1965] 
Haskins and Whelden — Rhytidoponera 
103 
closely watched and timed. Pairs remained in copula from a minimum 
of 30 seconds to a maximum of 52 seconds. It was noted with special 
interest that in one case the same pair copulated twice; in another an 
individual male paired successively with two workers. In two instances 
workers reentered the parent nest while still in copula. 
All males observed sustained active flight for periods up to one 
half hour before seeking to copulate. The final stages of search, 
however, were accomplished in every case on the ground. The whole 
process was suggestive of the mating pattern observed in certain 
Ponerine species (such as Amblyopone australis and A. ( Stigmatom - 
ma) pallipes — Haskins and Haskins, 1951; Haskins, 1928) where 
the alate female flies only occasionally and with reluctance but 
emerges from the parent colony to mate on the ground or on low 
vegetation. The vigorous pattern of dispersive flight and the general 
hyperactivity of the males during the flights seemed conspicuously 
adapted to securing outcrossing between colonies of the species. Such 
outcrossing, indeed, may be biologically essential, as will later be 
indicated. 
No detectable morphological features distinguished workers which 
mated from those which did not. The group which was fertilized 
included both among the smallest and among the largest individuals 
in the population, as well as many in an intermediate range. This 
observation confirms the conclusion of Whelden (1957; i960) derived 
from his histological investigations, that workers showing sperm 
content in the spermatheca included individuals of a wide range of size. 
A second nuptial flight of identical pattern was observed in this 
nest on January 27, 1957. Shortly after 9:00 A.M. of that day male 
exodus and flight began in typical fashion, reaching a peak by 10:30 
A.M. On October 17, 1952, July 17, 1953, and November 22, 1953 
workers of this colony were again observed resting outside the nest 
with gasters elevated, but on these occasions there was no correspond- 
ing flight of males. Precisely this same behavior of workers has been 
observed with colonies of Rhytidoponera tasmaniensis , R. inornata, 
and R. violacea , all housed in the usual type of modified, earth- 
containing Lubbock nests. The intervals for which the position was 
maintained were similar to those in R. metallica. Males have been 
seen to fly actively from a nest of R. violacea , closely simulating the 
pattern of flight in metallica. Actual mating has not been observed 
in these species, but it seems a probable inference that the pattern 
is similar. 
Explanation of Plate 6 
Late male Pupae of Rhytidoponera purpurea, from Brood Matured in 
Artificial Nest in Fragment Without Brood Queen. 
