1877.] Natural History of Fanning’s Group. 67 
Washington Island, the most remarkable of the group, pre- 
sents several very interesting geological features. The evidences 
of the operation of some great disturbing agent are more plainly 
visible here than elsewhere. Either this force must have been 
extremely local in its operation, or else it was exerted upon the 
member of the group which we have just considered when it was 
in such a condition as not to show it. The latter hypothesis is 
the most reasonable. Washington Island is an obliterated atoll. 
In the place of the usual salt water lagoon there is a lake of fresh 
water, one mile long and half a mile wide, with a depth of four 
fathoms in its deepest part. No shore platform makes out from 
the land at low water, but the sea at all stages of the tide breaks 
directly on the beach, except at the angles of the island where 
reefs extend a certain distance into the sea. The beach shelves 
rather abruptly to the water’s edge. The highest: part of the 
land is about fifteen feet high, and over all the interior of the 
island there are outcroppings of the reef-rock and the rock of 
beach formation. All traces of the former passage from the sea 
into the lagoon have been obliterated. The salt water of the 
lagoon has either drained off through the light, porous soil, or 
has been freshened by the immense rain-falls which occur in 
these latitudes. The latter event is not improbable, consider- 
ing the situation of the island on the edge of the trades, in the 
region of variable winds, where rains are frequent and heavy. 
In time past, the rim of land inclosed three lagoons. One, the 
largest, is now the lake ; the others are about half the size of the 
first, and are converted into peat-bogs. The latter are thickly 
overgrown with rushes and contain a solid deposit of vegetable 
matter three or four feet deep, composed of the roots, trunks, 
and débris of the cocoanut and pandanus trees closely matted by 
the roots of the rushes. The time of our visit was just after a 
heavy rain, and a layer of water from six to eighteen inches deep 
covered the surface of the bogs. 
_ The island supports a dense and luxuriant growth of vegeta- 
tion, and a greater number of species are represented there than 
on any of the other islands of the group. 
The water of the lake is just perceptibly brackish ; and the 
only life it is said to contain are a species of eel and a shrimp, 
both of which we were told are different from anything found in 
the water surrounding the island. This information was derived 
from an intelligent Englishman, who had visited the island sev- 
eral times to superintend the gathering of the cocoanuts. They 
