ANTS — GENEKAL INTELLIGENCE. 123 



seem to admit of being reasonably comprised under the 

 category of instinctive action, if by the latter we mean 

 action pursued without knowledge of the relation between 

 the means adopted and the ends attained. 



It will be remembered that our test of instinctive as 

 distinguished from truly intelligent action is simply 

 whether all individuals of a species perform similar adap- 

 tive movements under the stimulus supplied by similar 

 and habitual circumstances, or whether they manifest in- 

 dividual and peculiar adaptive movements to meet the 

 exigencies of novel and peculiar circumstances. The im- 

 portance of this distinction may be rendered manifest by 

 the following illustrations. 



We have already seen that the ants which Sir John 

 Lubbock observed display many and complex instincts, 

 which together might seem to justify us in anticipating 

 that animals which present such wonderful instincts must 

 also present sufficient general intelligence to meet simple 

 though novel exigencies by such simple adaptations as the 

 unfamiliar circumstances require. Yet experiments which 



Fig. 8. 



he made in this connection seem to show that such is not 

 the case, but that these ants, with all their wealth of 

 instinctive endowments, are utterly destitute of intelli- 

 gent resources; they have abundance of common and 

 detailed knowledge (supposing the adaptations to be made 

 consciously) how to act under certain complex though 

 familiar circumstances, but appear quite unable to origi- 

 nate any adaptive action to obviate even the simplest 

 conceivable difficulty, if this is of a kind which they have 

 not been previously accustomed to meet. Thus, on a 

 horizontal rod B supported in a saucer of water s, and 

 therefore inaccessible to the ants from beneath, he placed 

 some larvae a. On the nest N he then placed a block of 

 wood c D, constructed so that the portion D should touch 



