326 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 2 



during twenty-four hours, the colony would be no weaker at the end of 

 the period than at the beginning, for the workers destroyed would be 

 equaled or exceeded in number by the workers reaching maturity dur- 

 ing the same period within the colony. The futility of methods which 

 do not destroy the colonies, and particularly the queens, is therefore 

 self-evident. 



Winter Trapping 



Reference was made in a preceding article- to the tendency shown 

 by the Argentine 'ant colonies to segregate or combine in the autumn, 

 preparatory to passing the winter as large colonies, containing thou- 

 sands of workers and larvae and dozens, or even hundreds, of queens. 

 These large colonies seek their domicile in well-protected locations 

 favorable for passing the winter. Warm situations are particularly 

 attractive to them. This habit we utilize in the following manner : 

 About the first of October an ordinary dry goods box, about 2x2x3 

 feet, is filled with cotton seed and straw, or other porous vegetable ma- 

 terial, and placed near the center of the ordinary city lot or garden. 

 The top of the box is left exposed to the weather so that the contents 

 will become moist and commence to decay. As deca}^ proceeds the 

 center of the mass becomes very warm and the whole presents a nest- 

 ing situation so attractive to the ants that practicalh' all colonies 

 within a radius of thirty or forty yards take up their abode in it as 

 cool weather approaches. On warm days the ants will be found near 

 the outside of the mass and on cold days nearer the center, as they 

 move inward towards the warmest part until the desired temperature 

 is reached. During January the cracks in the box are closed tightly, 

 the top covered with a waterproof canvas and a pound or two of carbon 

 bisulphide poured into the box to destroy the colony. 



A box of this kind, shown in the accompanying illustration, was 

 prepared in the fall of 1907, not for the special purpose of destroying 

 ants, but for making a small amount of compost for a garden bed. 

 The ants moved into it in such large numbers that the opportunity for 

 destroying them at once presented itself. During the winter this 

 immense colony was examined from time to time and vipwards of 150 

 fertile queens taken from it, together with eggs, larvae and pupae by 

 the cupful as wanted. A conservative estimate placed the number of 

 fertile queens in the colony at upwards of 1,000. The colony in 

 question was not destroyed, as the writer kept it under observation to 

 see "what would happen." He found out. Early in March, 1908, 

 the ants migrated from the box in small colonies and established 

 themselves over the entire premises, with the result that the place was 



^Journal of Economic Entomology, II, p. 191. 



