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 coinstantaneous as in a regiment of
soldiers; but this cannot happen from anything like voluntary
action with the ovules, or the confervae, nor is it probable among
the infusoria. Secondly, what causes the length and narrowness of
the bands? The appearance so much resembles that which may be seen
in every torrent, where the stream uncoils into long streaks the
froth collected in the eddies, that I must attribute the effect to
a similar action either of the currents of the air or sea. Under
this supposition we must believe that the various organised bodies
are produced in certain favourable places, and are thence removed
by the set of either wind or water. I confess, however, there is a
very great difficulty in imagining any one spot to be the
birthplace of the millions of millions of animalcula and confervae:
for whence come the germs at such points?--the parent bodies having
been distributed by the winds and waves over the immense ocean. But
on no other hypothesis can I understand their linear grouping. I
may add that Scoresby remarks that green water abounding with
pelagic animals is invariably found in a certain part of the Arctic
Sea.

(PLATE 7. CATAMARAN (BAHIA).)

CHAPTER II.

(PLATE 8. BOTOFOGO BAY, RIO DE JANEIRO.)

Rio de Janeiro.
Excursion north of Cape Frio.
Great Evaporation.
Slavery.
Botofogo Bay.
Terrestrial Planariae.
Clouds on the Corcovado.
Heavy Rain.
Musical Frogs.
Phosphorescent Insects.
Elater, springing powers of.
Blue Haze.
Noise made by a Butterfly.
Entomology.
Ants.
Wasp killing a Spider.
Parasitical Spider.
Artifices of an Epeira.
Gregarious Spider.
Spider with an unsymmetrical Web.

RIO DE JANEIRO.

APRIL 4 TO JULY 5, 1832.

A few days after our arrival I became acquainted with an Englishman
who was going to visit his estate, situated rather more than a
hundred miles from the capital, to the northward of Cape Frio. I
gladly accepted his kind offer of allowing me to accompany him.

APRIL 8, 1832.

Our party amounted to seven. The first stage was very interesting.
The day was powerfully hot, and as we passed through the woods,
everything was motionless, excepting the large and brilliant
butterflies, which lazily fluttered about. The view seen when
crossing the hills be