e 
INTRODUCTION. By Dr. A. Seitz. 
of the American in number of species, in number of individuals they remain far behind their represen¬ 
tatives in the New World, where certain species, e. g. Oiketicus platensis, have become regular enemies to 
horticulture. 
The Lasiocampids, on the whole of pretty similar distribution over all non-polar lands, show 
remarkable peculiarities in many districts of the Indo-Australian Region. In the first place, certain sections 
of this family form a part of that typical Australian primitive fauna which, confined to the south of the 
continent, has there produced forms to which we find no parallel elsewhere. Everyone who has collected 
in Australia will remember the gigantic Zebra larvae, which produce Chalepteryx collesi, formerly included 
among the Saturniids; also the sharp-snouted Opsirhina and others. As in the Palaearctic Region the pine 
moth, iJendrolimus pint, sometimes increases to such an extent as to become a menace to the forests, so 
also in India we meet with many Lasiocampids among the commonest moths; thus in India and South 
(dhina 1'rabala vishnit, whose bright-coloured larvae with pencil-bearing striped heads may be found on 
almost every bush and all the year round. Suana concolor is distinguished by powerfully developed 
females, which stand in much the same proportion to their only medium-sized males as the Liparid 
(tcneria dispar. 
The Saturniids attain in the Indian Attacus atlas the largest wing area known in the Lepidoptera, 
although they are surpassed in expanse by some Papilio females ami by the American Noctuicl Thysania 
agrippina. On the whole the Indo-Australian Region has not so many Saturniids as America, but it pos¬ 
sesses some very singular forms in the long-tailed Coscinoeera. 
The Bombycidae and Eupterotidae are families with very few forms, which come between the 
Saturniids and Lasiocampids. The former must be specially mentioned on account of the silkworm, Bombyx 
mori, an insect of enormous commercial and economic importance. As we have already noticed in the 
general introduction (vol. I), it may now be accepted with certainty that the silkworm comes originally 
from China, but whether from the Palaearctic North or the Indo-Australian South cannot now be determined 
on account of its general naturalisation and importation. 
The Sphingids are represented in the Indo-Australian Region by very many species, but their 
larvae show less tendency towards those grotesque forms such as America possesses in the zebra-like 
Pseudosphinx and in the log-like Philanipehts anehcmolus and Parhylia larvae, under the weight of which 
large branches on the bushes are bent down to the ground. The largest Indo-Australian Sphingids have 
simple green time ri nth its larvae; they are Langia zenzeroidcs (which also encroaches on the Palaearctic 
Region), the expanse of which insect is 17 cm and whose larva might be taken for an enormous Amorpha 
popidi larva whose lateral stripes, are lost, as well as the still larger Oocquosa and Met ami mas, which belong 
to the old Southern Australian fauna. Their larvae, though green in colour and with the well-known 
oblique lateral streaks, are in form perhaps the most singular of all known Sphingid larvae. Whilst the 
horn on the tail is wanting, the head is produced into a long, somewhat curved point, so that it forms a 
true continuation of the anteriorly much diminished body. If we imagine the larva in its resting posture, 
namely very much erected, it forms a single long green horn. — Besides this the Indo-Australian Sphingid 
larvae often resemble snakes’ heads, their two lateral eye-spots, by the extremely vivid glitter of the 
enamel-gloss on them, not only imitating the eye, but also the gleam of the snake; an appearance to 
which I have found no parallel in Palaearctic lands. 
The Notodontids can scarcely be discussed as a whole on account of their heterogeneity, already 
mentioned in the introduction to the American part. It may be particularly mentioned that many 
specifically peculiar forms, such as Centra, are found in the remotest parts of Australia. Many groups of 
which the Palaearctic fauna only possesses small, inconspicuous forms attain in the Indo-Australian fauna 
to a notable size. 
The Noctuids of the Indo-Australian Region bear the same relation to those of the Palaearctic 
lands as those of South America to the North American fauna. In place of Catocala occurs Ophideres, in 
place of Mania and Spintherops the bat-like Patula and Nyctipao. Singular modifications of the hindwing 
of the male are often found in the giant Noctuids of the Indo-Australian Region, and are perhaps 
connected with the peculiar rattling or cracking sounds which the males make in flying, and which 
reminded me forcibly of the rattling of the Neotropical Ageronia. Taken as a whole the Noctuids do not 
form in the Indo-Australian Region such an overwhelmingly large proportion of the Lepidoptera as was 
the case in the Palaearctic Region. 
Finally, the Indo-Australian Geometrids are confined to similar limits in this as in the Palaearctic 
and American Regions. Species of Elphos and Erebomorpha are here, as in the Palaearctic Region, the 
largest Geometers. Their slenderness forms a noteworthy contrast to the heavy, stout-bodied Oenocliroma, 
which are among the more remarkable of the Australian forms. It was erroneously believed for a long 
time that a gigantic Geometer had been found in Nyctalemon, but the larva is 16-legged, and its proper 
place is beside Urania. 
