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 imbedded: 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 directions of the bands indicate 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 carcase 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 above accounts which
appear remarkable: first, how do the various bodies which
form the bands with defined edges keep together? In the
case of the prawn-like crabs, their movements were as
co-instantaneous as in a regiment of soldiers; but this cannot