154 BIOLOGICAL LECTURES. 



of the parent, and impressed in greater or less part on the germ 

 plasma, in the order in which it was stored. The basis of memory 

 is reasonably supposed to be a molecular (or atomic) arrangement 

 from which can issue only a definite corresponding mode of action. 

 That such an arrangement exists in the central nervous organism is 

 demonstrated by automatic and reflex movements. 1 



Any naturalist who has studied the sudden recurrence of 

 habits in animals, usually accounted for by the use of the mean- 

 ingless term "instinct," will find that this is no figment of the 

 imagination, but a working hypothesis that may be used and 

 tested. 



Although Ribot's work on " Heredity " has not been widely 

 read or accepted by scientists, perhaps because he admits many 

 facts as substantial evidence which have not been verified, it is 

 nevertheless the most profound work on this subject that has 

 been published. This learned authority, after careful investi- 

 gation, came to the same startling conclusion that memory was 

 the only function of organisms which could be closely compared 

 with heredity, and he brings forward a large number of facts, 

 to which many others can be easily added. He says " heredity, 

 indeed, is a specific memory; it is to the species what memory 

 is to the individual. Facts will hereafter show that this is no 

 metaphor." 



The authors quoted above have not discussed memory, as 

 has been commonly supposed by naturalists, in a metaphysical 

 sense, but as an organic function arising from voluntary or 

 involuntary repetitions of conscious or unconscious actions. 

 Ribot indulged in general speculations and was hampered by 

 them to a notable extent, but he struck the keynote of the 

 dynamical theory of evolution. Thus he say^ : " Every act 

 leaves in our physical and mental constitution a tendency to 

 reproduce itself, and whenever this reproduction occurs the 

 tendency is strengthened ; and thus a tendency, often repeated, 

 becomes automatic. This automatism is the link between 

 memory and habit, and gave rise to the saying that memory is 



1 American Naturalist, vol. xvi, 1882, pp. 454-469; reprinted in The Origin of 

 the Fittest, pp. 405-421, and " On Inheritance in Evolution," American Naturalist, 

 vol. xxiii, 1889, pp. 1058-1071. 



