SUPPOSED USE OF PASS SIGNS. 127 



municating to their comrades what they purpose is 

 peculiar to insects. Much has been talked of the 

 Bo-called signs of recognition in bees, which is said to 

 consist in recognising their comrades of the same hive 

 by means of pecuHar signs. This sign serves to pre- 

 vent any strange bee from entering into the same hive 

 without being immediately detected and killed. It, 

 however, sometimes happens that several hives have 

 the same signs, when their several members rob each 

 other with impunity. In these cases the bees whose 

 hive suffers most alter their signs, and then can im- 

 mediately detect their enemy.' ' 



Others, again, have supposed ants recognise one 

 another by smell. 



Mr. McCook states that ants more or less soaked in 

 water are no longer recognised by their friends, but, on 

 the contrary, are attacked. Describing the following 

 observation, he says : ^ — ' I was accidentally set upon the 

 track of an interesting discovery. An ant fell into a 

 box containing water placed at the foot of a tree. She 

 remained in the liquid several moments and crept out. 

 Immediately she was seized in a hostile manner, first 

 by one, then another, then by a third : the two an- 

 tennae and one leg were thus held. A fourth ant 

 assaulted the middle thorax and petiole. The poor 

 little bather was thus dragged helplessly to and fro 

 for a long time, and was evidently ordained to death. 



' Burmeister's Entomology, p. 502. 



* Mmnd-vuiking AnU of the AUeghaniet, p. 280. 



