Introduction. 5 



already, on another occasion/ been subjected by us to 

 a thorough discussion. Besides, in a longer essay, 

 especially intended for professional zoologists,^ we have 

 since then perfected our former argument, proving 

 that ants are no more mere reflex machines than dogs 

 and apes are intelligent beings. The theoretical side of 

 Bethe's psychological views was also noticed in the 

 second edition of our essay ** Instinct and Intelligence 

 in the Animal Kingdom" (chapters 7 and 8).^ In this 

 work, therefore, we shall return to them but occa- 

 sionally, to show the fatal results of attempting to 

 vindicate the intelligence of higher animals by com- 

 pletely denying psychic activities in ants. 



1) "A new reflex theory of ant life" (Biolog. Centralbl., XVIII, 

 1898, n. 15, p. 577-588). 



2) "Die psychischen Faehigkeiten der Ameisen," Stuttgart, 1899. 

 ("Zoologica," Heft 26) p. 134 and' foil, with 3 plates. 



s) p. 144 and following. 



