time most useful to man. Who
can doubt that these qualities are united in the banana, the
cocoa-nut, the many kinds of palm, the orange, and the bread-fruit
tree?

During this day I was particularly struck with a remark of
Humboldt's, who often alludes to "the thin vapour which, without
changing the transparency of the air, renders its tints more
harmonious, and softens its effects." This is an appearance which I
have never observed in the temperate zones. The atmosphere, seen
through a short space of half or three-quarters of a mile, was
perfectly lucid, but at a greater distance all colours were blended
into a most beautiful haze, of a pale French grey, mingled with a
little blue. The condition of the atmosphere between the morning
and about noon, when the effect was most evident, had undergone
little change, excepting in its dryness. In the interval, the
difference between the dew point and temperature had increased from
7.5 to 17 degrees.

On another occasion I started early and walked to the Gavia, or
topsail mountain. The air was delightfully cool and fragrant; and
the drops of dew still glittered on the leaves of the large
liliaceous plants, which shaded the streamlets of clear water.
Sitting down on a block of granite, it was delightful to watch the
various insects and birds as they flew past. The humming-bird seems
particularly fond of such shady retired spots. Whenever I saw these
little creatures buzzing round a flower, with their wings vibrating
so rapidly as to be scarcely visible, I was reminded of the sphinx
moths: their movements and habits are indeed in many respects very
similar.

(PLATE 13. RIO DE JANEIRO.)

Following a pathway I entered a noble forest, and from a height of
five or six hundred feet, one of those splendid views was
presented, which are so common on every side of Rio. At this
elevation the landscape attains its most brilliant tint; and every
form, every shade, so completely surpasses in magnificence all that
the European has ever beheld in his own country, that he knows not
how to express his feelings. The general effect frequently recalled
to my mind the gayest scenery of the Opera-house or the great
theatres. I never returned from these excursions empty-handed. This
day I found a specimen of a curious fungus, called Hymenophallus.
Most people know the English Phallus, which in autumn taints the
air with its odious smell: this, however, as the entomologist is
aware, is to some