26 Instinct and Intelligence 



From the above evidence, which we can con- 

 firm by our own experience, we hold that the 

 behaviour displayed in response to appropriate 

 stimuli by the simplest forms of animals is 

 instinctive, employing that term as defined by 

 Professor Lloyd Morgan (p. 19). The behaviour, 

 however, of the Amoeba above referred to was 

 to some extent the result of memory. Huxley, 

 in his well-known address to the British Asso- 

 ciation in the year 1874, referring to this sub- 

 ject, remarks that impressions made on certain 

 kinds of living matter leave behind molecules 

 competent on being stimulated to their repro- 

 duction " sensigenous molecules," so to speak, 

 which, he adds, " constitute the physical 

 foundation of memory." We thus arrive at the 

 conclusion that not only instinctive behaviour, 

 but also memory, is a fundamental property of 

 living animal protoplasm. This idea is sub- 

 stantiated by the following evidence : 



Sir Francis Darwin, in his address as Presi- 

 dent of the British Association in the year 1908, 

 not only concurs in Huxley's views on this sub- 

 ject, but quotes Regnano, Hering, and Semon 

 as postulating the existence in living proto- 



