Phalaenae, Moths. 
The enormous assemblage formed by the Indo-Australian Phalaenae is by no means so sharply sepa¬ 
rated from the butterflies of that fauna as in the Palearctic Region. The peculiar Australian species Euschemon 
rafflesiae , which forms the conclusion of the butterflies dealt with in vol. IX, constitutes a connecting-link and 
has recently often been referred to the Ileterocera , as it differs strikingly in several respects both from the 
Ehopalocera and the Grypocera. We prefer, however, in this work to leave it in the position which it occupies 
in Kirby’s very widely known Catalogue, contenting ourselves with pointing out its taxonomic uncertainty. 
Owing to the early colonization of India our knowledge of the Indo-Australian moths already made 
considerable progress even during the first years in which any interest has been taken in exotic insects. The 
East India Company early began to admit larvae also into their museum and so the foundations of a thorough 
knowledge of the life-history were early laid, though far later than Merian made known the first moth larvae 
from tropical America. Moreover the vigorous colonization of the Dutch Indies early made us acquainted 
with the striking forms of the Malay Archipelago, although many a surprise may still be in store for us 
owing to the character of the Indo-Australian archipelagos as a maze of islands, some of which are even 
to-day difficult of access. 
On the whole Anterior India may be considered well known as regards its Ileterocera . In Further 
India scarcely more than the coasts and several points of the Strait have yet been well explored, whilst in 
the interior of Siam, Annam and Tonkin many novelties will probably still lie found. Burma and Tenasserim, 
adjoining Anterior India, have been well worked, on the other hand in large districts of south-western China 
pioneers have only just been occupied with the first rough work. As regards the Indo-Australian part of 
Japan, especially Formosa, the Japanese have recently been so actively engaged in investigating it that it 
will not be long before an approximate idea of its Heterocerous fauna can be formed. Australia, well known 
in the south and east, has still huge tracts of land which are scarcely touched, and with regard to this part 
of the world the treatment of the Heterocera in our work must be regarded as only provisional; at the same 
time even the first small genus, Synemon, yields over half a dozen new forms, although, as not coming within 
the scope of a work of reference, our contributors have by no means been in search of novelties. The South 
Sea also, poor as it is in species in most parts, will still bring something new to light; only New Zealand, 
which has more than once been thoroughly worked out monographically, even to the smallest forms, can be 
regarded as well known. 
It is evidently no more possible than with the Palearctic fauna, to say much about the Indo-Australian 
Heterocera in general. On the whole we meet with an extraordinarily large number of recent groups; in the 
Malay Archipelago in particular they are very strongly developed. Proceeding from thence towards the north¬ 
west we see the Heterocera approaching the European forms; to the north-east we find pretty generally, as 
in the east of the Palearctic Region, that large forms predominate; to the east the fauna becomes more meagre 
as the islands become fewer and more isolated and to the south it enters Australia, where it mixes with an 
endemic fauna consisting of very archaic forms of a distinctive character. It is not possible to separate these 
two elements of which the Australian Heterocera are composed, as they have become completely blended. 
Wallace, who recognized the residue of the aborginal Australian fauna as altogether distinct and moreover 
did not found his geographical system on the insects alone, on this account separated Australia as one of 
his main faunistic regions. In this he was followed by Pagenstecher, who likewise opposed the amalgamation 
of India with Australia into one fauna. Most other authors, and also the practical entomologists (collectors 
and dealers), have accepted the arrangement which we follow here, uniting Australia with the Indian fauna. 
This has not been done because the still easily recognizable indigenous forms (notably among the Heterocera 
Synemon, also Colussa, Pielus, Trichetra. Epicoma etc. etc.) have been overlooked or their peculiarities not 
sufficiently appreciated, but because proceeding from the north the Indian immigrants have completely sub¬ 
merged the primitive fauna and as the forms derived from these immigrants have spread right to the south 
