THE AUSTRALIAN NATURALIST 103 
chiefly found in South-Hastern Australia, there is no di- 
viding line, and the species mingle in the Central East 
Coast, and even predominate in the higher portions of the 
Main Divide and Queensland. Already a slight division 
into an Eastern and a Western region is to be found, and 
these divergences will increase as time goes on. The char- 
acteristic groups of butterflies inhabiting this Southern 
and South-Eastern region are Heteronympha, Xenica and 
the skippers. 
The second great group is that which has reached us 
from the north, and about this we can speak with more 
certainty, as it has appeared within comparatively recent 
geological times. This second group is the Papuan ele- 
ment in our fauna, having had its origin some- 
where near the great island lying to the north of Aus- 
tralia. There appears to have been at least three migra- 
tions of butterfiies from the centre of dispersion of these 
Papuan forms, and along the radii of these dispersions we 
have to take into consideration climate, distance, and time, ° 
as well as natural barriers. To the older of these migra- 
tions belong the several Papuan butterflies we see about 
Sydney, the large black-and-white orange’ feeder Papilio 
aegeus, and the black and blue camphor laurel feeder 
Papilio sarpedon choredon, and many others; the remain- 
ing migrations into Australia from New Guinea have not 
reached so far south along the Hast Coast as Sydney, 
and so do not particularly concern us. Sufficient to say 
that these species that are limited in their ranges east 
and west of New Guinea do not extend so far south in 
Australia. The third group of butterflies is the element 
in North-West Australia, received from the Malayan 
Archipelago, by way of Timor. This group) is not a very 
large one, being only represented by a few species near 
Darwin, and has very little influence~on the butterfly 
fauna of the rest of Australia. 
PRIZE ESSAY. 
Members are requested to note that Mr. E. J. Bick- 
ford has offered a prize of £1°1/- for the best essay on 
““The Orchids of New South Wales.”’ 
