icularly in Mexico, where these subterranean passages are
numerous. Near Chiquihuita, about five leagues from the road which leads
to Vera Cruz and Cordova, a large river vanishes into a cave, which is
more than three miles in length."

"Oh, how I should like to see such a large grotto!"

"Your wish shall be gratified, provided we do not lose our way in the
_Terre-Chaude_."

Sumichrast had only a few minutes left us, when we heard a report, and
he reappeared carrying a magnificent bird, whose red plumage had a
purple metallic lustre.

"We have never met with this fine fellow before," said Lucien.

"It is the most brilliant of all the American passerines," I
replied--"the _Ampelis pompadora_; but its splendid attire lasts only
for a very short time. In a few days its bright-colored feathers fall
off, and are replaced by a sombre, dull-looking coat. This moulting,
which is common to many birds, has more than once led ornithologists
into error, who have described, as a new species, a bird which a new
dress has prevented them from recognizing."

[Illustration: "The water . . . disappeared under a low arch."]

The neighborhood of the _sumidero_ furnished us with a dozen birds of
different species; among others, several tanagers peculiar to America,
and a pair of pretty light-brown cuckoos, with fan-shaped tails, which
are merely birds of passage in this locality.

"When you are speaking of a bird, why do you often say it belongs to
Brazil, Guiana, or Peru, when you actually find it in Mexico?" asked
Lucien.

"Because, at certain seasons of the year, many kinds of birds migrate,"
answered my friend; "and they are often found at an immense distance
from the country where they breed. This beautiful blackbird, for
instance, is never seen in Mexico except in the spring, which has caused
it to be called here the _primavera_."

"Look, papa, at these beautiful yellow flowers; they cover the trunk of
this tree so completely that it appears as if they grew on it."

"They are the flowers of the _trop[oe]olum_, or wild nasturtium. This
plant has been cultivated in Europe, where its seed is eaten preserved
in vinegar, and its flowers are used to season salads."

"Then the Mexicans do not know its value, for I have never seen it on
their tables."

"You are right; but still I should have thought that the piquant taste
of the flowers of the _trop[oe]olum_ would have just suited them.
Perhaps they find it too insipid after ha