Bulletin - United States National Museum

MICROLEPIDOPTERA OF PHILIPPINE ISLANDS 3
should, therefore, be made with utmost caution; however, this applies
to the absence of certain elements. The presence of other elements,
of com"se, renders absolute and, therefore, important zoogeographic
information.
The available material of Alicrolepidoptera, however scanty, has a
pronovmced Malayan character, with distinctly marked elements
from Borneo, Celebes, and, also, Java. Unfortunately, the faunas
of the former two islands are comparatively little knoAMi.
The Papuan element is not nmnerous, but imdoubtedly present.
Perhaps the most marked and important in this respect is the characteristic
genus Peridaedala Meyi'ick (Olethreutinae), -uith three species
in New Guinea and not less than six m the Phihppmes; two records
of the genus from the Great Simda Islands have recently become
available.
Little can be said as yet of the microlepidopterous elements of the
early northern invasion in Luzon. Of the thi-ee species which occur
in both Formosa and the Pliilippines, one indeed is from Luzon, but
the second is from Panay and the third from Mindanao.
The most characteristic featiu-e of the fauna without doubt is its
high percentage of endemisms, especially of the species. Of the total
of 291 species, 203 are endemic, 88 apodemic. Of the 138 genera,
however, only 18 are endemic, 120 apodemic. These endemisms
are not always striking, although some marked exceptions occur.
Most characteristic are numerous \4carious species, differing from
their allies in neighboring regions by minor external structiu-e and
by genitalia. Some of these forms have escaped the attention of
former authors and were erroneously identified M-ith their closest
relatives from other regions.
This interesting feature shows the considerable independence of
the Philippine faima and that the isolation of the region must have
been of sufficient duration to create the nmnerous \dcarious species,
but that it was not long enough for the development of so many
genera.
Although the Philippine Islands represent a region that is smaller
than the neighboring "Simda Land" (the Sunda shelf) or the Papuan
region, its flora, faima, and geology are certainly not less complex.
One is,
therefore, entitled to expect the existence of as rich a fauna of
Microlepidoptera as in the other two regions; the more so because
of the great variety of plant pro\'inces in the Philippines, the diversity
of altitude of the habitats and the existence of extensive forests,
especially the lowland dipterocarpous forest.
It was, therefore, a reciu"rent disappointment to discover how
limited is om* knowledge of the Philippine Microlepidoptera. When
studying the faunas of the Malay Archipelago and the Papuan region