16, last chord; No.

38, last chord; No.

6, last three measures (the 5th of the tonic chord as uppermost tone).

At any other point in the piece this default of the keynote would, as we shall presently see, almost certainly reduce the weight of the cadence from "perfect" to "semicadence"; at the very end, however, it cannot mislead, because it does not affect the condition of actual finality.
SEMICADENCE .-- Any deviation from the formula of the perfect cadence--either in the choice of some other than the tonic chord, or in the omission of the keynote in either (or both) of the outer parts--weakens the force of the interruption, and transforms the cadence into a lighter, more transient, point of repose, for which the term semicadence (or half-stop) is used.

The semicadence indicates plainly enough the end of its phrase, but does not completely sever it from that which follows.
It is these lighter, transient forms of cadence to which a number of different names are given; for the student of analysis (and the composer, also, for that matter) the one general term "semicadence," or half-cadence, is sufficient, and we shall use no other.
If, then, a cadence is final in its effect, it is a perfect one; if not, it is a semicadence.