4 
Psyche 
[March 
groups utilized separate areas for nest sites, but each 
permitted the other within its own area. The provancheri 
workers were seen to “shampoo” the backs and heads of 
fracticornis workers and females and to receive regurgi- 
tated food in return just as Wheeler (1901) had observed 
to occur between provancheri and brevinodis. The pro- 
vancheri and fracticornis workers were also observed 
feeding together on honey, syrup, and water that was 
placed in the chambers, but only the fracticornis workers 
were seen to feed upon the bodies of freshly killed insects 
(roaches, flies, lacewing-flies, and collembolans) that were 
also introduced into the nest. 
From the above observations it seems evident that pro- 
vancheri is in an early stage of social parasitism as in- 
dicated by its ability to live independently in part of its 
range, whereas in other parts it requires the presence of 
Myrmica nests. In those areas where it lives as an in- 
quiline it is also probable that the colony-founding female 
seeks first a suitable environment (one that is both moist 
and cool), and, once there, seeks a Myrmica nest. In 
Michigan bogs the choice of Myrmica nests in the open 
mat zone is largely restricted to brevinodis and fracti- 
cornis. 1 In other areas (North Dakota, for instance) 
Myrmica brevispinosa Wheeler may occur in the same or 
similar environments as those occupied by brevinodis and 
fracticornis. The rarity of provancheri and fracticornis 
combinations may indicate that fracticornis tolerates the 
inquilines less frequently than brevinodis does. The sim- 
ilarity of the behavior of fracticornis and brevinodis in 
response to the “shampooing” by the provancheri workers 
suggests that this behavior pattern may be common to 
other more closely related species of Myrmica. 
1 A third species of Myrmica of uncertain identity is also present in 
southeastern Michigan bogs. 
Literature Cited 
Cole, A. C. 
1954. Studies of New Mexico ants. X. The genus Leptothorax 
(Hymenoptera : Formicidae). Jour. Tenn. Acad. Sci. 29 (3): 240-241. 
