LONGEVITY OF ANTS. 4l5 



have not myself been able to repeat the observation 

 with the same species, but with two at least of our 

 native ants the results were exactly reversed. In one 

 case five specimens of Lasius niger fell into water and 

 remained immersed for three hours. I then took them 

 out and put them into a bottle to recover themselves. 

 The following morning I allowed them to return. They 

 were received as friends, and though we watched them 

 from 7.30 till 1.30 every hour, there was not the 

 slightest sign of hostility. The nest was moreover 

 placed in a close box, so that if any ant were killed we 

 could inevitably find the body, and I can therefore 

 positively state that no ant died. In this case, there- 

 fore, it is clear that the immersion did not prevent 

 them from being recognised. Again, three specimens 

 of Formica fusca dropped into water. After three 

 hours I took them out, and after keeping them by 

 themselves for the night to recover, I put them back 

 into the nest. They were unquestionably received as 

 friends, without the slightest sign of hostility, or even 

 of doubt. I do not, however, by any means intend to 

 express the opinion that smell is not the mode by 

 which recognition is effected. 



Longevity. 



It may be remembered that my nests have enabled 

 me to keep ants under observation for long periods, 

 and that 1 have identified workers of Lasius niger and 

 Formica fusca which were at least seven years old, 

 and two queens of Formica fusca which have lived 

 with me ever since December 1874. One of these 

 queens, after ailing for some days, died on July 30, 

 1887. She must then have been more than thirteen 

 years old. I was at first afraid that the other one 

 might be afi'ected by the death of her companion. She 



