The climate, during the months of May and June, or the beginning of
winter, was delightful. The mean temperature, from observations taken
at nine o'clock, both morning and evening, was only 72 degs. It often
rained heavily, but the drying southerly winds soon again rendered the
walks pleasant. One morning, in the course of six hours, 1.6 inches of
rain fell. As this storm passed over the forests which surround the
Corcovado, the sound produced by the drops pattering on the countless
multitude of leaves was very remarkable, it could be heard at the
distance of a quarter of a mile, and was like the rushing of a great
body of water. After the hotter days, it was delicious to sit quietly
in the garden and watch the evening pass into night. Nature, in these
climes, chooses her vocalists from more humble performers than in
Europe. A small frog, of the genus Hyla, sits on a blade of grass
about an inch above the surface of the water, and sends forth a
pleasing chirp: when several are together they sing in harmony on
different notes. I had some difficulty in catching a specimen of this
frog. The genus Hyla has its toes terminated by small suckers; and I
found this animal could crawl up a pane of glass, when placed
absolutely perpendicular. Various cicidae and crickets, at the same
time, keep up a ceaseless shrill cry, but which, softened by the
distance, is not unpleasant. Every evening after dark this great
concert commenced; and often have I sat listening to it, until my
attention has been drawn away by some curious passing insect.
At these times the fireflies are seen flitting about from hedge to
hedge. On a dark night the light can be seen at about two hundred
paces distant. It is remarkable that in all the different kinds of
glowworms, shining elaters, and various marine animals (such as the
crustacea, medusae, nereidae, a coralline of the genus Clytia, and
Pyrosma), which I have observed, the light has been of a well-marked
green colour. All the fireflies, which I caught here, belonged to the
Lampyridae (in which family the English glowworm is included), and the
greater number of specimens were of Lampyris occidentalis. [4] I found
that this insect emitted the most brilliant flashes when irritated: in
the intervals, the abdominal rings were obscured. The flash was almost
co-instantaneous in the two rings, but it was just perceptible first in
the anterior one. The shining matter was fluid and very adhesive:
little spots, where the skin had been torn, continued bright with a
slight scintillation, whilst the uninjured parts were obscured. When
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