nerve junctions with the motor nerve cells; and so nervous disturbances coming from the cerebellum can arouse the muscles to activity. We all know that walking or any other locomotor act, after it has once been learned, is carried on successfully without our performing any intellectual work in connection with it. What we do have to do is to start the act, and this is done through a discharge from the cerebrum; either some sense organ is aroused and sends a disturbance into the cerebrum, which arouses in us an association which indicates the necessity for going somewhere, or else a pure memory not stimulated from outside has the same effect. In either case the nervous disturbance passes over from the cell where the association resides to the motor area, and from there down to start the act of walking; but as soon as it is started, the reflex takes hold and carries it on without any further thought on our part except as some additional associations enter to cause us to change or perhaps to stop the action. It is possible that the complex muscular acts which we group under the head of grasping are operated in similar fashion. For example, the act of writing is essentially a modified grasping movement. When we are writing we think not about the muscular movements but about the sense of what is being written, and it may be that the actual control of the muscles in this case is something like that which we know exists in locomotion, although this is by no means certain. It is of course a very great advantage to us to have these complicated activities, which we are performing so constantly, carried on as reflexes without conscious effort on our part. If we had to think about the movement of every muscle, whenever we started to walk, our minds would be so taken up with the act itself that there would be no freedom for anything else; but since the reflex machinery takes care of these muscular movements for us, our minds are left free to deal with other matters at the same time as the muscular actions are going on.