use of
their unwholesomeness he throws little light; and still less on the
extraordinary but undoubted fact that the same species may be
poisonous in one island and harmless in another; and that of two
species so close as to be often considered as the same, one may be
poisonous, the other harmless. The yellow-billed sprat, {102} for
instance, is usually so poisonous that 'death has occurred from
eating it in many cases immediately, and in some recorded instances
even before the fish was swallowed.' Yet a species caught with
this, and only differing from it (if indeed it be distinct) by
having a yellow spot instead of a black one on the gill-cover, is
harmless. Mr. Hill attributes the poisonous quality, in many cases,
to the foul food which the fish get from coral reefs, such as the
Formigas bank, midway between Cuba, Hayti, and Jamaica, where, as
you 'approach it from the east, you find the cheering blandness of
the sea-breeze suddenly changing to the nauseating smell of a fish-
market.' There, as off similar reefs in the Bahamas and round
Anegada, as we'll as at one end of St. Kitts, the fish are said to
be all poisonous. If this theory be correct, the absence of coral
reefs round Trinidad may help to account for the fact stated by Mr.
Joseph, that poisonous fish are unknown in that island. The
statement, however, is somewhat too broadly made; for the Chouf-
chouf, {103a} a prickly fish which blows itself out like a bladder,
and which may be seen hanging in many a sailor's cottage in England,
is as evil-disposed in Trinidad as elsewhere. The very vultures
will not eat it; and while I was in the island a family of Coolies,
in spite of warning, contrived to kill themselves with the nasty
vermin: the only one who had wit enough to refuse it being an idiot
boy.

These islands of the Bocas, three in number, are some two miles long
each, and some eight hundred to one thousand feet in height; at
least, so say the surveyors. To the eye, as is usual in the
Tropics, they look much lower. One is inclined here to estimate
hills at half, or less than half, their actual height; and that from
causes simple enough. Not only does the intense clearness of the
atmosphere make the summits appear much nearer than in England; but
the trees on the summit increase the deception. The mind, from home
association, supposes them to be of the same height as average
English trees on a hill-top--say f