Travel Reference
In-Depth Information
able old-world forms which are absent from the one are equally so from the other, such as
Pheasants, Grouse, Vultures, and Woodpeckers; while Cockatoos, Broad-tailed Parrots,
Podargi, and the great families of the Honeysuckers and Brush-turkeys, with many others,
comprising no less than twenty-four genera of land-birds, are common to both countries,
and are entirely confined to them.
When we consider the wonderful dissimilarity of the two regions in all those physical
conditions which were once supposed to determine the forms of life—Australia, with its
open plains, stony deserts, dried up rivers, and changeable temperate climate; New Guinea,
with its luxuriant forests, uniformly hot, moist, and evergreen—this great similarity in their
productions is almost astounding, and unmistakeably points to a common origin. The re-
semblance is not nearly so strongly marked in insects, the reason obviously being, that this
class of animals are much more immediately dependent on vegetation and climate than are
the more highly organized birds and Mammalia. Insects also have far more effective means
of distribution, and have spread widely into every district favourable to their development
and increase. The giant Ornithopteræ have thus spread from New Guinea over the whole Ar-
chipelago, and as far as the base of the Himalayas; while the elegant long-horned An-
thribidæ have spread in the opposite direction from Malacca to New Guinea, but owing to
unfavourable conditions have not been able to establish themselves in Australia. That coun-
try, on the other hand, has developed a variety of flower-haunting Chafers and Buprestidæ,
and numbers of large and curious terrestrial Weevils, scarcely any of which are adapted to
the damp gloomy forests of New Guinea, where entirely different forms are to be found.
There are, however, some groups of insects, constituting what appear to be the remains of
the ancient population of the equatorial parts of the Australian region, which are still almost
entirely confined to it. Such are the interesting sub-family of Longicorn coleop-
tera—Tmesisternitæ; one of the best-marked genera of Buprestidæ—Cyphogastra; and the
beautiful Weevils forming the genus Eupholus. Among butterflies we have the genera
Mynes, Hypocista, and Elodina, and the curious eye-spotted Drusilla, of which last a single
species is found in Java, but in no other of the western islands.
The facilities for the distribution of plants are still greater than they are for insects, and it
is the opinion of eminent botanists, that no such clearly-defined regions can be marked out
in botany as in zoology. The causes which tend to diffusion are here most powerful, and
have led to such intermingling of the floras of adjacent regions that none but broad and gen-
eral divisions can now be detected. These remarks have an important bearing on the prob-
lem of dividing the surface of the earth into great regions, distinguished by the radical dif-
ference of their natural productions. Such difference we now know to be the direct result of
