30 
MICROLEPIDOPTERA OF NEW GUINEA 
be that the transference was not effected by any nearly complete land 
connection, but. took place across a wide channel of several hundred miles, 
and that only a few accidentally selected forms made their way across, at a 
period which can hardly be later than the Cretaceous; from this very 
limited and casual immigration the peculiar and specialised Australian 
stock was developed”. 
Meyrtck has difficulties with the explanation of this distribution on 
account of the fact that he regards the Eucosminae as ancestral to the 
Tortricinae. Heinrich expresses a view opposite to that of Meyrick and 
regards the Tortricinae as the oldest of the two. II we accept his view, 
it is evident that the problem of the above mentioned distribution loses 
most of its snags. 
Granted that the Indian region is the cradle of the Tortricoid Lepi- 
doptera, the logical conclusion is that the invasion of these insects in 
Australia has taken place at the period in which the Eucosminae were in 
an early stage of development out of the Tortricinae, and Mere far less in 
number. Consequently they had less chance in following the latter on their 
invasion of Australia. In that continent the Tortricinae came to an extre- 
mely rich development along new lines, favoured by the new, optimal 
conditions, and also by absence of the Eucosminae which elsewhere must 
be potential rivals as they have identical life-habits. 
Meyrick’s conception cited above does not concern the Papuan fauna 
because at the time of his publication little was known about it . It is of 
interest that the conditions in New Guinea appear to be exactly the same 
as in Australia and New Zealand, viz., the Tortricinae predominate, 
outnumbering the Eucosminae in exactly the same proportion as in those 
countries. About 159 species of Tortricinae have been collected by the 
Expedition, as against 56 species of Eucosminae. 
Thus the fauna of New Guinea in this respect may ha\ e the same 
“character” as that of Australia. On the other hand the New Guinean 
Tortricinae are decidedly not of “Australian” aspect but they are typical 
for the Papuan region as such. It is sufficient to think' of the remarkable 
and conspicuous diurnal species of the endemic CMonothremma (tribe 
Zacoriscini), to understand this. We hope to return to this matter 
later. 
Provisional key to the Papuan genera of the Tortricinae 1 ) 
1. Females with corethrogyne (fig. 24) 2 
Females without corethrogyne ® 
2. Head smooth, corethrogyne large, ventro-lateral 2 ) . Zacorisca Meyrick 
Head with appressed or rather roughish scales 2 
3. Corethrogyne small, ventral, eighth tergite swollen, forming a vesicle 
q A definitive key will be given in the next part of this paper. 
q This feature can easily be observed in dried specimens with a magnification 
of 10 — 30 times. 
