। ॥ ४०० ॥
In plain words
So each of the elements, space and the rest, ends up with five portions in it: each gives away its own half, and from the other four a set of four portions comes back to it.
Close to the Sanskrit
Then, of the elements beginning with ether, those portions become five; by each one's own half-portion, a set of four portions is obtained from the others.