botany of the Admiralty group was entirely 
unknown. Amongst the plants collected was a new tree-fern, and an orchid forming a 
new section of the genus Dendrobium. 1 
The morning after the Expedition arrived trade went on briskly, the canoes crowding 
round the ship, and the natives handing their weapons and ornaments through the main 
deck ports. The barter given in exchange was principally ordinary hoop iron broken up 
into pieces about 6 inches in length ; but a great quantity of so-called “ trade-gear ” 
was also disposed of. 
Trade-gear is regularly manufactured for Polynesian trading, and sold by merchants in 
Sydney and elsewhere. A stock of about £300 worth had been bought for the ship’s use. 
It consisted of a cask of small axes, rather worthless articles with soft iron blades, butcher’s 
knives of all sizes, some with blades 12 to 14 inches in length, Turkey red and navy blue 
cotton cloth, beads, trade tobacco and pipes, and other similar articles. 
The islanders had possibly traded with Europeans shortly before the Challenger’s 
visit, for they brought off their tortoiseshell ready done up in bundles, and knew the 
relative value of various qualities. The chief had a large European axe, apparently not 
procured from the ship, and many natives had hoop iron adzes. Nevertheless they must 
have had very little experience indeed, otherwise they would not have taken old German 
1 Bot. Chall. Exp., part iii., 1885. 
