974 The American Ni aturalist. | [December, 
investigate alone the wind and temperature apparatus on the 
roof in order to discover why we hear the bell ring instead 
of see the index move. But, rather he would extend his in- 
vestigations to discovering how the “ nerve ” connections origi- 
nated that now exist, and how the internal apparatus, to which 
they run, came to be so different that in one case we “ see ” and 
in the other “ hear” from the same sort of incoming current. 
Enabled by this illustration to look with greater clearness 
into Prof. James’ hypothesis, and into some of its implications, 
we may now go back to the assertions that vastly different 
spheres of evolutionary influence would be involved as between 
this theory that these currents are alike and the rival theory 
that they are different, and to the assertion that certain conse- 
quences are logically demanded by the “alike” theory which 
are so contrary to existing facts that it must be discarded. 
What has been neglected by Prof. James is, as I have said, 
the evolutionary or selective value of the sensory currents. If 
these currents were all alike, then, manifestly the molecular 
differences which we are obliged to assume in the cortex as 
underlying our different sensations would be cut off from all 
diversity of influence either from the end-organ processes or 
from the environmental forces. And this is the same as saying 
that they would be cut off from all selective relationship with these 
great spheres of influence, and that our end-organs and environment 
had nothing whatever to do with the origin of our different senses. 
Now, it must not be too quickly inferred from these words 
in italics, that it would be impossible to account for the 
evolutionary selection of our several senses within the nar- 
rowed sphere of influences remaining after cutting off the 
peripheral and outer forces. Such an inference would not only 
be wrong but also would confuse and obscure certain considera- 
tions that we are to come to further on, and in view of which 
it is imperative for me to stop long enough here to point out 
that the sphere of Spontaneous Variation alone might be suffi- 
cient to account for the variety of our senses and their present 
external connections, if only their origin and not their preservation 
needed to be accounted for. And this is done in pointing out 
that these connections might be originally due wholly to the _ 
