1915] 



Mann — Southern Ant from Naushon hiand 



51 



A NEW FORM OF A SOUTHERN ANT FROM NAUSHON 

 ISLAND, MASSACHUSETTS. 



By Wm. M. Mann, 

 Bussey Institution, Harvard University. 



In August, 1915, Mr. F. X. Williams and I spent part of a day 

 collecting on Naushon Island, opposite Woods Hole, Mass. 

 Among other insects characteristic of more southern regions we 

 found several colonies of a large Apha^nogaster, which were nesting 

 beneath large stones on the tops of low hills near the shore. This 

 proves to be an undescribed subspecies of Aphcenogaster treatoe 

 Forel, a species which, with its variety ashmeadi Emery, is found 

 throughout the South Atlantic states and as far north as Connec- 

 ticut. This occurrence on Naushon Island is an addition to the 

 long list of insects and plants typical of the southern coastal 

 region which occur also at isolated points on the north coast, as 

 relicts of the ancient costal plain fauna and flora. 



The subspecies may be characterized as follows: 



Aphaenogaster treatae Forel subsp. wheeleri uov. 



Worker: Similar to treatoe in form, sculp- 

 ture and pilosity, but differs in having the 

 lamellae at the base of antennal scapes broadly 

 angulate in front, instead of evenly rounded. 

 The color is much darker, being dark fuscous, 

 with the front of head and the gastric dorsum 

 piceous. 



Female: Differing from treatae in the 

 following characters. The color is dark 

 fuscous to piceous. The antennal lamellae 

 are very noticeably angulate in front. The 

 epinotal spines are longer and less broad 

 at the base. The wings are more deeply 

 infuscated. 



Fig 

 Forel. 



subsp. ivheeleri 

 treatce Forel. 



1. Aphaenogaster treatce 



a, antennal lamella of 



nov.; b, same of 



Described from two females and numerous workers. 



The darker coloration is very noticeable and constant in a large 

 series of the new subspecies, compared with manj' specimens of 

 the typical treatoe from various localities. 



