March, 1919] A Key to Wisconsin Ants 283 



Subgenus Acanthomyops Mayr. 

 L. (A.) interjectus Mayr. 

 The workers of this species are yellow and robust, with an 

 agreeable body odor somewhat similar to that of lemon verbena. 

 This is the largest species of the genus. 



Nests are built under stones, in logs or in stumps. The 

 workers which are very numerous in the colonies attend aphids 

 underground. 



L. (A.) claviger Roger. 

 This species is smaller than L. interjectus and possesses 

 abundant long hairs on the gaster. The lemon verbena like 

 odor is also present about the workers. 



L. claviger is the most abundant species of the subgenus 

 Acanthomyops . It nests under stones. 



L. (A.) latipes Walsh. 

 Females of this form are dimorphic. One of the forms 

 being very hairy and possessing much flattened femora and 

 tibiae. 



Nests are constructed under stones. 



Genus Prenolepis Mayr. 

 P. imparls Say. 



This species is the largest ant of the genus, measuring from 

 3-4 mm. in length. It is also the most widely distributed, 

 ranging from the Atlantic to the Pacific in the Transition Zone. 

 The typical form is dark brown, while the variety is much 

 smaller and paler. 



The workers are exceedingly fond of sweets, aphid excre- 

 tions, etc., and are very commonly found attending aphids, 

 coccids, and membracids. When the workers are full of 

 honey dew, their abdomens are very much distended; this when 

 they are walking gives them the appearance of swaggering like a 

 drunken man. 



This species has been observed to be much of a house pest in 

 the South Atlantic States. 



Their nests, which are located in moist clay like soils, are 

 small craters made of irregular pellets, which resemble the 

 pellets of the ants of the subgenus Trachymyrmex. A colony 

 consists of from 300 to 400 individuals. The males and females 

 pass the winter in the colony nest and take their nuptial flights 

 early in the spring. 



