212 
general habits and reactions of the animals 
used as possible. The labyrinth method, in 
various forms, has been used for all the 
work. Observations have thus far been 
made on the crayfish, green crab, fiddler 
crab, newt, frog and turtle. Crayfish in a 
simple labyrinth, involving choice of direc- 
tion only once, improve rapidly from fifty 
per cent. correct in the first ten trials to 
ninety per cent. correct in the sixth ten. 
There is evidence of the habit (7. e., mem- 
ory) after two weeks’ rest. Newts, judging 
from these studies, learn very slowly and 
there is successive variability among in- 
dividuals. Frogs alone, of the animals 
named, have shown the formation of a 
habit as the result of a single experience. 
Turtles are very apt in the formation of 
labyrinth habits, and retain them for weeks. 
They give a curve of learning very similar 
to those of the cat and dog. In all the ex- 
periments record is kept of the time taken 
to escape from the labyrinth and of the 
course followed. 
This paper was succeeded by one by Dr. 
Shepherd Ivory Franz, of the Harvard 
Medical School on ‘ Frontal Lobes and As- 
sociation.’ The experiments were under- 
taken to determine whether or not the 
frontal lobes in animals are concerned in 
the production of certain sensory-motor 
associations. Cats were given the oppor- 
tunity of learning simple habits, after the 
learning of which the frontal area anterior 
to the crucial sulcus was excised. After 
the operation the habits previously learned 
were lost. A series of control experiments 
shows that this result cannot be accounted 
for on the supposition of surgical shock. 
The conclusion was drawn that the frontal 
lobes are normally concerned in the forma- 
tion of these habits. The animals that had 
thus acquired and lost certain associations 
were found to have the ability for re-learn- 
ing these habits and for acquiring new ones. 
This ability (e-learning) may be due to the 
SCIENCE. 
[N. S. Vou. XIII. No. 319. 
use Of other association areas (either the 
parietal or the occipito-temporal lobes), but 
the evidence is not yet complete. 
Dr. R. S. Woodworth and Dr. E. L. 
Thorndike reported the results of the con- 
tinuation of their experiments on ‘ The In- 
fluence of Special Training on General 
Ability.’ The following conclusions seem 
to them justifiable : 
The mind is, on its dynamic side a ma- 
chine for making particular reactions to par- 
ticular situations. It works in great detail, 
adapting itself to the special data of which 
it has had experience. Change in the time 
or precision or quality of any one of these 
particular reactions need not and often 
does not influence appreciably other reac- 
tions, similar enough to be called by the 
same name. Change in any one almost 
never brings about an equal change in any 
other reaction, no matter how similar, for 
the working of every mental function is 
conditioned by the nature of the data on 
which the function is employed. The 
amount of influence of changes in any one 
mental function upon others is much less 
than has been supposed. ‘The cases of 
such influence and of its absence make it 
seem probable that change in one function 
affects others only where and in so far as 
identical elements are present in both. By 
identical elements are meant concrete ele- 
ments, such as sensations, images, move- 
ments, etc., the actual content of which is 
identical. : 
Professor J. McK. Cattell reported on 
“Psychological Tests of Abnormal and Ex- 
ceptional Individuals.’ Attention was called 
to the desirability of extending physical and 
mental tests to those suffering from disabil- 
ities and disease on the one hand, and to 
those showing exceptional aptitudes on the 
other. A description was given of cases of 
nervous disease tested by the speaker, and 
it was shown how these differed from nor- 
mal individuals and how far the nature and 
