100 
Psyche 
[March 
Number 
Per Cent 
Number 
Individuals 
Individuals 
in 
with 
with 
Species 
Sample 
Sperm 
Sperm 
R. metallica 
386 
21 
54 
R. inornata 
176 
4 
2.3 
R. violacea 
274 
22 
8.0 
It thus seems clear that thelytokous parthenogenesis at least is not 
usual in these species of Rhytidoponera , and that a normal mechanism 
of fertilization is involved in the production of worker progeny. Other 
questions concerned with an estimate of the average relatedness among 
workers in a single Rhytidoponera colony, earlier posed, are thus 
raised. It becomes important, for example, to ascertain whether 
single or multiple insemination of workers is the rule, whether 
individual workers may be inseminated more than once during their 
lifetimes, and to what degree outcrossing among different colonies 
obtains. These issues, of course, can only be determined by careful 
and complete observations of the mating flight. Our observations are 
still very incomplete. Since, however, they have provided answers 
to one or two such questions, even at this preliminary stage, they are 
presented here. 
CHARACTER OF THE MATING FLIGHT IN 
RHYTIDOPONERA METALLICA 
Some field evidence of the fertilization of workers by males in 
Rhytidoponera metallica has been obtained by W. L. Brown, Jr. 
(unpublished observations). He noticed males in low flight which 
alighted and entered the main gallery of an established nest of the 
species. There seems to be no observational record, however, of actual 
fertilization of workers. We have been so fortunate as to witness this. 
A colony of R. metallica cited earlier in another connection, was 
collected at Sutherland, N. S. W., Australia, on June i, 1952. As 
already described, it was housed in a modified earth-containing glass 
Lubbock nest, and was then maintained for three months at I5-I7°C, 
within the normal winter temperature range of its environment. 
During this period workers were allowed to forage from the nest in 
a closed arena, and were supplied dilute honey continuously and 
provided frequently with a considerable variety of living insect prey. 
On September 3, 1952, the nocturnal temperature was raised to 2Q°C, 
and diurnal temperatures were allowed to reach a maximum of 25 °C. 
Two days after this temperature rise, a number of males which had 
matured in the nest during the cool period left it and wandered over 
