192 THE MALAYAN PAPILIONIDE AS 
are either almost or entirely restricted to one portion 
of the archipelago :— 
Indo-Malayan Region. Austro-Malayan Region. 
Nox-group. Priamus-group. 
Coon-group. Ulysses-group. 
Macareus-group (nearly). Erechtheus-group. 
Paradoxa-group. 
Dissimilis-group (nearly). 
Brookeanus-group. 
LEPTOCIRCUS (genus), 
The remaining groups, which range. over the whole 
archipelago, are, in many cases, insects of very power- 
ful flight, or they frequent open places and the sea- 
beach, and are thus more likely to get blown from 
island to island. The fact that three such character- 
istic groups as those of Priamus, Ulysses, and Erech- 
theus are strictly limited to the Australian region of 
the archipelago, while five other groups are with equal 
strictness confined to the Indian region, is a strong 
corroboration of that division which has been founded 
almost entirely on the distribution of Mammalia and 
Birds. 
If the various Malayan islands have undergone 
recent changes of level, and if any of them have been 
more closely united within the period of existing 
species than they are now, we may expect to find 
indications of such changes in community of species 
between islands now widely separated; while those 
islands which have long remained isolated would have 
had time to acquire peculiar forms by a slow and 
natural process of modification. 
