156 PROCEEDINGS OF THE ACADEMY OP [1879. 



galleries as usual, while others dropped them near the mouth or 

 door. The evening was quite cool and Mr. McCook's impression 

 was that the ants who dropped the pellets within or just outside of 

 the doors were probably caused to do so by the sense of cold with 

 which they were met. Feeling the cold air as they approached 

 the gate, instead of pushing out, they stopped, dropped the pellet, 

 and turned back. Thus the grains accumulated, giving the ap- 

 pearance of an intentional closing. Through the doors which were 

 nearty closed an ant head and antennas could occasionally be seen 

 peeping forth. 



May 27. 



The President, Dr. Ruschenberger, in the chair. 



Thirty-four persons present. 



Charles H. Pennypacker and Robert S. Davis were elected 

 members. 



June 3. 

 The President, Dr. Ruschenberger, in the chair. 

 Twenty-one members present. 



June 10. 



The President, Dr. Ruschenberger, in the chair. 



Fifteen persons present. 



The deaths of Wm. W. Longstreth and F. F. Maury, M.D., 

 members, were announced. 



Combats and Nidification of the Pavement Ant, Tetramorium 

 Csespitum. Mr. McCook. exhibited a large glass jar containing a 

 nest of this ant made by captives taken from a city garden. Dur- 

 ing the month of May immense numbers of this species have been 

 seen along our sidewalks, in yards and gardens, engaged in com- 

 bat. From one of these masses of struggling insects, three large 

 groups were taken and placed in separate jars. The transfer had 

 no visible effect in separating the combatants. Into one jar (No. 

 1) a pellet saturated in cologne was introduced. Instantly, as in 

 the case of experiments previously reported, 1 the combatants 

 separated, and buried themselves pell-mell in the earth. Not an 



1 Mode of Recognition among Ants, Proceed. Acad. Nat. Sci., p. 15, 

 1878. 



