386 Bulletin American Museum of Natural History. [Vol. XXI, 



Tetramorium Mayr. 



38. T. caespitum Linn. — Camden Co. (Daecke). — I have seen 

 this species, the "lawn ant," only at Fort Lee. It is evidently 

 imported from Europe and seems to be making but slow progress 

 over the country. It occurs northward and eastward of New 

 York as far as the Connecticut boundary, westward as far as 

 Philadelphia, and southward as far as Virginia. Emery mentions its 

 occurrence also in Tennessee and Nebraska, but I have never been 

 able to find it in the Middle West. 



Strumigenys F. Smith. 



39. S. pergandei Emery. — This and the two following species are 

 known to occur in Pennsylvania, and will doubtless be found also in 

 New Jersey. They are all very rare ants and nest in the ground, 

 often in plesiobiosis with larger species (Formica, etc.). 



40. S. pulchella Emery. 



41. S. clypeata Roger. 



Atta Fahricius. 

 (Subgenus Trachymyrmex Forel.) 



42. A. (T.) septentrionalis McCook {= f tardigrada Buckley). — 

 Vineland (Mrs. M. Treat, McCook); Toms River (Morris); Lake- 

 hurst (Wheeler). 



This species, called the "northern cutting ant" by McCook, is the 

 only one of the North American Attii, or fungus-growing ants, whose 

 range extends into the Northern States. It is abundant in the pine 

 barrens about Lakehurst, nesting in pure white sand. It moves 

 very slowly and is so timid that it retreats into its nest at the slightest 

 alarm. The nest is not easily found except during the spring and 

 autumn when the ants are actively excavating. At such times one 

 may find a circular nest-entrance about three sixteenths of an inch 

 in diameter and an inch or two to one side of it a pile of sand brought 

 out by the workers. The entrance leads into an oblique gallery 

 which widens at intervals into two or three spheroidal chambers 

 varying from 1-2 inches in diameter. Sometimes these chambers 

 form the blind terminations of two or three different galleries branch- 

 ing off from the main or entrance gallery. The rootlets of plants 

 are left spanning the chambers and from these fibrous supports the 



