10 
Psyche 
[March 
as well as many more-widely distributed genera. Up to a point, there- 
fore, the Carabidae agree with the forest trees, mammals, and birds 
in showing a considerable number of species and genera common to 
the rain forests of New Guinea and tropical Australia. 
When I was collecting on the Atherton Tableland in northeastern 
Australia in 1932, I found not only many Carabidae of obviously New 
Guinean groups but also, in rain forest, many species of Australian 
groups not known to occur in New Guinea. Included were striking 
endemic species of Notonomus , Trichosternus, Leiradira , Pamborus, 
and Mystropomus. Knowing, as I did, that the rain forests of 
Australia and New Guinea had much in common, and knowing that 
the Carabidae of New Guinea were poorly collected, I imagined in 
New Guinea a rich fauna of the genera just named, perhaps in rain 
forest at middle altitudes, but wholly unknown. It was a sort of El 
Dorado for the future, to a young and enthusiastic carabid student. 
But now that I have collected in New Guinea and seen thousands of 
Carabidae collected there by other persons, I know that this El Dorado 
does not exist, and I know why. All the Carabidae common to the 
New Guinean and Australian rain forests are winged and probably 
fly. All the genera mentioned above as represented in rain forest on 
the Atherton Tableland are wholly flightless, and I know now that 
there is no direct relationship between any flightless Carabidae of the 
New Guinean and Australian rain forests. 3 
The difference between the flightless Carabidae of Australia and 
New Guinea goes far beyond mere differences of species and genera. 
The composition and origins of the two faunas are fundamentally 
different. Flightless Carabidae are numerous everywhere in Australia, 
even at low altitudes in the tropical part of the continent including 
Cape York. Many of the species belong to wholly flightless genera or 
even flightless tribes that have evidently been in Australia a long time. 
Derivatives of old Australian flightless groups dominate the flightless 
ground-living carabid fauna of tropical rain forest in Australia. In 
New Guinea, in contrast, no primarily flightless groups of Carabidae 
occur at low altitudes. A very few species of the primarily winged 
3 If tiger beetles are considered Carabidae, Tricondyla aptera 01. is an 
exception to this rule. The genus Tricondyla is primarily Oriental and is 
wholly flightless. Nevertheless T. aptera has reached New Guinea, probably 
rather recently (it is only slightly differentiated there), and has got beyond 
New Guinea to the mid-peninsular rain forests of Cape York. (It has reached 
the Solomon Islands and New Hebrides too.) It is a good sized (nearly an 
inch long), big-eyed, ant-like, active insect, which lives on tree trunks in rain 
forest. It has probably dispersed on floating trees, which ground-living 
Carabidae are not likely to do. 
