The Mysterious Cage

There is this mysterious cage surrounding the head and upper body that I accidentally added by means unknown to me. I need to remove it and have been unable to figure out how. It is not due to a modifier. The scalp object that is selected whenever this cage becomes a yellow color does not have such a modifier. The file can be downloaded at:

When I first saw this, I thought that it might be a lattice modifier. Turns out, it’s connected to the hair particle system. On the particles properties tab, look under Hair Dynamics. You have the Hair Grid box checked.