Care of the Younp, in the Animal Kingdom. 183 



knowledge as to the development of aphides. Entrust 

 them with eggs of those aphis-species, which their 

 congeners are wont to rear and to nurse. They will 

 treat them as though they had previously "studied" 

 the habits of these aphides! Hence the fondness of 

 certain ant-species for the eggs of aphides is a merely 

 instinctive impulse, which, of course, can be strength- 

 ened by sensitive experience. It was rather rash for 

 Mr. Marshall to proclaim it boldly as ''a faculty of 

 taking the future into account/' Alfred Espinas was 

 far more correct in calling the aphis-nursing of ants 

 an "intelligence non reflechie," i. e., merely analogous 

 to human reason, having but a faint similarity to 

 intelligence proper, the difference being not merely of 

 degree but of kind.^ This analogum rationis is simply 

 an instinctive association of representations, assisted 

 by sensitive experience. 



In spite of the perfection attained in their nursing 

 of plantlice, the Lasius species are far inferior to the 

 Formica species in what modern animal psychology 

 erroneously styles intelligence, viz : in the ability to 

 profit for the future by past experiences. It will be 

 interesting, therefore, to examine, in how far the latter 

 ant-species, in taking care of their offspring, "con- 

 sciously foresee the future." 



Whenever care is taken of the young, then also the 

 future is instinctively taken into account, above all 

 in the rearing of the female ant-larvae; for it 

 depends entirely on modifications in the nursing, 

 whether the fertilized egg will produce a female 

 proper or a worker. But only uncritical popular 



1) "Societes animales" (2d ed.), pp. 157, 188, etc. 



