e coral is secreted by the
animal, it will form a wall round them; but if, by any accident, the
parasite animal should not keep a passage from the coral to the surface
of the body of the animal clear, which it must be constantly induced to
do, since by this means it procures food, the coral animal will in a
very short time close over it and bury it alive in the mass of the
coral; and this, from the number of these animals, of all sizes and in
different stages of growth, which are to be found in the substance of
the large and massive corals, must often be occurring. Thus the Italian
romance is often literally fulfilled in nature."

Certain birds are parasitic, in this sense, that they compel or induce
other birds to perform the labour of incubation and of rearing their
young. The Rhea or Ostrich of South America is parasitical on its own
species; the females laying each several eggs in the nests of several
other females, and the male ostrich taking all the cares of incubation.
More familiar examples, however, occur in our own Cuckoo, and in the
Cowpen birds (_Molothrus_ _pecoris_ and _M. niger_) of North and South
America. "These fasten themselves," as has been remarked by Mr Swainson,
"on another living animal, whose animal heat brings their young into
life, whose food they live upon, and whose death would cause theirs
during the period of infancy."

The habit, at least in the case of the European Cuckoo, is so well
known, that I need not do more than merely allude to the fact, that the
female seeks for the nests of other insect-eating birds, always much
smaller than itself, and deposits its own eggs,--a single egg in each;
that this stranger egg is hatched by the foster-mother with all care,
and the young bird is nurtured with all tenderness even at the expense
of its own proper eggs and young, which in general are sacrificed in the
course of the process. Every schoolboy knows these facts, but few
perhaps have ever suspected the existence of a romantic feeling of love
and fealty in the little bird towards the cuckoo herself, prompting the
rendering of the service required as a coveted honour. Yet a naturalist
has communicated to Mr Yarrell some facts which certainly look this way;
and because they are indubitably the very romance of natural history, I
cite them, leaving my readers to judge of their value.

"As you have contributed," writes Mr W. C. Newby of Stockton, "so much
to the information and amusement of the n