I IO 
Psyche 
[March 
coexist in normal colonies of at least three species of Rhytidoponera. 
Further, in R. metcillica at least, multiple insemination of workers, 
and insemination by individual males of more than one worker are 
not uncommon. It is also evident that workers can and do make rich 
contributions of male progeny, which may begin to appear (in small 
numbers) very early in the life of an isolated, expanding, worker 
group. All these circumstances make it seem improbable, at first 
glance, that an average degree of relatedness among members ap- 
proaching sibship can be maintained in a typical Rhytidoponera 
colony. The situation might be quite different, however, if a single 
fertile individual normally dominated oviposition in a colony, rival 
fertile individuals being suppressed by hormonal or behavioral means. 
Whether any such situation obtains remains to be determined. 
If the relatedness of workers within a single colony is indeed 
relatively low (at least not consistently maintained at the sibship 
level), it may well be that among the members of a continuous 
population of the species it is more than usually close. For if new 
communities normally arise from small parties containing at least one 
fertilized worker which leave parent colonies, it seems probable that 
the average distance traveled before settling down would be consider- 
ably less than that covered by actively flying queens before founding 
new communities. One might indeed expect the Rhytidoponera 
population to be considerably more ‘Viscous,” in Hamilton’s term, 
than those of such an ant genus as Lasius, and might perhaps reason- 
ably expect a lesser degree of “colony integrity” than in a monogynous 
species with actively flying alates of both sexes. Some measure of the 
degree of colonial integrity developed among those Rhytidoponera 
species normally without alate females might be gained by a careful 
study of “colony recognition” between communities — of the degree 
of worker-to-worker hostility among individual colonies of the same 
population, as compared to that between colonies from populations 
considerably separated geographically. Work of this character is 
planned. 
References 
Brian, M. V. 
1959. The ontogeny of insects. Acta symposii de evolutione insectorum, 
Praha, 167-171. 
1961. Organ transplants between ant castes. Symposia Genetica et. 
biol. it., Atti IV Congresso U.I.E.I.S., Pavia, 9-14, Settembre. 
Brown,,, W. L., Jr. 
1954.- Systematic and other notes on some of the smaller species of the 
ant genus Rhytidoponera Mayr. Breviora (Harvard Mus. Comp. 
Zool.) 33: 1-11. 
