44 
Psyche 
[June-Sept. 
(3) The foregoing interpretation is supported also by 
the putative parasitism of several other species of Cremato- 
gaster. As early as 1910 I called attention to the species of 
the Ethiopian, Malagasy and Indomalayan subgenus Oxy- 
gyne, in which the females have peculiar falcate mandibles, 
as probably being temporary social parasites in the nests of 
other species of Crematogaster. 1 This statement would 
seem to apply also to two other Ethiopian subgenera, Atopo- 
gyne and Nematocrema. The females of the former have 
large rectangular heads and robust subfalcate mandibles, 
while the females of Nematocrema resemble those of Oxy- 
gyne. Crematogaster acuta Fabr., a rather common Neo- 
tropical species, which Emery regarded as the type of the 
subgenus Crematogaster sens. str. (Santschi’s subgenus 
Eucrema) , has small females, with small gaster like that of 
the worker, and with smooth integument quite unlike that 
of the worker, and is therefore, in all probability, a tempo- 
rary social parasite. More suggestive in this connection are 
two species ( kennedyi and creightoni) of the subgenus 
Acrocoelia which I described recently (1930, 1933) from 
nests of our common North American C. (A.) lineolata Say 
as workerless parasites. Except in possessing well-devel- 
oped wings they are strictly comparable to the females and 
males of the Atitlan colonies. Obviously in all three cases 
we are dealing with parasites that are phylogenetically 
descended from their respective host species and have com- 
pletely lost their worker caste. 2 This derivation seems to be 
more recent in the North American Acrocoelias than in the 
Atitlan form since in the latter both castes have lost their 
wings. The series of other known workerless parasites sug- 
gests that aptery develops sooner in the male than in the 
1 Emery (1897) described and figured an old mother queen of 
Oxygyne ranavalonce Porel of Madagascar as strongly physogastric 
like the old mother queens of Anergates atratulus. 
2 For an account of the considerable number of Aculeate parasites 
that may be derived phylogenetically from their host genera or species 
see my paper of 1919. The parasitic Vespids, Vespula austriaca, 
omissa and adulterina and the parasitic bumble-bees of the genus 
Psithyrus are strictly comparable with the winged workerless para- 
sites among ants belonging to the genera Wheeleriella, Epoecus, 
Labauchena, Pseudoatta, Sympheidole, Epipheidole, Gallardomyrma, 
etc. 
