80 Bulletin Wisconsin J^aturaJ History Society. [Vol. 5, No. 2. 
the intruders, the Leptothorax workers did not hesitate to 
enter the chamber in which the Myrmicas had taken up their 
abode. There they ran about, accosting the Myrmicas, which 
had gorged themselves with the sugar water in the manger in one 
of the corners of the chamber. The Leptothorax mounted their 
backs, shampooed their bodies and then, turning to the ventral 
side, promptly placed their tongues in contact with those of their 
host and imbibed the regurgitated sweets. The shampooing, how- 
ever, was of much briefer duration and much more perfunctory 
than in the colonies of the typical emersoni. Often the glacialis 
worker omitted these manipulations altogether and went at once 
to the mouth of its host. Sometimes as many as five or six of the 
little ants would remain standing on the floor of the nest and 
drink simultaneously from the tongue of a single Myrmica. If 
the host failed to proffer the droplet of food, the Leptothorax 
would usually pinch her fore leg or antenna, and this more 
emphatic and probably more painful appeal rarely failed to elicit 
the desired response. The Leptothorax undoubtedly obtained all 
of their food from their hosts, for during the entire six weeks 
they were under observation, I never found one of them eating 
from the manger, or even showing the slightest interest in its 
contents. In the privacy of their own quarters, however, they 
freely fed one another by regurgitation with the food they had 
obtained from the Myrmicas. 
As by July 20th the Leptothorax had shown no disposition to 
move their brood into the dark chamber with the Myrmicas, I 
undertook to coerce them by exposing their quarters to the bright 
sunlight. Even this had no effect, till the glass roof-pane became 
heated, when they slowly and reluctantly took up their larvae and 
pupae and migrated into the dark chamber. Then the entrance 
between the two chambers was closed. I expected the Leptothorax 
to establish themselves in one of the larger cavities of the sponge, 
as had been done by some of my colonies of the typical emersoni, 
but they merely stacked their brood in three piles at the end of the 
sponge. Here they were, of cours.e, fully exposed to the Myrmica 
workers and the latter began to visit them assiduously. The 
