182 Chapter IV. 



made, e. g., by William Marshall in his "Leben und 

 Treiben der Ameisen" (p. 102), where he speaks of 

 the care given by ants to the eggs of plantlice. Sev- 

 eral ant-species of the genus Lasius collect the eggs 

 of certain Aphides in their nests. Being carefully 

 protected during winter, the young aphides in spring 

 are carried to the plants on which they find their food. 

 Thence Marshall infers, that the ants tend the eggs 

 with the intelligent purpose of enjoying later on the 

 sweet secretions of the aphides. "This is surely a 

 very strange phenomenon," he says, "which proves 

 perhaps better than anything else the high degree of 

 intelligence attained by ants. We must credit them 

 with a considerable power of observation, and we must 

 own, that they have studied, to a certain degree, the 

 habits of their domesticated animals," etc. Yet this 

 bold conclusion is entirely unfounded. How does 

 Marshall know, that the ants gather the eggs of the 

 aphides with the intelligent purpose of rearing 

 aphides? That there is some connection between the 

 eggs of the aphides and the aphides themselves is, 

 indeed, for many ants a subject of sensitive knowl- 

 edge and experience; but it is unwarrantable to mis- 

 take this process of instinctive association for intelli- 

 gence proper. Even if ants in reality tended the eggs 

 of aphides only on account of a combination of their 

 sensitive experiences, this would be as yet no proof 

 of their intelligence, but merely of their memory. 

 In reality, however, the case is different. Take a few 

 newly developed workers of a Lasius nest and unite 

 them to form an autodidactic colony, restricted to its 

 innate instincts without a shadow of experimental 



