680 
THE VOYAGE OF H.M.S. CHALLENGER. 
and from 1^ ta 2 inches in diameter. Various fruits of trees and other fragments were 
abundant, usually floating confined in the midst of the small aggregations into which the 
floating timber was almost everywhere gathered. Amongst them were the usual littoral 
seeds, those of two species of Pandanus, and of the Puzzle-seed ( Heritiera littoralis), 
fruits of a Barvingtonia and of Ipomcea pes-caprce. But besides these fruits of littoral 
plants, there were seeds of forty or fifty species of more inland plants. Very small seeds 
were as abundant as large ones, the surface scum being so full of them that they could 
be scooped up in quantities with a fine net. For a report on the nature of these fruits 
and seeds see the Report on the Botany. 1 With the seeds occurred one or two flowers, 
or parts of them. Leaves were absent except those of the palm, on the midribs of 
which some of the pinnae were still present. The leaves evidently drop first to the 
bottom, whilst vegetable drift is floating from a shore ; thus, as the debris sinks in the 
sea water a deposit abounding in leaves, but with few fruits and little or no wood, will be 
formed near shore, whilst the wood and fruits will sink to the bottom farther off the land. 
Much of the wood was floating suspended vertically in the water, and most curiously, 
logs and short branch pieces thus floating, often occurred in separate groups, apart from 
the horizontally floating timber. The sunken ends of the wood were not weighted by 
any attached masses of soil or other load of any kind ; possibly the water penetrates 
certain kinds of wood more easily in one direction with regard to its growth than the 
other, hence one end becomes water-logged before the other. 
It is evident that a wide area of the sea off the mouth of the Mamberan River is thus 
constantly covered with drift wood, for the floating wood is inhabited by various animals, 
which seem to belong to it as it were. The fruits and wood were covered with the eggs 
of a Gasteropod Mollusc, and with a Hydroid, and the interstices were filled with 
Radiolarians washed into them and gathered in masses, just as Diatoms, in the Antarctic 
Ocean, are gathered together in the honeycombed ice. Two species of crabs inhabit the 
logs in abundance, and a small Dendroeoele Planarian swarms all over the drift matter 
and on the living crabs also. A Lepas was common on the logs. Enormous quantities 
of small fish swarmed under the drift wood, and troops of Dolphins ( Coryphcena ) and 
small Sharks ( Carcharias ), 3 or 4 feet long, were seen feeding on them, dashing in 
amongst the logs, splashing the water, and showing above the surface, as they darted on 
their prey. The wood which had been longest in the water was bored by a Pholas. 
A large flock of the very widely spread Phalarope ( Plicdaropus hyperboreus ) was 
seen flying over the drift wood, no doubt following the timber out from shore, and roost- 
ing on it. In England this bird is considered as one of the visitors from the far north, 
so that it seems strange to meet with it at New Guinea, although it was previously known 
from the Arrou Islands. Some specimens shot had small surface Crustacea in their 
stomachs. The various smaller animals no doubt congregate about the drift wood because 
V* 
1 Bot. Chall. Exp., part iii., 1885. 
