by the
same cause. Peron, the distinguished naturalist, in the "Voyage aux
Terres Australes," gives no less than twelve references to voyagers
who have alluded to the discoloured waters of the sea (volume 2
page 239). To the references given by Peron may be added,
Humboldt's "Personal Narrative" volume 6 page 804; Flinder's
"Voyage" volume 1 page 92; Labillardiere, volume 1 page 287;
Ulloa's "Voyage"; "Voyage of the Astrolabe and of the Coquille";
Captain King's "Survey of Australia" etc.)

In the sea around Tierra del Fuego, and at no great distance from
the land, I have seen narrow lines of water of a bright red colour,
from the number of crustacea, which somewhat resemble in form large
prawns. The sealers call them whale-food. Whether whales feed on
them I do not know; but terns, cormorants, and immense herds of
great unwieldy seals derive, on some parts of the coast, their
chief sustenance from these swimming crabs. Seamen invariably
attribute the discoloration of the water to spawn; but I found this
to be the case only on one occasion. At the distance of several
leagues from the Archipelago of the Galapagos, the ship sailed
through three strips of a dark yellowish, or mud-like water; these
strips were some miles long, but only a few yards wide, and they
were separated from the surrounding water by a sinuous yet distinct
margin. The colour was caused by little gelatinous balls, about the
fifth of an inch in diameter, in which numerous minute spherical
ovules were embedded: they were of two distinct kinds, one being of
a reddish colour and of a different shape from the other. I cannot
form a conjecture as to what two kinds of animals these belonged.
Captain Colnett remarks that this appearance is very common among
the Galapagos Islands, and that the direction of the bands
indicates that of the currents; in the described case, however, the
line was caused by the wind. The only other appearance which I have
to notice, is a thin oily coat on the water which displays
iridescent colours. I saw a considerable tract of the ocean thus
covered on the coast of Brazil; the seamen attributed it to the
putrefying carcass of some whale, which probably was floating at no
great distance. I do not here mention the minute gelatinous
particles, hereafter to be referred to, which are frequently
dispersed throughout the water, for they are not sufficiently
abundant to create any change of colour.

There are two circumstances in the