Hyatt.] 
[April s, 
Although Ribot's work on "Heredity"^ has not been widely read 
or accepted by scientists, perhaps because he admits as substantial 
evidence many facts which have not been verified, it is neverthe- 
less by far the most profound work on this subject that lias been 
))ublished. This learned authority after careful investigation came 
to the same startling conclusion that memory was the only func- 
tion of organisms w^iich could be closely compared with heredity, 
and he brings forward a large number of facts to which many others 
can easily be added. He says ' 'heredity, indeed, is a specific mem- 
ory ; it is to the species what memory is to the individual. Facts 
will hei-eafter show that this is no metaphor, bnt a positive truth.'' 
Any naturalist who has studied the sudden recurrence of habits 
in animals, usually accounted for by the use of the meaningless terra 
instinct, will find that this is no figment of the imagination but a 
working hypothesis that may be used and tested. 
The authors quoted above have not discussed memory, as has been 
commonly sujjposed by naturalists, in a metaphysical sense, but as 
an organic function arising from voluntary or involuntary repeti- 
tions of conscious or unconscious actions. Ribot indulged in gen- 
eral speculations and was hampered by them to a notable extent, 
but he struck the keynote of the dynamical theory of evolution. 
Thus he says : "Every act leaves in our physical and mental consti- 
tution a tendency to reproduce itself, and whenever this reproduc- 
tion 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 mem- 
ory is oidy a form of habit — a proposition which, with some 
restrictions, is true." 
Repetition or the reproduction of parallelisms is equally charac- 
teristic of memory and of heredity, nor can either be conceived of 
as having a tendency to produce variations. It is entirely reason- 
able that any newly acquired habit, due to conscious effort or to 
the involuntary reactions of organisms in tlie presence of external 
stimuli, may be regarded as one of the products of memory. It 
follows from this, that any structural modifications which may 
result from the repetition of the same acts or habits, can with 
ecpial reason 1)0 attributed to memory. The tendency of descen- 
dants to |)(>rf<)nii the same action, i. e., to manifest the same habit 
' IK'iuditv, Translation, New York, 1876. 
