IHE 
AMERICAN “NATURALIST 
Vor. XXXV. July, rgor. No. 415. 
THE COMPOUND AND MIXED NESTS OF 
AMERICAN ANTS. 
WILLIAM MORTON WHEELER. 
Part II. Tue Known Cases or SociAL SYMBIOSIS AMONG 
AMERICAN ANTS. 
SOCIAL symbiosis among ants occurs in what are called 
“compound " and “mixed” nests. These terms are used in 
the sense of Forel's * fourmiliéres doubles " and * fourmiliéres 
mixtes" The former are defined (74, p. 52) as “ nests inhab- 
ited simultaneously by two or more ant colonies belonging to 
two or several hostile species." The latter term was adopted 
by Forel from Pierre Huber (10). It includes the nests which 
are amicably inhabited in common by ant colonies belonging 
to different species. Both categories were later accepted by 
Wasmann (91) with slight changes, and, somewhat more 
accurately, designated as “zusammengesetzte Nester und 
gemischte Kolonien" (compound nests and mixed colonies). 
Wasmann included all the various forms of compound and 
mixed nests known in 1891 in the following table (91, 
PP. 176—178): 
513 
