1965] 
Haskins and Whelden — Rhytidoponera 
89 
along a belt down the eastern edge of Australia at least as far as 
south central Victoria (Brown, 1958). 
In a second and much larger group of Rhytidoponera species, an 
exactly opposite situation obtains with respect to the queen. Many of 
these species include among the largest and most conspicuous members 
of the genus, are widely distributed, abundant, and well known, 
especially in the drier areas of Australia, and have been extensively 
collected over long periods. Yet in none of them has a reproductive 
morphologically or functionally distinguishable from a normal worker 
ever been described. 
Finally there is a third group, designated by Brown (1958) the 
Rhytidoponera metallica complex, which may be the most interesting 
from the standpoint of social evolution. The type species is one of the 
most widely distributed and ubiquitous of Australian ants; an inhabit- 
ant of thickly populated as well as remote situations over a very large 
area both temperate and subtropical; and so familiar as to have been 
known to a wide public for many years by the popular name of 
“greenhead” ant. Alate typical queens of this species have been 
described, and are represented in limited numbers in some collections, 
notably that of the Harvard Museum of Comparative Zoology. 
Wheeler described a single dealate and possibly colony-founding 
female of R. inornata, a member of the complex from southwestern 
Australia in 1931 (Brown, 1958). Brown (1958) has described a 
dealate female of another related species, R. aspera , collected by 
H. Hacker in southeastern Queensland and also in the Harvard 
Museum of Comparative Zoology. A single perfect female of R. 
victoriae, taken by Brown at Seaford, Victoria, is in the same col- 
lection. But it is striking that so few typical females have been 
identified in a complex of species as extraordinarily abundant and 
well-collected. It is clear that the vast majority of colonies in nature 
must exist without such females. 
Even more interesting is the fact that in no species of Rhytidoponera , 
including those of the metallica complex, has a queen-worker inter- 
mediate ever been recorded. This could suggest that evolution to the 
loss of the typical female took a somewhat different course from that 
in the Lobopelta-Leptogenys complex or even in Heteroponera. 
Instead of the alate female reproductive being morphologically modi- 
fied toward a stabilized intermediate between queen and worker while 
continuing the same functional role in the colony, the original queen 
caste may have disappeared entirely and one or more laying workers 
substituted as the usual reproductives. If, as Carroll Williams (in 
Brown, i960) has suggested, worker development in ants is due to a 
