LENGTH OF LIFE. 9 



tiveh lil-tle change throughout the winter. It is much 

 more difficult to ascertain the length of life of the 

 perfect insect, on account of their gregarious habits, 

 and the difficulty of recognising individual ants. I 

 have found, however, as we shall presently see, that 

 their life is much longer than has heen generally 

 supposed. 



It is generally stated in entomological works that the 

 males of ants die almost immediately. No doubt this 

 is generally the case. At the same time, some males 

 of Myrmica ruginodis, which I isolated with their 

 mates in August 1876, lived until the following spring; 

 one of them till May 17. 



It has also been the general opinion that the 

 females lived about a year. Christ" indeed thought 

 they might last three or even four seasons, but this 

 was merely a suggestion, and Forel expressed the 

 general opinion when he said, ' Je suis persuade qu'en 

 automne il ne reste presque plus que les ouvri^res 

 ecloses pendant le courant de I'ete.' The average 

 life of a queen is also, he thinks, not more than twelve 

 months. I have found, however, that the life of the 

 queens and workers is much longer than had been sup- 

 posed. I shall give further details in a subsequent 

 chapter, but I may just mention here that I kept 

 a queen of Formica fusca from December 1874 till 

 August 1888, when she must have been nearly fifteen 

 years old, and of course may have been more. She 



• Naturgeschichie der Insekten, 

 3 



