1904.] NATURAL SCIENCES OF PHILADELPHIA. 639 



THREE ODD INCIDENTS IN ANT-LIFE. 



BY ADELE M. FIELDE, 



1. A case of hypnotism among ants? 



I had a small artificial nest containing twelve workers of Cremasto- 

 gaster lineolata that had spent the first month of their lives in a mixed 

 colony of Lasius latipes, Stenamnia fiilvum and their own kind. They 

 had then been transfeiTed to their present abode, where they had lived 

 for eleven months, never meeting ants of other species, except upon a 

 few rare occasions when I introduced a visitor into their nest. On 

 August 20, 1904, they were happily occupied in care of some promising 

 pupae from their old wild nest, when I dropped into their nursery a 

 single Lasnis latipes, somewhat larger and probably older than any of 

 their number. She was a stranger from the wild nest of their quondam 

 associates. As I dropped the strong-smelling, vigorous yellow worker 

 into their nest, I glanced at my watch to note the minutes they would 

 spend in slaying the intruder. When I looked back at the ants, I was 

 at once impressed by the curious and sudden change in the positions 

 of all the little black Cremastogasters and by the remarkable rigidity 

 of five of them. Five were in the food-room, and they do not enter 

 further into this narration ; two were on the roof-pane of the nursery ; 



and five were motionless under the 

 touches of the Lasius, who, instead of 

 fleeing or hiding, as do ants who are 

 among enemies outnumbering them, was 

 traversing two sides of the nursery at a 

 leisurely-rapid pace from the hallway, 

 marked H, to the corner marked A 

 where there was a little pile of pupse, 

 and then on to the B corner where 

 was a similar pile. She made more than 

 eleven journeys to and fro, taking nearly 

 The straight lines indicate the the same track, sometimes walking Over 

 sides of the nest; the dotted line j^j^ ^j-^^ qj. two, sometimes brushing the 

 the path of the yellow ant; the ., . , , 4.- „„ 



dashes the positions of the five Side of one as she passed, sometnnes 

 black ants. slightly varying her route so as to pass 



between two on the A B side of the nest. Whatever her course, every 

 ant of the five swayed the abdomen slowly toward her as she passed, 

 and swayed it back as soon as she had passed it. This swaying of the 



H -:^....A 



B 



