204 
Psyche 
[October-Decembei 
Fig. 2. Male of Diacamma auslrale x5. 
The workers are very agile and graceful in their movements and 
both Rothney (1889) and Bingham (1903) regard them as by far 
the most intelligent of Oriental ants. 
The species of Diacamma are also of unusual interest from 
the fact that although several of them are common and have 
often been observed in the field, no one has ever been able to 
find in any one of them a form corresponding to the winged, 
fertile female, or queen of other ants. Frederick Smith (1863), 
nearly 60 years ago, described a worker and “female” of D. 
rugosum subsp. tortuolosum and remarked that “the sexes were 
identified by Mr. Wallace”, but there can be little doubt that he 
had before him a female belonging to some very different Ponerine 
genus, possibly Bothroponera. In 1899 Col. Bingham remarked 
that “Diacamma 9 has been for years a desideratum of Myrmeco- 
logists”, and he adds: “It makes me feel sad to think of the 
many nests I have ruined, the hours of hard labour I have spent, 
and the language I have used inthe futile searchfor 9 Diacamma”. 
He then describes two specimens which he found escaping from 
