March, 1919] A Key to Wisconsin Ants 281 



C. herculaneus ligniperda var. noveboracensis Fitch. 



The workers of this beautiful form have a black head and 

 gaster and a dark red thorax. The body surface is rather 

 smooth and shining. 



This species ranges across the continent from the Atlantic 

 to the Pacific, between Nova Scotia, its northern-most limit 

 and Maryland, its southern-most limit. In the Atlantic 

 States it nests at high elevations. It is a wood nesting species 

 also. 



Workers have been found attending Thelia bimacnlata on 

 locust at Madison, Wisconsin. 



Staphylinids found occurring in their nests were identified 

 by Dr. A. Fenyes, of Pasadena, California, as Anomognathus 

 ciispidatiis Fabr. 



C. castaneus var. americanus Mayr. 



These ants are very variable in coloration. The Wisconsin 

 specimens before the writer are reddish brown, with a black 

 head. 



Nets which are built under stones in the woods, contain 

 numerous individuals. 



C. americanus ranges over the Atlantic States and as far 

 west as Texas and Illinois. 



C. herculaneus var. whymperi Forel. 



This form is somewhat variable in coloration, with portions 

 of the body either red or black. The specimens examined were 

 black with the exception of the posterior portion of the thorax, 

 legs and petiole, which are light yellowish red. 



C. whymperi nests at high elevations usually; when found 

 in the lowlands, it occurs in cold tamarack bogs, or the cold 

 woods of the Alleghanies, etc. For the reasons given, it appears 

 to be a Boreal or Alpine form. Their nests, consisting of large 

 colonies, are built in logs and stumps. 



C. fallax var. nearcticus Emery. 



These ants are much more smaller and slender than are 

 those just mentioned. They are smooth, shining black. 



Nests consisting of a few individuals are found under the 

 bark of trees. 



