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Psyche 
[Vol. 93 
Banyuls (no 2a) and along the Spanish Pyrenees (no 2c, 3b, 3d), we 
found a few colonies with 15 to more than 20 £.-$$, which would 
be sufficient for an effective slave-raiding. As was suggested for E. 
kraussei from Tignale (Buschinger & Winter 1983), however, we 
believe that slave-raids do occur only exceptionally, if at all, in the 
other populations now studied: Most colonies comprise but very 
few E.-QQ, and colonies with higher E.-Q -numbers on average do 
not contain more host species workers than those with few or no 
E. -QQ. From table 6 we may conclude that Epimyrma kraussei has 
established numerous local populations in which the reduction of 
$ -numbers has occurred to highly variable degrees. The population 
ascribed to E. vandeli then would be close to one end of the scale 
which is complete loss of the £ -caste like in E. Corsica (Buschinger 
& Winter 1985), and E.foreli is among the populations with highest 
F. -$ -numbers. It must be stated, however, that a geographical vari- 
ation of 5 -numbers, e.g., in the sense of a cline, is lacking: Popula- 
tions with low $ -numbers have been found in S ’France (no 5a, E. 
vandeli) and in N’Spain (no 3a), and high $ -numbers occur close to 
the latter locality (no 3b) as well as in S ’Italy (no 19, E. foreli). 
In laboratory culture the $ -production of Epimyrma colonies 
roughly corresponds to the field data. Table 7 provides a compari- 
son of 5 -production in colonies from 3 populations. Most impor- 
tant is the fact that appeared in 2 of the 5 laboratory-kept 
colonies from population no 5a (Lauzerte, E. vandeli). 
Worker numbers, thus, are not contradictory to a synonymiza- 
tion of E.v. and E.f. with E. kraussei. 
Crossbreeding experiments 
Intranidal mating is an excellent condition for experimental 
crossbreeding of sexuals from different populations and even spe- 
cies. Colonies are kept in nearly natural annual cycles with a long 
hibernation of about 6 months at 10° C a “spring” and “fall” phase 
in daily temperature rhythms of 10°C (12h, dark) and 20° C (12h, 
light) for 2 weeks each, and a summer phase of 15°C (lOh, dark) and 
25° C (14h, light) for 2 weeks, followed by 2 months of 17°C (lOh, 
dark) and 28° C ( 14h, light), and again 2 weeks of 1 5° C/ 25° C when 
pupation decreases. For details of formicaries, feeding etc. see 
Buschinger (1974). All $ pupae from colonies of 2 populations or 
species are exchanged. Further $ pupae arising newly from the 
