THE COMPLETED ATOLL. 325 
Kotzebue observes, that “in the inner part of Otdia (one 
of the Marshall Islands) there is a lake of sweet water; and 
in Tabual, of the Group Aur, a marshy ground exists. There 
is no want of fresh water in the larger islands; it rises in 
abundance in the pits dug for the purpose.” (Voyage, London, 
1821, i. 145.) 
The only source of this water is the rain, which, perco- 
lating through the loose sands, settles upon the hardened 
coral rock that forms the basis of the island. As the soil is 
white or nearly so, it receives heat but slowly, and there is 
consequently but little evaporation of the water that is once 
absorbed. 
Water is sometimes obtained by making a large cavity in 
the body of a cocoanut tree, two feet or so from the ground. 
At the Duke of York’s Island, and probably also at the adja- 
cent Bowditch Island, this method is put in practice; the 
cavities hold five or six gallons of water. 
The extensive reefs about coral islands, as already stated, 
abound in fish, which are easily captured, and the natives, 
with wooden hooks, often bring in larger kinds from the 
deep waters. From such resources a population of seven 
thousand persons is supported on the single island of Tapu- 
teuea, whose whole habitable area does not exceed six square 
miles, 
There are also shell-fish of edible kinds, and others that 
are the source of considerable activity in pearl-fishing. 
Although the vegetation of coral islands has the luxuri- 
ance that characterizes more favored tropical lands, the num- 
ber of species of land plants is small. A work on the 
“Botany of the Paumotus” would contain descriptions of 
only twenty-eight or thirty species. The most common kinds 
are the following : — 
