TRANSLATOR'S PREFACE. 



YTTASMANN'S "Instinct and Intelligence in the 

 VV Animal Kingdom," which appeared recently in 

 an English dress (Herder, St. Louis, Mo.), was so 

 favorably received, that it has been thought advisable 

 to follow it up with this translation of another essay 

 by the same author. These two books supplement 

 each other, as may be gathered from the frequent 

 cross references they contain, and, more especially, 

 from the close relationship of the subjects of which 

 they treat. 



The best recommendation of Wasmann's biological 

 and psychological essays is given in the following- 

 lines of W. M. Wheeler, Prof, of the University of 

 Texas :* "Wasmann in his numerous writings has 

 undoubtedly done much, at least in Germany, towards 

 the exposure of this pseudo-psychology (of Brehm, 

 Buechner and others) and a more rational conception 

 of ant behavior. His long familiarity with these 

 animals and their guests has given him a singularly 

 lucid insight into their activities. My own more 

 limited observations on our North American species 

 lead me to agree with him so far as the facts are con- 

 cerned, and many of the inferences which he has 

 drawn from them." As to his additional remark: 

 "I am constrained to say, however, that I cannot adopt 



*) "The Compound and Mixed Nests of American Ants," in 

 "American Naturalist," Vol. XXV, 1901, p. 808. 



