42 LONGEVITY OF ANTS. 



a few days, dying between the 16th and 20th. These 

 two ants, therefore, must have been five years old at 

 least. It is certainly curious that they should, after 

 living so long, have died within ten days of one 

 another. There was nothing, as far as I could see, in 

 the state of the nest or the weather to account for this, 

 and they were well supplied with food ; yet I hardly 

 ventiure to suggest that the survivor pined away for 

 the loss of her companion. 



Some workers of F. cinerea lived in one of my 

 nests from November 1875 to July 1881. 



In a nest of F.fusca, which I brought in on June 

 6, 1875, and in one of Lasius niger brought in 

 on July 25, 1875, there were no queens; and, as 

 already mentioned, no workers have been produced. 

 Those now living (December 1881) are therefore the 

 original ones, and they must be more than six years 

 old. 



The duration of life in ants is therefore much 

 greater than has been hitherto supposed. 



Though I lose many ants from accidents, especially 

 in summer, in winter there are very few deaths. 



I have given the following figure (fig. 2), which 

 represents a typical nest belonging to Lasius niger^ 

 because it is a good instance of the mode in which 

 my ants excavated chambers and galleries for them- 

 selves, and seems to show some ideas of strategy. The 

 nest is, as usual, between two plates of glass, the outer 

 border is a framework of wood, and the shaded part 



