rees, but prey there upon nocturnal Saurians, geckoes, small birds and
their young; and they are perfectly harmless, although they often try to
bite. It is strange that none of the numerous specimens which it has
been attempted to bring to Europe have ever fed in captivity; whilst in
South America they take their food freely in confinement, provided that
some green plants are placed in their cage.

In Ceylon I have never seen any specimen of a larger size than three
feet; whilst they are known to attain to more than five on the Indian
Continent.

The inference is obvious, that the green coloration of the majority of
tree-snakes has more or less connection with their habits and mode of
life. Indeed, whenever a green-coloured snake is observed, it may at
once be pronounced, if slender or provided with a prehensile tail, to be
of the kind which passes its life on trees; but if it be short-bodied
then it lives on the prairies. There are nevertheless tree-snakes which
have a very different coloration; and one of the most remarkable species
is the _Passerita fusca_ or _Dryinus fuscus_, of which a figure is
annexed. It closely resembles the green Passerita in form, so that
naturalists have considered it to be a mere variety. It is entirely of a
shining brown, shot with purple, and the yellow longitudinal stripe
which runs along the side of the belly of the green species, is absent
in this one. It is much more rare than the green one, and does not
appear to be found in Hindostan: no intermediate forms have been
observed in Ceylon.

_Water-Snakes._--The fresh-water snakes, of which several species[1]
inhabit the still waters and pools, are all harmless in Ceylon. A
gentleman, who found near a river an agglutinated cluster of the eggs of
one variety (_Tropidophis schistosus_), placed them under a glass shade
on his drawing-room table, where one by one the young reptiles emerged
from the shell to the number of twenty.

[Footnote 1: Chersydrus granulatus, _Merr_.; Cerberus cinereus. _Daud._;
Tropidophis schistosus, _Daud._]

The _sea-snakes_ of the Indian tropics did not escape the notice of the
early Greek mariners who navigated those seas; and amongst the facts
collected by them, AElian has briefly recorded that the Indian Ocean
produces serpents _with flattened tails_[1], whose bite, he adds, is to
be dreaded less for its venom than the laceration of its teeth. The
first statement is accurate, but the latter is incorrect, a