fielde] COMMUNAL LIFE OF ANTS 247 



Worker ants of the same community enjoy each other's odor, 

 lick and pat each other, cuddle, and exchange nourishment by 

 regurgitations. They take care of the young, the product of the 

 queen's eggs or of their own eggs, with no manifest partiality 

 except for the largest. If their nest be raided by alien ants or 

 prowling human creatures, the workers, if there be leisure for 

 choice among the immature young, will flee with the oldest, the 

 objects on which most labor and care have already been expended. 

 The rearing of the young is a constant occupation which is fol- 

 lowed with an amazing diligence by the workers. The defense 

 of the nest is also constant, and intruders are attacked with a 

 ferocity equal to that shown by any other creature in defense of 

 its offspring. I have seen two ants battle through eighteen con- 

 secutive hours. 



Food is brought to the nest from distances extending to forty 

 yards or more. When an ant goes out it lays a path under its 

 feet, and in returning it follows its own scent as laid down. If 

 the path be washed or overturned for a space longer than the body 

 of the ant, the returning traveller loses the way and runs to and 

 fro until the scent is picked up. This scent is perceived through 

 the air ; for a very thin layer of earth may be made to overlay 

 the path without it interfering with the traveller's homeward 

 progress. Every ant lays down and pursues an individual path ; 

 but like causes, such as shade, temperature, or topography may 

 impel a multitude of ants into the same route. 



Ants probably orient themselves on their journeys by the sense 

 of smell, as a blind man might orient himself on a known road 

 by a compost-heap, a glue-factory, a hop-field and a rose-garden. 

 But these directing odors come from very short distances, prob- 

 ably less than an inch at most. When ants go forth from the 

 nest, they sometimes go back repeatedly, gradually extending 

 their journey, and appearing as if trying to familiarize themselves 

 with their means of orientation. The path laid down by an ant, 

 if left dry and undisturbed, may be followed by her unhesitatingly 

 after five days of imprisonment elsewhere. 



Insects have had few tests applied to their power of memory, 

 the shortness of insect life being generally preventive of long con- 

 tinued experiments in proving their mental capacities. Among 

 the insects, ants are remarkable for longevity, and they therefore 

 present exceptional possibilities for the work of the comparative 



