300 
Psyche 
[December 
(a) That there is indeed a sharp behavioral distinction between 
“home” and “alien” populations, and 
(b) That R. metallica is sufficiently aggressive so that a simple 
confrontation of such “alien” workers, in the field, in the artificial 
nest, or simply in such “arenas” as laboratory finger bowls is suffi¬ 
cient to elicit sharp and unmistakable reactions at once. Thus, while 
observations involving compatibility reactions within and between 
colonies of some hypogeaic or semi-hypoeaic Ponerinae (such as 
members of the genus Amblyopone) must be undertaken with great 
care, and should be conducted within arenas, such as artificial nests, 
which are thoroughly familiar to the subjects and preferably have 
been occupied by them for many months beforehand, such precau¬ 
tions appear unnecessary with this active, aggressive epigeaic ecta- 
tomiine. 
Three well-separated Australian populations of R. metallica were 
selected for the investigation. The first group was drawn from a 
rather small area in Southern Queensland, bounded by a rough 
triangle marked by the towns of Nambour, Montville, and Para¬ 
mount Point, in the coastal Blackall Range. Nambour is approxi¬ 
mately 59 miles north of Brisbane, and the distance between 
Nambour and Montville is approximately 7 miles. A second popula¬ 
tion was drawn from a limited area in Ashton Park,* a municipal 
reserve on the outskirts of Sydney, N.S.W. separated by an arm of 
Sydney Harbor, and located approximately 560 miles from the 
Nambour-Montville region. This Ashton collection area included a 
roadside strip approximately one-half mile in greatest length by 
some sixty feet in width. The third area was located outside of the 
town of Sutherland, N.S.W., near the proximate border of the 
National Park of New South Wales, separated from the Ashton 
population by approximately 20 miles. It included strips of roadside 
verge approximately three miles in length by one-half mile in width. 
Colonies were collected from these areas in 1959, 1963, 1968, 
1973, and 1977, and maintained in the laboratory in glass earth- 
filled Lubbock-type nests, kept in arenas where workers could for¬ 
age at all times. Some individual colonies were maintained con¬ 
tinuously under these conditions for as long as 14 years, so that, 
when desirable, reactions could be tested of workers more than one 
“generation” removed from the group originally collected. 
Now Sydney Harbor National Park 
