OF THE MALAYAN REGION. 37 
proper. The same parallel holds in North Australia Many New Guinea species of 
birds extend, with very slight variation, to the country about Cape York; but when we 
reach the Moreton Bay district all these have disappeared, and we find only true Austra- 
lian species. So the variable forms of O. Poseidon reach North Australia and Cape York, 
while in the Moreton Bay district we find the comparatively well-marked species O. Rich- 
mondia. Similar causes, whether geographical or climatal, have thus produced an ana- 
logous distribution in these widely separated groups of animals. 
9. ORNITHOPTERA CRŒSUS, Felder. 
O. Cresus, Feld. Wien. Ent. Monats. Dec. 1859. O. Croesus, G. R. Gray, Proc. Zool. Soc. 1859, 
p. 424. 
Hab. Batchian (Moluccas) (Wall.). 
Local form, &.—Male : has the orange colour of the upper surface of a much deeper 
fiery-red hue; on the under surface, the black spots of the lower wings are nearer the 
margin, and the yellow spots below them are entirely absent; there is also a green line 
between the subcostal nervure and the margin; on the under surface of the fore wings 
the green patch in the discoidal cell extends to its base, and is reflexed in a narrow line 
along its upper edge. 
Female: differs still more from that sex in O. Croesus; the white markings on all the 
wings are so large as almost to fill up the spaces between the veins, the lower part of the 
discoidal cell in both upper and under wings being also occupied with a whitish patch; 
the range of spots occupying the posterior margin are of a dusky yellow colour. 
Hab. Ternate (g), Gilolo (9) (Wall.). 
This well-marked local form is no doubt peculiar to Gilolo and the small adjacent 
islands, as the original species is to Batchian. 
I was three months in the island of Batchian before I obtained a specimen of this fine 
insect, which I had seen once or twice only flying high in the air. I at length came 
upon it flying about a beautiful cinchonaceous shrub with white bracts and yellow 
flowers (Mussænda, sp.) ; and having cleared a path round about, I visited the place every 
morning on my way to the forest, and once or twice a week had the satisfaction of cap- 
turing a fine male specimen of O. Cresus. The females were more plentiful and more 
easily caught. I afterwards sent out one of my men with a net every day to look after 
this insect only. He would stay out all day long, wandering up a broad rocky torrent, 
where the males flew up and down occasionally or settled on the rocks which just ap- 
peared above the water. He generally brought me one, and sometimes even two or 
three specimens; and thus, with those that I myself captured at the flowers, I secured 
a fine series of this richly coloured species. 
4. ORNITHOPTERA TITHONUS, De Haan. 
O. Tithonus, De Haan, Verh. Nat. Gesch. Ned. t. 1. f. 1. 
Hab. S.W. Coast of New Guinea (Leyden Museum). 
This remarkable species must be very rare, as I never saw it in any part of the New 
